Dissertations / Theses on the topic 'Removal'
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Gong, Han. "Interactive shadow removal." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.665432.
Full textGomez, Ryan. "Orbital Debris Removal." Digital Commons at Loyola Marymount University and Loyola Law School, 2017. https://digitalcommons.lmu.edu/etd/395.
Full textWong, Hiu Man. "Removal of pathogens by membrane bioreactor : removal efficiency, mechanisms and influencing factors /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202004%20WONGH.
Full textIncludes bibliographical references (leaves 93-102). Also available in electronic version. Access restricted to campus users.
Henderson, Rita Kay. "PosiDAF for algae removal." Thesis, Cranfield University, 2007. http://dspace.lib.cranfield.ac.uk/handle/1826/4472.
Full textTripathi, Sachchida Nand. "Removal of charged aerosols." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325074.
Full textDong, Chun. "Binder removal in ceramics." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/14101.
Full textMori, Brett Cote John Rowland Kyle Wells Micah. "Chip removal tool project /." Click here to view, 2009. http://digitalcommons.calpoly.edu/mesp/9.
Full textProject advisor: James Meagher. Title from PDF title page; viewed on Jan. 20, 2010. Includes bibliographical references. Also available on microfiche.
Gustafsson, Olof. "Nanoparticle Removal and Brownian Diffusion by Virus Removal Filters: Theoretical and Experimental Study." Thesis, Uppsala universitet, Nanoteknologi och funktionella material, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-335802.
Full textPopple, Tina. "The behaviour, fate and removal of pharmaceuticals in biological nutrient removal sewage treatment." Thesis, University of Portsmouth, 2013. https://researchportal.port.ac.uk/portal/en/theses/the-behaviour-fate-and-removal-of-pharmaceuticals-in-biological-nutrient-removal-sewage-treatment(7b67f73d-d777-4a25-9b7b-0ae3edcc58dc).html.
Full textWallace, Laura. "Condit dam removal : a decision-making comparison with removal of Elwha River dams." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/17659.
Full textDepartment of Geography
Lisa M.B. Harrington
While environmental concerns have played a secondary role in dam removal rationales thus far, the Condit and Elwha removal projects could signal a change in governmental and public priorities in dam management in the United States (Born et al. 1998; Bednarek 2002). For this research, I compared two dam removal projects designed to restore native salmon runs in two rivers in Washington State: the Condit Dam on the White Salmon River and the Elwha and Glines Canyon Dams on the Elwha River. This thesis asks: given choices of preserving dams that produce clean electricity and the well-established lake-based habitats created by their reservoirs or re-establishing a free-flowing river to reestablish fish and wildlife populations, how are decisions made, and what does the process and outcome mean to local communities? Research interview data was used in combination with policy documents to answer three research questions: 1) What factors affect decision-makers’ and other stakeholders’ support for (or rejection of) dam removal? 2) How did stakeholders’ perceptions and opinions play a role in the decision-making process? and 3) What can we learn from problems and successes evident from the dam removal decision processes? The main factors influencing both the Condit Project and the Elwha Project were environmental (salmon restoration), political (meeting legislative requirements for fish passage), and economic (finding the least cost fish passage alternative). The primary motivation for both projects was salmon restoration via the provision of federally mandated fish passage. The possibility of regaining a valuable resource spurred Tribal, federal, and state agencies to advocate for the removal alternative. Dam owners in both cases desired the least cost option, resulting either in their consent to removal (Condit Project) or selling the dams and relinquishing responsibility to the federal government (Elwha Project). Both took over two decades to complete and were removed in 2011. Perceptions of the relative importance of removal/retention options and dissatisfaction with the decision-making process led to polarization of the communities affected by the dam removals and contributed to the 20+ year project timelines. In order to promote good will and understanding between decision makers and stakeholders, two lessons can be learned from the Condit and Elwha Projects: 1) actively seek to include both proponents and opponents in decision-making and 2) establish robust communication among stakeholders and decision makers. Additionally, preliminary evidence indicates that dam removal does result in movement of salmonids to river reaches that had been blocked by dams, and dam removal may also lead to unintended consequences related to local environmental quality and resource access, such as short term air quality concerns and longer term effects on groundwater availability.
Eriksson, Rosenkvist Kajsa. "Laser Orbital Derbis Removal : Studies of Spacecraft Debris Removal Using Ground Based Lasers." Thesis, Luleå tekniska universitet, Rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-77103.
Full textPrintz, Kathryn Elizabeth. "The Investigation of Nitrite Accumulation and Biological Phosphorus Removal in an Intermittently Aerated Process Combining Shortcut Nitrogen Removal and Sidestream Biological Phosphorus Removal." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/95853.
