Дисертації з теми "Industrial water supply Victoria"

Water supply system planning is concerned about the design of water supply infrastructure for distributing water from sources to users. Population growth, economic development and diminishing freshwater supplies are posing growing challenges for water supply system planning in many urban areas. Besides the need to exploit alternative water sources to the conventional surface and groundwater supplies, such as reclaimed water, a systematic point of view has to be taken for the efficient management of all potential water resources, so that issues of water supply, storage, treatment and reuse are not considered separately, but rather in the context of their interactions. The focus of this dissertation is to develop mathematical models and optimization algorithms for water supply system planning, where the interaction of different system components is explicitly considered. A deterministic nonlinear programming model is proposed at first to decide pipe and pump sizes in a regional water supply system for satisfying given potable and non-potable user demands over a certain planning horizon. A branch-and-bound algorithm based on the reformulation-linearization technique is then developed for solving the model to global optimality. To handle uncertainty in the planning process, a stochastic programming (SP) model and a robust optimization (RO) model are successively proposed to deal with random water supply and demand and the risk of facility failure, respectively. Both models attempt to make the decision of building some additional treatment and recharge facilities for recycling wastewater on-the-site. While the objective of the SP model is to minimize the total system design and expected operation cost, the RO model tries to achieve a favorable trade-off between system cost and system robustness, where the system robustness is defined in terms of meeting given user demands against the worst-case failure mode. The Benders decomposition method is then applied for solving both models by exploiting their special structure.

Nesta tese, é apresentada uma revisão bibliográfica de reuso potável indireto e reuso industrial. Examina-se na prática dois estudos de caso, um de reuso industrial e um de reuso potável com aplicação para a Baixada Santista. O de reuso industrial refere-se ao projeto de fornecidmento de água oriunda da represa Billings, que com pequeno tratamento é oferecida às indústrias de Cubatão para fins não nobres como por exemplo, refrigeração, aquecimento a vapor, rega de jardins, abatimento de material particulado. etc. Quanto ao de reuso potável a apresentação se faz através de experimentos de laboratórios, examinando-se trihalometanos (THM) e o poder desinfetante de alguns produtos químicos após passagem da água por carvão ativado granular e outros tratamentos, e suas consequências na rede de abastecimento de água. Concluiu-se que o melhor ponto de instalação da captação para o abastecimento de água industrial fica entre os canais de fuga da usina Henry Borden, em Cubatão, por seu melhor desempenho econômico e pela possibilidade de atendimento no futuro a outras indústrias. Ainda, se comprovou a eficiência do carvão ativado granular na remoção dos precursores de THM e o baixo poder desinfetante da cloramina.
There is in this thesis, a small literature revision about the matter, mainly about indirect potable reuse and industrial reuse. In the practical part they are examined in two cases, industrial reuse and potable reuse, both for the Santos Basin. In the Industrial Reuse, there is a project to distribute industrial water to Cubatão industries, using water from Billings after a small treatment. This water is to be used in refrigeration of steel or to boil water to obtain steam or put in solid material to avoid air pollution, etc. In Potable Reuse, there are many laboratory experiences about THM and desinfection by many chemical products and their consequences in distribuition of water. In conclusion, the best place for ínstalation of the collection of water is located between the Henry Borden Power Plant Channels, in Cubatão, for it\'s superior economic performance and for the possibility to support other industries in the future. It has already confirmed the efficiency of the granular activated carbon to remove THM precursors and its inability to desinfect ammonia chlorine.

A certain amount of water is required for a mine site located in Turgutlu in Western Turkey to be used in mining processes. The purpose of this study is to assess the impacts associated with meeting water supply requirements for the mine. Scope of the study involves determination of the alternative water resources, the assessment of impacts associated with each resource and the selection of the most feasible alternative in the aspect of environmental and technical effects. Three alternatives suggested to supply mine process water are surface water, groundwater and reuse of waste water of Turgutlu town after treatment. A low flow analysis of Gediz River was conducted for the evaluation of the surface water. For the groundwater alternative, Turgutlu-Salihli aquifer model was established using MODFLOW 2009.1 software and the impacts on groundwater resources were evaluated. The evaluation of the last alternative, reuse of waste water of Turgutlu after treatment, was based upon the amount of waste water generated and treatment needed. Results of the alternatives show that each alternative is applicable to supply the required water to the mine site. However, the storage of the Gediz River water in a v small dam in wet seasons to be used later in dry seasons and the reuse of waste water of Turgutlu after treatment are the alternatives with least impacts on existing water users and related ecosystems.

Performance monitoring is commonly portrayed as providing a uniquely objective, rational foundation for decisions, based on a single-stranded feedback loop between setting objectives and measuring results. In this thesis, I investigate whether this portrayal is accurate. I analyse whether the linear model underlying performance monitoring provides an adequate basis for understanding decisions about access to rural water supply in Ethiopia. My examination focuses primarily on the politics of knowledge production from three angles. First, I examine whether the assumptions underlying the definition of ‘access' to rural water used in performance monitoring in Ethiopia, adequately represent the divergent notions of access among the relevant actors. My findings show that formal framings of access, codified in national and international guidelines and benchmarks, focus on technical aspects of the water supply infrastructure. I bring to light that the goal of performance monitoring in relation to achieving ‘access' is driven by the methods used to measure it, mainly the parameters of infrastructure, volume, distance and quality, suggesting a circularity between framings of the inputs to and objectives of appraisal. In this self-referential process, a particular image of the world determines the meaning of performance, which is used as a yardstick. The power of this dynamic is apparent in Ethiopian stakeholders' characterisations of access, which, even when critical, revolve narrowly around these dominant parameters. This one-dimensional and technical framing of access, constantly reproduced in self-referential monitoring circles, contrasts starkly with the multi-dimensional and dynamic nature of the water access experiences of local residents in Ethiopia. Second, I test whether, in reality, monitoring processes conform to the linearity assumed by the feed-back function of performance monitoring. The process tracing method used to illuminate the political and power dynamics of monitoring processes, shows that sector government actors at different administrative levels, with different rationales, provide different stories of ‘access'. Viewed from this perspective, performance monitoring can be seen not, as conventionally asserted, as a uniquely rational appraisal of performance, but rather as being about ‘performing monitoring' – the playing out on a management stage of certain politically-necessary performances. At the same time, I find that numerous less formalised monitoring practices proceed in parallel with the formal PM process, which, together, form a body of largely ‘tacit' knowledge that informs sector stakeholders' daily work. It is this wider body of knowledge, rather than only formalised PM results, that informs decisions. Third, I investigate the mechanisms that led to the formulation of specific decisions associated with rural water access and the role in these of performance monitoring. I find that particular decisions, such as repairs to rural water schemes, have multiple causes, among which performance monitoring is a contributory and necessary, but not sufficient factor. My investigation of criteria affecting budget allocations highlights that sector offices' limited control over them contributes to making strategic planning a rubber stamping exercise whose processes can be characterised as ‘muddling through' as opposed to adhering to the linear model suggested by Results-based Management. My findings highlight the need to break the self-referential cycle of narrowly framed performance monitoring exercises. They suggest greater attention to the ‘tacit' monitoring practices in local settings, and a focus on the process of monitoring and the power relations within it, to complement the dominant focus on monitoring targets and indicators.

