Dissertations / Theses: 'Biological treatment systems'

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Tjernström, Linnéa. "Function of soil-based on-site wastewater treatment systems - Biological and chemical treatment capacity." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210716.

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On-site wastewater treatment systems are among the main Swedish anthropogenic sources of nutrients causing euthropication of the Baltic Sea. Among on-site systems in Sweden almost half have septic tank treatment followed by a soil-based system, in which the wastewater is treated through soil filtration. In this study a soil based technique for on-site wastewater treatment is studied where wastewater is filtered through a sand filter. Composite samples of influent and effluent at two sand filters in the area of Stockholm are sampled to determine their chemical and biological function and to compare their treatment capacity to requirements. Parameters within the scope of the study are tot-P, NH4-N, DOC, pH, turbidity and dissolved oxygen. Biological function was considered to be good in both systems as nitrification was high and the effluent had sufficient levels of dissolved oxygen suggesting aerobic conditions. Prevailing aerobic conditions in the sand filters would also indicate good reduction of organic substances which is the case for DOC as it was reduced by above 85 % for one site and almost 70 % for the other site. The overall high reduction of organic micropollutants in the systems, reported in another study, also suggests that biological function when it comes to reduction of organic substances is good. On the other hand, chemical function, with respect to reduction of phosphorus, was not sufficient as none of the systems fulfilled the requirements from HaV for normal or high protection level. In the systems tot-P was reduced by 42 and 54 % respectively. A drawback with the method approach used in the study is that the obtained reduction results only can represent the actual situation if variations in incoming and outgoing flow, variations in influent concentrations and magnitude of dilution of effluent compared to daily wastewater load are small. As these are unknown in this case it adds uncertainty to the results.
Decentraliserade system för rening av avloppsvatten är bland de huvudsakliga svenska antropogena källorna till näringsämnen som bidrar till övergödning av Östersjön. Bland decentraliserade system i Sverige är nästan hälften system med slamavskiljare följt av ett markbaserat system i vilket avloppsvattnet renas genom infiltration i jord. I denna studie studeras en markbaserad teknik i vilken avloppsvattnet filtreras genom sand, en så kallad markbädd. En fältundersökning gjordes där samlingsprov av ingående och utgående avloppsvatten togs på två markbäddar i Stockholmsområdet för att bestämma deras biologiska och kemiska reningsfunktion samt att jämföra avskiljningen av fosfor i systemen med rekommendationer från HaV. Parametrar som inkluderats i studien är totalfosfor, ammonium-kväve, löst organiskt kol, pH, turbiditet och löst syre. Biologisk funktion ansågs bra i båda markbäddarna eftersom nitrifikationen var hög och utgående vatten hade tillräckliga halter av löst syre vilket implicerar att markbäddarna var väl syresatta. Rådande syrerika förhållanden i markbäddarna antyder också att organiskt material bryts ned avsevärt, vilket är fallet för löst kol som reducerades med mer än 85 % i en av markbäddarna och med nästan 70 % i den andra. Den höga reduktionen av organiska mikroföroreningar som påvisats i markbäddarna i en annan studie tyder också på att biologisk funktion med avseende på avsklijning av organiska substanser är bra. Kemisk funktion, med avseende på avskiljning av totalfosfor, var inte tillräcklig då ingen av markbäddarna levde upp till reduktionskraven från HaV för normal eller hög skyddsnivå. Totalfosfor avskiljdes med 42 respektive 54 % i markbäddarna. En nackdel med metoden som användes i studien är att de resultat som fåtts för avkiljning av de olika parametrarna endast kan representera den verkliga situationen om variationer i in- och utgående flöde samt variationer i ingående vattenkoncentrationer är små och om utspädningseffekten av utgående vatten är försumbar.

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Wells, Charles Digby. "Tertiary treatment in integrated algal ponding systems." Thesis, Rhodes University, 2005. http://hdl.handle.net/10962/d1006162.

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Inadequate sanitation is one of the leading causes of water pollution and consequently illness in many underdeveloped countries, including South Africa and, specifically, the Eastern Cape Province, where cholera has become endemic. As modern wastewater treatment processes are often energy intensive and expensive, they are not suitable for use in these areas. There is thus a need to develop more sustainable wastewater treatment technologies for application in smaller communities. The integrated algal ponding system (IAPS) was identified as a possible solution to this wastewater management problem and was investigated for adaptation to local conditions, at the Rhodes University Environmental Experimental Field Station in Grahamstown, South Africa. The system was monitored over a period of nine years, with various configuration adjustments of the high rate algal pond (HRAP) unit operation investigated. Under standard operating conditions, the system was able to achieve levels of nutrient and organic removal comparable with conventional wastewater treatment works. The mean nitrate level achieved in the effluent was below the 15mg.l-1 South African discharge standard, however, nitrate removal in the IAPS was found to be inconsistent. Although the system was unable to sustain chemical oxygen demand (COD) removal to below the 75mg.l-1 South African discharge standard, a removal rate of 87% was recorded, with the residual COD remaining in the form of algal biomass. Previous studies in the Eastern Cape Province have shown that few small wastewater treatment works produce effluent that meets the microbial count specification. Therefore, in addition to the collation of IAPS data from the entire nine year monitoring period, this study also investigated the use of the HRAP as an independent unit operation for disinfection of effluent from small sewage plants. It was demonstrated that the independent high rate algal pond (IHRAP) as a free standing unit operation could consistently produce water with Escherichia coli counts of 0cfu.100ml-1. The observed effect was related to a number of possible conditions prevailing in the system, including elevated pH, sunlight and dissolved oxygen. It was also found that the IHRAP greatly enhanced the nutrient removal capabilities of the conventional IAPS, making it possible to reliably and consistently maintain phosphate and ammonium levels in the final effluent to below 5mg.l-1 and 2mg.l-1 respectively (South African discharge standards are 10mg.l-1 and 3mg.l-1 in each case). The quality of the final effluent produced by the optimisation of the IAPS would allow it to be used for irrigation, thereby providing an alternative water source in water stressed areas. The system also proved to be exceptionally robust and data collected during periods of intensive and low management regimes were broadly comparable. Results of the 9 year study have demonstrated reliable performance of the IAPS and its use an appropriate, sustainable wastewater treatment option for small communities.

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Macpherson, Alisdair N. "New sensitisers for photodynamic therapy : a photophysical study in model and biological systems." Thesis, Keele University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305882.

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Woudneh, Million Bekele. "Mechanisms and factors affecting removal of herbicides by biological filters." Thesis, University of Surrey, 1996. http://epubs.surrey.ac.uk/843258/.

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A critical review of the mechanisms of present water treatment systems including, chlorination, coagulation, filtration, granular and powdered activated carbon adsorption, ozonation and ultraviolet radiation for the removal of herbicides is presented. Rapid selective and sensitive HPLC methods were developed and rigorously validated for the analysis of the selected herbicides. Analysis of atrazine was made using Cl8 cartridges. For raw water containing interferences, extraction of the compound was made on SCX cartridges, followed by solvent exchange on C18 cartridges. A quantitative recovery of virtually 100% of the compound was achieved using C18. While the double cartridge extraction of the compound gave a recovery of about 89%. Previously developed methods for 2,4-D and MCPA were rigorously validated for the extraction and analysis of 2,4-D and MCPA. A quantitative recovery of usually greater than 90% was achieved for both compounds using Cl8 cartridges. For the extraction of paraquat different extraction systems including, reversed phase on C8 and C18, ion-paired reversed phase on C18, and cation exchange on SCX, CBA, and CN were investigated. A quantitative recovery, usually greater than 90%, of the compound was obtained using CN and CBA cartridges. The methods were then successfully used for the evaluation of the removal efficiency and establishment of mechanisms of removal of herbicides by biological filters at bench and pilot scale. Four herbicides belonging to three broad chemical categories were studied. The data presented in this study demonstrated that biological filters are very efficient in removing certain classes of herbicides. 2,4-D and MCPA were consistently removed to below a detection limit of 0.1 mug/1 for an influent concentration of 3-11 mug/1. Process variables such as flow rate, bed depth and contact time were investigated for the efficient removal of these herbicides. Seasonal variations in performance were observed and possible explanations proposed. A series of experiments was undertaken to establish .mechanisms of removal. Quantitative recovery of the herbicides from the river water proved that the processes in the filter bed as opposed to the processes in the water were responsible for removal of the herbicides. It was clear from the investigation of the adsorption of the herbicides both on the sand and organic and inorganic dirt that adsorption on these surfaces was not the main reason for removal. Filter maturation experiment showed that the presence of microorganisms in the bed is a precondition for the removal of herbicides. A depth experiment for the removal of 2,4-D showed that superficial efficient zone of removal imitates the distribution of microbial density. This evidence confirms the significance of microorganisms for the removal of herbicides by the filter bed. The ultimate proof of the biodegradation of 2,4-D by microorganisms in the filter bed was the identification of the biodegradation product 2-chlorophenol as predicted by the metabolic pathways of the compound. Filter design modifications using activated carbon were made to accommodate the removal of 'non-biodegradable' herbicides. A sandwich sand / GAC / sand filter was investigated. Filter efficiency for this arrangement was determined and short-comings were identified and a possible solution in the form of a double GAC sandwich is suggested.

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Giles, Hamilton. "Biotransformation potential of phytosterols in biological treatment systems under various redox conditions." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48993.

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Phytosterols are naturally occurring compounds which regulate membrane fluidity and serve as hormone precursors in plants. They also have the potential to cause endocrine disturbances in aquatic animals at concentrations as low as 10 µg/L. Wastewaters from several industries which process plant matter can contain phytosterols at concentrations in excess of the above-stated level. Despite their endocrine disruption potential, very little is known about phytosterol physical properties and their biotransformation potential in biological treatment systems. Aerated stabilization basins (ASBs) are common biological treatment systems in North American pulp and paper mills. ASBs are large open lagoons which use tapered surface aeration to remove COD and prevent sulfate reduction in the water column. Phytosterols are released from wood during the pulping process and a small fraction enters the wastewater stream during washing of the pulp. Therefore, phytosterols may be exposed to aerobic or anaerobic environments depending on their solubility and solid-liquid partitioning behavior. The overall objective of this research was to systematically and quantitatively assess the biotransformation potential of phytosterols in biological treatment systems and to examine conditions leading to reduction of these compounds in wastewater effluent streams. The results of this research showed that phytosterols are sparingly soluble with aqueous solubility below 1 µg/L when present as a mixture. Phytosterols have a strong affinity to adsorb to solids and dissolved organic matter. The affinity for aerobic biomass was greater than for wastewater solids. The stigmasterol desorption rate and extent from wastewater solids increased with an increase in pH from 5 or 7 to 9. Phytosterols were biotransformed under aerobic conditions but not under sulfate-reducing or methanogenic conditions by stock cultures developed in this study. Biotransformation under nitrate-reducing conditions could not be confirmed conclusively. The continuous-flow system was successful in removing 72 to 96% of phytosterols. Biotransformation accounted for 23, 14 and 41 % of campesterol, stigmasterol and β-sitosterol removal, respectively. Phytosterols accumulated in the reactor sediment and accounted for 97 % of the total phytosterols remaining in the system. Phytosterols can be removed from wastewater streams during biological treatment by a combination of biotransformation and solids partitioning and control of system pH, DO and available carbon and energy sources can increase the degree of phytosterols removal. The results of this research can be used to engineer effective biological treatment systems for the removal of phytosterols from pulp mill wastewaters and other phytosterol-bearing wastewater streams.

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Cameron, Kimberley A. "The efficiency and mechanisms for pollutant removal in biological wastewater treatment systems /." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33724.

