Tesis sobre el tema "Industrial wastewater"

The remediation of industrial wastewater is highly challenging, difficult task, and demands highly efficient technologies. Electrochemical and ozonation technologies are among the most efficient methods in treating the industrial wastewater. The electrochemical generation of ozone can provide very high concentrations of the reagent in both the gas phase and solution. The aim of the research reported in this thesis was to develop durable and highly efficient Ni/Sb – SnO2 anodes to generate ozone and to investigate their efficiency in treating industrial wastewater. Different anode sizes were studied: 0.64 cm2, 6.25 cm2 and 24 cm2 using Ti mesh as substrate. With respect to the 0.64 cm2 anodes, replacing Sb and Ni chlorides with their respective oxides and adding Au or Pb had little or no effect upon the anodes electrochemical properties. The research showed that all 0.64 cm2 anodes were porous with dimensionalities < 2. However, the presence of the Au in the precursors reduced the ozone current efficiency. The 0.64 cm2 anodes achieved ozone current efficiencies of ca. 30% at cell voltages of 2.7 V routinely. Using 6.25 cm2 anodes prepared with the Sb and Ni oxides in the precursor solution and annealed at 550 oC gave electrodes which were durable for more than 200 h operation at a current density of 100 mA cm-2 (corresponding to cell voltages of ca. 3 V) in 1 M HClO4. These current densities and service life are the highest reported for Ni/Sb – SnO2 anodes. A service life of more than 600 h was achieved in a later investigation. The 6.25 cm2 anodes achieved current efficiencies up to 38%, with 25 -30% routinely achievable. The presence of Ni is crucial for ozone generation with optimum Ni content (in the precursor solution) of ca. 1.04 at % Ni. The optimum annealing temperature was 460 oC. In terms of the 24 cm2 anodes, they were employed to prepare membrane electrode assemblies (MEA’s) for ozone generation from deionised (Millipore) water. MEA’s with air breathing cathodes suffered from flooding of the cathode pores, resulting in limited current densities. MEA’s with hydrogen – evolving cathodes did not suffer from flooding or low current densities. Overall, current efficiency of ca. 36 % at cell voltage of 1.6 V (40 mA cm-2) with Millipore water as anolyte was obtained using MEA’s with air breathing Preface vii cathodes; corresponding to a power consumption of 16.7 kWh (kg O3)-1 which is the lowest reported for electrochemical ozone generation of any description, MEA’s with H2 cathodes achieved a current efficiency of 33% at ca. 25 mA cm-2 and a cell voltage of 2.5 V, corresponding to ca. 25 kWh (kg O3)-1. The 0.64 cm2 anodes were used to decolourise solutions containing : Reactive Blue 50 (RB50), Naphthol Green B (NGB) and Congo Red (CR) dyes. The operational conditions of the decolourisation process were investigated and the optimum conditions were: 3 g dm-3 Na2CO3 as electrolyte, 50 mA cm-2 and 200 mg dm-3 dye in Millipore water. RB50 solutions could be decolourised completely within 20 min, with 90% of the COD removal after 60 min, NGB and CR proved more refractory. Indirect oxidation mediated by OH radicals was the main decolourisation mechanism at the Ni/Sb – SnO2 anodes. Ozonation, UV254 irradiation and O3/UV were used to decolourise the dye solutions for comparison with electrochemical decolourisation at the Ni/Sb – SnO2 anodes. Ozone was generated by MEA – based electrochemical cells and ozonation occurred in a bubble column reactor (BCR). The O3/UV combination was the most efficient, achieving 100 % decolourisation of RB50 and NGB solutions within 20 and 35 min, respectively, with 33% and 64% COD removal after 60 min.

Wastewater effluent produced in the fiberglass manufacturing industry contains a significant amount of total suspended solids. Environmental regulations require pretreatment of effluent before it is discharged to the municipal wastewater treatment plant. Chemical precipitation by coagulation and flocculation is the method of pretreatment used at the Vetrotex CertainTeed Corporation (VCT). A treatability study was conducted to determine conditions at which the VCT Wastewater Pretreatment Plant could operate to consistently achieve a total suspended solids concentration ≤ 200-mg/L. Jar tests varied pH, polymer dosage, and ferric sulfate dosage. Total suspended solids and turbidity were measured to evaluate treatment performance. The data were used to determine an optimum set of conditions under project guidelines. Of twelve polymers screened, BPL 594 was selected as the most effective polymer. For cost efficiency in the wastewater pretreatment operation, recommendations suggested that treatment chemical injection be electronically controlled according to turbidity of the treated effluent.

A study was undertaken to investigate developing biofilms in a petrochemical wastewater treatment plant encompassing the architecture, microflora and the chemical nature of the matrix. Biofilms were developed on glass slides immersed in the activated sludge unit and analysed at known time intervals using a range of techniques. Initially, biofilms were investigated using conventional and emerging microscopic approaches to select a suitable technique. Scanning Confocal Laser Microscopy (SCLM) allowed visualisation of biofilms in situ with minimal background interference and non-destructive and optical sectioning which were amenable to quantitative computer-enhanced microscopy. SCLM was superior over Light microscopy and Scanning Electron Microscopy. This study demonstrated biofilm growth, presence of extracellular polymer substances (EPS) in early biofilms associated with cells and the development of porous nature of mature biofilms including channel-like structures. Overall new information has been obtained on developing biofilms in an Australian petrochemical wastewater treatment plant<br>Doctor of Philosophy (PhD) (Biological Sciences)

Quality control of wastewater is an important treatment process more so now, tnan ever before. Due to an extremely unpredictable nature of the wastewater, which is a mixture of both inorganic and organic waste, it is very difficult to neutralise. Two approaches have been proposed in developing alternative control strategies as suggestions for the pH control of the wastewater in an industrial plant. The first is to develop a mathematical model of a continuously stirred tank reactor (CSTR) with a possible use of MATLAB®. Three different control methods (linear, nonlinear and adaptive) are subject to vigorous theoretical testing and are proposed as a possible solution. The second, a parallel approach, has been to build a laboratory scale experimental reactor using a seven litre continuously stirred tank with monitors for influent flow, influent pH and reactor tank pH. Results suggest that a more sophisticated controller than the simple PID control, currently in operation, could lend Itself to overcoming the problem of persistent large spikes in the pH of the influent. Further work would consider the implementation of these results to the actual industrial wastewater treatment plant.

In metal machining processes, the regulation of heat generation and lubrication at the contact point are achieved by application of a fluid referred to as metalworking fluid (MWF). This has the combined features of the cooling properties of water and lubricity of oil. MWFs inevitably become operationally exhausted with age and intensive use, which leads to compromised properties, thereby necessitating their safe disposal. Disposal of this waste through a biological route is an increasingly attractive option, since it is effective with relatively low energy demands when compared to current physical and chemical options. However, biological treatment is challenging since MWF are chemically complex, including the addition of toxic biocides which are added specifically to retard microbial deterioration whilst the fluids are operational. This makes bacterial treatment exceptionally challenging and has stimulated the search and need to assess technologies which complement biological treatment. In this study the remediation, specifically of the recalcitrant component of a semi-synthetic MWF, employing a novel hybrid treatment approach consisting of both bacteriological and chemical treatment, was investigated. Three chemical pre-treatment methods (Fenton’s oxidation, nano-zerovalent iron (nZVI) oxidation and ozonation) of the recalcitrant components followed by bacterial degradation were examined. The synergistic interaction of Fenton’s-biological oxidation and nZVI-biodegradation led to an overall COD reduction of 92% and 95.5% respectively, whereas pre-treatment with ozone reduced the total pollution load by 70% after a post-biological step. An enhancement in biodegradability was observed after each of the chemical treatments, thus facilitating the overall treatment process. The findings from this study established that the use of non-pathogenic microorganisms to remediate organic materials present in MWF wastewater is a favourable alternative to energy demanding physical and chemical treatment options. However, optimal performance of this biological process may require chemical enhancement, particularly for those components that are resistant to biological transformation.