Full textMaster of Science
It is important to reduce nitrogen and phosphorus concentrations in wastewater treatment effluent in order to both protect the environment from eutrophication and to meet the increasingly stringent nutrient effluent discharge limits imposed by the EPA. Conventional biological nitrogen removal is achieved through nitrification and denitrification converting ammonia to nitrogen gas, where nitrogen gas is volatile and leaves the system naturally. Phosphorus removal can be achieved through either chemical addition or through biological phosphorus removal, where phosphorus is taken up in cells and removed from the system by the subsequent solids wasting of these cells. The combination of biological nitrogen and phosphorus removal can be improved to increase energy efficiency, reduce costs including aeration and chemical addition costs, increase system capacity and reduce tank sizes, and reduce biomass production, all while achieving low effluent N and P concentrations. Short-cut nitrogen removal can increase the efficiency of biological nitrogen removal. Deammonification, the combination of partial nitritation and anammox, has the potential to reduce wastewater treatment plant (WWTP) aeration costs by 63%, carbon requirements by 100%, and biomass production by 80% (Nifong, Nelson, Johnson, and B. Bott, 2013). Deammonification is the combination of partial nitritation and anammox. Anaerobic ammonia oxidation (anammox) is a useful class of bacteria that converts ammonia and nitrite straight to nitrogen gas in anaerobic conditions, which is a more direct pathway than the conventional nitrification-denitrification pathway. Anammox requires a nitrite supply, which can supplied by partial nitratation of ammonia to nitrite, performed by ammonia oxidizing bacteria (AOB) aerobically in the deammonification process. In order for partial nitratation to work, there needs to be nitrite oxidizing bacteria (NOB) out-selection so that the nitrite produced by AOB does not get oxidized to nitrate. Enhanced biological phosphorus removal (EBPR) is accomplished by the taking up and storing of orthophosphate (OP) by phosphorus accumulating organisms (PAOs). These organisms require an anaerobic carbon-storage phase followed by an aerobic growth phase where the internally stored carbon is used for growth. During the cell growth phase of PAOs in aerobic conditions, PAOs are able to take up more OP than they previously released in anaerobic conditions, creating a net OP removal from the system. There has been recent success in recycle activated sludge (McIlroy et al.) fermentation to enhance biological phosphorus removal, which works to promote hydrolysis, fermentation, and EBPR enhancement (Houweling, Dold, and Barnard, 2010). A portion of the RAS is introduced to an anaerobic zone before returning to the main process, allowing for extra VFA production and adsorption by PAOs. RAS fermentation solves the issue of carbon needed for EBPR in VFA/carbon limited systems without having to add too much additional carbon, creating a carbon efficient EBPR system. The research outlined in this study was done at the Hampton Road Sanitation District's (HRSD) pilot plant located within HRSD's Chesapeake-Elizabeth WWTP in Virginia Beach VA. The pilot is run in an A/B process that works in two separate steps: the A-stage is the first step that works to remove carbon by oxidation, and by adsorption so it can potentially be diverted, and the B-stage is the second step where biological nitrogen removal (BNR) is done. The BNR phase consists of an anaerobic selector followed by four completely stirred tank reactors (CSTRs) that are intermittently aerated to provide aerobic and anoxic phases. The pilot also has an anammox polishing step following B-stage. The nitrogen removal goal for this research was short-cut nitrogen removal via deammonification, by producing partial nitritation in B-stage and polishing with anammox. A B-stage RAS fermenter, along with an A-stage waste activated sludge (WAS) fermenter that feeds VFA into the RAS fermenter, was implemented to the existing pilot to enhance biological phosphorus removal. The overall goal of this study was to successfully combine short-cut nitrogen removal with sidestream EBPR to achieve low effluent N and P concentrations in the most energy and carbon efficient way possible. EBPR was achieved about eight months after the implementation of the RAS and WAS fermenter to the pilot. A period of B-stage effluent OP that was consistently below 1 mg/L OP was observed right before an unexpected period of high nitrite in the B-stage effluent. The high effluent nitrite lasted for 106 days and ranged from 1.1-5.9 mg/L of effluent nitrite during this time. The nitrite accumulation was unexpected because weekly maximum activity tests for AOB and NOB showed that NOB out-selection was not occurring. The first phase of this research investigates the cause of the nitrite accumulation. Based on profiles taken in the reactors in the aerobic and anoxic phases, and based on denitrification activity tests, it was determined that the nitrite accumulation was due to partial denitrification of nitrate to nitrite. Because this partial denitrification was happening in the reactor anoxic times where external should have been