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The research project was initiated to refine the knowledge available on the treatment of rural municipal wastewater by constructed wetlands. Field and laboratory studies were conducted to determine the treatment capacity of a constructed wetland system and to determine a substrate that would be most efficient as a phosphorus adsorption filter. The wetland system consisted of three free-water surface cells, three blast furnace slag filters and a vegetated filter strip, treating municipal wastewater. Bimonthly water samples at the inlet and outlet of each component of the wetland system were analysed for biochemical oxygen demand, nitrate and nitrite, ammonia and ammonium, total Kjeldahl nitrogen, total suspended solids, total phosphorus, ortho-phosphate, fecal coliforms and E. coli. Phosphorus and nitrogen concentrations were determined in the sediment, plant tissue and water column of the free-surface wetland cells. The free-surface wetland cells achieved removals as follows: ammonia and ammonium (52%), total Kjeldahl nitrogen (37%), total suspended solids (93%), total phosphorus (90%) and ortho-phosphate (82%). The vegetated filter strip achieved removals as follows: ammonia and ammonium (28%), total Kjeldahl nitrogen (11%), total suspended solids (22%), total phosphorus (5%) and ortho-phosphate (0%). The slag filters reduced total phosphorus by more than 99%. Phosphorus adsorption measurements were conducted on slag, calcite and shale. Slag was found to be the most effective at removing phosphate.

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Edwards, Justin Kenneth. "Reed bed systems for the treatment of wastewaters and for sludge dewatering." Thesis, University of Birmingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343453.

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Rodriguez-Gonzalez, Laura C. "Advanced Treatment Technologies for Mitigation of Nitrogen and Off-flavor Compounds in Onsite Wastewater Treatment and Recirculating Aquaculture Systems." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6941.

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Non-point sources (NPS) of pollution are non-discernable, diffuse sources of pollution that are often difficult to localize and in turn mitigate. NPS can include stormwater runoff, agricultural/aquaculture wastes and wastes from small decentralized wastewater treatment systems, such as conventional septic systems. The mitigation of these NPS is imperative to reduce their potential detrimental effects on the water environment. This dissertation addresses novel treatment technologies for the mitigation of nutrients, particularly nitrogen, in Recirculating Aquaculture Systems (RAS) and onsite wastewater treatment systems (OWTS). The removal of trace organics limiting RAS production and water reuse were also investigated. The first question this dissertation addressed is: Can the application of a UV-TiO2 reactor reduce the concentration of off-flavor compounds in RAS? In the UV-TiO2 reactor, spray-coated TiO2 plates were placed in an aluminum reactor and exposed to UV light. The process was applied in both a full-scale sturgeon RAS and a bench-scale RAS for the degradation of Geosmin (GSM) and 2-methylisoborneol (MIB). Improved performance on the removal of GSM and MIB was observed when the UV-TiO2 was applied as a batch reactor since it allowed for a longer treatment time without the effect of constant production of the compounds in the biological treatment processes. Treatment performance of UV-TiO2 was affected by GSM and MIB concentrations and dissolved oxygen. No harmful effects were observed on other water quality parameters when the UV-TiO2 reactor was operated as a batch or side stream process. The second question this dissertation addressed is: Does the application of Tire-Sulfur Hybrid Adsorption Denitrification (T-SHAD) in RAS improve nutrient and off-flavor compound removal when compared to conventional heterotrophic denitrification? T-SHAD combines tire mulch as an adsorbent and sulfur oxidizing denitrification for the removal of NO3--N from the aquaculture waters. Adsorption studies showed the tire has significant adsorption capacity for the off-flavor compounds GSM and MIB but can be limited by contact time and, possibly, the presence of competing organic matter in RAS. The application of T-SHAD as an effluent polishing step in RAS with a high empty bed contact time (EBCT) of 720 min removed 96.6% of NO3--N and 69.6% of GSM. The application of T-SHAD within RAS as denitrification side treatment for NO3--N removal resulted in lower EBCT (185 min) that limited NO3--N removal to 21% and showed no significant removal of off-flavor compounds. The comparison between T-SHAD and a molasses fed heterotrophic upflow packed bed reactor (UPBR), showed no significant differences in N species concentrations as well as off-flavor compound removal. However, high production of SO42- resulted from sulfur oxidizing denitrification (SOD) processes was noted. Hybrid Adsorption and Biological Treatment Systems (HABiTS), is composed of two biofilters in series employing ion exchange (IX) and nitrification for removal of NH4+ and tire scrap coupled with sulfur chips and oyster shells for both adsorption and SOD of NO3-. The third question addressed in this dissertation is: What IX/adsorption media best balances both ammonium removal and cost effectiveness for application in OWTS? Adsorption isotherms performed with different media materials showed that the zeolite material, clinoptilolite, was the best medium for the nitrification stage of HABiTS due to its high IX capacity for NH4+and cost. An adsorption capacity of 11.69 mg g-1 NH4+-N when in competition with other cations present in septic tank effluents was determined by the IX model fit to the data. The cost of clinoptilolite is significantly higher than the other media materials tested. However, the high adsorption capacity would allow for low dosages that can be combined with non-adsorptive material reducing overall costs. The fourth question this dissertation addressed is: How is the BNR process within HABiTS affected by IX? Results from side-by-side biofilter studies with HABiTS and a conventional nitrification/denitrification biofilter showed that the combined IX and nitrification in HABiTS can allow for faster startup, sustain variable loading, and achieve over 80% removal of NH4+ at a hydraulic loading rate of 0.34 m3 m-2-d-1 when compared to the conventional biofilter with 73% removal. Under lower loading rates the biological treatment was enhanced and dominated the NH4+ removal processes in both columns. The addition of a denitrification stage decreased Total Inorganic Nitrogen (TIN) by 53.54% and 40.97%, for the HABiTS treatment and the control treatment, respectively, under loading rates of 0.21 m3 m-2-d-1. Further decrease of NH4+-N loading rates results in high desorption of exchanged NH4+ in the clinoptilolite, resulting in lower TIN removal efficiencies (28.7%) when compared to the conventional control treatment (62%). The final question addressed in this dissertation is: Does the proposed hybrid system enhance the removal of TIN in OWTS under transient loading conditions? Further studies with HABiTS and the conventional biofilter were performed to determine N removal performance on an hourly basis. It was found that the performance of HABiTS varies with daily and hourly loads, particularly when recovering from periods of very low loading to high loadings and vice versa. If recovering from low loading periods, IX is observed for HABiTS and the biofilter outperforms the conventional treatment in overall TIN removal. However, recovery from a high loading period results in release of NH4+-N stored in the clinoptilolite and increased production of NO3--N that could affect the performance of the denitrification stage.

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Ramjohn, Jamal Stephen. "The use of solar aquatic biological wastewater treatment systems in sustainable community design." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0018/MQ47650.pdf.

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Sanyahumbi, Douglas. "Capsule immobilisation of sulphate-reducing bacteria and application in disarticulated systems." Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1003994.

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Biotechnology of sulphate reducing bacteria has developed rapidly in recent years with the recognition of their extensive and diverse biocatalytic potential. However, their application in a number of areas has been constrained due to problems including poor cell retention within the continuous bioprocess reactor environment, and contamination of the treated stream with residual organic feed components and cell biomass. These problems have so far excluded the application of biological sulphate reduction in the treatment of ‘clean’ inorganic waste streams where components such as sulphate, acidity and heavy metal contamination require treatment. This study investigated the effective immobilisation of sulphate reducing bacterial cultures and proposed that the disarticulation of the electron donor and carbon source supply using such systems would create the basis for their application in the treatment of ‘clean’ inorganic waste streams. A functional and stable sulphate reducing culture was selected and following evaluation using a number of techniques, was immobilised by encapsulation within a calcium-alginate-xanthum gum membrane to give robust capsules with good sulphate reduction activity. The concept of disarticulation was investigated in a swing-back cycle where the carbon source was excluded and the electron donor supplied in the form of hydrogen gas in a continuous up-flow capsule-packed column reactor. Following a period of operation in this mode (4-12 days), the system was swung back to a carbon feed to supply requirements of cell maintenance (2-3 days). Three types of synthetic ‘clean’ inorganic waste stream treatments were investigated, including sulphate removal, neutralisation of acidity and heavy metal (copper and lead) removal. The results showed: • Sulphate removal at a rate of 50 mg SO₄²⁻L/day/g initial wet mass of capsules during three 4-day cycles of electron donor phase. This was comparable to the performance of free cell systems; • Neutralisation of acidity where influent pH values of 2.4 and 4.0 were elevated to above pH 7.5; • Copper removal of 99 and 85 % was achieved with initial copper concentrations of 2 and 60 mg/L respectively; • Percentage lead removal values of 49 and 78 % were achieved; This first report on the application of the concept of capsular immobilisation and disarticulation in the treatment of ‘clean’ inorganic waste streams will require future studies in order to extend the development of the full potential of the concept.

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Smith, Jennifer Mary. "Detection of Ammonia-Oxidizing Beta-Proteobacteria in Swine Waste Treatment Systems." NCSU, 2004. http://www.lib.ncsu.edu/theses/available/etd-09162004-173714/.

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In order to obtain supporting evidence for biological denitrification in anaerobic lagoons degenerate ?Ò-Proteobacterial AOB primers were used to create and sequence clone libraries to detect the presence of ammonia-oxidizing bacteria at three field sites. Although there were PCR products from almost all samples, the clone libraries that were created show that not all PCR reactions produce only PCR products from ammonia-oxidizing bacteria. However, these primers did verify the presence of ammonia-oxidizers at one site, although their presence was not verified at the other sites. The presence of ammonia-oxidizers at the Battelle site implies that aerobic ammonia-oxidation is occurring. Clones were created and sequenced that were significantly different from other known sequences and tended to form very closely related phylogenetic groups. These phylogenetic groups were not isolated to one field site, and often more than one site had representatives in a closely related group. Future research in this field includes the design of new primer sets based on the sequences of the nitrifying bacteria clones reported in this research, creation of enrichment cultures, and use of new primers for fluorescent in situ hybridization.

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Stocks, Justine L. "Enhancement of Two Passive Decentralized Biological Nitrogen Removal Systems." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/7093.