CJP Solutions och Waste Handling and Management (WHAM) är två företag i Melbourne, Australien, som utvecklar en process för återvinning av bioslam från Melbourne Waters reningsverk. Slammet är förorenat med metaller från industriellt avloppsvatten som har behandlats tillsammans med det kommunala avloppsvattnet. Företagen sökte en hållbar biologisk process inkluderande alger för att rena och fånga in rökgaser från pyrolisering och förbränning av det förorenade slammet. I det här examensarbetet har en teknisk lösning utformats, tillverkats och experimentellt prövats på plats under tjugo veckor i Melbourne, med mål att: mäta gas- och vattenreningsprestanda. Efter åtta veckors inledande litteraturstudie omfattande koldioxidinfångst samt algbiologi med industriell tillämpning fattades beslut om att i första hand använda mikroalgen Chlorella vulgaris, för dess robusta egenskaper samt potential för snabb tillväxt. Utöver Chlorella v. odlades en blandning lokala algkulturer tillsammans med Chlorella v. fram, och prövades parallellt vid de efterföljande experimenten. Experimenten utfördes under tre veckor vid energiföretaget AGLs biogasdrivna kraftvärmeverk, på Melbourne Waters Western Treatment Plant. I experimentet leddes orenade rökgaser genom ett system för kylning, filtrering och kompression, till algodlingarna. Algodlingarna var utformade i två separata system, det ena bestående av sju vertikala 25 liters plastkolonner, det andra av en 250 liters bassängodling. Systemen blandades genom luft- och rökgasinsprutning, samt genom mekaniserad omrörning. Algerna odlades i delvis renat avloppsvatten. Val av tekniska lösningar baserades på låga omkostnader, enkel konstruktion, komponenternas tillgänglighet, samt en tre veckors tidsfrist till att utforma och tillverka systemen.<br>CJP Solutions in collaboration with Waste Handling and Management (WHAM), two companies based in Melbourne, Australia, are currently developing a process to treat and recycle biosolids left over from the wastewater treatment process at Melbourne Water’s Western Treatment Plant. The biosolids are contaminated with heavy metals from industrial wastewater, being treated together with municipal wastewater. The companies are looking for a sustainable solution for sequestering flue gases from pyrolysis of the biosolids, into an algal biomass. In this Master Thesis project, a technical solution has been designed, constructed and tested on site over the course of twenty weeks in Melbourne, the goal being to determine gas and water cleanup performance. After eight weeks of initial literature review covering CO 2-sequestration and industrial applications of algae cultivation, the microalgae Chlorella vulgaris was chosen as the main strain to be used, due to it being robust and having a high growth rate. In addition to the Chlorella v. culture, a mix consisting of local algae cultures together with Chlorella v. was also cultivated throughout the experiments. The experiments were carried out during three weeks at AGL’s biogas power plant, at the Western Treatment Plant. Untreated exhaust gas was led through a system of cooling, filtration, and compression, into the two separate algal culture systems. One consisted of seven 25 litre plastic column reactors, the other of a 250 litre pond reactor. The systems were mixed through air bubbling, exhaust gas inlet, as well as by a mechanical stirrer in the pond reactor. The algae were grown in partially treated wastewater. Factors determining the system design included simplicity in construction, use of cheap, available materials, as well as a three week design and construction deadline.<br>www.ima.kth.se

An investigation of biohydrogen production from glucose by Clostridium beijerinckii was conducted in a synthetic wastewater solution. A study examining the effect of initial pH (range 5.7 to 6.5) and COD loading (range 1 to 3 g/L) on the specific conversion and hydrogen production rate has shown interaction behaviour between the two independent variables. Highest conversion of 10.3 mL H2/(g COD/L) was achieved at pH of 6.1 and COD of 3 g/L, whereas the highest production rate of 71 mL H2/(h*L) was measured at pH 6.3 and substrate loading of 2.5 g COD/L. In general, there appears to be a strong trend of increasing hydrogen production rate with an increase in both substrate concentration and pH. Butyrate (14% to 63%), formate (10% to 45%) and ethanol (16% to 40%) were the main soluble products with other volatile fatty acids and alcohols present in smaller quantities. Absence of the key nutrients biotin, MgSO4.7H2O and FeSO4.7H2O caused a significant decrease in hydrogen yield when compared to the results obtained under standard synthetic wastewater conditions, though no significant difference was observed when concentrations of biotin, MgSO4.7H2O, K2HPO4, KH2PO4, were decreased partially. Preliminary experiments with wastewater effluent obtained from a yogurt manufacturer gave poor biohydrogen production.<br>Ce projet de recherche porte sur la production de biohydrogène par le Clostridium beijerinckii en utilisant comem subtrat le glucose contenu dans une eau usée synthétique. Une étude de l'effet du pH initial (intervalle de 5.7 à 6.5) et de la charge organique (intervalle de DCO de 1 à 3 g/L) sur la conversion spécifique et le taux de production d'hydrogène a démontré des interactions entre ces deux variables indépendantes. La conversion la plus élevée, 10.3 mL H2/(g COD/L), a été observée à un pH de 6.1 et une DCO de 3 g/L alors que le plus haut taux de production, 71 mL H2/(h*L), a été obtenu à un pH de 6.3 et une DCO de 2.5 g/L. La tendance globale indique que le taux de production d'hydrogène augmente lorsque la charge organique et le pH augmentent. Le butyrate (14% à 63%), le formate (10% à 45%) et l'éthanol (16% à 40%) formaient les principaux produits solubles. Des acides gras volatiles et des alcools ont également été observés en faibles quantités. L'absence de nutriments essentiels tels que biotine, le MgSO4.7H2O et le FeSO4.7H2O a causé une diminution significative de la production d'hydrogène comparativement aux résultats obtenus à l'aide des conditions de référence utilisées pour la solution d'eau usée synthétique. Aucun impact significatif n'a toutefois été observé lorsque la concentration de ces nutriments était diminuée que partiellement. Des essais préliminaires à partir d'eau usée provenant d'une usine de production de yogourt ont indiqué une faible production d'hydrogène à partir de ce substrat.

The overall goal of the thesis was to develop and optimize the moving bed biofilm reactor technology under anaerobic conditions. The thesis work was divided into two different series of experiments. Hence, at first, the reactor start-up on synthetic substrate was evaluated and it was proven that the anaerobic moving bed biofilm reactor technology could successfully treat concentrated wastewater. Subsequently, a study on Fort Garry Brewery wastewater was conducted to optimize the process for a typical North American industrial wastewater. The aim was successfully achieved and a potential design to treat Fort Garry Brewery wastewater was developed. The anaerobic moving bed biofilm reactor was found to be capable in treating brewery wastewater with potential savings to the industry paying surcharges for discharging wastewater over the city sewer bylaw limits.<br>October 2016

The biological treatment of wastewaters from an industry was studied. Among the more important wastewater constituents of concern were high levels of suspended solids, due to graphite and nitrocellulose, the solvents, ethanol and acetone, and nitroglycerine (NG). The goal of this project was divided into four objectives. The impacts of graphite on a microbial population were evaluated. Sequencing batch reactors (SBRs) were used to monitor the effects of graphite on mixed liquor suspended solids (MLSS), removal of soluble chemical oxygen demand (sCOD), and specific oxygen uptake rates (sOUR). Graphite appeared to have no adverse effect on the microbes. The potential benefits of adding sucrose, nitrogen, and phosphorus to SBRs were evaluated. The MLSS was maintained at 1,250 mg/L, similar to the microbial population in the suspended growth system at the industry. Sucrose addition increased the sCOD removals and sOUR. No direct effect was observed with the addition of nitrogen and phosphorus. The treatability of acetone and ethanol was studied through sOUR and batch testing to determine bacterial response to solvents. Both solvents were utilized by the microbes. The concentrations tested proved to be beneficial, not inhibitory. Ethanol and a 50/50 mixture of acetone and ethanol were more viable substrates than acetone. NG treatability was examined under anoxic and aerobic conditions in SBRs and batch biological reactors. NG degradation occurred under anoxic conditions, but was more favorable in aerobic environments. NG was degraded in all SBR tests to below detection limit (0.5 mg/L); therefore, the optimal treatment could not be determined.<br>Master of Science

Microbial fuel cells (MFCs) hold great promise for the simultaneous treatment of wastewater and electricity production. However, the electricity recovery needs improvement if MFCs are to compete with already established technologies e.g. anaerobic digestion. The aim of this study was to investigate ways of enhancing electricity recovery from (synthetic) industrial wastewater. Initial studies investigated the use of defined cocultures as a way of improving turnover of substrate and hence electricity produced by exploiting mutualistic relationships such as syntrophy or ability of facultative microoganisms (Saccharomyces cerevisiae) to consume residual oxygen from the anode. A coculture of Shewanella oneidensis and Clostridium beijerinckii, investigated here for the first time, gave a power production of 87 mW m-2 compared to 48 mW m-2 for S. oneidensis alone or 60 mW m-2 for C. beijerinckii alone. Substrate degradation was also improved significantly from 20% (S. oneidensis alone) to 67% using the coculture. Similar improvements were observed for novel cocultures of G. sulfurreducens, S. cerevisiae and C. beijerinckii as well as cocultures of C. beijerinckii, S. oneidensis and S. cerevisiae. To improve electricity recovery from MFCs, mechanisms of electron transfer need to be understood. The contribution of direct electron transfer mechanisms to overall electron transfer was investigated for the first time by restricting S. oneidensis cells close to or away from an anode electrode. A maximum power output of 114 mW m−2 was obtained when cells were retained close to the anode. This was 3.5 times more than when the cells were separated away from the anode. This result was corroborated by another study where S. oneidensis cells were entrapped in alginate gels. To further investigate the contribution of the c-type cytochromes forming the Mtr pathway to extracellular electron transfer, Rapid DNA Prototyping Assembly was used for the first time to assemble Mtr-pathway coding genes individually or as operons. The different constructs were overexpressed in S. oneidensis and heterologously expressed in E. coli and power production compared with the wild type strains. The best power generated was from the mtrAB S. oneidensis strain (144 mW m-2) and from the mtrCAB E. coli strain (24 mW m-2). Since electricity production is linked to exoelectrons forming a biofilm on the anode, ways of enhancing biofilm formation were sought. The quorum sensing molecule N (-3-oxodecanoyl)-L-homoserine lactone of different concentrations was for the first time exogenously added to MFCs and its effect on biofilm formation and power production determined. The results were compared with control experiments without N (-3-oxodecanoyl)-L-homoserine lactone. The results indicated that power production of 184 mW m-2 , the highest obtained of all approaches taken in this investigation, could be obtained when 10 uM of the chemical was added compared to 56 mW m-2 for the control, with significant increases in biofilm density. Taken together, these results highlight the importance of using defined cocultures (e.g. for bioaugmentation of working MFCs), direct electron transfer mechanisms, overexpression of the Mtr-pathway and need to increase biofilm density on anode surfaces, for enhancing electricity recovery in microbial fuel cells.

