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Tratamento do Efluente Gerado nas Atividades de Limpeza de Caminhões de Lixo / Effluent treatment of garbage trucks cleaningZilton José Sá da Fonseca 23 June 2006 (has links)
Este estudo abordou o tratamento de efluentes gerados na operação de lavagem de caminhões de coleta de lixo do tipo IIA e IIB, conforme a NBR 10.004. Os ensaios foram realizados na estação de tratamento localizada na garagem da empresa Koleta Ambiental, Rio de janeiro. Em face dos grandes volumes de água exigidos para a limpeza dos caminhões foi realizado ensaio de tratabilidade a fim de definir qual o método de tratamento mais adequado para o efluente. Foram ensaiados os métodos físico-químico, biológico e ultrafiltração com membrana. O objetivo final era verificar a qualidade da água para posterior reuso a fim de diminuir o desperdício de se usar água potável para a lavagem de caminhões de lixo. Os resultados mostraram-se satisfatórios, porém há a necessidade de se aprofundar a pesquisa para enquadramento de vários parâmetros de qualidade nos padrões das das Resoluções CONAMA 357 e 274, assim como melhorar a avaliação do consumo de energia no processo de filtração com a membrana. / The present study, undertaken at the site of koleta Ambiental S.A., Rio de Janeiro, a company specialized in garbage collection, was related to the tratability tests of the wastewaters generated by garbage truck cleaning. To verify the effectiveness of these tests, a sequence of treatment related to physicochemical, biological and ultrafiltration through membranes tests, was adopted. From the results, one can conclude that further investigations should be carried out, as some water quality parameters of the treated wastewaters, such as chlorides and nitrogen that still do not comply with those prescribed in CONAMA 357 and 274 resolutions. Moreover, as far as the energy consumption related to ultrafiltration tests, must be further assessed, as the results which have been obtained were not conclusive.
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Conservação de Água, Tratamento, reuso e Reciclo de efluentes em Refinaria de Petróleo / Water Conservation, Effluent Treatment, Reusing and Recycling at Petroleum RefineryJosé Henrique da Silva Carvalho 20 June 2006 (has links)
Nesse estudo foram analisados os principais resultados do programa de conservação de água e reuso e reciclo de efluentes aquosos em refinarias de petróleo. As principais ações empregadas visando a conservação (redução) do uso de água foram: implantação de programas de conscientização, modificações de projeto e otimização de processo. Na etapa de reuso buscou-se avaliar a compatibilidade quali e quantitativa dos efluentes aquosos com o intuito de reaproveitá-los como água reposição de outros processos industriais. Na etapa de reciclo, procurou-se melhorar a qualidade do efluente final da refinaria através de otimização da estação de tratamento de efluentes com o intuito de reaproveitá-lo no sistema de resfriamento (fechado), principal consumidor de uma refinaria. O resultado das ações de redução (conservação), reuso e reciclo foi uma redução de consumo de água de, respectivamente, 108.000, 6.100 e 130.000 m anuais. Outro resultado conseguido foi uma melhoria ambiental através da redução da vazão de efluente (80%) bem como redução da concentração dos principais contaminantes (DQO, DBO, sulfeto, óleos e graxas, sólidos suspensos, fenol e nitrogênio amoniacal). A redução do efluente após a implantação do programa foi de 80% em relação à inicial. Por fim, após análise técnico econômica do referido projeto tendo como resultado um tempo de retorno de investimento de nove meses, confirmando ser um empreendimento extremamente atrativo, demonstrando que é possível racionalizar o uso de recursos naturais, melhorar qualidade do meio ambiente e realizar bons resultados econômicos simultaneamente. / In this study the main results of water conservation and effluent reusing and recycling programs at petroleum refinery was analyzed. The main actions used to look for water conservation (reduction) were: implanting of personnel training program; plant design changes and process optimization. At reuse step the objective was to evaluate the compatibility of aqueous effluents in order to reuse it as make-up water at other industrial processes. At recycle step, the purpose was to improve the refinery effluent quality by effluent treatment station optimization in order to recycle it at cooling system, the higher water consumer at a refinery. The results of conservation, reuse and recycle actions provide the reduction of water consumption of, respectively, 108,000, 6,100 and 130,000 m3/year. Another important result was an environmental improvement by a reduction of final effluent flow rate, besides the reduction of the concentration of mainly contaminants (COD, BOD, sulphide, oils and greases, suspended solids, phenol and ammoniac nitrogen. The total reduction of effluent flow rate was 80% relative to initial status. Finally, a technical economical analysis of global program was made and showed nine months as returning rate of investment, confirming that was an extremely attractive design, proving that its possible to rationalize natural resources, improve environmental quality and gain good economic results simultaneously.