used up, it was determined that the source of the partial denitrification was from a bacteria using internally stored carbon during anoxic periods as the electron supply for partial denitrification. Research has showed that EBPR systems promote bacteria that are capable of storing carbon internally and keeping that carbon stored through an aerobic phase and then using that stored carbon for denitrification following an aerobic phase (Vocks et al., 2005), like observed in this research. The second phase of this research sought to link the nitrite accumulation and bio-P activity to the VFA added to the RAS fermenter. The VFA addition was decreased in phases, and with that a decrease in nitrite in the effluent was observed. The bio-P activity became more unstable after the nitrite accumulation occurred, but all bio-P activity ceased after VFA addition to the RAS fermenter ceased. It was concluded, unsurprisingly, that the VFA added to the RAS fermenter was the source of the internally stored carbon that caused the nitrite accumulation, and necessary for bio-P enhancement. The third phase of this research sought to recreate the low effluent OP period and the nitrite accumulation by controlling the VFA dose to the RAS fermenter. The average soluble chemical oxygen demand (sCOD) per OP (fermenter sCOD g/day / total OP-fermenter + influent- g/day) of the period of low effluent OP was calculated, and the dose from the WAS fermenter was controlled to meet 60% of the calculated value. The calculated dose was 13.6 gC/gP, but the actual average dose from controlling the load during this period was 15.6 ± 3.0 gC/gP. The average VFA/OP (g VFA as acetate/ g total OP) dose for the first low effluent OP period was 9.4 ± 3.6 g/g, and the average dose for the third phase of research was 5.5 ± 1.3 g/g. No nitrite accumulation occurred in this phase, but another consistent low effluent OP period did occur. From linear correlation analysis, the highest r2 values relating the low effluent OP periods and the COD loads to the RAS fermenter for both periods were between VFA g/day vs OP mg/L, at r2=0.18 for the first period and r2=0.65 for the second. This shows that effluent OP < 1 mg/L can be achieve at 5.5 or 9.4 (g VFA as acetate/ g total OP). Since no nitrite was observed in phase 3, than the probable VFA load needed to provide enough internal storage to produce nitrite accumulation by partial denitrification is probably between 5.5-9.4 (g VFA as acetate/ g total OP). This research was significant because the link between nitrite accumulation and bio-P enhancement with sidestream RAS and WAS fermentation was confirmed. Partial denitrification of nitrate to nitrite could be used as an alternative source of nitrite for anammox, instead of NOB out-selection and partial nitritation of ammonia to nitrite by AOB, in combined EBPR and short-cut nitrogen removal systems. If sidestream EBPR systems could be used to promote nitrite accumulation and bio-P activity to produce low effluent OP and nitrogen removal efficiently than short-cut nitrogen removal and EBPR could be successfully combined in an efficient way. Future work needs to be done on the organism that is capable of nitrite accumulation and if that organism can be enhanced in conjunction with EBPR organisms to promote both nitrite accumulation and low effluent OP simultaneously.
Eveborn, David. "Bed filters for phosphorus removal in on-site wastewater treatment : Removal mechanisms and sustainability." Licentiate thesis, KTH, Land and Water Resources Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12048.
Full textFor many surface waters, phosphorus (P) leaching is a serious problem that should be minimized to prevent eutrophication. In Sweden there is a demand for physical and technical development of high-performance P removal techniques to reduce phosphorus leaching from on-site wastewater treatment systems to the Baltic Sea. However, although these systems are designed to reduce eutrophication there are also other environmental impacts to be considered when implementing them in on-site systems; energy use and global warming potential are two examples. This study has investigated several bed filter materials (reactive media and natural soils) for their total environmental impact (in commercial applications) as well as for the predominating chemical phosphorus removal mechanisms. The use of life cycle assessment revealed that several reactive bed filters are relatively energy-consuming due to the material manufacturing process. Characterization of phosphorus compounds in used reactive media provided evidence for calcium phosphate precipitation as the predominating P removal mechanism in alkaline filter materials. However, in soil treatment systems with noncalcareous soils, batch experiments and extractions suggested that aluminium compounds were important for P removal. According to mass balance calculations that compared accumulated P with the estimated P load in a soil treatment system, the long term P removal capacity was very low; only 6.4 % of the applied phosphorus had been removed during 16 years of operation.
Ahlin, Björn T. I. "Nitrogen Removal in a Vacuum Tank Degasser : An Investigation on the Nitrogen Removal Performance." Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-256066.