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This research evaluates two different Biological Nitrogen Removal (BNR) systems for enhanced nitrogen removal in decentralized wastewater treatment. The first study evaluated the performance of Hybrid Adsorption and Biological Treatment Systems (HABiTS) at the pilot scale with and without stage 1 effluent recirculation. HABiTS is a system developed at the bench scale in our laboratory and was designed for enhanced BNR under transient loading conditions. It consists of two stages; an ion exchange (IX) onto clinoptilolite media coupled with biological nitrification in the aerobic nitrification stage 1 and a Tire-Sulfur Adsorption Denitrification (T-SHAD) system in the anoxic denitrification stage 2. The T-SHAD process incorporates NO3- adsorption onto tire chips and Sulfur Oxidizing Denitrification (SOD) using elemental sulfur as the electron donor for NO3- reduction. Previous bench scale studies evaluated HABiTS performance under transient loadings and found significantly higher removal of nitrogen with the incorporation of adsorptive media in stage 1 and 2 compared with controls (80% compared to 73%) under transient loading conditions. In this study, we hypothesize that a HABiTS system with effluent recirculation in nitrification stage 1 may enhance nitrogen removal performance compared to that without recirculation. The following were the expected advantages of Stage 1 effluent recirculation for enhanced nitrogen removal: 1) Pre-denitrification driven by the mixture of nitrified effluent from stage 1 with high concentrations of biochemical oxygen demand (BOD) septic tank effluent. 2) Moisture maintenance in stage 1 for enhanced biofilm growth. 3) Increased mass transfer of substrates to the biofilm in stage 1. 4) Decreased ratio of BOD to Total Kjeldahl Nitrogen (TKN) in the influent of stage 1. Two side-by-side systems were run with the same media composition and fed by the same septic tank. One had a nitrification stage 1 effluent recirculation component (R-system), which operated at a 7:1 stage 1 effluent recirculation ratio for the first 49 days of the study and at 3:1 beginning on day 50 and one was operated under forward flow only conditions (FF-system). The R system removed a higher percentage of TIN (35.4%) in nitrification stage 1 compared to FF (28.8%) and had an overall TIN removal efficiency of 88.8% compared to 54.6% in FF system. As complete denitrification was observed in stage 2 throughout the study, overall removal was dependent on nitrification efficiency, and R-1 had a significantly higher NH4+ removal (87%) compared to FF-1 (70%). Alkalinity concentrations remained constant from stage 1 to stage 2, indicating that some heterotrophic denitrification was occurring along with SOD, as high amounts of sCOD leached from the tire chips in the beginning of the study, reaching sCOD concentrations of 120-160 mg L-1 then decreasing after day 10 of operation of stage 2. Sulfate concentrations from stage 2 for each side were low until the last 10 days of the study, with an average of 16.43 ± 11.36 mg L-1 SO42--S from R-2 and an average of 16.80 ± 7.98 SO42--S for FF-2 for the duration of the study, however at the end of the study when forward flow rates increased, SO42--S concentrations increased to 32 mg L-1 for R-2 and 40 mg L-1 for FF-2. Similar performance was observed in the FF system as the bench scale reactor tests. The second part of the research focused on the findings from a study of a Particulate Pyrite Autotrophic Denitrification (PPAD) process that uses pyrite as the electron donor and nitrate as the terminal electron acceptor in upflow packed bed bioreactors. The advantages of using pyrite as an electron donor for denitrification include less sulfate production and lower alkalinity requirements compared with SOD. The low alkalinity consumption of the PPAD process led to comparison of PPAD performance with and without oyster shell addition. Two columns were operated side-by-side, one packed with pyrite and sand only (P+S), while another one was packed with pyrite, sand and oyster shell (P+S+OS). Sand was used as a nonreactive biofilm carrier in the columns. My contribution to this research was to carry out Scanning Electron Microscopy-Energy-Dispersive X-Ray Spectroscopy (SEM-EDS) analysis to support the hypothesis that oyster shell contributes to nitrogen removal because it has a high capacity for biofilm attachment. SEM analysis showed that oyster shell has a rough surface, supported by its high specific surface area, and that there was more biofilm attached to oyster shell than pyrite or sand in the influent to the column. EDS results showed a decrease in atomic percentages for pyrite sulfur in the effluent of both columns (59.91% ± 0.10% to 53.94% ± 0.37% in P+S+OS column and to 57.61% ± 4.21% in P+S column). This finding indicated that sulfur was oxidized more than iron and/or the accumulation of iron species on the pyrite surface and supports the coupling of NO3- reduction with pyrite oxidation.

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Rasheed, Adamu Abubakar. "Advances in the use of aerobic sequencing batch reactors for biological wastewater treatment." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=233113.

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The overall aim of this research was to contribute to the optimisation of aerobic wastewater treatment processes in sequencing batch reactors, by investigating the performance of the process with real and model wastewaters in order to achieve the highest possible reduction of influent COD with the minimum reactor volume and oxygen consumption. Six industrial wastewaters from the food and drink companies were treated in lab-scale aerobic sequencing batch reactors (SBRs) inoculated with soil and monitored for COD and total suspended solids (TSS) removal. The results showed high COD removal efficiencies for all the wastewaters, in the range of 64-95 %. Extended aeration tests were carried out on the reactor effluents and the results indicated that the residual soluble COD was not further biodegradable. This indicates that the soluble BOD removal in the reactors was virtually 100 %. The biodegradation efficiency was investigated over two values of the solids retention time (SRT) and the performance of the reactors was essentially unaffected by the SRT (in the range of 7-18 days considered in this study). This means that very good COD removal can be achieved at relatively lower SRT, with potential savings in capital and operating costs. The removal of TSS for the wastewaters was not satisfactory, largely due to the low food to microorganism (F/M) ratios (0.13-0.29 kg COD/kg biomass.day) in the reactors. Three batch tests at different initial substrate to biomass (So/Xo) ratios were carried out on each of the two industrial wastewaters for kinetic characterisation of the wastewaters. Oxygen uptake rate (OUR) was measured during the tests and the OUR profiles were used for the estimation of the kinetic parameters using a mathematical model consisting of substrate hydrolysis, biomass growth and endogenous metabolism. The results showed large variations with regards to the values of the parameters for each wastewater due to day-to-day variability in the biomass's response to substrate utilisation. For the two industrial wastewaters, the hydrolysis rate constant (kh) and half saturation constant for slowly biodegradable substrate (KX) were found to be in the range of 2.21-14.8 kg COD/kg biomass.day and 0.006-0.45 kg COD/kg biomass respectively. The maximum growth rate (μmax) and the half saturation rate constant for readily biodegradable substrates (KS) ranged between 1.21-7.3 day-1 and 0.004-0.89 kg COD/m3 respectively. The biomass growth yield (YX/S) and the endogenous metabolism coefficient (b) were found to be 0.3-0.57 kg biomass/kg COD and 0.001-0.41 day -1 respectively. The hydraulic retention time (HRT) and SRT were optimised in order to minimise the SBR volume and maximise the organic loading rate (OLR) of the SBR process. Two model wastewaters, glucose and ethanol, were used in the study. An experiment of eleven different SBR runs (HRT in the range of 0.25-4 days and SRT of 1-65.3 days) was carried on the glucose wastewater. Nine different SBR runs were carried out on ethanol wastewater (HRT in the range of 0.5-4 days and SRT of 1-73.6 days). The minimum HRT and SRT values for the successful operation for glucose wastewater treatment were 0.25 days and 3.1 days respectively while the minimum HRT and SRT for ethanol were 0.5 days and 4.9 days respectively. The highest corresponding OLR values from the minimum HRT and SRT which gave satisfactory process performance were 4.28 g COD/l.day and 4.14 g COD/l.day for glucose and ethanol wastewaters respectively, which are among the highest OLRs reported in the literature for aerobic conventional dispersed-growth processes. The calculated oxygen consumption and biomass production were found to depend on the SRT as well as the OLR, where in general, oxygen consumption increased while biomass production decreased at higher OLR. Batch tests were also carried out on the two model wastewaters for kinetic characterisation. The kinetic parameters for glucose wastewater were: 1.07-4.79 day -1 for μmax, 0.24-0.45 kg COD/m3 for KS, 0.04-0.1 day-1 and 0.47-0.6 kg biomass/kg COD for b and YX/S respectively. For ethanol wastewater, the kinetic parameters were: 0.99-2.3 day -1 for μmax, 0.001-0.04 kg COD/m3 for KS, 0.05-0.2 day-1 and 0.38-0.51 kg biomass/kg COD for b and YX/S respectively. A new mathematical model and procedure to calculate the periodic steady state of the SBR using a kinetic model of the biological process and values of the kinetic parameters was developed. This new procedure allows the direct calculation of the steady state profiles of biomass and substrate in the SBR without calculating the dynamics of the system from start up to steady state. The numerical accuracy of the procedure was discussed and the model was applied to show the effect of the operating parameters (SRT, HRT, length of the phases and number of cycles) on the steady state performance in terms of biomass and substrate concentrations. It was also shown how the model can be used for various applications like: optimisation of operating parameters for a minimum reactor volume; simulation of the competition between filamentous and floc-forming bacteria for bulking control; and calculation of the minimum volumetric mass-transfer coefficient required to maintain a desired oxygen concentration. In the end, the periodic steady state of the SBR was simulated for the industrial and model wastewaters at various values of the operating conditions (e.g. HRT, SRT, number of cycles) using the developed SBR model with values of kinetic parameters obtained from the various batch tests. The predicted model performance in terms of effluent quality and biomass concentration was compared with experimental results achieved during the treatment of the wastewaters. The simulation gave very good prediction of the extent of substrate removal for all the wastewaters. However, the prediction was not very accurate for biomass concentration. The study indicated that a good model prediction in terms of biomass production is strongly dependent on the values of the kinetic parameters especially b and YX/S.

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Pratt, Steven. "The development of the TOGA sensor for the study of biological wastewater treatment systems /." [St. Lucia, Qld.], 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17251.pdf.

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15

Lishman, Lori-Ann. "The influence of substrate and temperature on biological nitrogen removal in wastewater treatment systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0028/NQ30622.pdf.

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16

Hodkinson, Brenden James. "The sewage treatment capability of non-backwash biological aerated filter systems for small communities." Thesis, University of Portsmouth, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368839.

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Biological Aerated Filters (BAFs) are wastewater treatment systems which contain support media for biofilm development and provide oxygen at the base of the reactor to sustain aerobic microbial treatment processes. The aims of this study were to characterise and quantify the treatment capability of non-backwash BAFs used in small sewage treatment works, and therefore establish design recommendations. Three full scale trial BAFs, a field operational small sewage treatment plant, and a full scale aeration testing facility were studied. The trial BAFs, with simulated secondary settlement, provided carbonaceous stabilisation under various hydraulic loadings and airflow rates. Nitrification showed no relationship with airflow rate, but was inhibited at high hydraulic loadings. Sludge production in the BAFs was less at higher airflow rates, due to improved stabilisation of organic solids. Media specific surface area had little effect on treatment performance. Downflow operation generally provided better treatment than upflow operation, with high levels of suspended solids stabilisation, considered a function of longer residence times. The mean BAF residence times determined empirically were considerably shorter than the design residence times, and may have inhibited treatment potential. The oxygen transfer efficiency (OTE) of coarse bubble diffusers was enhanced in a simulated BAF, due to the effects of the support media. Fine bubble diffuser OTE was inhibited by the media. Coarse diffusers may be more appropriate than fine diffusers for small non-backwash BAFs, a function of performance and cost efficiency. A small packaged sewage treatment plant incorporating BAFs produced a well nitrified effluent with reasonable organic stabilisation, and showed little diurnal or seasonal variation in effluent quality. The plant compared well to other small sewage treatment systems, providing treatment in a small footprint. Design recommendations for non-backwash BAFs and small sewage treatment plants incorporating BAFs have been established, based on the knowledge gained during this study. It has been demonstrated that non-backwash BAFs are appropriate for use in small sewage treatment works.

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17

Lakshminarasimman, Meanakshisek Narasimman. "Evaluating the Fate Mechanisms of Trace Organic Compounds in Biological Nutrient Removal Treatment Systems." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1479818400753707.

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18

Gomez-Rivera, Francisco. "Exploration of Biological Treatment Systems for the Removal of Persistent Landfill Leachate Contaminants and Nanoparticles." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/145311.