Nesta tese, com a metodologia da Arqueologia Industrial, foi analisado o sistema de abastecimento de água na cidade de São Paulo, nos primórdios do século XX, com o excepcional adensamento populacional do pequeno núcleo de estudantes, cujo destino de grande metrópole começava a delinear-se. Com o abandono da solução mais viável, ou seja, o aproveitamento do rio Tietê, que cortava o planalto paulistano, mas que carregava consigo toda sorte de impurezas, a alternativa das autoridades encarregadas do saneamento, foi a introdução de barragens na Serra da Cantareira, com diferentes técnicas construtivas, formando lagos artificiais, cuja forma de armazenamento, águas estagnadas, era motivo de controvérsias entre, engenheiros, médicos e sanitaristas do mundo inteiro. Porém, foi essa a opção escolhida, na tentativa de dessedentar a população paulistana, que enfrentava em 1903, a pior estiagem de toda sua história. Ao contrário dos outros dois reservatórios, Engordador e Guaraú, o do Cabuçu, já possuía ao nascer, os traços da notoriedade que ainda hoje o tornam admirável: a barragem foi projetada com o perfil prático do engenheiro norte-americano Edward Wegmann, revolucionário para a época, e que solucionou o problema do rompimento dos diques de contenção até então comuns, e por ter sido adotado pela primeira vez, no Brasil, o uso do concreto armado nas estruturas, e na construção de sua centenária adutora. Para o tratamento de suas águas, foi empregado de forma pioneira, o hipoclorito de sódio, que viria a eliminar, um grande número de doenças, que tinham na água um nexo causal, e finalmente, ao tornar o abastecimento menos elitizado, quando chegou aos bairros proletários, segregados espacialmente, e que até então, recebiam água em quantidade e qualidade não compatíveis com suas necessidades, transformando suas pobres habitações em moradias sem saúde.
For this thesis we used Industrial Archeology methodology to analyze the water supply system for the city of São Paulo in the early 20th century, a period during which population density was growing rapidly and what had been a small nucleus of students was clearly destined to become a major metropolis. The most obvious solution, using water from the Tietê River that crossed the city, was abandoned as it carried with it all sorts of impurities. The health authorities decided to build damns in the Cantareira Mountains using a variety of building techniques. These damns created large reservoirs and, at the time, the fact that these stored stagnant water was a controversial issue among engineers, physicians and health professionals all over the world. However, this was the option selected to provide the population of the city with water, remembering that in 1903 it was experiencing the worst drought in all its history. Contrary to other reservoirs - Engordador and Guaraú, from the start the Cabuçu Reservoir was known for its structure that, to this day, is admired. This Cabuçu Damn was designed by a practical US engineer by the name of Edward Wegmann. Wegmann's techniques were revolutionary for their time. In order to solve the problem of contention damns that often ruptured, he used reinforced concrete for the first time ever in Brazil. To treat the city's drinking water the authorities decided to use sodium hypochlorite for the first time. This would help eradicate a number of water borne diseases and bring treated waters to the masses. Before this treated water had been a privilege of the elite and the working classes were served with water in a volume and of a quality not compatible with their needs, resulting in households that were not only poor but also unhealthy.

Orientador: Edvar Luvizotto Junior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
Made available in DSpace on 2018-08-19T01:06:39Z (GMT). No. of bitstreams: 1 Spolaor_AntonioSergio_M.pdf: 1467442 bytes, checksum: 3bb14cc0c3edaee265c1b15e36387a66 (MD5) Previous issue date: 2011
Resumo: A automação industrial aplicada em sistemas de abastecimento de água até pouco tempo atrás era bastante simples. Com o advento dos Controladores Programáveis, associado ao desenvolvimento da moderna teoria de controle, permitiu uma automação maior e mais efetiva destes sistemas. Este trabalho discute a utilização da automatização em sistemas de saneamento implementando "inteligência artificial" para tomada de decisão operacional, visando uma melhor distribuição de água entre reservatórios de distribuição. A aplicação dos resultados pode trazer ganhos relacionados ao atendimento das demandas diárias de água do sistema de distribuição. Esta dissertação sob o título de "Automação nos sistemas de abastecimento de água. Caso do controle da reservação de distribuição" foi aplicada em um projeto desenvolvido pela Companhia de Saneamento Básico do Estado de São Paulo - SABESP, na cidade de Santa Rosa de Viterbo, no qual vários conceitos de automação foram utilizados com sucesso. O sistema integrado resultante empregando CLPs e um sistema de controle e aquisição de dados (Supervisory Control and Data Acquisition - SCADA) contribuiu para uma melhoria significativa do sistema de armazenamento e distribuição. A "inteligência artificial" implantada neste trabalho para a tomada de decisão operacional pode ser verificada através dos resultados apresentados
Abstract: Industrial automation systems applied in water supply were quite simple until recently. The advent of Programmable Controllers, associated with the development of modern control theory, allowed a greater and more effective automation of these systems. This paper discusses the use of automation in sanitation systems implementing "artificial intelligence" for operational decision making, seeking a better distribution of water between distribution reservoirs. The application of the results can bring benefits related to meeting the daily demands of water of the distribution system. This dissertation under the title "Automation in water supply systems. Case of the reservation control distribution" was applied in a project developed by Companhia de Saneamento Básico do Estado de São Paulo - SABESP in the city of Santa Rosa de Viterbo, in which various automation concepts have been used successfully. The resulting integrated system using PLCs and a system to control and acquire data (Supervisory Control and Data Acquisition - SCADA) contributed to a significant improvement in the storage and distribution system. The "artificial intelligence" implanted in this work for operational decision making can be verified through the presented results
Mestrado
Saneamento e Ambiente
Mestre em Engenharia Civil