Full textFörändringar till följd av HYBRIT projektet kommer påverka SSAB Oxelösunds stålverk. Masugn och LD konverter skall ersättas med ljusbågsugns teknologi. Ett problem till följd av detta är kvävehalter i stålet. Enligt litteraturen är kvävehalterna betydligt högre i stål tappat från en ljusbågsugn. Med kvävehalter runt 60-70 ppm jämfört med stål tappat från en LD konverter som har kvävehalter kring 25 ppm. Därför krävdes en undersökning kring kvävereningpotentialen för SSAB Oxelösunds vakuum tank avgasare. Industriella experiment med minskad slaggmängd jämfört med standard praxis blev utförda. Detta utfördes med tanken att minskad slaggmängd skulle ge en större effektiv reaktionsarea. Intentionen var att utföra försök först med halverad slaggmängd följt av slaggfria försök. Dock, på grund av produktions praktiska problem vid verket blev försöken avbrutna. Som en följd av detta blev bara försök med halverad slaggmängd utförda och jämförda med processdata från standard praxis. Kvävereningsberäkningar på historisk processdata utfördes. En parameter som representerade genomsnittlig reaktionshastighet, vilken beror på den effektiva reaktionsarea blev erhållen, validerad och senare applicerad på ett hypotetiskt framtida scenario. Resultaten indikerar att minskad slaggmängd har en positiv inverkan på den effektiva reaktions arean och till följd av detta även en positiv inverkan på kväverening. Dock är för få försök utförda för att kunna fastställa detta. De slutsatser som dras är att vakuum anläggningen vid SSAB Oxelösund har möjligheten att, med förlängd vakuumbehandlingstid, rena de ökade kvävehalter till nivåer runt 20-30 ppm. Ytterligare slutsatser var att ytaktiva element, såsom syre och svavel, i stålet har en stor negativ påverkan för kväverening. Samt att den effektiva reaktionsarean är av stor betydelse för kväverening. Därför bör ansträngningar tas för att minska koncentrationen av ytaktiva element samt att försöka göra den effektiva reaktionsarean så stor som möjligt. Slutligen fastställdes det att ytterligare studier är nödvändiga för att öka kunskapen kring förebyggande tekniker och reningstekniker för kväveföroreningar i stål.
Lejon, Anna G. C. "Ecosystem response to dam removal." Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-55586.
Full textSch??fer, Andrea Iris Chemical Engineering & Industrial Chemistry UNSW. "Natural Organics Removal using Membranes." Awarded by:University of New South Wales. Chemical Engineering and Industrial Chemistry, 1999. http://handle.unsw.edu.au/1959.4/20695.
Full textGeoffroy, Nicolas. "Selenium removal from aqueous solutions." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104555.
Full textLa chimie aqueuse des réactions de réduction entre les ions sélénieux et le dithionite de sodium, le sulfure de sodium et les ions stanneux ont été étudiées. Les précipités résultant de cette réaction ont été caractérisés par différentes techniques comme la microscopie électronique à balayage, la diffraction à rayons X et la spectrométrie de photoélectrons induits par rayons X. Dans le cas du dithionite de sodium, ce projet a démontré que, pour un pH initial inférieur à 1.7 et un ratio stœchiométrique de dithionite supérieur à trois, moins de 0.5 ug/L de sélénium(IV) restait en solution moins d'une minute après l'addition du réactif. Par contre, le précipité, formé en majorité de sélénium rouge amorphe, n'était pas stable en présence des composés issus de la réaction de décomposition du dithionite et était partiellement re-dissous après quelques heures. Dans le cas de la réaction entre l'acide sélénieux et le sulfure de sodium, les résultats indiquaient que pour un ratio molaire sulfur/sélénium plus grand que 1.8 et un pH sous 7.0 la réaction de précipitation était complète et moins de 5 ug/L de sélénium (IV) restait en solution. Aucune précipitation n'a été constatée pour un pH plus élevé que 9.5 et la réaction était incomplète pour un pH entre 7 et 9.5. Le précipité semblait être composé d'une solution solide Se-S formé de molécules circulaires répondant à la formule SenS8−n. Par contre, pour un pH plus élevé que 7, la précipitation du sélénium était incomplète à cause de la formation d'un précipité de sélénium colloïdal. De plus, dans le cas des solutions industrielles, de hautes concentrations de dioxyde de souffre dissous (> 5g/L) diminuait l'efficacité de la réaction de précipitation.En ce qui concerne la réaction entre le sélénium(IV) et l'étain, pour un pH initial sous 1.3 et un ratio molaire étain/sélénium plus grand que deux, moins de 5 ug/L de sélénium restait en solution après la réaction. Les analyses ont révélé que le précipité était composé de parts approximativement égales de séléniure d'étain et de dioxyde d'étain et que ce dernier pouvait adsorber une petite quantité d'ions sélénieux. Finalement, ce projet a démontré que le sélénium(IV) peut être réduit, à la température ambiante, par une solution ultra-acide riche en sulfites. Une fois le sélénium précipité sous forme colloïdale, la concentration originale de celui-ci peut ensuite être déterminée par turbidimétrie. Par ailleurs, cette méthode est aussi efficace sur des solutions industrielles contenant du sélénium(IV) et peut donc être appliquée pour l'analyse en temps réel de cet élément.