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The integrity of groundwater sources is constantly threatened by contaminant plumes generated by accidental gasoline leakages and leachates escaping landfills. These plumes are of concern due to their proven toxicity to living organisms. Aromatic and chlorinated hydrocarbons, volatile fatty acids, phenols, and ammonia have been found in these leachates. In addition, benzene, toluene, and xylenes (BTX) are major components of gasoline. The lack of oxygen in groundwater makes anaerobic bioremediation desired for the treatment of groundwater contaminated with BTX and chlorinated solvents. With the objective of finding microorganisms capable of BTX and cis-dichloroethylene (cis-DCE) degradation under anaerobic conditions for their use in permeable reactive barriers, different inocula were tested in batch experiments. Toluene was rapidly degraded by several inocula in the presence of alternative electron acceptors. Benzene and m-xylene were eliminated by few of the inocula tested after incubation periods ranging from 244 to 716 days. cis-DCE was highly recalcitrant as no degradation was observed over 440 days. Biological processes have been successfully applied for the treatment of landfill leachates as well. In an effort to provide an effective and economical alternative, an anaerobic-aerobic system was evaluated using a synthetic media simulating the organic and ammonia content of real leachates. The removal of the organic content reached 98% in an upflow anaerobic sludge blanket reactor, and resulted in the formation of methane. During the aerobic process, in an innovative down-flow sponge reactor, ammonia was highly transformed to nitrite and nitrate. Complete nitrification was eventually achieved.The capacity of current wastewater treatment plants for removing nanoparticles has been questioned during the last years. Nanoparticles have been incorporated into numerous applications and their presence in wastewater seems to be inevitable. A laboratory-scale secondary treatment system was set-in to study the behavior of cerium and aluminum oxide nanoparticles during wastewater treatment. The nanoparticles were highly removed, suggesting that secondary treatment is suitable for their elimination. The removal of these nanoparticles was influenced by the pH and organic content of the wastewater. Aluminum nanoparticles proved to be toxic; however the performance of the system for eliminating the organic content was recovered over time.

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19

Tezel, Ulas. "Fate and effect of quaternary ammonium compounds in biological systems." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28229.

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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Pavlostathis, Spyros G.; Committee Member: Huang, Ching-Hua; Committee Member: Hughes, Joseph B.; Committee Member: Sobecky, Patricia A.; Committee Member: Spain, Jim C.

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20

Tingey, David. "Estimation and control of some classes of dynamical systems with application to biological wastewater treatment." Thesis, Northumbria University, 2007. http://nrl.northumbria.ac.uk/1222/.

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It is well-known that there are no general approaches for observer and controller design for nonlinear systems. Instead, focus is placed upon design for classes of systems. On the other hand, a wide variety of dynamical systems belong to the class of state-affine systems. Amongst these are biological wastewater treatment processes, which are essential in order to prevent pollution in the environment and prevent disease in the consumption of recycled water. An interesting aspect found in biological wastewater treatment systems, and many typical industrial processes, are time-delays. In almost all systems there are time-delays and nonlinearities and it is not surprising that time-delay and nonlinear systems have received a great deal of attention in mathematics and control engineering. This project introduces new methodologies for the design of controllers and observers for a class of state-affine systems and a class of linear time-delay systems. Firstly, new observable and controllable canonical forms are introduced. These are then used to establish new controller and observer design methodologies for a class of state¬affine systems. In particular, an adaptive observer design is established. The methodologies are simple since they are based upon linear techniques. Secondly, a full-state controller and a separation principle are established for a class of single-input single-output linear time-delay systems. The designs are based on a new stability criterion and are derived from first principles. Finally, the new observer design methodology for the class of state-affine systems is used to produce observers for the estimation of biomass concentration in a biological wastewater treatment bioreactor. The observers are applied in theory and in simulation, where a full and a partial knowledge of the kinetic rate of reaction of biomass are considered. In addition, the performances are shown both in the absence and in the presence of measurement noise for a variety of influent flow characteristics.

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21

Payne, Karl A. "Mathematical and Numerical Modeling of Hybrid Adsorption and Biological Treatment Systems for Enhanced Nitrogen Removal." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7702.

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High nutrient loading into groundwater and surface water systems has deleterious impacts on the environment, such as eutrophication, decimation of fish populations, and oxygen depletion. Conventional onsite wastewater treatment systems (OWTS) and various waste streams with high ammonium (NH4+) concentrations present a challenge, due the inconsistent performance of environmental biotechnologies aimed at managing nutrients from these sources. Biological nitrogen removal (BNR) is commonly used in batch or packed-bed reactor configurations for nitrogen removal from various waste streams. In recognition of the need for resource recovery, algal photobioreactors are another type of environmental biotechnology with the potential for simultaneously treating wastewater while recovering energy. However, irrespective of the technology adopted, outstanding issues remain that affect the consistent performance of environmental biotechnologies for nitrogen removal and resource recovery. In OWTS, transient loading can lead to inconsistent nitrogen removal efficiency, while the presence of high free ammonia (FA) can exert inhibitory effects on microorganisms that mediate transformation of nitrogen species as well as microalgae that utilize nitrogen. Therefore, to overcome these challenges there have been experimental studies investigating the addition of adsorption and ion exchange (IX) media that can temporarily take up specific nitrogen ions. Bioreactors comprised of microorganisms and adsorption/IX media can attenuate transient loading as well as mitigate inhibitory effects on microorganisms and microalgae; however, the interplay between physicochemical and processes in these systems is not well understood. Therefore, the main objective of this dissertation was to develop theoretical and numerical models that elucidate the complex interactions that influence the fate of chemical species in the bioreactors. To achieve this objective and address the issues related to improving the understanding of the underlying mechanisms occurring within the environmental biotechnologies investigated, the following three research studies were done: (i) experimental and theoretical modeling studies of an IX-assisted nitrification process for treatment of high NH4+ strength wastewater (Chapter 3), (ii) theoretical and numerical modeling of a hybrid algal photosynthesis and ion exchange (HAPIX) process for NH4+ removal and resource recovery (Chapter 4), and (iii) mathematical and numerical modeling of a mixotrophic denitrification process for nitrate (NO3-) removal under transient inflow conditions (Chapter 5). The experimental results for the IX-assisted nitrification process showed that by amending the bioreactor with zeolite, there was a marked increase in the nitrification rate as evidenced by an increase in NO3– production from an initial concentration of 3.7 mg-N L-1 to 160 mg-N L-1. This increase is approximately an order of magnitude greater than the increase in the reactor without chabazite. Therefore, the experimental studies provided support for the hypothesis that IX enhances the nitrification process. To garner further support for the hypothesis and better understand the mechanisms in the bioreactor, a novel mathematical model was developed that mechanistically describes IX kinetics by surface diffusion coupled with a nitrification inhibition model described by the Andrews equation. The agreement between the model and data suggests that the mathematical model developed provides a theoretically sound conceptual understanding of IX-assisted nitrification. A model based on the physics of Fickian diffusion, IX chemistry, and algal growth with co-limiting factors including NH4+, light irradiance, and temperature was developed to describe a batch reactor comprised of microalgae and zeolite. The model can reproduce the temporal history of NH4+ in the reactor as well as the growth of microalgae biomass. The mathematical model developed for the HAPIX process balances between simplicity and accuracy to provide a sound theoretical framework for mechanisms involved. In OWTS, transient inflow conditions have an influence on the performance of environmental biotechnologies for nitrogen removal. Prior experiments have shown that for denitrification, a tire-sulfur hybrid adsorption and denitrification (T-SHAD) bioreactor consistently removes nitrogen under varying influent flow and concentration conditions. To enhance the understanding of the underlying mechanisms in the T-SHAD bioreactor, a mathematical model describing mass transport of NO3- and SO42- in the aqueous phase and mixotrophic denitrification was developed. Additionally, a numerical tool to solve the mathematical model was implemented and compared to previously conducted experiments. Results from the numerical simulations capture the trend of the experimental data showing approximately 90% NO3- -N removal under varying flow conditions. Moreover, the model describes the effluent characteristics of the process showing a transient response in correspondence the changes in fluid velocity. The new tools developed provide new insight into the underlying mechanisms of physical, chemical, and biological processes within these bioreactors. The tools developed in this dissertation have a potential broad impact in environmental biotechnology for wastewater treatment in on-site systems, for treatment of high strength wastewater, and can be extended easily for stormwater management systems aimed at mitigating high nutrient loading to the environment.

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22

Mbwele, Lydia Ambakisye. "Microbial Phosphorus Removal in Waste Stabilisation Pond Wastewater Treatment Systems." Licentiate thesis, KTH, School of Biotechnology (BIO), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3876.

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Waste Stabilisation Ponds (WSPs) are characterised by low phosphorus (P) removal capacity. Heterotrophic bacteria are principal microbial agents in WSPs in addition to algae. As treatment proceeds in WSPs, algal growth increases and pH rises, this has lead to believe that P removal is mainly through sedimentation as organic P algal biomass and precipitation as inorganic P. In activated sludge treatment plants (AS), microbial P removal has been improved and is termed as enhanced biological phosphorus removal. There was a need to establish whether it was possible to enhance P removal in WSPs. A performance assessment of pond system at the University of Dare s Salaam (UDSM), Tanzania, has shown that 90% of the P removed was in the primary pond (facultative) and the rest in the maturation pond (aerobic).

In these studies, a pure strain A. hydrophyla was isolated from an activated sludge wastewater treatment plant in Sweden. This plant has a train that functions with enhanced biological phosphorus removal. The strain was tested for P uptake in minimal media supplemented with glucose, succinate or acetate, grown aerobically and anaerobically/aerobically. This strain was able to take up P without having been subjected to the anaerobic phase. It was observed that P uptake was enhanced after the anaerobic phase with media supplemented with glucose, but not with succinate or acetate. Phosphorus uptake repeatedly followed the bacterial growth pattern with correlation coefficients of more than 95%. Therefore P removal has a direct correlation with bacterial growth.

Two isolates Acinetobacter sp. (isolated from the primary facultative pond) and E .coli (isolated from the maturation pond) were obtained from a tropical WSP treatment system at the UDSM. They were subjected to aerobic P uptake experiment similar to those of A.hydrophyla. The uptake per unit absorbance of bacterial growth was found to be comparable to that of A.hydrophyla, isolated from AS. These results showed that heterotrophic activity is important in WSPs. It is possible to enhance P removal in these systems by designing the primary ponds for maximum heterotrophic activity and probably enrichment.

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23

Westensee, Dirk Karl. "Post-treatment technologies for integrated algal pond systems." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1018180.

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Integrated Algae Pond Systems (IAPS) are a derivation of the Oswald designed Algal Integrated Wastewater Pond Systems (AIWPS®) and combine the use of anaerobic and aerobic bioprocesses to effect wastewater treatment. IAPS technology was introduced to South Africa in 1996 and a pilot plant designed and commissioned at the Belmont Valley WWTW in Grahamstown. The system has been in continual use since implementation and affords a secondarily treated water for reclamation according to its design specifications which most closely resemble those of the AIWPS® Advanced Secondary Process developed by Oswald. As a consequence, and as might be expected, while the technology performed well and delivered a final effluent superior to most pond systems deployed in South Africa it was unable to meet The Department of Water Affairs General Standard for nutrient removal and effluent discharge. The work described in this thesis involved the design, construction, and evaluation of several tertiary treatment units (TTU') for incorporation into the IAPS process design. Included were; Maturation Ponds (MP), Slow Sand Filter (SSF) and Rock Filters (RF). Three MP's were constructed in series with a 12 day retention time and operated in parallel with a two-layered SSF and a three-stage RF. Water quality of the effluent emerging from each of these TTU's was monitored over a 10 month period. Significant decreases in the chemical oxygen demand (COD), ammonium-N, phosphate-P, nitrate-N, faecal coliforms (FC) and total coliforms (TC) were achieved by these TTU's. On average, throughout the testing period, water quality was within the statutory limit for discharge to a water course that is not a listed water course, with the exception of the total suspended solids (TSS). The RF was determined as the most suitable TTU for commercial use due to production of a better quality water, smaller footprint, lower construction costs and less maintenance required. From the results of this investigation it is concluded that commercial deployment of IAPS for the treatment of municipal sewage requires the inclusion of a suitable TTU. Furthermore, and based on the findings presented, RF appears most appropriate to ensure that quality of the final effluent meets the standard for discharge.