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Reúso de água em indústria metalúrgica rolamenteira - estudo de caso da SKF do Brasil Ltda. / Reuse of water in bearing industry - case study of SKF of Brazil Ltda.Romário Maron Júnior 25 April 2006 (has links)
Com a globalização do mercado, muitas empresas procuraram se modernizar objetivando tornarem-se mais competitivas, com o crescimento industrial os recursos naturais apresentam-se mais escassos levando ao desenvolvimento de leis ambientais cada vez mais rígidas. Os custos envolvidos com o uso dos recursos naturais, têm levado as indústrias a buscarem alternativas a curto e médio prazos para minimizarem estes custos, procurando reduzir os seus impactos ambientais. A busca para um menor consumo de água através de técnicas de reúso e reciclagem nos processos industriais passam a fazer parte do planejamento estratégico de várias empresas, inclusive das rolamenteiras. O presente trabalho foi desenvolvido com o objetivo de avaliar o potencial de reúso da água da atividade de tamboreamento de rolos cônicos com espessura entre 5 a 8 mm e altura de 6 a 8 mm, sendo uma atividade de suma importância para garantir um padrão de qualidade satisfatório, de forma que as atividades subsequentes sejam efetuadas sem anomalias técnicas, conduzindo à obtenção de um produto final de qualidade. Por não requerer uma água com padrões elevados de qualidade, neste trabalho foi demonstrado o potencial de reúso de efluentes na atividade de tamboreamento, viabilizando-se sobre maneira o objeto deste estudo, onde é possível avaliar os aspectos físicos e químicos antes e após o tratamento da água para futura implantação contínua. / With the globalization of the market, many companies had looked for to be modernized for becoming more competitive. With the industrial growth, natural resources scarcity, and environmental pollution result in the development of more stringent laws. The costs associated with the use of the natural resources are taking the industries to search alternatives of short and long terms to minimize these costs looking for the reduction of its environmental impacts. The searching for reduced water consumption through techniques of reuse and recycling in its processes start to be integrated in the strategic planning of some companies including the bearing industry. The present work has been developed with the objective of evaluating the potential of water reuse in the activity of tumbling conical coils with thickness in the range of 5 to 8 mm, and height of 6 to 8 mm, being an activity of utmost importance to guarantee a satisfactory quality standard, in order that the subsequent activities are effected without anomalies, leading to the attainment of an end product of quality. By not requiring water with high standards of quality, in this work the potential of effluent reuse was demonstrated in the activity of tumbling, making possible to achieve the objective of this study, where it was possible to evaluate water physical and chemical aspects before and after the treatment for future implantation in continue way.