La gestió de l'aigua residual és una tasca complexa. Hi ha moltes substàncies contaminants conegudes però encara moltes per conèixer, i el seu efecte individual o col·lgectiu és difícil de predir. La identificació i avaluació dels impactes ambientals resultants de la interacció entre els sistemes naturals i socials és un assumpte multicriteri. Els gestors ambientals necessiten eines de suport pels seus diagnòstics per tal de solucionar problemes ambientals.<br/>Les contribucions d'aquest treball de recerca són dobles: primer, proposar l'ús d'un enfoc basat en la modelització amb agents per tal de conceptualitzar i integrar tots els elements que estan directament o indirectament involucrats en la gestió de l'aigua residual. Segon, proposar un marc basat en l'argumentació amb l'objectiu de permetre als agents raonar efectivament. La tesi conté alguns exemples reals per tal de mostrar com un marc basat amb agents que argumenten pot suportar diferents interessos i diferents perspectives. Conseqüentment, pot ajudar a construir un diàleg més informat i efectiu i per tant descriure millor les interaccions entre els agents. En aquest document es descriu primer el context estudiat, escalant el problema global de la gestió de la conca fluvial a la gestiódel sistema urbà d'aigües residuals, concretament l'escenari dels abocaments industrials. A continuació, s'analitza el sistema mitjançant la descripció d'agents que interaccionen. Finalment, es descriuen alguns prototips capaços de raonar i deliberar, basats en la lògica no monòtona i en un llenguatge declaratiu (answer set programming).<br/>És important remarcar que aquesta tesi enllaça dues disciplines: l'enginyeria ambiental (concretament l'àrea de la gestió de les aigües residuals) i les ciències de la computació (concretament l'àrea de la intel·ligència artificial), contribuint així a la multidisciplinarietat requerida per fer front al problema estudiat. L'enginyeria ambiental ens proporciona el coneixement del domini mentre que les ciències de la computació ens permeten estructurar i especificar aquest coneixement.<br>Wastewater management is a very complex task. There is a high number of known and an increasing number of unknown pollutants whose individual and collective effects are very difficult to predict. Identifying and evaluating the impacts of environmental problems resulting from the interactions between our social system and its natural environment is a multifaceted critical issue. Environmental managers require tools to support their diagnoses for solving these problems. The contributions of this research work are twofold: first, to propose the use of an agent-based modelling approach in order to conceptualize and integrate all elements that are directly or indirectly involved in wastewater management. Second, to propose a framework based on argumentation that allows to reason effectively. The thesis provide some real examples to show that an agent-based argumentation framework can deal with multiple interests and different agents' perspectives and goals. This help to build a more effective and informed dialog in order to better describe the interaction between agents. In this document we first describe the context under study, scaling down the global river basins system to the urban wastewater systems and giving some more details for the specific scenario of industrial wastewater discharges. Then, we analyze the system in describing intelligent agents that interact. Finally, we propose some reasoning and deliberation prototypes by using an argumentation framework founded on non-monotonic logics (i.e. permitting to learn things that were previously not known) and the answer set programming specification language (i.e. a declarative programming language). It is important to remark that this thesis links two disciplines: environmental engineering (specifically the area of wastewater management) and computer science (specifically the area of artificial intelligence), contributing to the required multidsciplinarity needed to confront the complexity of the problem under study. From environmental engineering we obtain the domain knowledge whereas the computer science field permits us to structure and specify this knowledge.

The results of this study show that novel mesoporous carbons were obtained as inverse replica of SBA-15, HMS and MCM-41 silica templates, with a large pore diameter (2-4 nm), a BET surface area of 1867, 874 and 910 m2g –1 respectively for CA_SBA-15_LPG_105, CA_HMS_LPG_80 and CA_MCM- 41_LPG_80 with bimodal pore size distribution (PSD) in the mesopores range. The results obtained show that mesoporous carbon with graphitic structures can be synthesized via the LPG route.

Water management has become a very vital issue for process engineers because of the stringent environmental regulation. A systematic study of water saving opportunities in process industries is conducted in this research using process integration approach (specifically water pinch analysis as a tool). Within this work, reuse/recycle and regeneration-reuse/recycle schemes are considered. Moreover, a special attention is given to the threshold problems. To facilitate these studies, MATLAB has been employed as a programming tool.

China has long faced the exponential increase of wastewater. Therefore, sludge as the byproduct of wastewater treatment is a worldwide and difficult problem to treat and dispose. Many cities in China are trying to find an appropriate method of achieving this. However, due to a lack of funding, technology and research, some methods suitable for local conditions are still not available, even in the most modern and biggest cities in China. This thesis is intended to describe the method used for the treatment and disposal of sludge from industries now in Shanghai, Beijing and Chongqing. Compared with these three cities, Beijing produces more sludge per day, while Shanghai has the least sludge production. Further, the industrial waste piping system is not separated from the domestic system in these three cities. Moreover, the percentage of treated sludge is still very low in Shanghai, Beijing and Chongqing. Among these three cities, even the highest treatment rate of sludge is 35.41% (Beijing). The lowest is only 10.08% (Chongqing). Considering that much more sludge will be produced in the next a few years, the current situation in these three cities presents a stern challenge. Also, a calculation about the cost of disposal of sludge in these cities is included in this thesis. Incineration is most expensive method of disposal of sludge in China, while composting is the cheapest. Considering the huge population, the current technology and the economic conditions in China, composting is the best option for the disposal of sludge.

Due to the extensive use of xenobiotic azo dyes in the colour industry and their proven mutagenic and cytotoxic nature, their treatment prior to discharge is essential and is legally enforced. However, currently used wastewater treatment technologies such as activated sludge systems, anaerobic digestion, electrochemical destruction, adsorption and membrane filtration are ineffective in removing azo dyes due to reasons such as inefficient dye degradation, slow degradation kinetics, toxic metabolite formation, inhibitory costs and generation of secondary waste streams. Therefore, in this study, microbial fuel cells (MFCs) were studied as possible systems that could effectively degrade azo dyes with an additional benefit of concomitant biogenic electricity generation. The co-metabolic degradation of the model azo dye Acid Orange-7 (AO-7) using Shewanella oneidensis and mixed anaerobic cultures in MFC was carried out with particular emphasis on AO-7 degradation kinetics in the initial study. The effect of using various carbon sources including cheaper complex ones such as molasses and corn steep liquor as electron donors for azo dye degradation in MFCs was also investigated. The outcomes of this study demonstrated that fast AO-7 reductive degradation kinetics using cheap, sustainable co-substrate types can be achieved with concomitant bioelectricity generation in two-chamber MFCs. Power densities up-to 37 mWm-2 were observed in the two-chamber MFC system during AO-7 decolourisation. Co-metabolic reductive degradation of azo dye mixtures using dye acclimated mixed microbial populations under industrially relevant conditions (high temperatures and salinities) and changes in microbial community structure in the MFCs in presence of complex azo dye mixtures in two-chamber MFCs was investigated. The outcomes of this work demonstrated that efficient colour and organic content removal can be achieved under high temperatures and moderate salinities using azo dye adapted mixed microbial populations in two-chamber MFCs. Microbial community analysis of the original anaerobic consortium and the azo dye adapted microbial culture following MFC operation indicated that both cultures were dominated by bacteria belonging to the phylum Firmicutes. However, bacteria belonging to phyla Proteobacteria and Bacteroidetes also became selected following MFC operation. Peak power densities up-to 27 mWm-2 were observed in this study during decolourisation of complex azo dye mixtures. The complete degradation of the azo dye AO-7 using a sequential reductive – oxidative bioprocess in a combined MFC-aerobic bioreactor system operating at ambient temperature in continuous mode was studied. The outcomes of this study demonstrated that the azo dye AO-7 can be fully decolourised and degraded into non-toxic and simpler metabolites. Maximum power densities up-to 52 mWm-2 were observed during azo dye degradation. A modular scale-up version (with a volumetric scale-up factor of 6) of the two stage integrated bioreactor system demonstrated the capability to efficiently treat two types of real wastewater originating from colour industry without any apparent deterioration of reactor performance in terms of dye decolourisation and COD removal. The use of applied external resistance (Rext) and redox mediators as tools for enhancing azo dye degradation kinetics in dual chamber MFCs was studied. The outcomes of this work suggest that azo dye reductive degradation kinetics in MFC anodes can be influenced by varying Rext. Furthermore, AO-7 reductive degradation kinetics was improved in a concentration-dependent manner by exogenous addition of two electron shuttling compounds anthraquinone-2,6-disulfonic acid and anthraquinone-2-sulfonic acid in MFC anodes. The overall outcomes of this study implies that MFCs could be successfully applied for achieving enhanced azo dye reductive biodegradation kinetics in MFC anodes coupled with concomitant bioelectricity generation. It further demonstrated that MFC systems can be successfully integrated with existing wastewater treatment technologies such as activated sludge systems for complete degradation and toxicity removal of azo dyes and their biotransformation metabolites.