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24

Palazolo, Paul Joseph. "Use of genetic algorithms in bounded search for design of biological nitrification/denitrification waste treatment systems." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/32777.

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25

Asiedu, Kofi. "Evaluating Biological Treatment Systems: (i) Moving Bed Biofilm Reactor versus Biological Aerated Filtration, and (ii) Sulfide-Induced corrosion in Anaerobic Digester Gas Piping." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35156.

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The research presented in this report is in two sections. Section I involved the performance of a moving bed biofilm reactor (MBBR) versus a biological aerated filtration (BAF) and Section II involved study on causes of deposition in anaerobic digester gas piping.

The first section evaluated and compared the performance of a laboratory-scale MBBR and BAF for organic carbon and suspended solids removal. A kinetic study was also performed on the MBBR to evaluate the system performance. The purpose was to recommend one of the systems for the Force Provider project, which provides a containerized "city" for the U.S. Army. The effluent criteria against which the systems were evaluated were total 5-day biochemical oxygen demand (TBOD5) and total suspended solids (TSS) of 30 mg/L each. The report is based on a 5-month laboratory -scale study of the two reactors.

The MBBR performance depended on the percent of media provided in the reactor and the organic loading. At a media volume, which displaced the reactor volume by 40 % (heretofore called 40 % media volume), and surface area loading rate (SALR) of 20 g BOD5/m2-d, the system performance deteriorated with time. At 40 % media volume and SALR below 15 g BOD5/m2-d, the system performance improved but still did not meet effluent criteria or average. TBOD5 reduction was generally poor (approximately 50 %). Soluble BOD5 (SBOD5) concentrations were frequently below 30 mg/L and TSS concentrations were often higher than influent TSS. Overall, TSS wastage from the system (both effluent TSS and intentional wastage) averaged 0.032 kg/d.

BAF system performance was excellent for TBOD5, CBOD5, SBOD5 and TSS removal, and were consistently less that 30 mg/L. Overall TSS wastage from the BAF (both via effluent and backwash) average 0.027 kg/d and was 16 % less than for the MBBR. Based on demonstrated performance, the BAF was the only viable reactor for the project.

Section II of the report focused on possible causes of deposition in an anaerobic digester gas piping at a local wastewater treatment facility (Peppers ferry regional wastewater treatment facility).

Industrial waste input to the treatment facility has increased lately and accounts for 40 % of the plant's wastewater inflow. An industry in Pulaski, VA, Magnox Inc. generates and disposes highly concentrated sodium sulfate, (70,000 mg/L) which is a by-product of its activities, to PFRWTF wastewater influent stream. As a result of Magnox industrial waste input, a pilot study was carried out to determine the effect of its waste on the activated sludge treatment units. Results indicated that Magnox industrial waste input would not have adverse effect on the aeration basins. However production of H2S, which can have effect on the anaerobic digester was reported (Olver Inc., 1995). Field analysis of data reported by Olver Inc. (2000) showed that H2S concentration in PFRWTF anaerobic digester gas was rising. X-ray photoelectron spectroscopy analysis of deposits found in the digester pipe together with results obtained from the laboratory-scale study revealed that iron and sulfur played a role in the deposition in the digester gas pipe. The laboratory scale study revealed that ferrous ion in the digester feed possibly precipitated over 90 % of the hydrogen sulfide gas produced in the digester, thus protecting the digester from adverse effects caused by hydrogen sulfide.

Master of Science

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26

Scherman, Patricia Ann (neé Goetch). "The microbial production of polyphenol oxidase enzyme systems and their application in the treatment of phenolic wastewaters." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1004108.

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Phenolic compounds are a group of organic chemicals present in the wastewaters of many synthetic industrial processes. Due to their extreme toxicity to man and animals, and deleterious impact on the environment, a range of techniques exist for the effective treatment and disposal of these pollutants. Biological degradation using microbial enzymes presents a valuable alternative to conventional wastewater treatment systems. This research was therefore initiated to investigate the polyphenol oxidase enzyme system and the feasibility of its application for effluent treatment and studies in organic solvents. The enzyme system is widely distributed in nature, with Agaricus bisporus (the common mushroom) being the best known producer. Biochemical investigations of the enzyme system were therefore carried out using this extract. A screening programme was initiated to identify microbial polyphenol oxidase producers which could be cultured in liquid media, thereby enabling the production of large quantities of enzyme in fermentation systems. Extensive growth optimization and enzyme induction and optimization studies were carried out on selected cultures. A number of good producers were isolated, namely a bacterial culture designated AECI culture no. 26, Streptomyces antibioticus, Streptomyces glaucescens and a manipulated strain, Streptomyces lividans (pIJ702). Enzyme production by Agaricus bisporus mycelia was optimized in deep-liquid culture; enzyme extracts showed high phenol removal efficiencies. Streptomyces antibioticus, Streptomyces glaucescens, Streptomyces lividans (pIJ702) and AECI culture no. 26 whole cells were also investigated for phenol-removing ability in simulated phenolic effluents. The use of whole cells reduces enzyme inactivation and instability due to the protection of the enzyme system within the cell. All cultures showed improved removal efficiencies in phenolic growth media. These results strongly suggest their use for phenol removal in continuous systems.

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27

Fortin, Nathalie. "Molecular characterization of dechlorination potential in kraft pulp mill effluent treatment systems." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27317.

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Many low molecular weight chlorinated organic compounds produced by the pulp and paper industry during kraft bleaching of the wood pulp are toxic. Mass balance studies suggest that mineralization of chlorinated organics is occurring in pulp and paper mill wastewater treatment systems. To understand the nature of dechlorination activity, molecular tools such as oligonucleotide primers and corresponding DNA probes were developed to monitor the presence of microorganisms possessing key genes (dehalogenases) responsible for the degradation of chloroaliphatic organics in kraft pulp mill effluent treatment systems. Oligonucleotide primers designed from the coding sequence of known dehalogenases and a methane monooxygenase gene, which is known to catalyze dehalogenation reactions, were used for polymerase chain reaction (PCR) analysis, using genomic DNA extracted from dehalogenating bacterial isolates and total community DNA extracted from water and sediments of lagoon treatment systems. PCR amplification with dhlB oligonucleotide primers, designed from the haloacid dehalogenase of Xanthobacter autotrophicus, revealed the presence of dehalogenase genes in both aerated lagoons and stabilization basins. Similar results were obtained with mmoX primers designed from the methane monooxygenase gene of Methylococcus capsulatus. DNA sequence analysis of several PCR fragments showed significant similarity to known dehalogenase genes. The molecular tools developed in this study revealed the presence of different types of microorganisms with dechlorination potential in the microbial community of pulp mill effluents.

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28

Nelson, Mark. "Conceptual design of zero discharge and safe discharge biological wastewater treatment systems using fast-growing wetland trees." Thesis, The University of Arizona, 1995. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1995_341_sip1_w.pdf&type=application/pdf.

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Miriyala, Amulya. "Impact of Recirculating Nitrified Effluent on the Performance of Passive Onsite Hybrid Adsorption and Biological Treatment Systems." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7697.

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Approximately 25% of households in the U.S. treat their wastewater onsite using conventional onsite wastewater treatment systems (OWTS). These systems typically include a septic tank or a series of septic tanks followed by a soil absorption system. They effectively remove biochemical oxygen demand (BOD), total suspended solids (TSS), fats and grease but are not designed to remove significant amounts of nitrogen. High nitrogen loading to coastal and ground waters can be dangerous to aquatic life and public health. Hence, there is a need for advanced onsite wastewater treatment systems that can effectively remove nitrogen. Making enhanced nitrogen removal for OWTS as our primary goal, a laboratory scale Hybrid Adsorption and Biological Treatment Systems (HABiTS) was developed and upon observation of its effective nitrogen removal capacity, a pilot demonstration study with two side-by-side HABiTS, one with recirculation and one without recirculation (only forward flow) were constructed and tested at the Northwest Regional Water Reclamation Facility in Hillsborough County (Florida). HABiTS employ biological nitrogen removal and ion exchange for effective nitrogen removal. HABiTS is a two-stage process which uses nitrification for the oxidation of ammonium to nitrate and ion exchange for ammonium adsorption that helps buffer transient loading and also acts as a biofilm carrier in its stage 1 biofilter and it uses tire-sulfur hybrid adsorption denitrification (T-SHAD) in its stage 2 biofilter. These sulfur pellets help promote sulfur oxidation denitrification (SOD) and tire chips are used for nitrate adsorption during transient loading conditions, as biofilm carriers for denitrifying bacteria, and can also be used as organic carbon source to promote heterotrophic denitrification because they leach organic carbon. For this research, HABiTS without recirculation is considered as the control system and the performance of HABiTS with recirculation was tested for its ability to further enhance nitrogen removal from HABiTS. Nitrified effluent recirculation is a common strategy employed in wastewater treatment for enhanced nitrogen removal. It is the reintroduction of semi-treated wastewater to pass through an anoxic pre-treatment chamber to achieve better quality effluent. Recirculation is said to improve and consistently remove nitrogen at any hydraulic loading rate and/or nitrogen concentration. This is because of the dilution of high BOD septic tank effluent with nitrified effluent which lowers COD:TKN ratio and also improves mass transfer of substrates in the stage 1 biofilter. Recirculation also provides some pre-denitrification in the pre-treatment chamber, thereby reducing nitrogen load on the system. The HABiTS with recirculation (R) was run at 1:1 ratio of nitrified effluent recirculation rate to the influent flow rate for 50 days, and at 3:1 ratio for the remaining period of this research (200 days). The forward flow system (FF) was run under constant conditions throughout the research and comparisons between the two systems were made for different water quality parameters (pH, DO, conductivity, alkalinity, TSS, chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and various nitrogen species). The final effluent ammonium results showed that the system with recirculation removed consistently > 80% NH4+-N during 1:1 and 3:1 recirculation ratios whereas the forward flow system achieved 57% removal. Further, an average of 81% total inorganic nitrogen (TIN) removal from the system influent was seen in the recirculation system’s final effluent when compared to an average of 55% in forward flow system’s final effluent. This research explains in detail, the impact of nitrified effluent recirculation on enhanced nitrogen removal in onsite systems and the results presented in this thesis proved that nitrified effluent recirculation provides promising enhanced nitrogen removal in an onsite wastewater treatment system.

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30

Hajaya, Malek Ghaleb. "Fate and effect of quaternary ammonium antimicrobial compounds on biological nitrogen removal within high-strength wastewater treatment systems." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41113.