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Avaliação do processo de eletrodiálise reversa no tratamento de efluentes de refinaria de petróleoMachado, Mara de Barros January 2008 (has links)
Este trabalho teve como objetivo avaliar a aplicação da eletrodiálise reversa no tratamento de efluente final de refinaria para reuso em sistema de resfriamento. O estudo foi conduzido nas instalações da Refinaria Gabriel Passos (REGAP)- MG, com efluente real, proveniente da saída da Estação de Tratamento de Despejos Industriais (E.T.D.I.), e utilizando para os testes uma unidade-piloto de eletrodiálise reversa com capacidade de tratamento de 2 m3/h. A utilização do processo de dessalinização por EDR teve o objetivo de reduzir sólidos totais dissolvidos no efluente de aproximadamente 1.240 mg/L para 310 mg/L, o que equivale a cloretos de 460 mg/L e 100 mg/L respectivamente, para atingir a qualidade requerida para água de make-up da torre de resfriamento da REGAP. Inicialmente foi feita uma avaliação comparativa com o processo de osmose inversa, no qual foi constatada, com o uso da EDR, a maior continuidade operacional, menores problemas de incrustação e menor exigência para o pré-tratamento do efluente. No estudo com a EDR foram realizados testes variando-se a vazão, de 600 a 2000 L/h de produto; voltagem de 200 a 370V e número de estágios. Durante os testes foi realizado o monitoramento operacional e analítico da água de alimentação da EDR, do produto (solução diluída) e do rejeito (concentrado salino), sendo os dados avaliados e correlacionados para determinação da densidade de corrente, taxa hidráulica, eficiência e taxa de remoção de sais. A análise da formação de incrustações e deposições na superfície das membranas levou ao estabelecimento de um procedimento de limpeza química. O estudo foi conduzido de forma a obter a otimização da operação com rendimento necessário na remoção de sólidos dissolvidos, menor custo energético e de manutenção. Após os testes foi selecionada a condição otimizada da unidade piloto: módulo em 2 estágios, vazão de 1,1 m3/h e voltagem de 275V. Para este condição o consumo energético foi de 1,95 KWh/m3 de efluente tratado. Os resultados mostraram a viabilidade técnica-econômica do uso da EDR para remoção de sais de efluente final de refinaria para aplicação em reposição de sistemas de resfriamento. / This study aimed the evaluation of the application of electrodialysis reversal in final effluent treatment targeting the reuse in cooling towers. The study was done in Gabriel Passos Refinery (REGAP) - MG, with real effluent, from the Industrial Effluent Treatment Station (ETDI), and was held in a pilot plant of electrodialysis reversal with a treatment capacity of 2 m3 / h. The use of the desalination process with EDR target the reduction of total dissolved solids in the effluent of about 1.240 mg / L to 310 mg / L, equivalent to chlorides of 460 mg / L and 100 mg / L respectively, to reach the required quality of make-up water in the REGAP cooling tower. It was originally done a comparative evaluation with reverse osmosis process, another method of membrane desalination. Electrodialysis was selected because of its operating stability, less problems with scaling and fouling, dispensing the use of conditioning chemicals, and the requirement of a simpler pre- treatment The tests with EDR were carried out ranging the product flux for 600 to 2.000 L/h, the voltage for 200 to 370V and the number of hydraulic stages. During the tests were analyzed operational and analytical data in the EDR feed, product (diluted solution) and reject (concentrated solution), being the parameters analyzed and correlated to determine the current density, hydraulic rate, efficiency and salts removal rate. The analysis of fouling and deposition formation on the membranes surface led to an establishment of a chemical cleaning procedure. This study was conducted in order to obtain the operational optimizing with the necessary income to remove dissolved solids, with lower energy cost and maintenance. After the tests was selected the optimum condition for the pilot plant: stack in 2 stages, flow rate of 1.1 m3/h and voltage of 275V. In this condition the power consumption was 1.95 KWh/m3 of treated effluent. The results showed the technical and economic feasibility for the EDR in removing salts from refinery effluents for reuse in make up of cooling systems.
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Reúso de água em sistemas aeroportuários utilizando o processo de ultrafiltração. / Water reuse in airport systems using ultrafiltration process.Luana Di Beo Rodrigues 20 August 2012 (has links)