Master of Science<br>Department of Biological and Agricultural Engineering<br>Stacy L. Hutchinson<br>The energy sector needs to transition to renewable energy to provide energy and economic security in the future (Murray & King, 2012). Liquid biofuels are an important renewable fuel in this transition because they are the preferred renewable energy source in the transportation sector (Lange, 2007), and the only renewable energy alternative for the aviation industry [International Air Transport Association (IATA), 2015]. Biofuels produced from food crops (first-generation biofuels) are being produced at an industrial scale, but they create several environmental and social conflicts (Mohr & Raman, 2013). Currently, there is a demand for the next generation of biofuels to resolve the environmental and social conflicts associated with first-generation biofuels. Salicornia, a salt tolerant oil seed crop (Panta et al., 2014), is one feedstock that might be able to resolve some of those conflicts because it can be irrigated with saline water (Warshay et al., 2017). The ability of Salicornia to tolerate saline environments suggests that it might be able to be cultivated in a hydroponic system designed to treat industrial wastewater. A hydroponic system designed to treat industrial wastewater and produce Salicornia as a biofuel feedstock could prevent some of the detrimental effects of industrial sources of saline water on terrestrial and aquatic ecosystems (Gerhart et al., 2006), and produce a feedstock that resolves some of the issues with first-generation biofuels. The first step in the development of the proposed hydroponic system is to determine if Salicornia can be cultivated with industrial wastewater in a hydroponic system. Studies were conducted with two sources of industrial wastewater, Flue Gas Desulfurization (FGD) wastewater and Cooling Tower Blowdown Water (CTBW), to determine how the composition of water affects the germination, survivability, early seedling growth, and lignocellulosic composition of Salicornia. The composition of water was shown to have no effect on seed germination and visual signs of phytotoxicity. These studies found that full strength CTBW and 20% FGD wastewater could be used to cultivate Salicornia in a hydroponic system if nutrients are added. Full strength FGD wastewater was shown to have a negative impact on seedling growth. These studies also found that Salicornia is not a good lignocellulosic biofuel feedstock because of its low lignocellulosic composition (e.g. 14.9-9.1% glucan, 13.2-6.7% xylan, 5.2-2.4% arabinan, and 9.8-6.2% lignin). However, a large percentage of the extractives content is unidentified and could have a monetary value. Additional research is needed to determine if a hydroponic system that cultivates Salicornia is able to provide any water quality treatment.

Upset events due to the inflow of toxic chemicals are a critical issue for wastewater treatment facilities. Understanding the source-effect relationship of toxic chemicals can facilitate the prevention or improved reaction to upset events. Part one of this study was conducted to investigate the source of upset events at a regional industrial wastewater treatment plant (WWTP). Part two of this study determined the process performance effects of two chemical shocks, cyanide (zinc-cyanide complex) and pH, on nitrifying and non-nitrifying activated sludge. A modified respirometric assay protocol was developed to allow the industrial WWTP to screen industrial wastewaters for inhibitory properties. All five industrial wastewaters tested revealed inhibitory properties. Large day-to-day variations were found, illustrating the need for a large database of results for comparison over time. Additionally, a small volume contributor, that was thought by the utility to be an unlikely source of problems, contributed significantly to the wastewater oxygen demand and demonstrated inhibitory properties. The modified respirometric procedure enabled the WWTP to identify possible industrial sources that could cause an upset event. Lab-scale sequencing-batch reactors were used to determine the effects of cyanide and pH shock on activated sludge. Three reactors were shocked with increasing weak-acid complexed zinc cyanide or pHs of 5, 9, and 11. The resulting effects were compared to an un-shocked control reactor. It was found that respiration and nitrification were affected by the zinc cyanide complex, while COD removal, effluent TSS and dewaterability were not. Recovery was seen in less than 2 X solids residence time (SRT) for the nitrifying biomass and within 3 X SRT for the non-nitrifying biomass. The results of the pH experiment showed that the pH 11 shock affected the settleability, nitrification, COD removal, and effluent TSS levels of the reactors, while pH 5 and pH 9 shocks had no effect. Recovery was seen within 3 X SRT for both the nitrifying and non-nitrifying systems.<br>Master of Science

The focus of this thesis is primarily on nitrogen removal and secondarily on heavy metal accumulation in unsaturated and saturated vertical flow constructed wetlands (VFCWs) treating inorganic industrial wastewater. This thesis is divided into an experimental component and a case study component. Three research themes are presented within the scope of this thesis. The first theme involves the study of nitrification and denitrification and the characterisation of the respective bacterial communities in unsaturated and semi-saturated VFCWs. The identification of functional bacteria with the aid of polymerase chain reaction (PCR) based molecular techniques and the effect of salinity (NaCl) on these bacterial groups is also contained within this theme. The second theme is the use of low cost carbon sources to improve denitrification and nitrogen removal in saturated VFCWs. The third theme of this study is the performance of large scale VFCWs operating at CSBP Ltd, a chemical and fertiliser manufacturer based in Kwinana, Western Australia. The performance of the systems is assessed in regards to nitrogen and heavy metal removal. This theme also covers design and operational recommendations for improved nitrogen removal. Laboratory scale VFCWs planted with Schoenoplectus validus were used to assess the impact of increasing salinity (up to 40gNaCl/L) on nitrification and on ammonia oxidising bacteria (AOB). Ammonia removal above 90% could be achieved in the fresh and saline wetlands when these were operated under a hydraulic loading rate of 11cm/d. This represented a removal rate in the order of 12gNH3-N/m2/d. The gradual increase in salinity to 40gNaCl/L did not impact ammonia oxidation whereas the sudden increase (shock load) to 30gNaCl/L negatively impacted ammonia removal in the short term. Investigation of the microbial populations by terminal restriction fragment length polymorphism (T-RFLP) performed along with cloning and sequencing revealed that the increase in salinity selected for Nitrosomonas sp Nm 107-like (Nitrosococcus mobilis) and Nitrosospira sp 9SS1-like (Nitrosospira multiformis) AOB while other groups were eliminated or only present in very low proportions. Nitrification and denitrification were further studied and the AOB and denitrifying bacterial (DB) community analysed in unplanted, fresh and saline, semi-saturated VFCWs dosed with acetic acid as carbon source. The semi-saturated design allowed nitrification to occur in the unsaturated sand layer and denitrification to occur in the saturated drainage layer where organic carbon was added, resulting in a high nitrogen removal. Nitrogen removal rates were on average 13.6gN/m2/d and 12.7gN/m2/d for the fresh and saline systems, respectively. Total nitrogen removal was significantly higher in the fresh system than in the saline system. The presence of salt, however, did not impact nitrate or COD removal and similar nitrate and COD concentrations were obtained in both wetlands. The gram-negative DB were also similar in both wetlands and dominated by representatives of the α and β-proteobacteria. The feasibility of using carbon rich wastewater from a soft drink manufacturer (COD = 70,000mg/L), as exogenous carbon source to improve denitrification and nitrogen removal in saturated VFCWs treating high nitrate wastewater was tested. The addition of the carbon rich wastewater significantly increased nitrate removal from 23% to 65% and total nitrogen from 53% to 76%. Neither effluent ammonia nor effluent COD were affected by the addition of the carbon rich wastewater. Combining industrial wastewaters to improve treatability has proven to be cost effective and good example of industrial synergy with both economical and environmental benefits. The case study covered the full scale treatment wetlands at CSBP Ltd. Firstly, heavy metal distribution, nitrogen removal performance and the AOB were analysed in the 1.3ha saturated surface VFCW, which has been operational since 2004. Secondly, the design rationale of two parallel nitrifying VFCWs, 0.8ha each, commissioned at CSBP Ltd in 2009 is described and the results from the first year of operation analysed. The distribution of bioavailable Cu and Zn in the top sediment layer followed a horizontal profile with significantly higher concentrations near the inlet pipe than at the farthest location. The average total Cu concentration in the sediment at the 2m location has reached the 65mg/kg trigger value suggested by the Interim Sediment Quality Guidelines (ANZEEC 2000), indicating that increasing Cu levels could become toxic to plants and bacteria. From September 2008 to October 2009, the overall NH3-N and TN removal rates were 1.2gNH3-N/m2/d and 1.3gTN/m2/d, respectively. The 1.3ha wetland was operated in a sequencing batch mode, receiving highly fluctuating batch volumes and nitrogen concentrations. The majority of AOB sequences obtained were most similar to Nitrosomonas sp., while Nitrosospira sp. were less frequent. The two VFCWs added to the treatment train in 2009 were designed assuming an NH3-N removal rate of 4.5gNH3-N/m2/d. Monitoring of the first year of data revealed that the cells operated under hydraulic and mass overloads. Ammonia oxidation was slightly higher than initially anticipated with the overall removal rate for the new cells being 5gNH3-N/m2/d. Since commissioning of the new cells ammonia discharges have been greatly reduced. Overall, this thesis has demonstrated that vertical flow constructed wetlands can be effectively applied for the treatment of inorganic industrial wastewaters containing nitrogen. These systems have proven to harbour diverse salt tolerant nitrogen transforming bacteria, allowing them to operate reliably under varying salinities.