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High strength wastewater (HSWW) generated in food processing industries is characterized by high organic carbon and nitrogen content, and thus high oxygen demand. Biological nitrogen removal (BNR) is a technology widely used for the treatment of HSWW. Food processing facilities practice sanitation to keep food contact surfaces clean and pathogen-free. Benzalkonium chlorides (BACs) are cationic quaternary ammonium antimicrobial compounds (QACs) common in industrial antimicrobial formulations. BAC-bearing wastewater generated during sanitation applications in food processing facilities is combined with other wastewater streams and typically treated in BNR systems. The poor selectivity and target specificity of the antimicrobial BACs negatively impact the performance of BNR systems due to the susceptibility of BNR microbial populations to BAC. Objectives of the research were: a) assessment and quantification of the inhibitory effect of QACs on the microbial groups, which mediate BNR in HSWW treatment systems while treating QAC-bearing HSWW; b) evaluation of the degree and extent of the contribution of QAC adsorption, inhibition, and biotransformation on the fate and effect of QACs in BNR systems. A laboratory-scale, multi-stage BNR system was continuously fed with real poultry processing wastewater amended with a mixture of three benzalkonium chlorides. The nitrogen removal efficiency initially deteriorated at a BAC feed concentration of 5 mg/L due to complete inhibition of nitrification. However, the system recovered after 27 days of operation achieving high nitrogen removal efficiency, even after the feed BAC concentration was stepwise increased up to120 mg/L. Batch assays performed using the mixed liquors of the BNR system reactors, before, during, and post BAC exposure, showed that the development of BAC biotransformation capacity and the acquisition of resistance to BAC contributed to the recovery of nitrification and nitrogen removal. Kinetic analysis based on sub-models representing BNR processes showed that BAC inhibition of denitrification and nitrification is correlated with BAC liquid-phase and solid-phase concentrations, respectively. Simulations using a comprehensive mathematical BNR model developed for this research showed that BAC degradation and the level of nitrification inhibition by BAC were dynamic brought about by acclimation and enrichment of the heterotrophic and nitrifying microbial populations, respectively. The fate and effect of BACs in the BNR system were accurately described when the interactions between adsorption, inhibition, and resistance/biotransformation were considered within the conditions prevailing in each reactor. This work is the first study on the fate and effect of antimicrobial QACs in a continuous-flow, multi-stage BNR system, and the first study to quantify and report parameter values related to BAC inhibition of nitrification and denitrification. Results of this study enable the rational design and operation of BNR systems for the efficient treatment of QAC-bearing wastewater. The outcome of this research provides information presently lacking, supporting the continuous use of QACs as antimicrobial agents in food processing facilities, when and where needed, while avoiding any negative impacts on biological treatment systems and the environment.

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31

Scott, Robert Nigel. "Algal and related biological studies of reservoirs in South Wales with reference to management of water treatment systems." Thesis, Cardiff University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238187.

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Rodríguez-Caballero, Adrián. "Fugitive green-house gas emissions during biological wastewater treatment: investigating sources and mitigation strategies in laboratory and full-scale systems." Doctoral thesis, Universitat de Girona, 2015. http://hdl.handle.net/10803/361394.

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The exponential increase of the atmospheric concentration of green-house gases due to human activities is responsible for the acceleration of global warming and climate change. Recently, scientific studies have pointed at wastewater treatment systems as relevant sources of fugitive green-house gases (GHGs) such as nitrous oxide (N2O) and methane (CH4). Nitric oxide (NO) can also be emitted during wastewater treatment, and it is a potent ozone-depleting compound and a precursor of N2O. Due to the high global warming potential of N2O and CH4, emission of these gases (even at low levels) may be relevant and increase severely the overall carbon footprint of a wastewater treatment system.
L’acceleracio en l’escalfament global i el canvi climatic son consequencia de l’increment exponencial de la concentracio de gasos d’efecte hivernacle en l’atmosfera degut, en part, a l’activitat humana. Estudis cientifics publicats recentment apunten a alguns sistemes de tractament d’aigues residuals com a fonts rellevants de gasos d’efecte hivernacle com l’oxid nitros (N2O) i el meta (CH4). A mes, l’oxic nitric (NO), un potent destructor de la capa d’ozo a mes de ser un precursor del N2O, tambe pot ser emes durant el tractament d’aigues residuals. Degut a l’alt potencial d’escalfament atmosferic del N2O i el CH4, l’emissio d’aquests gasos (inclus a baixes concentracions) pot ser rellevant, incrementant de forma significativa la petjada ecologica dels sistemes de tractament d’aigues residuals.

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Ribera, Pi Judit. "Hybrid systems for wastewater treatment in the framework of circular economy : coupling biological and membrane technologies for a sustainable water cycle." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/668391.

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The increasing water demand coupled to the depletion of natural water sources has raised the need to investigate and develop in wastewater treatment and reuse. Even more, the application of circular economy principies to water cycle has highlighted the need to see wastewater as a source of water and resources. Therefore, hybridization of already developed technologies can help achieve circular economy goals. Moreover, these hybrid systems that take the best of each technology are capable to gain to the limitations of current conventional treatments. Thus, in this thesis, different hybrid systems have been developed and tested (at bench and pilot scales) for wastewater treatment, both urban and industrial. On one hand, three upflow anaerobic sludge blanket (UASB) reactors with different configurations: flocculent biomass, flocculent biomass and membrane solids separation and granular biomass and membrane solids separation (UASB-AnMBR), were operated to compare start-up, solids hydrolysis and effluent quality. The challenges of this work were both the low temperature and the low COD content. A really quick start-up was observed for the three reactors and was attributed to the previous acclimation of the seed sludge. The UASB configurations with membrane retained the solids in the reactor increasing solids hydrolysis efficiency. Moreover, flocculent biomass promoted slightly higher hydrolysis than granular one. Therefore, a configuration based on flocculent UASB-AnMBR was appropriate for the treatment of urban wastewater with low COD content at 10°C. ' On the other hand, a single-stage AnMBR for the treatment of cheese whey and its co-digestion with cattle slurry was investigated with the aim of potentially recovering water and energy. High COD removal (91% ± 7%) was achieved with a biogas production of 0.2-0.9 m3 biogas/kg COD removed. Therefore, high energy recovery could be obtained when using this process with a mean value of 2.4 kWh/kg COD removed. Although energy recovery was directly validated, severallimitations were detected regarding water reuse. Those limitations comprised high salt concentration in the permeate, which should be removed prior to its reuse. Moreover, petrochemical wastewater pre-treatment was optimised with the final objective of water recycling. lt consisted in a coagulation-flocculation (CF) step followed by a moving bed biofilm reactor (MBBR) aimed to decrease suspended solids (SS) and organic content. In this case, only the first part of the hybrid system was optimised, membrane units were not included in this work. CF tests showed a decrease in wastewater turbidity but no significant DOC removal. Wastewater was then treated by MBBR. In MBBR, high sCOD removal efficiency (80-90%) was maintained. The MBBR proved to be also effective when treating raw wastewater as well as when feed wastewater effluent proportions were changed. The obtained results showed that MBBR was a suitable technology for petrochemical wastewater pre-treatment. Finally, a novel treatment strategy for landfillleachate aimed to decrease its environmental impact was studied. The system consisted in a membrane bioreactor (MBR) pre-treatment aimed to remove COD, N and SS. lt was followed by a combined reverse osmosis-electrodialysis reversa! (RO-EDR) treatment aimed to remove salts and decrease brine volume. MBR decreased inorganic carbon by 92 ± 8% and achieved N removal of 85%. RO achieved a recovery of 84% and rejections of above 95%. EDR unit treating RO brine achieved a recovery of 67%. Thus, average recovery of the whole system was above 90%. lt is important to highlight that end-of-life RO regenerated membranes were used in this study. This fact, together with the low volume of brine (<10%) helped decrease the environmental impact of leachate treatment. Hence, this thesis was conducted from an applied research approach, aimed to reduce the gap between basic technology development and industrial implementation.
La creixent demanda d'aigua i l'esgotament de les fonts naturals ha generat la necessitat d'investigar i desenvolupar nous tractaments d'aigua així com la seva reutilització. L'aplicació dels principis de l'economia circular al cicle de l'aigua ha posat de manifest la necessitat de percebre les aigües residuals com a font d'aigua i recursos. Així dones, la hibridació de tecnologies ja desenvolupades pot ajudar a complir els objectius de l'economia circular. A més, aquests sistemes híbrids són capaços de superar les limitacions deis tractaments convencionals. Així dones , en aquesta tesi, s'han desenvolupat i provat diferents sistemes híbrids (a escala de banc de proves i pilot) per al tractament d'aigües residuals urbanes i industrials. D'una banda, s'han operat tres configuracions de reactors UASB (Upflow Anaerobic Sludge Blanket) per comparar la posada en marxa, la hidrólisi dels sòlids i qualitat de l'efluent. Aquestes configuracions eren: biomassa flocular, biomassa flocular amb separació per membrana i biomassa granular amb separació per membrana (UASB-AnMBR). Els reptes d'aquest treball han estat tant la baixa temperatura com el baix contingut en DQO. La posada en marxa ha estat molt ràpida per als tres reactors, atribuïda a l'aclimatació prèvia dels fangs . Els resultats mostren que una configuració basada en UASB-AnMBR amb biomassa flocular ha estat adequada peral tractament d'aigües residuals urbanes amb baix contingut en DQO a 10°C. D'altra banda, s'ha investigat un AnMBR per al tractament de xerigot i la seva codigestió amb purí amb l'objectiu de recuperar aigua i energia . S'ha aconseguit una elevada eliminació de DQO (91% ± 7%) amb una producció de biogàs de 0,2 a 0,9 m3 de biogàs/kg de DQO eliminada. Per tant, es calcula que es podria obtenir una elevada recuperació d'energia amb un valor mitja de 2,4 kW/kg de DQO eliminada. Tot i que s'ha validat directament la recuperació d'energia, s'han detectat diverses limitacions en relació amb la reutilització de l'aigua. Aquestes limitacions inclouen una elevada concentració de sal en el permeat, que caldria eliminar abans de la seva reutilització. A més, s'ha optimitzat el pretractament pera aigües residuals petroquímiques amb l'objectiu de reciclar l'aigua. Aquest ha consistit en una coagulació-floculació (CF) seguida d'un MBBR (Moving Bed Biofilm Reactor) per tal de disminuir els sòlids en suspensió (SS) i el contingut orgànic. En aquest cas, només s'ha optimitzat la primera part del sistema híbrid ja que no s'han inclòs les etapes de membrana en aquest treball. Les proves de CF han mostrat una disminució de la terbolesa de les aigües residuals sense eliminació significativa de DQO. Aquest efluent s'ha tractat per MBBR. A I'MBBR s'ha mantingut una elevada eficiència d'eliminació de DQOs (80-90%). Els resultats obtinguts mostren que el MBBR és una tecnologia adequada per al pretractament de les aigües residuals petroquímiques. Finalment, s'ha estudiat una nova estratègia de tractament de lixiviats d'abocador per disminuir el seu impacte ambiental. El sistema s'ha basat en un pretractament amb bioreactor de membrana (MBR) pera l'eliminació de DQO, Ni SS seguit d'un tractament combinat d'osmosi inversa-electrodiàlisi reversible (01-EDR) pera l'eliminació de sals i disminució el volum de salmorra . L'MBR ha disminuït el carboni inorgànic en un 92 ± 8% i ha aconseguit una eliminació de N del 85%. Gracies a les etapes d'OI i EDR, la recuperació mitjana de tot el sistema ha superat el 90%. És important destacar que en aquest estudi s'han utilitzat membranes regenerades d'OI al final de la seva vida útil. Aquest fet, juntament amb el baix volum de salmorra {<10%) ha contribuït a disminuir !'impacte ambiental del tractament de lixiviats. Per tant, aquesta tesi s'ha dut a terme des d'un enfoc de recerca aplicada, amb l'objectiu de reduir la bretxa entre el desenvolupament tecnològic basic i la implementació industrial

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34

Hart, Vincent S. "An examination of biological phosphorus removal using bacterial counting and poly-β-hydroxybutyrate analysis in batch and continuous flow systems." Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/40652.