O intenso crescimento populacional associado à demanda excessiva de água, principalmente em grandes centros urbanos, tem comprometido de forma significativa os recursos hídricos tornando-os escassos em muitas regiões. Frente a este cenário a adoção de medidas que proporcionem a conservação da água nas diversas atividades nas quais ela é utilizada é de grande relevância. Neste contexto, medidas como o uso racional e a prática do reúso de água são opções que devem ser consideradas para combater a escassez induzida. No caso do reúso de água é possível utilizar efluentes, tratados ou não, como fonte alternativa às demandas para usos menos restritivos, preservando a água de melhor qualidade para aplicações mais nobres, como o consumo humano. Assim, neste trabalho foi avaliada a viabilidade técnica da utilização de efluentes secundários submetidos ao tratamento complementar por membranas de ultrafiltração, do tipo fibra oca, para atendimento de demandas não potáveis em sistemas aeroportuários. O estudo foi desenvolvido através da operação de uma unidade piloto de membranas, instalada na saída do sistema de esgotamento sanitário do Aeroporto Internacional de São Paulo/Guarulhos Governador André Franco Montoro. Por meio de ensaios específicos as condições ótimas de operação foram estabelecidas, pressão de 0,9 bar (90 kPa), frequência de retrolavagem de 40 minutos e frequência de limpeza de 200 h, sendo que a taxa de recuperação de água no sistema permaneceu em torno de 70%. O desempenho do sistema em relação à remoção de contaminantes foi avaliado verificando-se as porcentagens de remoção de Cor, Turbidez, DBO5,20, DQO, Carbono Orgânico Dissolvido, Absorbância de radiação UV (254 nm) e Coliformes Termotolerantes, obtendo-se remoções de 89%, 99%, 70%, 78%, 80%, 36% e 100%, respectivamente. Com base nos resultados das análises foi possível concluir que a água produzida pelo sistema de membranas apresenta potencial para atender aos seguintes usos não potáveis: irrigação de áreas verdes, descargas em bacias sanitárias e mictórios, lavagem de pitas e reserva para combate a incêndios. Como a água produzida pelo sistema de membranas apresentou concentrações elevadas de Nitrogênio Amoniacal, Fosfato e Matéria Orgânica recomenda-se um estudo mais detalhado da estação de tratamento biológico, antes de utilizar para atender a esse fim. / The excessive demand for water associated with intense population growth, principally in large urban centers, has significantly compromised water resources and transformed the situation in many regions to a scarcity status. Faced with this scenario, it is of great relevance to adopt measures that promote the conservation of water, through various activities and uses. In this context, rational water use and water reuse are measures that should be considered to tackle the induced shortage. In the case of water reuse, it is possible to use effluents, treated or untreated, as an alternate source for uses that have less stringent quality standards. This in turn, preserves the higher quality water for more demanding water uses, such as human consumption. In this study, we evaluated the technical feasibility of the use of secondary effluents, subjected to ultrafiltration membrane treatment (hollow fiber), to meet the non-potable demands of airport systems. The study was conducted with a pilot plant membrane, installed and operated at the sewage system discharge at the International Airport of São Paulo/Guarulhos Governor André Franco Montoro. Specific tests were conducted to establish optimum operation conditions: 0.9 bar (90 kPa) of pressure, a backwash frequency of 40 minutes, a cleaning frequency of 200 hours, and a recovery rate maintained around 70%. The system performance with respect to contaminant removal was evaluated by determining the percent removal of color, turbidity, BOD5, 20, COD, dissolved organic carbon, UV Absorbance (254 nm), and coliform, which yielded removals of 89%, 99%, 70%, 78%, 80%, 36%, and 100%, respectively. Based on analysis results, it was concluded that the water produced by the membrane system has the potential to supply the following non-potable uses: irrigation of green areas, discharges in toilets and urinals, floor washing, and firefighting reserves. As the water produced by the membrane system had high concentrations of ammoniacal nitrogen, phosphate, and organic matter, a more detailed study is recommended before using the effluent in cooling towers.
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The health and survival of fish exposed to wastewater from Motetema wastewater treatment plant, Sekhukhune DistrictMokgawa, Makubu Priscilla January 2020 (has links)
Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2020 / The pressing state of South Africa’s freshwater resources due to pollution from the release of raw sewage or poorly treated domestic wastewater, has resulted in the urgent need for the implementation of innovative ways to mitigate this problem. A proposed solution by the Council of Science and Industrial Research (CSIR) is to introduce different cultures of algae in wastewater treatment ponds where facilities have aged and become dilapidated. In turn fish are introduced into sewage maturation pond treated with algae to reduce algal biomass. The assumption being that if fish can survive under these conditions, the nutrients assimilated will be converted into fish biomass when ingested, in an attempt to decrease aquas nutrient loads. The aim of the study was to assess the health and survival of Oreochromis mossambicus exposed to wastewater from the Motetema wastewater treatment plant (WWTP) and to establish the extent to which this species consumes micro-algae within the water column. The aim was accomplished by assessing the consumption of algae by O. mossambicus based on algal cell density counts in fish aquaria and to establish the feeding ratio of fish based on stomach content fullness as well as to monitor the survival rate of O. mossambicus exposed to various concentrations of sewage water over a 96-hour period.