Roughly the same volume of water that rushes over the Niagara Falls is produced as wastewater in North America. This wastewater is treated through a variety of means to ensure that it can be safely returned to the natural ecosystem. This thesis examines two novel means for this treatment, one biological and one physical-chemical in nature, namely, Rotating Algae Biofilm Reactor treatment and expanded shale augmented coagulation-flocculation. Rotating algae biofilm reactors (RABRs) support biofilm algae growth, and in turn, the algae take up harmful contaminants from the wastewater. This system was tested in wastewater from petroleum refining operations. The efficacy of the RABR system was compared with a traditional method of wastewater treatment, open pond lagoons, where wastewater is open to sunlight and algae growth occurs in suspension as compared to the biofilm formed by the RABR system. The RABR treatment demonstrated a statistically significant increase in removal of three constituents in wastewater that are harmful to the environment: nitrogen, phosphorus, and suspended solids. Additionally, the RABR treatment demonstrated increased biomass production. This biomass can be converted into a variety of bioproducts including biofuels, agricultural feed, and nutraceuticals. This study is the first demonstration of this system in petroleum refining wastewater. Currently, many wastewater treatment facilities use coagulation-flocculation to remove suspended solids from the wastewater. To achieve this removal, coagulants are added to the wastewater, which removes surface charges of the suspended particles, allowing particles in solution to coalesce and settle by gravity out of solution. One common coagulant added to wastewater is ferric sulfate. This study demonstrated that the addition of a new compound, expanded shale, to ferric sulfate could greatly improve the efficacy of the existing ferric sulfate coagulation system.

This research investigated the efficiency of several treatment methods such as ultrafiltration membrane, photo-Fenton and adsorption process using biosorbents, individually and as a combined integrated system, for industrial oily wastewater treatment. Different oily wastewater qualities (petroleum refinery effluent, resultant effluent, canola oil effluent and synthetic oily wastewater) were used to understand and suggest a cost effective and efficient treatment technology.

碩士<br>逢甲大學<br>綠色能源科技碩士學位學程<br>106<br>The aluminum-manufacturing industry stands in a pivotal po-sition of heavy metal systems entirely. It not only imparts special heavy metal properties and highly added value to aluminum but also provides a wide range of application and commercial market to aluminum products. Among all of the aluminum manufacturing procedures, including smelting, casting and electroplating, are all depend on the demand of aluminum industry. To date, due to the market demands, lack of natural recourses and awareness of envi-ronmental protection, the research will be focused on waste water treatment and sludge reduction of aluminum-manufacturing indus-try. The study will be divided into three parts. The mainly used is nano-sized coagulant, and the materials are micronized for compar-ison. First of all, the amount of the sludge of traditional lime, calci-um hydroxide, magnesium hydroxide and alkali coagulant will be compared and analysis. According to the result, the amount of the dry sludge provided by traditional lime weight 28 g and has a phosphorus index of 2500 mg/l; on the other hand, calcium hy-droxide shows great performance on wasted produce, it has a weight of the dry sludge of 5.28g and a phosphorus index of 1100 mg/l. Second, the effect of adding different amount of calcium hy-droxide into flocculating agent SC will be investigated. The result shows that there will have a weight of the dry sludge of 2.8g and a phosphorus index of 300 mg/l while adding 3.5 g of calcium hy-droxide and 1.5 g of SC solution into 100 ml of aluminum-manufacturing water waste which is better than the waste-water treatment in general industry. Eventually, according to the result above, a blending ratio of zeolite to SC is 19:1 will be introduced into the waste-water treat-ment to reduce the cost. The result shows the blending prescription greatly reduces sludge yield and the value of phosphorous index. Additionally, the waste-water treatment that going under the blend-ing prescription process will be more effective and reduce the cost of resources.