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The objective of this study was to examine excess biological phosphorus removing bacterial populations and their substrate utilization mechanisms. This study was a smaller part of a overall study of temperature effects upon excess biological phosphorus removal. Bacterial populations in both a continuous flow UCT (University of Cape Town) system and batch reactors were examined by direct counting using a well known staining procedure (Neisser staining), and a microscopic counting method developed by Cech and Hartman (1993). Substrate utilization was examined using PHB (Poly-β -Hydroxybutyrate - an internal substrate storage product) analysis by gas chromatography to supplement COD and acetate measurements. The results showed that Poly-P bacterial counts were significantly greater at a 5 day sludge age compared to a 10 day sludge age. It was noted from microscopic observations that the size of the poly-phosphate granules in the bacteria seemed to be a better indicator of system performance than the actual counts. It also was observed that the 'G' bacteria first described by Cech and Hartman (1993) were abundant at the 10 day sludge age but completely absent at the 5 day sludge age. PHB storage occurred in both the anaerobic zone and the first aerobic tank, and PHB utilization was seen in the subsequent aerobic tanks of the UCT system. The formation of PHB in the first aerobic reactor when no substrate was available supports the Mino (1987) model for excess biological phosphorus removal. In batch studies, substrate storage release were demonstrated in the aerobic zone. This explained why when acetate was present in the aerobic zone net phosphorus uptake didn't occur until all the acetate was utilized. When the temperature was lowered in the UCT system nitrification ceased. This resulted in soluble COD breakthrough into the aerobic zone, which stimulated filamentous growth, and eventually caused a lack of PHB formation. All of these factors contributed to a loss of excess biological phosphorus removal at the low temperature.
Master of Science

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35

Venckus, Julius. "Rekonstruotos Jurbarko nuotekų valyklos efektyvumas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100616_103144-42430.

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Magistriniame darbe nagrinėjama rekonstruotos Jurbarko nuotekų valyklos efektyvumas. Tyrimo tikslas – nustatyti nuotekų valyklos darbo efektyvumą po aeracinės sistemos rekonstrukcijos. Tyrimo objektas – Jurbarko nuotekų valyklos iškeliama aeracinė sistema, kuri buvo sumontuota 2008 m. Šiems tikslams pasiekti buvo išsikelti šie uždaviniai: teoriškai apibūdinti biologinio valymo įrenginius, įtakojančius biologinio valymo proceso efektyvumą ir įvertinti veikliojo dumblo sistemos pokyčius; nustatyti nuotekų išvalymo efektyvumą Jurbarko nuotekų valykloje; atlikti palyginamąją analizę vamzdinės ir diskinės aeracinės sistemos; nustatyti Jurbarko nuotekų valyklos elektros energijos sąnaudas. Nuotekų valyklos efektyvumas tirtas, pagal BDS7, bendrojo azoto (Nb), bendrojo fosforo (Pb) pasišalinimą iš vandens prieš aeracinės sistemos pakeitimą ir po aeracinės sistemos pakeitimo. Atlikus tyrimus nustatyta, kad nuotekų valykla po rekonstrukcijos dirba patikimai. Nuotekų liekamoji tarša neviršija DLK. BDS7 valytame vandenyje sumažėjo 16 %, bendrojo azoto (Nb) – 27 %, o bendrojo fosforo (Pb) – 56 %, lyginant su BDS7, Nb ir Pb prieš aeracinės sistemos pakeitimą. Cheminio reagento proceso veiksmui sunaudojama 488,8 kg/m, mažiau, o tuo pačiu sudaro 22295,2 Lt/m. mažiau išlaidų. Elektros energijos sąnaudos sumažėjo apie 14%.
The paper examined the reconstructed Jurbarkas domestic wastewater treatment plants performance. Purpose of the survey - the wastewater treatment plant efficiency of aeration system reconstruction. The object of research - Jurbarkas domestic wastewater treatment plants enters an aeration system that was installed in 2008. To achieve these goals has been to move the following tasks: a theoretical description of the biological treatment plant, which affect the biological treatment process and evaluate the effectiveness of the active sludge system changes, the efficiency of wastewater remediation Jurbarkas wastewater treatment facilities, to carry out a comparative analysis of linear and circular aeration system, the sewage treatment plant Jurbarkas electricity costs. Sewage treatment plant efficiency has been studied by BOC7 nitrogen (Nb), phosphorus (Pb) elimination of the water before aeration system replacement and the replacement of aeration systems. The investigation showed that sewage treatment facilities after renovation work reliably. Effluent residual contamination does not exceed the MRL. BOC7 treated water decreased by 16%, total nitrogen (Nb) - 27%, and total phosphorus (Pb) - 56%, compared with BOC7, Nb and Pb before aeration system replacement. Chemical reagent process steps used 488.8 kg/m and less, while at the same time is 22295.2 Lt/m. less cost. Electricity costs have fallen about 14 percent.

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Halvarsson, Björn. "Interaction Analysis in Multivariable Control Systems : Applications to Bioreactors for Nitrogen Removal." Doctoral thesis, Uppsala universitet, Avdelningen för systemteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-122294.

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Many control systems of practical importance are multivariable. In such systems, each manipulated variable (input signal) may affect several controlled variables (output signals) causing interaction between the input/output loops. For this reason, control of multivariable systems is typically much more difficult compared to the single-input single-output case. It is therefore of great importance to quantify the degree of interaction so that proper input/output pairings that minimize the impact of the interaction can be formed. For this, dedicated interaction measures can be used. The first part of this thesis treats interaction measures. The commonly used Relative Gain Array (RGA) is compared with the Gramian-based interaction measures the Hankel Interaction Index Array (HIIA) and the Participation Matrix (PM) which consider controllability and observability to quantify the impact each input signal has on each output signal. A similar measure based on the $\mathcal H_2$ norm is also investigated. Further, bounds on the uncertainty of the HIIA and the PM in case of uncertain models are derived. It is also shown how the link between the PM and the Nyquist diagram can be utilized to numerically calculate such bounds. Input/output pairing strategies based on linear quadratic Gaussian (LQG) control are also suggested. The key idea is to design single-input single-output LQG controllers for each input/output pair and thereafter form closed-loop multivariable systems for each control configuration of interest. The performances of these are compared in terms of output variance. In the second part of the thesis, the activated sludge process, commonly found in the biological wastewater treatment step for nitrogen removal, is considered. Multivariable interactions present in this type of bioreactor are analysed with the tools discussed in the first part of the thesis. Furthermore, cost-efficient operation of the activated sludge process is investigated.

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Martis, Prithy Caroline. "RENCA macrobeads inhibit tumor cell growth via EGFR activation and regulation of MEF2 isoform expression." Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1597229612949836.

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Larsen, Julie Melissa. "Measuring dinitrogen gas emissions from a lagoon treatment system." NCSU, 2004. http://www.lib.ncsu.edu/theses/available/etd-01052004-223912/.

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A method for collecting dinitrogen gas emissions from open pond waste treatment systems was developed. The method was critically tested in a laboratory for sources of air contamination to ensure reliable gas measurements. A laboratory experiment was done to estimate the rate at which dissolved dinitrogen would be stripped out of solution due to non-dinitrogen bubbles rising through the water column. A volumetric mass transfer coefficient for the process was estimated for clean water. The gas collection method was implemented in a partially aerated lagoon treatment system for dinitrogen and methane gas sampling. The volumetric mass transfer coefficient found in the laboratory for clean water was adjusted to compensate for field gas production rates, temperatures and wastewater quality to estimate the rate of stripped dinitrogen from the partially aerated lagoon. The estimated rate of stripped dinitrogen was subtracted from the total measured dinitrogen flux to estimate the dinitrogen produced biologically. Results from laboratory testing revealed that dinitrogen can be measured with low amounts of dinitrogen atmospheric contamination (0.57% N₂) and the preliminary field results suggest that biological denitrification did occur at this lagoon treatment system.

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Holtman, Gareth Alistair. "Design, installation, and assessment of a biological winery wastewater treatment system." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2573.

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Thesis (MTech (Civil Engineering))--Cape Peninsula University of Technology, 2017.
Currently in South Africa, most wastewater from small cellars is pH-adjusted and disposed of via land irrigation. This practice can lead to environmental degradation. There is a need for low cost, low maintenance solutions for the treatment of cellar effluent. Constructed wetlands provide such an option. However, the use of plants is problematic because winery effluent can be phytotoxic. After successful initial laboratory-scale experiments, an in-situ pilot scale biological sand filter (unplanted constructed wetland) system was designed, installed, and used to treat effluent from a small winery in the Western Cape, South Africa. The system is off-grid, totally self-regulating, and uses a modular approach which allows for the addition and subtraction of filter modules within the system to alter treatment capacity, retention time and/or rest filter modules. The system can be easily integrated into existing settling basins and/or retention ponds at small wineries. The biological sand filter was operational for 610 days, and showed promising results. The average chemical oxygen demand removal efficiency was 81% (range: 44-98%) with an average effluent of 324 mg/L, and an average flow rate of 413 L/day after the acclimation (start-up) period. The average hydraulic loading rate after the initial start-up period was 143 L/m3 sand day-1 (range: 67-222/m3 sand day-1), with an organic loading rate of 205 gCOD/m3 of sand day-1 (range: 83-338 gCOD/m3 sand day-1) which resulted in an organic removal rate of 164 gCOD/m3 of sand day-1. There was an average of 67% removal of total phenolics, thereby reducing the potential phytotoxicity of the effluent. In addition, there was a 1.6 times increase in calcium concentration, a 29% decrease in the average sodium adsorption ratio, and complete passive neutralisation of the acidic winery wastewater (final effluent pH range: 6.63 – 8.14. The findings of this study compare well with previous laboratory studies conducted with synthetic and authentic winery effluent. The system can potentially provide a low cost, energy efficient, low maintenance, sustainable means of treating cellar effluent at small wineries. Uptake of this technology may alleviate environmental degradation caused by irrigating land with inadequately treated effluent.

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MACOMBER, JEFF RAYMOND. "EFFECTS OF SOLIDS RETENTION TIME ON THE TREATMENT OF SYNTHETIC WASTEWATER USING A MEMBRANE BIOREACTOR." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin981401531.

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Md, Som Ayub. "Development of a process selection model for industrial wastewater treatment using an expert system." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244969.

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42

Bengtsson, Erica, and Sannam Hjertstrand. "Hybrid system for wastewater treatment in multifunctional wetlands - A case study at UNIVATES in Lajeado, RS, Brazil." Thesis, Halmstad University, School of Business and Engineering (SET), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-1604.

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Centro Universitaire UNIVATES is located in the town Lajeado that is situated in the most southerly state, Rio Grande Do Sul, in Brazil. The university has 5000 students, teachers and others staff. UNIVATES is not satisfied with their present wastewater situation and wants to improve it by eliminate the smell caused by the wastewater. They would also like to remove the oil that the storm water brings into the wetland. The high amount of particles in the storm water gives rise to a lot of sediments that eventually will fill up the wetland, and something has to be done about this, if the wetland should continue to be in use. Another aspect to consider is the wish of some people at UNIVATES, for the wetland to be a beautiful and recreational place. All these factors had to be considered, which led to the main question: How can the use of the wetland for wastewater treatment be combined with the request for the wetland to be a beautiful place with the wildlife preserved?

During the course Wetland Technology that we took before our departure to Brazil, we got introduced to the situation at UNIVATES by Professor André Jasper and Odorico Konrad who visited the course several times. They pointed out that the main issue is the smell from the wastewater and later during the field study at UNIVATES, more information were obtained through discussions, meetings and conversations with the people involved. Several visual inspections were carried out by walking around the wetland. We could determine where and how the inlets and outlets to the wetland were and when it was clear which inlets that brought wastewater and which that brought storm water, the water flow of the wastewater was estimated. Water samples from the wetland were collected at five different sites and analyses of pH, BOD, COD, N-Tot, phosphorus and metals were done by the accredited laboratory at UNIVATES. To test some of our theories, we did a smaller practical experiment that got the name Superficial Filtration Bed.