To establish fish survival under wastewater conditions, a 96-hour experiment was conducted in glass tanks (60 L), whereby the health and mortality of O. mossambicus exposed to different concentrations of domestic wastewater from Motetema WWTP was investigated. One set of aquariums supplied with compressed air via the use of diffusers while the other set of aquariums were void of aeration so as to simulate conditions at the treatment plant. Treatments comprising of four concentrations of 25, 50, 75 and 100% wastewater and a control of 0% were used. Water quality parameters were monitored every four hours and mortalities were recorded. Water samples were collected twice a day and sent to Capricorn Veterinary laboratory for nutrient analysis. Gill samples were also collected and sent to Onderstepoort Veterinary Institute for histological sections analysis. To assess the consumption of algae, 18 tanks (60 L) were set up in the laboratory, whereby three aquariums served as a control void of algae with the remaining tanks dosed with two algal species (Chlorella vulgaris and Chlorella protothecoides) of concentrations of 33%, 66% and 100%, over a period of ten days. Counts of algal density before and during the course of the experiments were done using a handheld flourometer. Upon mortalities and on the fifth day, fish were randomly selected from fish tanks, euthanised and stomach contents analysed. The stomach of fish was rated based on the percentage fullness and categorised as being empty, ¼ full, ½ full, ¾ full, full or gorged. When mortalities occurred, fish were dissected and their stomach contents analysed for fullness. Upon completion of the trial, two fish per treatment were euthanised and their stomach contents evaluated for algal consumption. Fish remaining at the end of the fish trial were counted and weighed to calculate the weight gain and specific growth rate. Survival rates were also determined. Water quality parameters were monitored three times a day over the duration of the trial. Water samples were collected every second day and send to Capricorn Veterinary laboratory for nutrient analysis. All mortalities were recorded over the duration of the trial period. In exposure and survival trials, physico-chemical parameters of water from the experimental tanks were within the acceptable limit for the growth and survival of O. mossambicus, except for dissolved oxygen and ammonia concentrations. Ammonia levels and mortality rates were significantly higher (p< 0.05) in treatments with wastewater, with ammonia levels exceeding those considered toxic for O. mossambicus. High ammonia concentrations resulted in definite histopathological changes in the gills as well as fish mortalities. After exposure to wastewater moderate signs of aneurism of the gill lamella, mild epithelial lifting, focal hyperplasia and clubbing of the terminal end of the secondary lamellae were recorded. Lesions are explained as a defence mechanism where gills increase the distance between the external environment and the blood, thus serving as a barrier to the entrance of the contaminants. Furthermore, results indicated that effluent levels >25% were detrimental to the fish. Fish survival decreased when exposed to effluent water, with higher number of mortalities recorded in tanks with no aeration. A 100% survival was observed in tanks with 25% treated wastewater in both aerated and non-aerated aquariums. The presence of fish mortalities in treatments >25 domestic wastewater shows that conditions at Motetema WWTP will be unfavourable for fish. Thus, results from the study indicate that domestic wastewater would need to be diluted to less concentrated levels to ensure the survival of fish and mechanical aerators needs to be deployed to increase oxygen levels in treatment ponds.
Water quality parameters for the second set of experiments fell within the recommended range for the growth and survival of fish. However, low oxygen levels were recorded from the control group with minimum values of 1.8 mg/l and maximum concentrations of 3.6 mg/l. Furthermore, temperature and pH ranges recorded during this study fell within the desired range for growth and reproduction of Chlorella vulgaris and Chlorella protothecoides. Nutrient concentration (phosphates, sulphates and nitrate) for this study were low, however ammonia and nitrite were above the acceptable level for fish growth and survival. The presence of fish resulted in increased levels of ammonia. High ammonia levels were not mitigated by algae in the tanks. However, the high ammonia levels decreased with the increasing number of fish mortalities. There were slight decreases in chlorophyll-a concentrations over the study period, from tanks comprising of algae and, tanks comprising of algae and fish. Decreases in chlorophyll-a concentrations in tanks with fish were linked to consumption of algae by the fish. This was verified by the presence of algae in the stomach of fish euthanised during and at the end of the experiment. In tanks without fish, decreases in chlorophyll-a concentrations could be attributed to plankton die offs, as aquariums had algae that had settled at the bottom of the tanks. Although, consumption of algae by fish was observed in this study, no full stomachs were recorded over the experiment period. Tanks with 66% algal concentrations had low survival rates. Better survival was observed from treatments with 