Eke, Paul Emeka. "Hydrocarbon removal with constructed wetlands." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/3155.
Full textSouthgate, Jonathan. "Wax removal using pipeline pigs." Thesis, Durham University, 2004. http://etheses.dur.ac.uk/2995/.
Full textPaschalis, Stefanos. "Relativistic One-Nucleon Removal Reactions." Thesis, University of Liverpool, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502216.
Full textNicolau, Nicoletta. "Automatic artefact removal from electroencephalograms." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430848.
Full textCho, Taeg Sang. "Motion blur removal from photographs." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62385.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (p. 135-143).
One of the long-standing challenges in photography is motion blur. Blur artifacts are generated from relative motion between a camera and a scene during exposure. While blur can be reduced by using a shorter exposure, this comes at an unavoidable trade-off with increased noise. Therefore, it is desirable to remove blur computationally. To remove blur, we need to (i) estimate how the image is blurred (i.e. the blur kernel or the point-spread function) and (ii) restore a natural looking image through deconvolution. Blur kernel estimation is challenging because the algorithm needs to distinguish the correct imageblur pair from incorrect ones that can also adequately explain the blurred image. Deconvolution is also difficult because the algorithm needs to restore high frequency image contents attenuated by blur. In this dissertation, we address a few aspects of these challenges. We introduce an insight that a blur kernel can be estimated by analyzing edges in a blurred photograph. Edge profiles in a blurred image encode projections of the blur kernel, from which we can recover the blur using the inverse Radon transform. This method is computationally attractive and is well suited to images with many edges. Blurred edge profiles can also serve as additional cues for existing kernel estimation algorithms. We introduce a method to integrate this information into a maximum-a-posteriori kernel estimation framework, and show its benefits. Deconvolution algorithms restore information attenuated by blur using an image prior that exploits a heavy-tailed gradient profile of natural images. We show, however, that such a sparse prior does not accurately model textures, thereby degrading texture renditions in restored images. To address this issue, we introduce a content-aware image prior that adapts its characteristics to local textures. The adapted image prior improves the quality of textures in restored 6 images. Sometimes even the content-aware image prior may be insufficient for restoring rich textures. This issue can be addressed by matching the restored image's gradient distribution to its original image's gradient distribution, which is estimated directly from the blurred image. This new image deconvolution technique called iterative distribution reweighting (IDR) improves the visual realism of reconstructed images. Subject motion can also cause blur. Removing subject motion blur is especially challenging because the blur is often spatially variant. In this dissertation, we address a restricted class of subject motion blur: the subject moves at a constant velocity locally. We design a new computational camera that improves the local motion estimation and, at the same time, reduces the image information loss due to blur.
by Taeg Sang Cho.
Ph.D.
Bernstein, Howard. "A system for heparin removal." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15291.
Full textMICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.
Bibliography: leaves 255-264.
by Howard Bernstein.
Ph.D.
Venkatraman, Amruth. "Exploring constraint removal motion planners." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106389.
Full textThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (page 47).
We present algorithms for motion planning that can tolerate collisions. Because finding a path of minimum cover is prohibitively expensive, we investigate algorithms that work well in practice and find solutions close to the true minimum cover solution. We introduce the notion of removal importance for obstacles and the family of iterative obstacle removing RRTs (IOR-RRTs). This family of algorithms operate similarly to the RRT but iteratively tolerate more collisions in trying to identify a path. One member of the family that performs well is the search informed IOR-RRT. This search technique first performs bidirectional collision-free search to find a clear path if possible. In failure, it iteratively selects an obstacle for removal using its removal importance. We measure the performance of our algorithms on a multi-link robot operating in both environments with feasible paths and those where collisions must be allowed.
by Amruth Venkatraman.
M. Eng.
Greben, Harma. "The biological sulphate removal process." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52490.