Environmental pollution from untreated wastewater disposal is one of the most serious environmental issues. Hexavalent chromium, Cr(VI), is known to be a very toxic compound, frequently found in polluted industrial wastewaters, and causes major environmental problems. On the other hand, among the agro-industrial wastewaters, dairy wastewaters can also cause serious environmental pollution due to their high organic loads. Specifically, when untreated dairy wastewater is deposited into surface water bodies it can cause eutrophication and environmental toxicity. The use of constructed wetlands began 40 years ago in North America and Europe. The idea arose from the use of wetlands as final recipients to treat effluent wastewaters. After studies on their construction and improved operations, today constructed wetlands are used as a processing technology in many countries for the treatment of municipal wastewater, industrial wastewater, landfill leachates, etc. Due to their simplicity and low operational cost, constructed wetlands are becoming more prevalent in wastewater treatment all over the world. Their range of applications is no longer limited to municipal wastewater or industrial wastewater but has expanded to the treatment of heavily polluted wastewaters such as agro-industrial effluents. Constructed wetlands can tolerate high pollutant loads and toxic substances without reducing their removal ability, thus these systems are very effective bio-reactors even in hostile environments. The potential application of constructed wetlands in the treatment of chromium-bearing wastewaters has been reported recently. Additionally, secondary cheese whey, a nutrient-rich wastewater which has high potential of polluting surface and/or groundwater, is now being treated either by conventional or biological treatment processes. However, limited research has been conducted on the treatment of secondary cheese whey using constructed wetlands. The objectives of this PhD research were to evaluate a) the effect of different parameters (HRT, temperature, physiochemical parameters) on the treatment of wastewater containing Cr(VI) and secondary cheese whey, using pilot-scale horizontal subsurface flow (HSF) constructed wetlands, b) a sustainable disposal technique of chromium treated reed biomass and c) the treatment efficiency of undiluted secondary cheese whey using pilot-scale HSF constructed wetland at very low HRT and removal of Cr(VI) by providing cheese whey as source of carbon. In the 1st experimental period of this dissertation, the research focused on the study of integrated chromium removal from aqueous solutions in HSF constructed wetlands. Two pilot-scale HSF constructed wetlands (CWs) units were built and operated. One unit was planted with common reeds (Phragmites australis) and one was kept unplanted. Influent concentrations of Cr(VI) ranged from 0.5 to 10 mg/L. The effects of temperature and hydraulic residence time (8 - 0.5 days) on Cr(VI) removal were studied. Temperature proved to affect Cr(VI) removal in both units. In the planted unit, maximum Cr(VI) removal efficiencies of 100% were recorded at HRT’s of 1 day with Cr(VI) concentrations of 5, 2.5 and 1 mg/L, while a significantly lower removal rate was recorded in the unplanted unit. Harvested reed biomass from the CWs was co-composted with olive mill wastes. The final product had excellent physicochemical characteristics (C/N: 14.1-14.7, germination index (GI): 145-157%, Cr: 8-10 mg/kg dry mass), fulfills EU requirements, and can be used as a fertilizer in organic farming. In the 2nd experiment of the first experimental period of this research, two horizontal subsurface flow pilot-scale constructed wetlands were built and operated for almost two years to treat secondary cheese whey. One unit was planted with common reeds (Phragmites australis) and one was kept unplanted. The pilot-scale wetlands operated under various hydraulic residence times (8, 4, 2 and 1 day), temperatures (2.4 to 32.90C) and COD influent concentrations (1200 to 7200 mg/L) in order to examine their effect on secondary cheese whey treatment efficiency. Both units successfully removed organic matter, as COD removal efficiencies of 91% and 77.23% were recorded for the planted and unplanted unit, respectively. Hydraulic residence time affected COD removal efficiency only when limited to 1 day. Temperature significantly affected COD removal only in the unplanted unit, while the planted unit's efficiency was affected only by the annual plant growth cycle. It should be noted that COD effluent concentrations were below EU legislation units (120 mg/L) even when the CWs operated under the shortest hydraulic residence time ever reported in the literature (2 days) with COD influent concentrations ranging from 1200 to 3500 mg/L. In the 2rd experimental period, a mixed solution of cheese whey and hexavalent chromium was treated using pilot-scale horizontal subsurface flow constructed wetlands. This study was performed in order to assess the effect of hydraulic residence time, the initial concentrations of both substances (i.e., Cr(VI) and cheese whey), the presence of vegetation, and surface load throughout the treatment process. Two hydraulic residence times (HRT) (8 and 4 days) were applied. The average electrical conductivity did not show any significance and the average pH values also did not fluctuate. COD concentrations varied between 2000 to 3000 mg/L, and Cr(VI) concentrations were between 0.5 and 5 mg/L. Regarding the removal of organic matter, the planted pilot units had the highest removal rates of around 70%, compared to the unplanted units with around 50%. The vegetation does not affect the removal of Cr(VI) whereas for COD removal, the vegetation does not perform its proper function which leads us to conclude that Cr(VI) influences the removal of COD. The overall outcome of this research is a significant contribution to the treatment of Cr(VI) and secondary cheese whey using constructed wetland technology. It could also be concluded that, constructed wetlands can potentially remove both Cr(VI) and COD at very low HRTs (1 and 2 days, respectively), when receiving moderate pollutant concentrations (5 mg Cr(VI)/L and >5000 mg COD/L), without any seasonal effect. Moreover, by using cheese whey as the carbon source, Cr(VI) can be successfully removed in constructed wetland systems with 4 days of HRT.<br>Η ρύπανση του περιβάλλοντος από τα ανεπεξέργαστα λύματα αποτελεί ένα από τα σημαντικότερα περιβαλλοντικά ζητήματα. Το εξασθενές χρώμιο (Cr(VI)), που είναι γνωστό για την τοξική του δράση, εντοπίζεται συχνά σε βιομηχανικά υγρά απόβλητα και προκαλεί σημαντικά περιβαλλοντικά προβλήματα. Από την άλλη τα υγρά απόβλητα τυροκομικών μονάδων επίσης αποτελούν σημαντική περιβαλλοντική απειλή, λόγω του υψηλού οργανικού τους φορτίου. Ειδικότερα όταν ανεπεξέργαστα τυροκομικά υγρά απόβλητα καταλήγουν σε επιφανειακά υδάτινα σώματα μπορούν να προκαλέσουν ευτροφισμό και τοξικά φαινόμενα. Η χρήση των τεχνητών υγροβιότοπων ξεκίνησε πριν από περίπου 40 χρόνια στη Βόρεια Αμερική και την Ευρώπη. Η ιδέα προήλθε από τη χρήση φυσικών υγροβιότοπων ως τελικών αποδεκτών επεξεργασμένων υγρών αποβλήτων. Μετά από εκτεταμένη έρευνα σήμερα οι τεχνητοί υγροβιότοποι χρησιμοποιούνται ευρέως ως τεχνολογία επεξεργασίας διαφόρων ειδών υγρών αποβλήτων και απορροών (π.χ. αστικά, βιομηχανικά, δισταλλάγματα κλπ.). Λόγω της απλότητας τους και του χαμηλού λειτουργικού κόστους οι τεχνητοί υγροβιότοποι αποτελούν πλέον μια ανταγωνιστική τεχνολογία. Το εύρος των εφαρμογών τους δεν περιορίζεται πλέον μόνο στην επεξεργασία αστικών υγρών αποβλήτων, αλλά έχει επεκταθεί και στην επεξεργασία ισχυρών υγρών αποβλήτων, όπως των αγροτοβιομηχανικών. Οι τεχνητοί υγροβιότοποι είναι ανθεκτικοί σε υψηλά ρυπαντικά φορτία και σε τοξικές ουσίες χωρίς να επηρεάζεται σημαντικά η λειτουργία τους. Συνεπώς οι τεχνητοί υγροβιότοποι είναι ιδιαιτέρως αποτελεσματικοί βίο-αντιδραστήρες ακόμα και ιδιαίτερα εχθρικά περιβάλλοντα. Η δυνατότητα χρήσης τεχνητών υγροβιότοπων για την επεξεργασία υγρών αποβλήτων με χρώμιο, μόλις πρόσφατα έχει αρχίσει να μελετάται. Επί πλέον ο δευτερογενής ορρός γάλακτος (τυρόγαλα), που είναι ένα υγρό απόβλητο με υψηλό περιεχόμενο θρεπτικών, κυρίως επεξεργάζεται με τη χρήση φυσικοχημικών και βιολογικών μεθόδων, ενώ η χρήση τεχνητών υγροβιότοπων είναι περιορισμένη. Ο κύριος σκοπός της παρούσας διατριβής ήταν η αξιολόγηση της επίδρασης διαφόρων παραμέτρων (υδραυλικού χρόνου παραμονής-HRT, θερμοκρασίας, φυσικοχημικών παραμέτρων) στην επεξεργασία αποβλήτων που περιέχουν Cr(VI) καθώς και του δευτερογενούς ορρού γάλακτος με τη χρήση πιλοτικών μονάδων τεχνητών υγροβιότοπων οριζόντιας υπόγειας ροής. Επιπλέον η παρούσα διατριβή στόχευε και στην εξεύρεση μιας βιώσιμης τεχνικής για την επεξεργασία της φυτικής βιομάζας και στην χρήση του δευτερογενούς ορρού γάλακτος, ως πηγή άνθρακα στην επεξεργασία του Cr(VI). Στη διάρκεια της 1ης πειραματικής περιόδου της παρούσας διατριβής, η έρευνα επικεντρώθηκε στη μελέτη της ολοκληρωμένης απομάκρυνσης του χρωμίου από υδατικά διαλύματα και στην επεξεργασία δευτερογενή ορρού γάλακτος από πιλοτικές μονάδες τεχνητών υγροβιότοπων οριζόντιας υπόγειας ροής. Για την ολοκληρωμένη απομάκρυνση του Cr(VI) χρησιμοποιηθήκαν δύο πιλοτικές μονάδες τεχνητών υγροβιότοπων οριζόντιας υπόγειας ροής. Η μία πιλοτική μονάδα ήταν φυτεμένη με κοινό καλάμι (Phragmites australis), ενώ η άλλη παρέμεινε αφύτευτη. Οι συγκεντρώσεις του Cr(VI) στα υδατικά διαλύματα κυμάνθηκαν από 0.5 έως 10 mg/L. Επίσης εξετάστηκε η επίδραση της θερμοκρασίας και του HRT (8 - 0.5 ημέρες) στην αφαίρεση του Cr(VI). Η θερμοκρασία αποδείχτηκε να επηρεάζει την αφαίρεση του Cr(VI) και στις 2 πιλοτικές μονάδες. Οι αποδόσεις απομάκρυνσης του Cr(VI) στην φυτεμένη πιλοτική μονάδα έφθασαν το 100% ακόμα και για HRT της 1 ημέρας, με συγκεντρώσεις εισόδου Cr(VI) 5, 2.5 και 1 mg/L. Σε αντίθεση, η αφύτευτη πιλοτική μονάδα κατέγραψε σημαντικά χαμηλότερες αποδόσεις απομάκρυνσης Cr(VI). Η φυτική βιομάζα που συλλέχθηκε από την φυτεμένη πιλοτική μονάδα κομποστοποιήθηκε μαζί με στερεά απόβλητα ελαιοτριβείου. Το τελικό προϊόν της κομποστοποιήσης είχε εξαιρετικά φυσικοχημικά χαρακτηριστικά (C/N: 14.1-14.7, δείκτης βλαστικότητας (GI): 145-157%, Cr: 8-10 mg/kg dry mass), τα οποία πληρούν τα όρια της Ευρωπαϊκής Ένωσης για τη χρήση του ως λίπασμα σε οργανικές καλλιέργειες. Η δεύτερη πειραματική διάταξη της 1ης πειραματικής περιόδου περιελάμβανε δύο όμοιες πιλοτικές μονάδες με τις παραπάνω, που ωστόσο χρησιμοποιήθηκαν για την επεξεργασία δευτερογενούς ορρού τυρογάλακτος. Οι πιλοτικές μονάδες λειτούργησαν υπό διαφόρους χρόνους παραμονής (8, 4, 2 και 1 ημέρα), θερμοκρασίες (από 2.4 έως 32.90C) και συγκεντρώσεις εισόδου COD (από 1200 έως 7200 mg/L) Οι δύο μονάδες επεξεργάστηκαν επιτυχώς το δευτερογενή ορρό γάλακτος, αφού καταγράφηκαν για την φυτεμένη και την αφύτευτη πιλοτική μονάδα, αποδόσεις αφαίρεσης COD της τάξης του 91% και 77.23%, αντίστοιχα. Ο υδραυλικός χρόνος παραμονής επηρέασε την απόδοση τω δύο πιλοτικών μονάδων μόνο όταν μειώθηκε στην 1 ημέρα. Αντιθέτως, η θερμοκρασία επηρέασε μόνο την αφύτευτη πιλοτική μονάδα, ενώ η απόδοση της φυτεμένης επηρεάστηκε μόνο από τον ετήσιο κύκλο ανάπτυξης των φυτών. Πρέπει να τονιστεί ότι οι συγκεντρώσεις εξόδου του COD ήταν χαμηλότερες των ορίων της Ε.Ε., ακόμα και για χρόνους παραμονής 2 ημερών (ο χαμηλότερος που έχει αναφερθεί μέχρι τώρα στη βιβλιογραφία) με αρχικές συγκεντρώσεις εισόδου COD από 1200 έως 3500 mg/L. Στη διάρκεια της 2ης πειραματικής περιόδου οι τέσσερεις συνολικά πιλοτικές μονάδες που χρησιμοποιήθηκαν στην 1η περίοδο, χρησιμοποιήθηκαν επίσης και για την επεξεργασία ενός μεικτού διαλύματος δευτερογενή ορρού γάλακτος και Cr(VI). Στόχος των πειραμάτων που πραγματοποιήθηκαν ήταν η αξιολόγηση της επίδρασης του χρόνου παραμονής (8 και 4 ημέρες), των συγκεντρώσεων εισόδου του Cr(VI) (από 0.5 έως 5 mg/L) και του COD (από 2000 έως 3000 mg/L), του φυτού και του επιφανειακού φορτίου στην απόδοση των πιλοτικών μονάδων. Όσον αφόρα την αφαίρεση της οργανικής ύλης, οι φυτεμένες πιλοτικές μονάδες κατέγραψαν υψηλότερα ποσοστά απομάκρυνσης (περίπου 70%) σε σύγκριση με τις αφύτευτες (περίπου 50%). Σε αντίθεση, η απομάκρυνση του Cr(VI) έδειξε να μην επηρεάζεται από την παρουσία φυτών. Τέλος, παρατηρήθηκε ότι η ύπαρξη του Cr(VI) επηρεάζει την απομάκρυνση του οργανικού φορτίου. Τα τελικά συμπεράσματα της παρούσας διατριβής αποτελούν μια σημαντική συνεισφορά στην επεξεργασία υγρών αποβλήτων που περιέχουν Cr(VI) καθώς και του δευτερογενή ορρού γάλακτος από τεχνητούς υγροβιότοπους. Επίσης μπορεί να συμπεραθεί ότι η χρήση των τεχνητών υγροβιότοπων για την αφαίρεση Cr(VI) και COD μπορεί να επιτευχθεί ακόμη και σε πολύ χαμηλούς χρόνους παραμονής (1 και 2 ημερών, αντίστοιχα), καθώς και σε υψηλές αρχικές συγκεντρώσεις (5 mg Cr(VI)/L και >5000 mg COD/L, αντίστοιχα). Τέλος, η χρήση του δευτερογενή ορρού γάλακτος ως πηγή άνθρακα στην αφαίρεση του Cr(VI), ήταν πλήρως επιτυχημένη.