33% algal concentrations. Toxic secretions could have attributed to the high mortality rate or low survival rates during the study period in tanks with 66% and 100% algal concentrations. In addition to this, ammonia and nitrite values that were above tolerable limits for fish could have also contributed to the high mortality rates (>80%). The use of fish in the tanks as a means to assimilate the algae, seemed to have an opposite effect than the desired one. As the presence of fish in tanks increased ammonia levels, therefore, the effluent would need to be further treated before it can be re-used or released into the environment. Further experiments would need to be conducted to establish whether negative influences could be neutralised, when other species such as Scenedesmus spp. are used together with Chlorella spp. for the treatment of wastewater, in order to make the environment suitable for fish survival. / DSI-NRF SARChI Chair (Ecosystem Health), Flemish Interuniversity
Council (VLIR-OUS)
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Efficacy of Tailwater Recovery Systems as an Approach to Water Resource ConservationOmer, Austin R 06 May 2017 (has links)
Water conservation practices are being widely implemented to alleviate sediment and nutrient losses from agricultural land and unsustainable groundwater use for irrigation. Tailwater recovery (TWR) systems are conservation practices being implemented to collect and store runoff to reduce nutrient losses and provide a source of irrigation water. This collection of research is focused on evaluating TWR systems through the following actions: 1) investigate ability to reduce solids and nutrients delivery to downstream systems, 2) compare differences in solid and nutrient concentrations in surface water samples from TWR systems to irrigation water from a TWR systems; 3) determine the potential to irrigate water containing solids and nutrients; 4) quantify a water budget for TWR systems; 5) conduct cost and benefit analyses of TWR systems; and 6) analyze economic cost to reduce solids and nutrients and to retain water. Tailwater recovery systems did not significantly reduce concentrations of solids and nutrients; however, loads of solids, P, and N were significantly reduced by 43%, 32% and 44%, respectively. Mean nutrient loads per hectare available to be recycled onto the landscape were 0.20 kg ha-1 P and 0.86 kg ha-1 N. Water budget analyses show these systems save water for irrigation but were inefficient. Net present value (NPV) and benefit cost ratios were positive and >1 for producers who owned the land, but remained <1 if land was rented. However, beyond improvements to irrigation infrastructure, farms with a TWR system installed lost NPV of $51 to $328 per ha. Mean total cost to reduce solids using TWR systems ranged from $0 to $0.77 per kg, P was $0.61 to $3,315.72 per kg, and N was $0.13 to $396.44 per kg. The mean total cost to save water using TWR systems ranged from $189.73 to $628.23 per ML, compared to a mean cost of groundwater of $13.99 to $36.17 per ML. Mechanistically, TWR systems retain runoff on the agricultural landscape, thereby reducing the amount of sediment and nutrients entering downstream waterbodies and provide an additional source of water for irrigation; however, more cost-effective practices exist for nutrient reduction and providing water for irrigation.
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Heavy metals uptake by wheat under two transpiration ratesSalah, Sharif Ali. January 2001 (has links)
No description available.
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Water reuse in peri-urban areas : A case study of Kibondemaji, Dar es Salaam,TanzaniaJohansson, Niklas, Karlsson, Saga January 2019 (has links)
An increasing number of countries worldwide is becoming water-stressed, sub-Saharan Africa being one of the most recurrent regions within this discourse. Tanzania, one of the countries in the region, is no exception: large population growth has increased pressure on its precious water resources. The largest city, Dar es Salaam, has a poorly maintained and dimensioned water supply and wastewater system. However, as this system expands and more people are given access to the water network, the water consumption of the city is expected to increase. This is problematic for the whole city; however, peri-urban areas suffer the most from its consequences, e.g. periodical water shortages. This report seeks to investigate the potential for saving water in one of these peri-urban areas, Kibondemaji, by looking at fields of application and techniques for reuse of wastewater from showers. This is done via a literature review and interviews in the field in order to analyse and compare the different systems – reuse for tap water, irrigation and toilet flushing. The interviews showed that there is wide acceptance within the community for water reuse for toilet flushing but not for tap water or irrigation. Reuse for toilet flushing also requires less treatment than other fields of application, thus being the most promising technique for implementation in Kibondemaji.
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Heavy metal reactions with soils with special regard to heavy metals in wastewaters applied to the soil.Tirsch, Franklin S. 01 January 1975 (has links) (PDF)
No description available.
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