The access of water globally is becoming more strained, why the focus on industrial water use is increasing. The present study examined how industries should approach water efficiency projects, what organizational constraints that should be addressed, and what effects water saving measures have on economic costs, environmental impact and influence from water related risks. The study has been conducted at Saab Group. Primary data for water supply amount and cost has been obtained from twelve sites for the year of 2018. Data from these sites has been used to estimate the water use for the other 43 sites included in this study. Interviews with employees across Saab´s organization and with external stakeholders have functioned as important sources of information, combined with investigations of internal company documents. To facilitate for companies to structurally address water efficiency projects, the concept of the Deming Cycle is developed in this study. The steps included are necessary to address major identified organizational constraints which are lack of communication, lack of incentives for employees, and lack of economic incentives. Furthermore, with water often having energy embedded into it, a new Water Management Hierarchy is developed to include the interrelated aspects of energy supply and energy recovery. The potential for pipe leakages and the challenge to detect these are also identified. If the time from leak occurrence to repair in 2018 was eliminated, the total water supply in Arboga could have been reduced with 10100 m3 which corresponds to 35% of total supply to the site, respectively 35900 m3 and 42% in Björkborn. In Tannefors, water saving measures are identified for a surface treatment process, a facility with testing equipment, and by utilization of groundwater. Not all water saving measures result in reduced annual operating costs, due to an increased energy demand. Furthermore, if neglecting the possibility of energy recovery when aiming for water use reduction, the results show that replacing a once-through cooling system using potable municipal water as a medium with a dry-cooling unit, can increase greenhouse gas emissions. In 2018, the simultaneously implementable water saving measures in Tannefors would have reduced the water supply with 40600 m3, which corresponds to 22% of the total supply to the site. The greenhouse gas emissions would simultaneously have been reduced with 0.4 tonnes CO2eq. If also addressing energy supply reduction and energy recovery, some measures achieves a reduction of over 35 tonnes CO2eq, which results in enhanced economic viability from reduced operating costs. This study suggest that organizational constraints have to be addressed to successfully implement identified water saving measures. To allow economic motivation for all water saving measures in Tannefors, a payback period of over 7 years has to be applied, which can be lowered if the measure also reduces energy demand or increases energy recovery. In order to avoid sub-optimization of water saving measures, the current Water Management Hierarchy has to include the aspects of energy supply and energy recovery. If the aim is to reduce a corporation’s water use, the largest sites with heavy industrial processes should be addressed first. However, the potential impact from water related risks at smaller sites should not be neglected, in order to ensure safe operations and avoid increased costs in the company´s supply chain.
Tillgången av vatten blir alltmer ansträngd globalt, varför fokus på industriell vattenanvändning ökar. Den här studien undersökte hur industrier bör förhålla sig till vatteneffektivitetsprojekt, vilka organisatoriska begränsningar som bör hanteras, och vilka effekter vattenbesparande åtgärder har på ekonomiska kostnader, miljöpåverkan och påverkan från vattenrelaterade risker. Studien har genomförts på Saab Group. Primärdata för vattentillförselmängd och kostnad har erhållits från tolv platser för år 2018. Data från dessa siter har används för att uppskatta vattenanvändningen för de övriga 43 siterna som ingår i denna studie. Intervjuer med anställda inom Saabs organisation och med externa intressenter har fungerat som viktiga informationskällor, i kombination med undersökningar av interna företagsdokument. För att underlätta för företag att strukturellt ta itu med vatteneffektivitetsprojekt, så utvecklas Demingcykel-konceptet i den här studien. De inkluderade stegen är nödvändiga för att hantera viktiga identifierade organisatoriska begränsningar som är brits på kommunikation, brist på incitament för anställda och brist på ekonomiska incitament. Vidare, då vatten ofta är en energibärare, utvecklas en ny vattenminskningshierarki för att inkludera de sammanhängande aspekterna av energitillförsel och energiåtervinning. Potentialen för rörläckage och utmaningen att upptäcka dessa identifieras också. Om tiden från läckage till reparation under 2018 eliminerades, kunde den totala vattentillförseln i Arboga ha minskat med 10100 m3 vilket motsvarar 35% av total vattentillförsel till siten, respektive 35900 m3 och 42% i Björkborn. I Tannefors identifieras vattenbesparingsåtgärder för en ytbehandlingsprocess, en anläggning med testutrustning, och genom utnyttjande av grundvatten. Alla vattenbesparande åtgärder resulterar inte i minskade årliga driftkostnader, på grund av ett ökat energibehov. Vidare, om möjligheten för energiåtervinning förbises när reducering av vattenanvändning är målet, visar resultaten att ersättningen av ett kylsystem som använder kommunalt dricksvatten utan recirkulering med en luftkyld enhet, att utsläppen av växthusgaser kan öka. Under 2018, så skulle de simultant implementerbara vattenbesparande åtgärderna i Tannefors ha minskat vattentillförseln med 40600 m3, vilket motsvarar 22% av den totala tillförseln till siten. Utsläppen av växthusgaser hade samtidigt minskats med 0.4 ton CO2eq. Om även energitillförsel och energiåtervinning tas i beaktande, uppnår vissa åtgärder en minskning på över 35 ton CO2eq, vilket resulterar i förbättrad ekonomisk lönsamhet från minskade driftkostnader. Denna studie föreslår att organisatoriska begränsningar måste hanteras för att framgångsrikt genomföra identifierade vattenbesparande åtgärder. För att möjliggöra ekonomisk motivering för alla vattenbesparande åtgärder i Tannefors, måste en återbetalningstid på över sju år tillämpas, vilken kan sänkas om åtgärden också minskar energibehovet eller ökar energiåtervinningen. För att undvika suboptimering av vattenbesparande åtgärder, måste den nuvarande vattenhierarkin inkludera aspekterna av energitillförsel och energiåtervinning. Om målet är att minska ett företags vattenanvändning, bör de största anläggningarna med tunga industriprocesser först adresseras. Dock bör den potentiella påverkan från vattenrelaterade risker på mindre siter inte försummas, för att säkerställa säker drift och undvika ökade kostnader i företagets värdekedja.