Full textENGLISH ABSTRACT: South Africa is one of the world's major coal producers, resulting in the second highest foreign exchange earner for South Africa. However, the mining industry contributes negatively to (ground) water pollution, due to the formation of acid mine drainage (AMD). AMD originates from the bacterial oxidation (Thiobacillus ferrooxidans) of pyrite (FeS) and contains high levels of sulphate and metals. Sulphate rich waters can be treated applying the biological sulphate removal technology. This study concentrated on biologically removing sulphate from synthetic feed- and mine water, using the single-stage completely-mixed reactor system. The advantage of using this reactor system is that except for removing sulphate from about 2000 to less than 200 mg/t', it can also partly biologically remove the formed sulphides. It was established that both ethanol and sugar can be used, as the carbon and energy source, however ethanol is more cost effective than sugar. Ethanol dosage and Hydraulic Retention Time (HRT) studies were undertaken to investigate at what concentration, the highest sulphate and sulphide removal rates were achieved. It was found that the highest sulphate reduction rates were obtained when using 1mf ethanol/f feed and that the removal rates were dependent on the HRT: the lower the HRT, the higher the sulphate reduction rate. The highest sulphide oxidation rate was achieved at the HRT of 6 h. It was, furthermore shown that the single stage completely-mixed reactor system could successfully be used to remove sulphate from Schoongezicht mine effluent, not only removing the sulphate, but also most of the metals, thereby increasing the mine effluent pH from 2.5 to 7. The conclusion of this study was that a completely-mixed reactor system, as described in this thesis, can successfully be applied to treating acid mine drainage using ethanol (1 m.e etanol/f feed water) as the carbon and energy source at a hydraulic retention time as low as 4 hours. This technology has great potential for pilot- and full-scale treatment of sulphate rich effluents such as acid mine drainage.
AFRIKAANSE OPSOMMING: Suid Afrika is een van die vemaamste steenkool produseerders in die wereld, terwyl die uitvoer van steenkool die land se tweede hoogste verdiener is van buitelandse valuta. Ongelukkig dra hierdie industrie ook by tot die besoedeling van (grond) water, veral vanwee die vorrning van suur myn afloop. Bakteriese oksidasie (deur Thiobacillus ferrooxidansy van piried (FeS) is hoofsaaklik verandwoordelik vir die vorrning van suur myn afloop bevattende hoe konsentrasies van sulfaat en metale. . Die toepassing van biologiese sulfaatverwyderingsprosesse vir die behandeling van sulfaatryke waters is vroeer gedemonstreer. Die doel van hierdie studie was om 'n enkel-stadium reaktor met volledige vermenging te evalueer en te optimiseer om toegepas te word vir die biologiese verwydering van sulfaat vanuit sinteties bereide, sowel as mynwater. Hierdie reaktor is in staat om sulfaat te verwyder vanaf vlakke van ~ 2000 tot minder as 200 mg/P. 'n Verdere voordeel gepaard met die gebruik van hierdie reaktor is dat die sulfied wat gevorm word tydens sulfaatreduksie, gedeeltelik verwyder word deur die oksidasie daarvan na So. Die resultate wat behaal is in hierdie studie het aangedui dat beide etanol en suiker gebruik kan word as die koolstof en energiebron, terwyl etanol meer koste-effektief aangewend kon word. In teenstelling was metanol nie 'n geskikte koolstofbron vir sulfaatverwydering nie. Eksperimente is daarvolgens uitgevoer om toestande van optimum etanoldosering en hidroliese retensietyd (HRT) vir maksimum sulfaat- en sulfiedverwydering te bepaaJ. Die hoogste reduksie tempo's was verkry met 'n toediening van 1 mP etanol/f invloei, en die effektiwiteit van verwydering was afhanklik van HRT. Hoe laer die HRT, hoe hoer die tempo van sulfaatverwydering. Die beste sulfaatverwyderingstempo was behaal teen 'n HRT van 6 uur. Die resultate het verder aangetoon dat die enkel-stadium reaktor met volledige vermenging in staat was om sulfaat effektief te verwyder, en die pH te verhoog vanaf na 2.5 tot 7, in mynuitvloeisels van 'n plaaslike steenkoolmyn. Die gevolgtrekking uit hierdie werk is dat 'n volledig-gemengde reaktorstelsel, soos beskryf in die huidige studie, geskik is vir die suksesvolle behandeling van suur mynafloopwater met die gebruik van etanol (l mflP toevoerwater) as koolstof- en energiebron by 'n hidrouliese retensietyd tot so laag as 4 uur. Die tegnologie het groot toepassingspotensiaal vir volskaalse behandeling van sulfaatryke afloopwaters soos by. suur mynafloop.
Liss, Jago Milan. "Ecology of biological sulfate removal." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53400.