碩士<br>高雄醫學院<br>藥學研究所<br>86<br>The purpose of this study was to establish an analytical methods of hexavalent chromium, total chromium, lead, cadmium, copper, nickel and manganese in the wastewater discharged from leather production . The tannery manufactory is located on the industrial park of Ping -Tong City Country and with wastewater treatment facilities.These wastewater samples are treated, respectively, and the analytical techniques were as follow : The Cr (VI) concentration determined by 1,5-Diphenylcarbazide (DPC) Colorimetry and discussion about the amount of DPC addition affects absorption signal. The total chromium, lead, cadmium, copper, nickel and manganese were determined by graphite furnace atomic absorption sprctrophotometry, and discussion about that effects of ashing, atomization temperatures and gas flow on absorbance signal. The validation oThe results showed that the function of wastewater treatment facilities of this tannery can reduce concentrations of metals in wastewater obviously, and in effluent waters besides cadmium metal , the quantity contained of other metals are conformed to the effluent standards . But, in order to avoid causing environment pollution, this tannery shall improve further.

碩士<br>國立中興大學<br>環境工程學系所<br>100<br>Molybdenum presented in the raw wastewater was due to the production and processes using phosphate acid containing Mo and due to the utilization of sodium molybdate, especially in the high-tech industrial in the Science Park. This study employed two different commercially available ion exchange (IX) resins to evaluate the removal efficiency of Mo from industrial wastewater. The experimental results indicated that the adsorption capacities of resins A and B were 3.9 and 32 mg-Mo/100 mL-IX, respectively. The regeneration efficiencies of resins A and B were 34% and 90%, respectively. After the regeneration, the regenerated solutions were also used to recovery Mo using the precipitation process. The optimum operating conditions were as following：pH at 1.3±0.5, temperature at 80℃, the ratio of Mo and deionized water at 1：4, and the operating time of 10 min. The recovered materials contained Mo at 32%. The secondary refined conditions were the operating time of 3 hours at 400℃. After the secondary refined operation, about 99% purity of oxide Mo could be reached.

碩士<br>朝陽科技大學<br>環境工程與管理系碩士班<br>91<br>Abstract In Taiwan, industrial parks are major sources of water pollution. Inefficient operation of WWT often leads to improper discharge causing pollution of violating the percent standard. Continuous improvement in wastewater discharge management is the main objective of the Taiwanese government today. This research proposes a learning system that can be adopted by wastewater treatment plants to train its management staff, discover existing problems, and improve its wastewater treatment operation. The learning system is a benchmark used widely in management science. This study provides a learning model for wastewater treatment plants. Management staffs of a WWT the system can use this model to set improvement objectives, diagnose various problems within the plant, distinguish model employees from the rest, and improve the efficiency of the treatment plant. This study employed the following analysis: *Data envelopment analysis (DEA) to plants as appraise the study plant in terms of operation efficiency differentiate the efficiencies of various management styles. *System simulation analysis to predict the resulting savings by eliminating ?. DEA provides estimates of the efficiency of wastewater treatment plants. The results serve as a benchmarking to help managers understand the input-output relationships. Results also point out weaknesses in the management and highlight possibility of improvement. DEA provides a reference standard to quantify the operational efficiency and improvement of treatment plants. System simulation is conducted with the BioWin32 simulator. This simulator provides a simulated view of how a plant functions. There is very minor difference in the simulated and the actual results. Simulation analysis is to discover crucial operating parameters of each unit operation. Adjustment in input-output and operating parameters will help to improve wastewater treatment. This paper provides a case study on the Lion Pup wastewater treatment plant in Taichung. After a year of practical study and promotion, we found that the continuous cycle of weakness analysis and improvement are crucial for the successful operation and management of a treatment plant. Major findings of this research include: 1. High concentration of wastewater inflow was frequent occurrence and decreased the biological treatment efficiency significantly. 2. The use of equalization tank could reduce wastewater concentration, stabilize the efficiency of secondary treatment unit and decrease the amount of coagulants usage.　 3. After the improvement action, the running efficiency analyzed by DEA enhanced from 0.42 to 0.64. The COD value of discharge were decreased from 94 to 60 mg/L, SS were decreased from 68 to 38 mg/L, and the total treatment cost droped from 9.0 to 7.7 NT dollar/m3. According to the benchmark procedure, the treatment function and efficiency of the wastewater treatment plant could be improved continuously.

碩士<br>朝陽科技大學<br>環境工程與管理系碩士班<br>98<br>This paper aims to investigate the chemical analysis and Microtox test of industrial zone and scientific industrial park wastewater. Results showed that both wastewater analyses met the effluent standard. In addition, both Microtox test showed insignificant toxicological results. It was also noted that influent of scientific industrial park wastewater showed relatively higher EC50 or EC20. It was evident that biological treatment system had the potential to remove pollutants leading to a relative lower Microtox results. Chemical analysis and Microtox test could provide the information of operational performances for industrial zone and scientific industrial park wastewater treatment.

碩士<br>國立中央大學<br>環境工程研究所碩士在職專班<br>93<br>Among the various functional deficiencies of wastewater treatment plants, the hardware facilities failure and their improper operations and maintenance are the two major factors. In order to provide a reference for facilities expansion or improvement and to perform excellent operating efficiency of wastewater treatment plants, this study investigated the designed functions and process operating conditions for the case plant by applying CPE (Comprehensive Performance Evaluation) method with performance evaluation of treatment processes. The results demonstrated that due to lost orders of factories, impact of economic recession, and wastewater recycling, the influent of the plant was gradual decrease. Also, the textile wastewater occupied higher percentage of influent wastewater from factories in industrial parks, resulting in the non-biodegradable and high-colored wastewater characteristics. Based on the results of CPE, the performance of wastewater treatment process was normal and only the improvement of non-structural changes are required to improve functions for some treatment units. However, the performance of sludge treatment process was poor and the related units must have structural changes to be improved. Compared actual operating parameters with designed ones of treatment units, it was suggested to adjust the influent quantities of aerated grit chamber or increase the aeration to reduce the settling of organic solids on the bottom of chamber. On the other hand, the clarifiers had extra capacity due to the over-designed parameters, it was then suggested to change the number of clarifier worked in turns to save the cost of electricity and to reduce the consumption of equipments. With other benefits of improvement, when adopting proper parameters in this plant, the electricity cost could save 0.4 kW-h per ton of wastewater and the sludge production would be reduced at 0.07 kg per ton of wastewater.

碩士<br>國立中央大學<br>環境工程研究所碩士在職專班<br>98<br>To ensure break-even of wasterwater treatment plants, the pricing for wastewater treatment at industrial parks should base upon the principles of user pays, fairness, and reasonability. Current flat rate tariffs fail to consider inter-industry differences in types of contamination, quantity, and quality. Because different types of contamination of wastewater require a variety of treatments to remove the contamination, cost of treatment varies considerably across industries. The flat-rate tariffs result in overcharge for some industries and undercharge for others, which contradicts the user pays principle and leads to operating losses of the wastewater treatment plants at industrial parks. In this paper, I examine treatment wastewater treatment costs for eight industries. Using both archival and survey data, I compare the quantity, quality, and costs of two disposal methods for each of the eight industries and propose a break-even pricing formula. The two methods examined are: self-discharge by individual business outside the industrial park and central disposal by an industrial park agency. Under the assumption of break even, I develop the pricing formula after considering the different treatment costs of the two methods examined. Using the said formula, I further analyze the variance of treatment costs across different industries, illustrating the unfairness and unreasonableness of current single-rate tariffs. To minimize impact on other industries beyond the scope of this study, the proposed pricing formula is derived while holding constant the total revenues of the wastewater treatment plant. The pricing formula produces one rate adjustment, denoted in percentage as x, for each industry, thereby arriving at differential, industry-specific rates. Results of this study provide a basis for future pricing revisions.

碩士<br>雲林科技大學<br>化學工程與材料工程研究所<br>96<br>The aim of this thesis is to investigate adsorption and electrosorption of copper ion from wastewater on variously activated carbon fibers (ACFs) cloths. The commercial polyacrylonitrile-based ACFs cloth was modified by nitric acid or impregnated by chitosan solution. Adsorption/electrosorption capacities of copper ions were also studied as dilute complexing agents, such as EDTA and sodium citrate, existed in wastewater. The modified ACFs cloths were characterized using nitrogen adsorption, FTIR, and cyclic voltammetry. A static state adsorption system was designed to measure adsorption/electrosorption capacity of copper ion on the ACFs cloth. The adsorption/electrosorption capacity of ACFs cloth with different bias potentials were measured, and the electrosorption isotherms were also investigated. Experimental results showed that surface functional groups of ACFs cloth was one of key factors on adsorption efficiency. Activated carbon cloth modified by chitosan enhanced adsorption/electrosorption efficiency. The cause was attributed that the ACFs cloth modified by chitosan contained amino groups for chelating copper ions. In addition, adsorption/electrosorption capacity of copper ion on ACFs increased as dilute complexing agent existed in wastewater. Experimental results also revealed that electrosorption can effectively increase the adsorption capacity. The adsorption/electrosorption of copper ion on carbon cloth followed Langmuir isotherms. The equilibrium adsorption capacity at 0.3 V was 24.74 mg/g, which was nearly two times higher than that at open circuit.