Bioflocculation, which can be defined as aggregation of bacterial flocs, has important implications on the physical characteristics of sludge. It is especially critical to settling and dewatering systems which impacts the overall economy of the process greatly. One of the most common problems in activated sludge systems to negatively influence the settleability is sludge bulking which can be defined as non-settling situation of microbial mass. The first objective of this research is to investigate the effect of calcium ion on sludge bulking in a phosphorus deficient medium and the second objective is to improve the settling, dewatering, and pumping of activated sludge by adjusting the calcium (Ca) ion concentration of the feed. For this purpose, 7 semi-continuous laboratory scale activated sludge reactors were operated with a mixed aerobic culture. The reactors had 8 days of sludge residence time and aerated with air pumps to provide a dissolved oxygen concentration of at least 3 mg/L. All the analyses were conducted after the reactors reached steady state condition. In the first part of the research, the effect of strictly phosphorus-limited medium on bulking of activated sludge was studied at different calcium ion concentration. Three reactors were set up having 5, 10 and 20 meq/L calcium concentrations. From the results it was observed that, phosphorus deficiency caused viscous bulking independent from the calcium ion concentration. It was found out that bulking of activated sludges due to phosphorus deficiency could be cured by the addition of phosphorus. Furhermore, microorganisms starved for phosphorus, seemed to accumulate polyphosphate granules when they were exposed to a phosphorus source. In the second part of the study, the effect of calcium ion on physical, chemical and surface chemical properties of activated sludge was investigated at 4 different concentrations (0.27, 5, 10 and 20 meq/L) under sufficient phosphorus concentration. Calcium addition resulted in significant changes in the quantity and quality of extracellular polymeric substances (EPS). Total EPS increased depending on the calcium concentration. Carbohydrate content of EPS dominated over the protein content for calcium concentration of 5 meq/L and above. The amount of calcium ions incorporated into the sludge floc matrix also increased with the dose of calcium added. Settleability and dewaterability of sludge improved significantly at 5 meq/L dose of calcium. However, settleability did not change any further with increasing calcium dose, whereas dewaterability increased for all increasing calcium concentrations. Sludge viscosity also decreased considerably at 5 meq/L concentration indicating better pumpability but it did not change further above 10 meq/L calcium addition.

Досліджується проблема визначення еколого-правового статусу руслових водойм-охолодників конденсаційних теплових електростанцій України, яка виникає при державному обліку водопостачання. На прикладі судової інженерно-екологічної експертизи в адміністративній справі встановлено статус Добротвірського водосховища. Доведено, що інші подібні руслові водосховища-охолодники є елементами систем оборотного водопостачання теплових електростанцій.
The problem of determination of the environmental and legal status of riverbed water reservoirs-coolers of large condensing thermal power plants of Ukraine, which arises in the state accounting of industrial water supply, is considered. On the example of the engineering and environmental forensic in the administrative case the status of the Dobrotvir reservoir is established. It is proved that other similar riverbed water reservoirs-coolers are elements of systems of circulating water supply of thermal power plants.

For the appropriate operation and correct short term planning, daily demand curve (DDC) of municipal water distribution networks should be forecasted beforehand. For that purpose, artificial neural networks (ANN) is used as a new method. The proposed approach employs already recorded DDCs extracted from the database of ASKI (Ankara Water Authority) SCADA center and related independent parameters such as temperature and relative humidity obtained from DMI (State Meteorological Institute). In this study, a computer model was developed in order to forecast hourly DDCs using Matlab and related modules. Parameters that affect the consumption of the water were determined as temperature, relative humidity, human behavior (weekend or workday) and season. Randomly selected days were taken into account for performance of the ANN model. Forecasted DDC values were compared with recorded data and consequently the model gives relatively satisfactory results, an average of 75% match according to R2 values for Ankara N8-3 network. Same architecture was applied for Antalya network give better results, average of 85%. For planning purposes
total volume and peak water consumption values for the selected recorded days, the day before recorded days, ANN forecasted days and seasonal average was compared and seasonal average gave relatively better results. Using the forecasted DDC, (i) performance analysis of the pressure zone and (ii) optimum valve setting evaluation for pressure management were realized. The results of the study may help water utilities for short term planning of a water distribution network, rehabilitation of elements, taking counter measures and setting the valve openings for minimizing leakage and optimizing customer conformity of the distribution network.

Thesis; Thesis information not provided; 17 Jul 2003.
Published through the Information Bridge: DOE Scientific and Technical Information. "UCRL-LR-154423" Maxwell, R M; Tompson, A F B; Richardson, J H; El-Naser, H; Rihani, J. F F; Subah, A.; El Sha'r, W A; Al-Hadidi, Khair; Al-Awamleh, M; Al-Foqaha, M; Abu-Eid, O; Hayyaneh, R A. 07/17/2003. Report is also available in paper and microfiche from NTIS.

Thesis submitted in the requirements for the degree Doctor Technologiae: Chemical Engineering in the Faculty of Engineering at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2013
To date, limited information has been published on textile wastewater treatment, for re-use, in South Africa (SA), with treatment processes focusing on conventional wastewater treatment methods. A large contributor to the contamination of water within textile industries is from dyehouse processes. A major concern in textile wastewater treatment is the release of azo dyes and their metabolites, some of which are carcinogenic and mutanogenic, into the environment since they are xenobiotic and aerobically recalcitrant to biodegradation. A necessity therefore exists to find an effective treatment method capable of removing both the strong colour and the toxic organic compounds from textile wastewater. Membrane bioreactors (MBRs) are favoured when treating high-strength wastewater, since the membrane area is determined by the hydraulic throughput and not the biological load; no sludge is wasted and all bacteria are retained within the reactor, including specific bacteria capable of degrading the toxic, non-biodegradable constituents present in textile wastewater. MBR systems, using various configurations have been utilised extensively in the rest of the world to treat textile wastewater at both lab and pilot-scale. This DTech project formed part of a collaborative Water Research Commission (WRC) funded project K5/1900 - Pilot application of a dual-stage membrane bioreactor (dsMBR) for industrial wastewater treatment. The main purpose of this study was the on-site evaluation of a pilot-scale dsMBR incorporating two ultrafiltration (UF) sidestream membrane modules for the treatment, recovery and re-use of textile wastewater. The objectives of this project were to determine the treatment efficiency of the system; to evaluate the degree of colour removal from the textile wastewater; to improve residual colour removal within the system using treatment processes, such as NF and RO, as well as to propose a design and cost for a full-scale plant. A textile industry located in Bellville, Western Cape, was chosen as the industrial partner for the on-site evaluation of a semi-automated pilot wastewater treatment MBR plant using two 5.1 m2 Norit X-flow AirliftTM membrane modules. Since the wastewater treatment system was located on the premises, real continuously changing industrial wastewater was being treated. The industrial textile wastewater was treated in a series of tanks: 1) an anaerobic tank, which cleaved the azo bonds of the reactive dyes; 2) an anoxic tank containing reduced amounts of dissolved oxygen, in which denitrification occurred; and 3) an aerobic tank, in which i) nitrification, as well as ii) mineralisation of the aromatic amines occurred. The UF-membrane modules would account for the removal of any organic material. The wastewater stream was characterised by a chemical oxygen demand (COD) range of between 45 to 2,820 mg/L and an average biological oxygen demand (BOD) of 192.5 mg/L. The dsMBR achieved an average COD reduction of 75% with a maximum of 97% over the 220 day test period. The COD concentration obtained after dsMBR treatment averaged at 191 mg/L, which was well within the City of Cape Town industrial wastewater discharge standard. The average reduction in turbidity and TSS was 94% and 19.6%, respectively, during the UF-MBR stage of the system. Subsequent treatment of the UF permeate with nanofiltration (NF) for 4 days, alternated with reverse osmosis (RO) for 14 days removed both the residual colour and salt present in the UF permeate. A consistent reduction in the colour of the incoming wastewater was evident. The colour in the wastewater was reduced from an average of 659 ADMI units to ~12 ADMI units in the NF permeate, a lower American dye manufacturing index (ADMI) (i.e. method of colour representation) compared to the potable water (~17 ADMI units) utilised by the industrial partner in their dyeing processes. The colour was reduced from an average of 659 to ~20 ADMI units in the RO permeate, a lower ADMI and therefore colour when compared to the potable water. An average conductivity rejection of 91% was achieved with conductivity being reduced from an average of 7,700 to 693 μS/cm and the TDS reduced from an average of 5,700 to 473 mg/L, which facilitated an average TDS rejection of 92%. Based on the composition of the UF permeate fed to the RO membrane a maximum removal of 98.7% was achieved for both conductivity and total dissolved solids (TDS). The proposed full-scale plant would incorporate a UF-MBR system, followed by NF, RO, flocculation and a filter press. Therefore, the two waste products produced during operation of the proposed full-scale plant, would be the solid filter cakes and the liquid filtrate from the filter press. Implementing the proposed full-scale plant it would cost the industrial partner an operating cost of ZAR 113.85 and ZAR 3,415.49 to treat 97.1 m3 and 2,913 m3 of textile wastewater, respectively, per day and per month. This results in an annual saving of ZAR 845,848 on potable water expenses. This research, would provide SA textile industries, with an option to: 1) reduce their water consumption, thereby utilising less of a valuable decreasing commodity; 2) meet the SA government discharge standards and reduce their discharge costs; 3) reduce their carbon footprint (i.e. reduce their impact on the environment) by re-using their treated wastewater and therefore using less water from the municipality; and 4) decrease their annual expenditure on water, since the treated wastewater would be available for re-use.