Full textENGLISH ABSTRACT: A laboratory-scale model was used to simulate biological sulfate removal. The focus of the research was microbial community response, such as the relative abundance of functional groups to changes in influent medium composition. Specific oligonucleotide probes were obtained that recognised sulfate reducing bacteria (SRB) within the biofilm community. Terminal restriction fragment length polymorphism (T-RFLP) and BIOLOG™ Ecoplate analyses were used to study the SRB community when provided with sodium lactate, sucrose or ethanol as carbon sources in complex Postgate C broth. These two analyses, as well as conventional methods, were applied to follow succession patterns in the laboratory scale reactors, and to determine the possible presence and relative abundance of microorganisms other than bacteria under sulfate reducing conditions. T-RFLP and BIOLOG™ Ecoplate analyses indicated a few dominant organisms in the community and a slight decline after a shift to another carbon source. Fluorescent hybridization showed higher numbers of SRB relative to the total microbial community than conventional culturing techniques. Furthermore, microscopic observations showed that not only SRB and other bacteria, but also yeast and filamentous fungi were integrated in a biofilm under sulfate reducing conditions. These microscopic observations were verified with fluorescent in situ hybridization (FISH) and yeast Live I Dead viability probes.
AFRIKAANSE OPSOMMING: Biologiese sulfaat-verwydering is met behulp van "n laboratoriumskaalmodel gesimuleer. Die doel van die navorsing was om die respons van "n mikrobiese gemeenskap met byvoorbeeld die relatiewe hoeveelheid van funksionele groepe op veranderinge in invloeiende medium samestelling te bestudeer. Spesifieke oligonukleotiedpeilers wat sulfaatreduserende bakterieë (SRB) in "n biofilmgemeenskap kan opspoor is gebruik. Die SRB gemeenskap is bestudeer met behulp van terminale-restriksiefragmentlengtepolimorfisme (TRFLP) en BIOLOGTM Ecoplate analise waar natriumlaktaat, sukrose of etanol as koolstofbronne toegevoeg is. Hierdie twee tipes analise en konvensionele metodes is aangewend om suksessiepatrone in die laboratoriumskaalreaktor te volg en die moontlike teenwoordigheid en relatiewe hoeveelheid van organismes, uitsluitende bakterieë, onder sulfaatreduserende kondisies te bepaal. Analise van T-RFLP en BIOLOGTM Ecoplate het aangedui dat In paar dominante organismes in die gemeenskap teenwoordig was, wat effens afgeneem het na verskuiwing na 'n ander koolstofbron. Fluoresserende hibridisasie het hoër getalle van SRB relatief tot die totale mikrobiese gemeenskap aangedui as konvensionele kultuur tegnieke. Mikroskopiese analises het verder getoon dat benewens SRB en ander bakterieë ook giste en filamentagtige swamme onder sulfaatreduserende kondisies in "n biofilm geïntegreer was. Hierdie mikroskopiese waarneminge is bevestig deur fluoresserende in situ hibridisasie (FISH) en gis Lewe / Dood lewensvatbaarheid peilers.
Jakobsson, Elsa. "Particle Removal from Chlorate Electrolyte." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-59489.
Full textDahiru, R. (Rufai). "CO₂ Removal from wood gas." Master's thesis, University of Oulu, 2013. http://urn.fi/URN:NBN:fi:oulu-201310301823.
Full textBin, Darwish Nawaf Naif. "Boron removal from saline water." Thesis, Swansea University, 2014. https://cronfa.swan.ac.uk/Record/cronfa42237.
Full textHepburn, Caroline Amy. "Removal of siloxanes from biogas." Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/9282.
Full textKoltuksuz, Gülsan Ülkü Semra. "Removal of hydrocarbons from wastewaters/." [s.l.]: [s.n.], 2002. http://library.iyte.edu.tr/tezler/master/kimyamuh/T000046.pdf.
Full textSundaram, Hari Prashanth. "SO₂ removal with coal scrubbing." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2035.
Full textTitle from document title page. Document formatted into pages; contains vii, 42 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 33-34).
Yarham, Carson, Urs Boeniger, and Felix J. Herrmann. "Curvelet-based ground roll removal." Society of Exploration Geophysicists, 2006. http://hdl.handle.net/2429/545.
Full textJensen, Keith R. "Effects of Integrated Fixed Film Activated Sludge on nitrogen removal in biological nutrient removal systems." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-01312009-063219/.
Full textGara, Ramos Rodriguez. "Nitrate and phosphate removal from aqueous solution by biochar and agroforestry residues." Thesis, KTH, Skolan för kemivetenskap (CHE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145955.