The results from the water samples showed the highest BOD, COD, N-Tot and Phosphorus levels in the samples from site 2 and 4 and this reveals that it is wastewater. This was also confirmed by the smell that we felt at these sites during the visual inspections. The results also showed that there is no wastewater coming from site 1, 3 and 5.

Our final proposal is to create a multifunctional wetland with the purpose to take care of both storm water and wastewater and at the same time work as a research and recreational area. The wetland, which would be divided into two parts, will constitute of all the fundamental functions; storm water buffering, sedimentation basin and biological oil separation and treatment. There will also be research sites and hybrid system for wastewater treatment. The hybrid system will consist of two steps where the first is aerobic and the second both aerobic and anaerobic. The first step is a Superficial Filtration Bed (SFB) and the second a FWS wetland.

The conclusion of this thesis is that more detailed research is needed to be able to dimension the specific functions correctly. With some further investigations the proposal presented is possible to carry through and our feeling when we left UNIVATES was that the people responsible really liked our ideas. They made it clear that they want to make a change and improve the situation and with the help they have gotten from us, they are a few steps closer to solving the problem.

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Bin-Fahad, Rashid Ahmed Mohammed. "Utilisation of anoxic/aerobic system for upgrading fixed-film biological wastewater treatment." Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248948.

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Morgan, Pamela B. "Study of population dynamics in a biological phosphorouos removal wastewater treatment system." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-08182009-040452/.

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Roshdieh, Rana. "Alternative Waste Treatment System for Poultry Processing Plants." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/46421.

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The objective of this research was to design an alternative wastewater treatment system for turkey processing plants to recover energy and reduce N and P to allowable discharge levels. The objective included: 1. Determine the quantity and quality of biogas produced from the turkey processing wastewater (TPW) and COD reduction efficiency. 2. Design a waste treatment system and validate proof of concept for simultaneous P and N removal with a goal of attaining effluent concentrations of 0.1 mg/L and 4 mg/L, for P and N, respectively. A lab-scale complete mixed anaerobic digester was used for turkey processing wastewater (TPW) digestion and biogas recovery running for 6 months. Along with the anaerobic digester, a two-sludge system called A2N-SBR consisting of an anaerobic-anoxic sequencing batch reactor and an attached growth post-nitrification reactor was added for biological nitrogen and phosphorus removal running for 3 months. Biogas production yields of 778 + 89 mL/gVSadded and 951.30 mL/g COD were obtained through anaerobic digestion. Also, an energy balance was conducted on a pilot scale digester for a turkey processing plant with wastewater production of 2160 m3/d and using a combined heat and power (CHP) enginefor conversion of biogas to heat and electricity. Although the biogas yield achieved in a complete mixed reactor was relatively lower than yields obtained in previous studies using reactors such as UASB, still a complete mixed reactor can be a good choice for biogas recovery from TPW and can be used for codigestion with some specific turkey processing byproducts for biogas recovery. Nitrogen and phosphorus removal in the A2N-SBR system were 47% and 75%, respectively, and during the study the nitrogen and phosphorus removal mean concentration in effluent did not meet the nutrient limits specified in the objectives. Average TP and TN in the effluent were 3.2 mg/L and 137 mg/L, respectively. Throughout the study, the nitrification reactor biofilm was not completely developed. Incomplete nitrification and poor settling might be the reasons that quality obtained in effluent was low. To improve the process condition in A2N-SBR, online monitoring of pH, dissolved oxygen (DO) and oxidation reduction potential (ORP) can help to optimize each stage in the SBR and stages duration can be set based on the results.
Master of Science

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Soleimani, Karizmeh Mohsen. "Investigation of Biologically-produced Solids in Moving Bed Bioreactor (MBBR) Treatment Systems." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23494.

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Lower production rate of solids in attached growth moving bed bioreactor (MBBR) systems as compared to conventional activated sludge (AS) systems makes them an attractive choice for municipal wastewater treatment (Ødergaard et al. 1994). However, the production of biologically-produced solids in MBBR systems is currently not well defined and requires additional investigation. Three identical MBBR reactors were operated under the same dissolved oxygen (DO) concentration, influent pH and volume of Anoxkalnes media in two different experimental phases. In the first phase, the hydraulic retention time (HRT) kept constant in three reactors and SALR increased and in the second phase, the SALR was the constant parameter while HRT increased. These two phases were implemented to investigate the effect of variations in HRT and SALR on biologically-produced solids in MBBR reactors. This study demonstrated that HRT and SALR play an important role in settling characteristics of the biologically-produced solids in MBBR systems.

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Brannan, Kenneth P. "Substrate stabilization in the anaerobic stage of a biological phosphorus removal system." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/49992.

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48

Moore, Rebecca L. L. "Investigating the use of oligonucleotides for the treatment of muscular dystrophy." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/34150/.

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Antisense oligonucleotide therapy is one of the most promising strategies for treatment of myotonic dystrophy type 1 (DM1), type 2 (DM2) and Duchene muscular dystrophy (DMD). These three diseases have nuclear retained mRNA, suitable for antisense therapy targeting. The delivery of oligonucleotides to their desired target has long been an obstacle in antisense therapy with a large number of delivery reagents or methods having adverse side effects. Promising work published detailing the successful delivery of various chemically modified oligonucleotides (CMOs) naked, via gymnosis, led to us investigating a number of these CMOs: deoxyribonucleic acids (DNA), Peptide nucleic acids (PNAs), 2’OMethyl (2’OMe), and Phosphorodiamidate morpholino (PMO) oligonucleotides. In DM1 expanded CUG repeat (CUGexp) mRNAs aggregate in the nucleus forming “foci”. Testing the CMOs effectiveness at disrupting nuclear foci in a cell based assay, using high content imaging to visualise the number, size and intensity of foci we initially discovered that PNA and 2’OMe, were seemingly taken up via gymnosis by DM1 cells, and removed nuclear foci at nanomolar concentrations. However further experimentation using live cell imaging indicated that although all CMOs could enter the cell, in all disease models tested, via gymnosis, the CMOs could not penetrate the nuclear membrane. In depth analysis led us to identify an artefact of the in-situ process used to identify these foci, explaining earlier positive results. As the target mRNA is trapped within the nuclear compartment we investigated several transfection reagents for their ability to deliver 2’OMe oligonucleotides to the nucleus using live cell fluorescent imaging and a modified northern blot based method. It was established that polyethylenimine could successfully deliver 2’OMe oligonucleotides to the cell, with a high abundance of the oligonucleotide residing within the nuclear compartment. It was observed that PEI degrades the expanded nuclear retained repeat in the DMPK transcript of a DM1 patient cell line alone, without the addition of an antisense agent, in a concentration dependent manner.

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Grassi, Michelle Elenore. "Development of a diffusion based ethanol delivery system to promote reducing environments for the bioremediation of contaminated groundwater." University of Western Australia. School of Biomedical and Chemical Sciences, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0066.

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[Truncated abstract] An ethanol delivery system, consisting of silicone (poly(dimethylsiloxane)) tubing coiled and shaped as mats, was characterised and evaluated for its potential to act as a permeable reactive barrier (PRB), to promote reducing conditions and enable the enhanced bioremediation of a variety of groundwater contaminants in situ. Aqueous ethanol solutions were recirculated through the inner volume of the silicone polymer tubing in the mat, to allow permeation and delivery of ethanol by diffusion through the tubing walls to a target contamination zone. The aim of the system was to provide control over subsurface geochemistry by overcoming carbon source limitations, and as a result stimulate indigenous bacteria to remove contaminants. The physical properties of the silicone tubing were initially characterised, which included the determination of the ethanol sorption and diffusion properties of the tubing. A model for the mass of ethanol transferred via diffusion from an aqueous solution on the inner volume of a length of polymer tubing was developed to enable prediction of the ethanol delivery capacity of the silicone polymer mats. A number of large-scale laboratory column studies were then conducted to validate this ethanol mass delivery model, and to evaluate the use of silicone polymer mats to deliver ethanol and promote the biodegradation of a range of different contaminated groundwaters. The laboratory column experiments were observed to produce ethanol mass flux delivery statistically similar to that predicted by the model; however this was only with the application of an effective diffusion coefficient within the model, which was determined from the model under subsurface-simulated conditions. Ethanol delivery using the silicone tubing polymer mat system was also quantified in a pilot field-scale demonstration. The mass of ethanol delivery in the field was shown to be within the range of model-predicted ethanol delivery; however delivery was not as consistent and predictable as that observed in the column studies. Successful ethanol enhanced nitrate contamination removal (via denitrification) was observed at a field scale. For field applications, this innovative polymer mat amendment delivery system may provide targeted, predictable and cost-effective amendment delivery compared to aqueous injection methods for groundwater bioremediation, however, knowledge and quantification of the hydrogeology of the particular field site is required. Two other ethanol-driven biologically-mediated contaminant removal processes were also investigated in the laboratory-scale soil column studies, and included the assessment of the removal of dissolved metals/sulfate via sulfate reduction and metalsulfide precipitation, and the removal of trichloroethene via reductive dechlorination.

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Merilles, Kimberly Michelle LaMar. "Effect of Bio-Augmentation Product BiOWiSH® Septic Rescue on the Wastewater Treatment Performance of Residential Septic Tanks." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2003.

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Residential septic systems provide reliable wastewater treatment for over 26 million homes and facilities in the United States, and many more worldwide. When properly maintained, these systems are reliable, low-cost, and long-term treatments for residential wastewater. When neglected, septic systems can fail and lead to health concerns and ecological harm to soil and groundwater contamination through the improperly treated wastewater effluent. This study tested the effect of the bio-augmentation product BiOWiSH® Septic Rescue of BiOWiSH® Technologies International, Inc. (hereafter referred to as BiOWiSH) on the biological treatment of residential septic tanks. BiOWiSH is meant to act as a bio-augmentation product through the addition of a proprietary blend of Bacillus and Lactic Acid producing bacteria. These microbes act as a biocatalyst to enhance and encourage a range of hydrolytic, oxidative, and reductive biochemical reaction and promote digestion of bio solids and ammonification within the septic tanks. To test the effect of BiOWiSH on the treatment of residential septic tanks, four 32-gallon tanks were constructed and filled with water and primary sludge from the primary clarifier at the San Luis Obispo Water Resource Recovery Facility. Two tanks were dosed with the recommended amount of BiOWiSH; one tank had no additive biological treatment and served as the control; one tank was dosed with RID-X® Septic Maintenance, a leading competitive product (hereafter referred to as RID-X). Each tank functioned as a plug-flow reactor. Primary sludge and tap water was added daily and effluent was sampled on a daily or weekly basis, based on the parameters being tested. Effluent water samples were tested for removal of ammonia, nitrates, total suspended solids, and biological oxygen demand. Temperature and pH were also recorded. v These analyses indicated no significant advantage from the addition of BiOWiSH in the reduction of ammonia, total suspended solids, or biological oxygen demand over the control tank or the tank dosed with the RID-X competitive product. Nitrates (in the form of nitrate and nitrite) did not form in any of the tanks. Future studies are needed to validate these results. Additional studies should include an analysis of experimental time frames, sampling frequency, and testing additional products designed to rescue failed or failing septic systems. BiOWiSH should also be tested further in its potential ability to enhance the biological treatment of septic tank effluent once the wastewater has entered aerobic leach fields.

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Dissertations / Theses on the topic 'Biological treatment systems'

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