Esta dissertação apresenta uma aplicação de inteligência artificial, a lógica fuzzy, estruturada como um controlador fuzzy, para a sintonia dos ganhos Kp e Ki de um controlador PI. Este último, configurado num conversor de frequência para a operação de um conjunto motor-bomba do sistema de abastecimento de água potável na região denominada de Recalque Mercês (RMER), na cidade de Curitiba, compreendendo 4 bairros com 140 km de tubulação e mais de 13 mil ligações a clientes. Hoje, o sistema funciona com controle PI tradicional de ganhos fixos, variando a velocidade do conjunto motorbomba, controlados por um sensor de pressão à jusante do bombeamento. Contudo, a variação de consumo de água potável fornecida é muito grande durante o período de um dia, sendo máxima no entardecer e mínima durante a madrugada, e com características sazonais, o consumo aumenta com o calor e diminui no frio, o que faz esse tipo de controle fixo ser ineficiente em determinados momentos. A proposta é adotar o controle fuzzy para alterar os coeficientes do controlador PI ao longo do dia, de forma autônoma, de acordo com o consumo instantâneo e assim, alcançar uma melhor eficiência energética do sistema, prezando pela qualidade do serviço prestado à população. Isto é, garantindo a vazão e a pressão de água para o consumidor. Por meio do MatLab®, mais precisamente os toolbox’s de simulação, Simulink® e SimScape®, foram criados dois modelos, um com o controle atual e o outro com a proposta inteligente, de uma abreviação da rede e do sistema de bombeamento da elevatória existente, a diminuição de 4 conjuntos motor-bomba para apenas 1 (um) e num trajeto único, perfazendo 5,4 km de distância, até o local denominado de ponto crítico, onde é mais longe, alto e difícil de se manter a pressão no patamar de 10 m.c.a. (1 bar), por norma. O controlador fuzzy desenvolvido possui 2 entradas, o nível do reservatório e a pressão à jusante do conjunto motor-bomba, e 2 saídas, os ganhos proporcional e integral para o PI. Com a estrutura baseado em regras, foram criadas 123 regras de inferência para que o sistema obtenha um desempenho favorável. As simulações foram realizadas com a referência de dados – 3 meses de histórico – de medições do reservatório e do sensor de pressão que é a realimentação do controle PI existente. Assim, a eficiência energética de 6,15% ao mês, em termos de energia elétrica consumida, foi conseguida, comparando com o modelo de controle tradicional.
This dissertation presents an application of artificial intelligence, the fuzzy logic, structured as a fuzzy controller, for the tuning of the Kp and Ki gains of a PI controller. The latter, configured in a frequency converter for the operation of a motor-pump assembly of the drinking water supply system in the region called Recalque Mercês (RMER), in the city of Curitiba, comprising 4 districts with 140 km of pipeline and more than 13 thousand connections to customers. Today, the system operates with PI traditional control with fixed gains, varying the speed of the motor-pump assembly, controlled by a pressure sensor downstream to the pumping. However, the variation in the consumption of potable water supplied is very large during the period of one day, being maximum at dusk and minimum during the dawn, and with seasonal characteristics, consumption increases with heat and decreases in the cold, which makes static control inefficient at certain times. The proposal is to adopt the fuzzy control to change the coefficients of the PI controller throughout the day, autonomously, according to the instantaneous consumption and thus achieve a better energy efficiency of the system, appreciating the quality of service provided to the population. That is, ensuring the flow and pressure of water to the consumer. Through MatLab®, simulation tools, Simulink® and SimScape®, two models were created, one with the current control and the other with the intelligent proposal. An abbreviation of the network and the existing pumping system of the lift, the reduction of 4 engine-pump assemblies to only 1 (one) and a single path, making 5.4 km distance, to the socalled critical point location, where it is further, higher and more difficult to keep the pressure at the 10 mwg (1 bar), as a rule. The developed fuzzy controller has 2 inputs, the reservoir level and the downstream pressure of the motor-pump assembly, and 2 outputs, proportional and integral gains for the PI. With the rulesbased framework, 123 inference rules were created for the system to perform favorably. The simulations were carried out with the reference of data – 3 months of historical – of measurements of the reservoir and pressure sensor that is the feedback of the existing PI control. Thus, the energy efficiency of 6.15% per month, in terms of electric power consumed, was achieved, compared to the traditional control model.