Full textMcCue, Terrence. "EVALUATION OF PREFERMENTATION AS A UNIT PROCESS UPON BIOLOGICAL NUTRIENT REMOVAL INCLUDING BIOKINETIC AND WASTEWATER PARAMETERS." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3031.
Full textPh.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering
Gnatenko, A. S., K. D. Aleksieieva, and К. А. Vasko. "Femtosecond fiber laser for hair removal." Thesis, Університет ім.Т.Г.Шевченка, 2015. http://openarchive.nure.ua/handle/document/8596.
Full textMcHugh, Allen David. "Effects of traffic removal on vertosols /." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17676.pdf.
Full textParini, Michael R. "Biofilm Removal Using Bubbles and Sound." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd958.pdf.
Full textMichen, Benjamin. "Virus removal in ceramic depth filters." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2011. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-66644.
Full textTokcaer, Emre. "Removal Of Lead Using Anaerobic Biomass." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1087600/index.pdf.
Full text5 to an equilibrium value of 7 &ndash
8. Large floc particles settling rapidly were formed after the ADS samples contacted with Pb(II) solution. The high Pb(II) removal capacities, and visual observations during the experiments indicated that precipitation is a dominant mechanism especially at low initial Pb(II) concentrations. FTIR studies showed that carboxyl groups present in the biomass surface of raw ADS were major functional groups in biosorption of Pb(II). The low capacity values attained at initial pH 2.0 indicated that there was a competition between Pb(II) species and hydrogen ions for carboxyl groups. Single and 3-stage fed-batch reactor systems were operated using raw ADS at different initial Pb(II) concentrations. The efficiency of reactor systems increased when 3-stage fed-batch configuration was used and an effluent Pb(II) concentration below 2 mg/L was reached from an initial value of about 200 mg/L.
Karabacak, Asli. "Sulphate Removal By Nanofiltration From Water." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612748/index.pdf.
Full textlkü
Yetis Co-advisor: Prof. Dr. Mehmet Kitis December 2010, 152 pages Excess sulphate in drinking water poses a problem due to adverse effects on human health and also due to aesthetic reasons. This study examines the nanofiltration (NF) of sulphate in surface water using a laboratory cross-flow device in total recycle mode. In the study, three NF membranes, namely DK-NF, DL-NF and NF-270, are used. The influence of the main operating conditions (transmembrane pressure, tangential velocity and membrane type) on the steady-state permeates fluxes and the retention of sulphate are evaluated. Kizilirmak River water is used as the raw water sample. During the experimental studies, the performance of NF is assessed in terms of the parameters of UVA254, sulphate, TOC and conductivity of the feed and permeates waters. Results indicated that NF could reduce sulphate levels in the surface water to a level below the guideline values, with a removal efficiency of around 98% with all three membranes. DK-NF and NF-270 membranes showed fouling when the surface water was fed directly to the system without any pre-treatment. MF was found to be an effective pretreatment option for the prevention of the membrane fouling, but no further removal of sulphate was achieved. Parametric study was also conducted. No change in flux values and in the removal of sulphate was observed when the crossflow velocity was lowered. The flux values were decreased as the transmembrane pressure was lowered
however there were not any decrease in the sulphate removal efficiency.
Chaudhry, Naeem Ashfaq. "Automatic Facial Occlusion Detection and Removal." Thesis, Umeå universitet, Institutionen för datavetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-61835.
Full textLiu, Yang. "Fluoride removal from zinc sulfate solution." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62913.
Full textApplied Science, Faculty of
Materials Engineering, Department of
Graduate
Odongo, Anthony. "Tar removal in hot gas streams." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/40498.
Full textKonduru, Ramakrishna Raju. "Color removal using low-cost adsorbents." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ30493.pdf.
Full textHan, Yiseon. "Arthromyces ramosus peroxidase catalyzed phenol removal." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0004/MQ34372.pdf.
Full textMulton, Lance Michael. "Removal of oil from produced waters." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ60239.pdf.
Full textOmer, Masoud. "Efficient routing of snow removal vehicles." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5169.
Full textTitle from document title page. Document formatted into pages; contains viii, 95 p. : ill. Includes abstract. Includes bibliographical references (p. 79-91).
Gaulin, Jean-Philippe. "Selective caffeine removal by microbial consortia." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80272.
Full textEffects of caffeine on microbial consortia were studied using denaturing gradient gel electrophoresis (DGGE), providing a community-scale view of changes in microbial consortia upon caffeine addition. Surprisingly, caffeine removal was achieved indigenously by the microbial consortium. Principal component analysis was used to analyze differences in DGGE banding patterns between control and caffeine-exposed mixed cultures.