碩士<br>國立臺北大學<br>資源管理研究所碩士在職專班<br>92<br>Several researchers estimated that the amount of water supply will be less than that of water demand in Taiwan in 2006 and water shortage will become a serious problem thereafter. To overcome this problem, several water saving strategies are applied in industries. Among these are more concentrated cooling water usage, boiler water reclamation, condensed water collection, reclamation and reuse of slightly-contaminated water and water reclamation via RO system, etc. Although many approaches have been used to increase water usage efficiency, only a tiny fraction of the final effluent from industry after water treatment is reclaimed through RO system. With the great advance in technology, the feasibility of wastewater reclamation can be boosted profoundly by combining wastewater source control, tertiary treatment technologies and engineering practices. In this study, the strategies of industrial wastewater reclamation are investigated in accordance with current water usage in different industries. In addition, the feasibility of industrial wastewater reclamation and reuse are analyzed from technology, economy and policy aspects. The required quality of recycling water depends on where it is used, and the required water quality determines the cost-effective technology that can be applied to reclaim wastewater. Apart from choosing a suitable method, the determination of the wastewater reclamation point and recycling water application point always exert great influence on the reclamation cost. By analyzing a few wastewater reclamation cases implemented in Taiwan and other countries, several conclusions were obtained. The results show that the wastewater reclamation is feasible with several prerequisites. First, government has to clearly set up the wastewater reclamation rate for each year and stipulates the relevant regulations. Second, some incentives, such as tax exempt, different effluent discharge fee and investment subvention, should be offered to the manufacturer by the government. Therefore, to suppress the impact of the intractable water shortage problem to industrial development, government should establish the industrial water usage policy and relevant schemes as soon as possible. The wastewater discharge fee and industrial water usage charge can be designed to increase incentives for wastewater reclamation, e.g., reductions in water pollution fee, wastewater treatment charge, can be properly adjusted. Meanwhile, the administrative agency for industrial water usage should set up the goal of wastewater reclamation and the time schedule to attain this goal. Industrial park management regulations and factory management guidance should be used to achieve the yearly targeted water reuse rate, water recycling rate and total water recycling rate so that the set goal of 90% total recycling rate in 2011 can be fulfilled, and thus eliminate the industrial water shortage problem .

碩士<br>國立中興大學<br>化學工程學系<br>90<br>Immobilized HRP was developed to remove the 4-chlorophenol from industry wastewater. The optimal conditions for immobilization and for enzyme activity were determined. Porous aminopropyl glass bead (APG) was selected as the support for the covalent bonding of HRP. The optimal conditions were determined as: conjugation with 2.5% glutaraldehyde at 25℃ for 8 hours followed by 2.5mg immobilization with HRP/mL at 4℃ for 12 hours. The optimal reaction pH for the immobilized HRP ranged from 7~9, one unit pH wider than the free HRP. The optimal reaction temperature was raised to 70℃. The thermo stability (50~80℃) of the immobilized HRP was also improved significantly. The removal efficiency of 4-chlorophenol from waste water by immobilized HRP was also investigated in our research. The optimal 4-chlorophenol removal efficiency was observed at pH 7.5. The results represented that at low concentration of HRP, the removal efficiency of 4-chlorophenol was increased, about 2.7 fold by the addition of PEG. Meanwhile, the removal efficiency of 4-chlorophenol was also enhanced by the inclusion of PEG in the muti-cycle operation. This study has successfully demonstrated that combining immobilization of HRP and PEG addition can increase operation stability.

碩士<br>國立成功大學<br>水利及海洋工程學系專班<br>100<br>In this paper, the TFT-LCD plant located in the Tainan Science Park was taken as a typical example to investigation the effect of waste water discharged into river or coastal waters . Field data obserred from Yanshui river and its entuary using monitoring probes were used for the analysis of BOD contains. The data anarysis shows that daily discharge of waste water from the TFT-LCD plant is large and processes a higher value of BOD. To reduce the BOD value, the present study presents an alternate to discharge the waste water into the coastal waters through the diffussion of tidal and nearshore current. The major reason is whenthe river has been seriously polluted, it is difficult to remove impurities and thus clean itself. The observations from the estuary of Yanshui river show that BOD valued can be dropped down to 98%. It is concluded that waster discharged to coaster water is a feasible way to reduce BOD value by dilution process with the help of tide and nearshore current and waster of the open sea. Keywords: TFT-LCD waste water, river, coastal water, BOD

碩士<br>國立中央大學<br>環境工程研究所碩士在職專班<br>97<br>Abstract Since the technology of product process continuously is improved some of the specific pollutants potentially cause serious problems on operation and treatment of the wastewater treatment plant in the industrial parks. Further, these pollutants could increase the cost of operation and maintainance for the wastewater treatment plant. Thus, it is important to set up reasonable fee criteria for these specific wastewaters. The purpose of this study is to evaluate the effects of chemical mechanical planarization (CMP) wastewater on the removal efficiency of chemical treatment process in a wastewater treatment plant. Moreover, characteristics of the wastewater including high turbidity, low suspended solid (SS) and micro-size particles, which result in interference on the floc formation in the coagulation process, are also investigated. The results indicated pH value of the wastewater reaches limit level that generated the highest effect on the floc formation. It is suggested that the optimum coagulant (aluminum sulfate, Al2(SO4)3) dose is 350 ppm when the pH level is adjusted to 10. However, without the CMP wastewater, the optimum coagulant dose for the general wastewater decreases to 50 ppm. The optimum dose for the simulated synthetic water is 100 ppm. When the raw wastewater mixed with the CMP wastewater was filtrated using the 0.45μm and 0.2μm filters, the optimum dose of the mixed wastewater is 50 ppm that is equal to general wastewater. Moreover, if the wastewaters were classified based on the pollution sources, the added amount of aluminum sulfate in CMP wastewater is two times than that of in general water with the similar coagulation efficiency. The fee criteria about wastewater discharged into wastewater treatment system in the industrial park is performed based on the concentration of SS through 1μm filter. In this case, the measured SS concentration cannot reflect on the pollution level for the CMP wastewater because some of the SS in the CMP wastewater can penetrate the 1μm filter. We suggested that the 0.45μm filter is used to measure SS concentration of the CMP wastewater which is a proper way for the cost assessment. Moreover, the increase in the fee according to the SS concentration is approximate 40%, which reduce the loading of operation cost.

Advanced wastewater treatment techniques, such as adsorption, are economically and environmentally essential in the removal of non-biodegradable toxic compounds from industrial wastewater. The present study focuses on the use of low cost adsorbents prepared from pine sawdust, coal fly ash and sugarcane bagasse to adsorb recalcitrant compounds such as heavy metals, phenol and direct dyes from synthetic wastewater. Carbonization of the adsorbents was done using a muffle furnace whereas a fluidized bed reactor was used to prepare steam activated sawdust. Both batch and column tests were performed to investigate the use of these alternative adsorbents as potential replacements for the current costly commercial adsorbents. A 23 full-factorial design with four centre points and response surface methodology were used to study the interactive effect of the operating conditions on the adsorption capacity of sawdust and coal fly ash. In addition, the performance of the low cost adsorbents was compared with that of commercial activated carbon (CAC). The maximum adsorption capacities were determined and correlated with the physicochemical properties of the adsorbents. Adsorption capacity was found to vary with initial concentration, adsorbent dose and pH. An increase in pH led to a significant increase in heavy metal removal suggesting the involvement of ion exchange mechanism. In column studies, breakthrough times increased with an increase in bed height and aspect ratio. Conversely, breakthrough times decreased with an increase in initial concentration. Overall, commercial activated carbon was found to be superior; however, sawdust and coal fly ash showed potential as alternative adsorbents for the removal of heavy metals and phenol from petrochemical wastewater. Additionally, the trend followed by the maximum monolayer adsorption capacities, qmax for the four adsorbents used to treat petrochemical wastewater was in agreement with the specific surface area of the adsorbents i.e adsorbents with high specific surface area had high qmax values with a few exceptions. Amongst the low cost adsorbent, steam activated sawdust (SAS) was superior and coal fly ash had the lowest adsorption capacities. Also, the highest adsorbed contaminant by steam activated sawdust was Fe (15.385 mg/g). It has been shown that the performance of steam activated sawdust was comparable to that of commercial activated carbon in the removal of Pb and Ni. Nevertheless, sugarcane bagasse proved to be a better adsorbent than coal fly ash in the uptake of direct red dyes from textile wastewater. Direct red 80 (DR 80) was the highest adsorbed dye by both sugarcane bagasse (6.536 mg/g) and coal fly ash (1.560 mg/g). Equilibrium data for metal removal conformed well to the Freundlich isotherm whereas phenol and direct dye removal complied with the Langmuir adsorption isotherm model. Kinetic data were fitted to Lagergren first-order, pseudo secondorder and the intraparticle diffusion models. Thus, kinetic parameters, rate constants, equilibrium adsorption capacities and related correlation coefficients, for each kinetic model were calculated and discussed. Consequently, the adsorption of cobalt followed pseudo second order kinetics suggesting chemisorption for all the tested adsorbents. Also, results suggested that intraparticle diffusion was not the only step controlling the overall adsorption process of cobalt. Results presented here can help to design an appropriate environmental management strategy to minimize the adverse impacts caused by industrial wastewater.