碩士
淡江大學
水資源及環境工程學系
88
In the study of research, we use the simply method of linear programming by a suit software ”ABQM’ to optimization the cost of ” Tainan Science-Based Industrial Park”. At the data of input ,the max provide of surface water every month has three rate base on 1000、1250、1500MCM of runoff .At the data of groundwater ,approximately 20﹪of annual precipitation is assumed to contribute to the recharge of this aquifer .The recharge area of the aquifer extends for approximately 20㎞ ,annual recharge is 6.748mcm.We fix the price of groundwater 1NT dollar (groundwater is free)、14.539NT dollars and the price of surface water 9NT dollars .Then we calculate the optimum cost by the suit software ‘ABQM ‘ . We utilize the consequence of the optimization to conclude the amount of the groundwater we draw monthly. If the groundwater is not enough ,we supplement the surface water and calculate the cost. That is namely the case B. The consequence indicate , when the groundwater price is 1NT,namely the groundwater is free, the resource of the water which we make choice is the groundwater. When the groundwater is not enough to use, then we choose the surface water. Although the optimization is the case A, we still choose the case B to avoid the groundwater which is extracted outside the limits of itself. When the groundwater price is 14.539NT dollars, the resource of the water we choose is the surface water, when the surface water is not enough to use , then we choose the groundwater. Summarily, case A is cheaper and more suitable than case B. Finally, because of the groundwater price has a great influence on the result of this study. But the groundwater price does not still have fixed price at present. The government should be order the groundwater price as soon as possible. In order to avoid the groundwater extracted too much , the price of the groundwater should be higher than the surface water price.

AECI Bioproducts (Bioproducts) is part of an industrial complex located at Umbogintwini, approximately 26 km south of Durban, Kwazulu-Natal. This system was selected for water pinch investigation, as it is one of the major users of freshwater on the complex and hence discharges a related quantity of wastewater, amounting to approximately 400 ML per annum. Bioproducts is a manufacturer of l-lysine, which is an animal feed additive. Water stream flowrate and purity data, as well as operating cost information, were obtained from plant records at AECI Bioproducts. Limiting flowrate and purity conditions for the water-using operations were established from a mass balance over the entire system using the Linnhoff-March software, WaterTracker. Subject to the specified constraints and operating costs, the problem was to determine the design of the water-using subsystem. No treatment plants were included in the study, as none exist at the facility. Three scenarios were investigated, which examined the operating variability of one of the evaporators on the site (the AS evaporator), which produces a condensate source of variable purity. The operating cost target and network design for each scenario was determined using the Linnhoff-March software, WaterPinch. Alterations from current operating practice were identified and associated savings (water-using network operating cost and freshwater flowrate) were highlighted. A robust optimal design was identified, with a recycle, which was consistent for all scenarios investigated. The degree of reuse of the AS evaporator condensate source was determined to be dependent on the purity of the source. The limiting constraint was identified at the sea pipeline, for suspended solids (SS): a prohibitively low discharge concentration constraint was identified as posing the major obstacle for saving. The potential for saving was investigated by incrementing the SS concentration constraint and subsequently the free and saline ammonia (FSA) constraint and allowing for the broth effluent to be discharged via the sea pipeline (which was previously disallowed by an effluent exemption). Although relatively small savings were identified through process integration (from 0.61% to 1.56% of the water-using network operating cost), the analysis identified a potential saving of over 70% of the water-using network operating cost, with relaxation of the sea pipeline SS and FSA constraint.
Theses (M.Sc.)-University of Natal, Durban, 2002.

碩士
中原大學
土木工程研究所
91
The Study of Supply and Demand about Industrial Use Water in Tao-Chiu Region Student: Shih, Hsien-Hsun Advisor: Lee, Chin-Dee The Department of Civil Engineering Chung-Yuan Christian University Abstract The safety and stability of the industrial water distribution is highly monitored, as the risk for lack of water is unbearable. The industrial manufacturing equipment must be in operation continuously, in order to deal with shortage of water supply in the long run. Thus, the conditions on industrial water distribution at the present or future state in these districts have to be monitored at all times, in order to maintain secured and stabled water supply. The research shows that the maximum daily water supply in Tao-Yuan district is around 104.26 thousand CMD, Hsin-Chu district is around 39.75 thousand CMD, an approximate of total of 144.01 thousand CMD of water is supplied daily. In the year 2021, the maximum daily water supply in Tao-Yuan district will be around 157.15 thousand CMD and Hsin-Chu district will be around 65.82 thousand CMD, with an approximate of total of 222.97 thousand CMD of water will be supplied daily. Presently, the Water Purification Work in these two districts is around 122.3 thousand CMD in Tao-Yuan and 39 thousand CMD in Hsin-Chu, a total of 161.3 thousand CMD of water is supplied, present water supplied is greater than the maximum daily water supplied of 144.01 thousand CMD, this unbalancing distribution is still manageable. In the future, these two districts will have to deal with water supply of 223 thousand CMD daily, besides the present water purification equipments, it would still need supports from Bao-Shan and the expansion of Bao-Shan Water Purification Work, in order to satisfy the needs in the year 2021.

A 616-year Douglas-fir (Pseudotsuga menziesii) chronology was developed to examine the history of drought and moisture variability in the Sooke Watershed, near Victoria, British Columbia. Ring-width chronologies were compared to historical precipitation, air temperature and drought variables (Palmer Drought Severity Index (PDSI) and Standardized Precipitation Index (SPI)) to determine the climate/radial-growth response to moisture stress on the sampled stands. Correlations between the ring-width chronologies and climate variables revealed that May to July precipitation, May-June SPI and July PDSI were significant limiting factors to radial-width growth. A transfer function was established for each of these variables to create a proxy climate reconstruction of drought in the watershed. The summer precipitation model provided the most accurate representation of past moisture variability (R2 = 0.20) and reveals substantial variation in precipitation over the past six centuries. Evidence from the periodicity of the tree-ring record to suggest that some modes of atmospheric circulation are influencing precipitation supply to the watershed.

Sappi's Ngodwana integrated Kraft pulp and paper mill was used as case study for the application and evaluation of the water pinch technique. The technique of water pinch originates from energy pinch, but uses mass flow and contaminant concentration to identify water and effluent reduction opportunities. The classical meaning of pinch, as defmed by energy pinch has however been changed to a more modem meaning. Historically the terms water or energy pinch was used to refer to the points where two composite curves touched on energy or water graphs. This graphical meaning of pinch is gradually being replaced to refer to the optimal po int proposed by a numerical solver beyond which improvement of the water network is no longer possible for the given inputs. The water pinch technique was applied by means of a numerical solver that used mixed integer non-linear programming to optimise to the minimum cost for running the water network under investigation. The problem defmition was defined in terms of costs associated with the use of utilities, raw material, treatment facilities and process units. It was also possible to define factors such as environmental impact, corrosion, fouling, scaling, cooling tower treatment cost, legal risk etc in terms of a penalty cost. The water pinch technique has been refined in software packages that are user friendly, ca~ble of handling multi-contaminants and suitable for varying flows. The software package WaterPinch by Linnhoff March was used. The case study was applied on Ngodwana mill that has an already highly closed water system with effluent generation rates as low 20 kL per ton of pulp and paper. The pinch study included sodium, chloride, calcium, suspended solids and COD as contaminants. The study investigated different applications of the pinch technique. The following was concluded: • The mill's understanding of its current restrictions, ()l pinch points, of its water network was confirmed. No new pinch points have been identified of which the mill was not aware. This indicates that the mill was already highly knowledgeable about its water system. This was expected of a mill that has a very low specific-effluent-generation rate. Water pinch was unable to significantly improve on the effluent generation rate of the mill. • The pinch analysis has identified opportunities of mixing small quantities of waste streams into process water streams to replace fresh water. These changes can introduce minor water savings and new risks to the process that have to be understood better before implementation. • The mill has progressed far with the design and costing of a proposed effluent treatment plant (ERPl). The integration of this treatment plant into the water network was investigated using the pinch technique. The pinch solver suggested a totally different approach to the integration of the ERPI plant compared to design of the mill. The mill's design revolves around the treatment of low chloride streams in the ERPl plant and using of the treated water as make-up to the cooling towers. Sodium was recovered as raw material from the cooling towers' blow-down. Pinch proposed treatment of the high cWoride containing streams and returning the streams to users suitable of using high chloride water. The network proposed by mill's design generates 8.2 MLlday effluent less than the pinch proposal, and recovers sodium as raw material. The proposal presented by pinch is not recommended and points to the difficulty in simulating factors, such as raw material recovery, in a pinch analysis. • Users for the excess storm water were identified using water pinch and will be suitable for implementation. The mill has mwever decided on alternative sinks for the storm water based on considerations such as process inter-dependency, risks associated with contamination and general management philosophy for the different systems in the mill. These considerations could have been included into the pinch solver, but were not because it was of interest what the second best option would be. • The pinch investigation proved useful to confirm certain understandings of the mill. The investigation confirmed the difficulty of improving the water systems of the mill due to the fact that Ngodwana is already a highly closed and integrated mill. Numerous smaller process changes have been identified by the pinch solver and could be investigated further for smaller process improvements. • It i; recommended that pinch technology be applied again when the mill plans to make major process changes or expansions. It is also recommended to use water pinch on a more frequent basis in smaller sections of the mill or for other evaluations in the mill. As a group Sappi could benefit from the use of water pinch, especially in situations where the water network of the mill is not already water efficient. • The recommendations and conclusions in this report have not been subjected to technical and economical feasibility studies. Extensive further studies must be conducted before implementation of any of the results. Further studies must include impacts from process dynamics, long term effects, impacts from other contaminants that have not been simulated, etc.
Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2009.

The objective of this investigation was to utilise water pinch analysis as a tool for the optimisation of fresh water use in an integrated pulp and paper mill. The investigation was carried out at Mondi Paper in Merebank, south of Durban. The pulp and paper manufacturing process is a large consumer of fresh water and minimising the amount of fresh water used in the processes is beneficial from both a cost and environmental point of view. There are examples of mills which have "closed" their water systems to the extent that fresh water make up is minimal and most of the water is recycled and reused in a closed loop. These examples provide guidance on the basis of proven methods for reducing water consumption in the pulp and paper industry and can be used as a reference for mills wishing to reduce water consumption by making use of tried and tested methods. This investigation sought to provide an alternative method to identifying potential savings in fresh water consumption by making use of water pinch analysis. This was done at Mondi Paper by analysing individual parts of the mill and then a larger section of the mill which included both pulp and paper production. Flow rates of water streams and fibre content in those streams were obtained from plant data, where available, and this data was used to produce.a mass balance using the Linnhoff-March software, Water Tracker. The balance produced using Water Tracker provided the missing flow and fibre content data and this data was used as the input for the Linnhoff-March software, Water Pinch , to perform the water pinch analysis. The results achieved when analysing the individual parts of the mill did not demonstrate potential for significant savings in fresh water consumption, however the analysis of the integrated section of the mill identified a potential reduction in fresh water. It was found that the application of a single contaminant analysis to the larger section of the mill identified a possible reduction in the freshwater requirement of 8.1% and a reduction in effluent generated of 5.4%. This is a savings of R1 548 593 per annum based on 2003 costs of fresh water and effluent disposal. This analysis was conducted using the most simplified representation possible to produce meaningful results in order to evaluate the effectiveness of water pinch analysis in optimising the fresh water consumption in an integrated pulp and paper mill. It is demonstrated that water pinch analysis is potentially a useful tool in determining the minimum fresh water requirement of a site.
Thesis (M.Sc.Eng.)-University of Natal, Durban, 2003.

International LCA literature indicates that little data is available pertaining to potable water production and supply, in particular with respect to the environmental burdens generated within the system. This study aims to investigate and assess the environmental burdens associated with the potable water supply to an industrial area (Rosslyn, north of Pretoria, in the Tshwane Metropolitan Municipality). The procedure, as well as the assessment of the environmental impacts of a life cycle, is dependent on a comprehensive life cycle inventory (LCI) of the evaluated system. Water use is included in LCIs, which are incorporated into the LCIA procedure, as it reflects a direct extraction from available resources. The water supply system diagram has been developed and data was collected, treated and analysed in the inventory analysis phase. The study closely followed the four phases as stipulated in the International Organization for Standardization (ISO 14040 series of standards) for conducting LCAs, including: -- goal and scope definition; -- LCI analysis; -- LCIA; and -- interpretation, conclusions and recommendations. The methodology used in the impact assessment phase was the introduced LCIA framework for South Africa in order to determine the extent of different environmental impacts. The inventory analysis, conforming to the scope of the study, provided an overall inventory of energy and other resource requirements, emissions to water and air, dust fallouts and solid or liquid wastes for the system under study. By using this methodology and by tracing all unit processes involved in the potable water supply system, the main contribution to the environmental burdens imposed on the potable water supply system was found to be the extraction of the required water from nature to supply potable water to Rosslyn. The toxicity potential impacts on water resources, mainly due to the electricity required for the water supply system, are of minor importance. This conclusion is valid for the system investigated, and as a result, the recommendations for environmental improvements should focus on water losses that must be addressed foremost. What is required at this stage is strategic planning regarding the extraction, use and conservation of water resources. Furthermore, to optimise all processes of water extraction, and to make them more efficient, electricity and other energy inputs are also of importance, albeit to a lesser extent.
Dissertation (M (Applied Sciences : Environmental Technology))--University of Pretoria, 2007.
Chemical Engineering
unrestricted

Pinch Analysis, in the broadest sense, is concerned with the optimal use of resources (material or energy) in a multi-process system. Pinch Analysis based techniques have emerged for water systems over the past decade. A major assumption that has been made in applying these techniques is that a process system can be segregated into a set of process streams and a set of water streams. With this distinction in place, only the water streams are considered in the Pinch Analysis with the process streams represented implicitly. This approach has obvious limitations in situations where a clear distinction between process streams and water streams cannot be made. The chlor-alkali process is an example of a system in which the clear distinction between process streams and water streams cannot be made. Water is intrinsically involved in the process, serving as a carrier medium for raw materials and eventually becoming part of the products produced by the complex. Hydrochloric acid and caustic soda are reagents which are both used within and produced by the complex. These reagents are required by the process at a range of concentrations and the concentrated reagent is diluted to the required concentrations using demineralised water. Within the chlor-alkali complex, a number of effluents containing the reagent species are available and are typically sent to drain. It is conceivable that these effluents might be recovered and used for dilution purposes instead of demineralised water. This would bring about a reduction in the amount of water and concentrated reagent used and the amount of effluent produced by the complex. Given the economic value of these reagents relative to water, their recovery, if feasible, is likely to dominate the optimal water-use and effluent generation strategy. Current Water Pinch Analysis theory relies on the distinction being made between process streams and water streams and does not consider the recovery of reagents or the presence of desirable species within the system. In addition, the assumption is made that species are non-reactive; reactive species such as hydrogen chloride and sodium hydroxide, fall outside the scope of the current theory. The objectives of this study have included the development of an approach which is able to address these limitations of the existing theory. This approach, termed Combined Water and Materials Pinch Analysis seeks to identify optimal use strategies for raw materials and reagents, in addition to water-use and effluent generation. The approach combines mathematical programming with conceptual insights from Water Pinch Analysis. The approach is based on the optimisation of a superstructure which represents the set of all possible flow configurations for water, reagents and raw materials between the various operations within the process system; this problem is solved as a nonlinear programming (NLP) problem using standard optimisation tools. The application of the developed approach to the Sasol Polymers chlor-alkali complex at Umbogintwini, south of Durban, has been a further objective of this study. Given the variety of process operations present within the complex, which differ both in terms of their physical structure and function, individual process models for these operations were required. These models were described in terms of four basic functional elements, namely, mixing, flow separation, component separation and reaction, and incorporated into the superstructure. Given the complexity of the problem, the process system was divided into three subsystems which were optimised in isolation from each other. These results were subsequently integrated to reflect the performance of the subsystems in combination with each other. The results showed a potential reduction of 14% in water-use and 42% in effluent production by the complex, relative to the existing operating configuration. Amongst other savings in material use, the results indicated a 0.2% reduction in the use of salt, a 1.6% reduction caustic soda use and an 8.3% reduction in the use of hydrochloric acid. Economically, the potential saving identified was R 945 727 per annum, based on operating costs in the year 2000. The final objective of this study was the interpretation of the pinch as it relates to the Combined Water and Materials Pinch Analysis problem. A general definition of the pinch was proposed; according to this definition, the pinch corresponds to that constraint or set of constraints which limits the performance of the system, that is, prevents it from further improvement. For the Combined Water and Materials Pinch Analysis problem, this performance is measured in terms of the operating cost. This definition is thus a departure from its usual thermodynamic interpretation of the pinch; in addition, the pinch is defined in terms of a constraint or a set of constraints instead of a point. These constraints are identified by an analysis of the marginal values provided by the optimisation algorithm. Marginal values are also used as a means of identifying process interventions which may be effected such that the performance of the system may be improved further.
Thesis (M.Sc.Eng.)-University of Natal, 1989.

Climate change has affected diverse physical and biological systems worldwide. The impact of climate change on water resources is one of the most important. Even though the world’s water resources are rapidly deteriorating due to the combined effects of climate change, population growth and fast urban development, climate change has been posing new challenges to water resources managers. Uncertainty of the climatic pattern is a major challenge for water authorities to formulate effective water management policies according to the prevailing and future climatic conditions.

Water resources systems are operated for many uses such as for municipal water supply, irrigation, hydro-electric power generation, flood mitigation, storm drainage, and for recreation. Water resources systems may also serve as places of cultural and spiritual significance. Decision-making in this context is inherently multicriterial, often requiring multi-disciplinary participation with a view to seeking an optimal solution or, at best, a compromise between conflicting interests for water. Water resources planning involves a thorough understanding of not only the quantitative aspects such as the volumes of water harvested and released from reservoirs but also of the qualitative factors that underpin the shared vision for the operation of water resources systems for the benefit of all stakeholders. The aim of this study was to develop a structured multi-objective optimisation procedure for the optimisation of operation of water resources systems considering climate change. For this purpose, the integration of quantitative and qualitative information of water resources systems was achieved using a combined multi-objective optimisation and sustainability assessment approach as part of a three-phase procedure. This procedure was tested through the preparation of optimal operating plans for a case study of the Wimmera-Glenelg Water Supply System (WGWSS), assuming a range of hydro-climatic conditions. The WGWSS is located in north-western Victoria in Australia and is a multi-purpose, multi-reservoir system which is operated as a single water resources system; with many possible combinations of operating rules.

Cape Town, South Africa, falls within a winter rainfall region, making it difficult to assess the feasibility of rain- and stormwater harvesting. The reason for this is because the region’s high water demand period coincides with the low rainfall summer season, thereby limiting the availability of this alternative water resource when most needed. During this study, rainwater harvesting for toilet flushing purposes, collected from roof surfaces, was practically assessed by means of inserted flow meters at a pilot study site in Kommetjie, Cape Town. The combined and single system roof- and land surface runoff yields and savings of commercial buildings within the Kommetjie business area, were also theoretically assessed by making use of a mathematical roof- and land surface runoff model specifically developed during this study. The statistical testing of the hypotheses statements relating to the pre- and post-harvesting savings at the pilot study building, compared against the average actual municipal water usage, were performed. Hypotheses testing were also performed in order to compare the theoretical rain- and stormwater runoff yields for the commercial business area against the average actual municipal water consumption. The conclusions drawn from this study indicated that valuable potable water, as well as related financial savings, can be achieved within a winter rainfall region, thereby making rain- and stormwater harvesting a feasible option for commercial businesses in Cape Town.
Environmental Sciences
M.Sc. (Environmental Management)