A racionalização dos recursos hídricos tem sido uma das metas das indústrias em vários setores. Tais metas exigem inovações tecnológicas tanto para novos processos produtivos quanto para novas técnicas de tratamento e reutilização de água na cadeia de produção. Os custos elevados de água industrial no Brasil, particularmente nas regiões metropolitanas, têm estimulado as indústrias nacionais a avaliar as possibilidades de reúso. O objetivo deste trabalho é a aplicação do tratamento de águas de processo contendo polipropileno utilizando radiação ultravioleta e peróxido de hidrogênio, isto é, o sistema UV/H2O2, visando adequá-las para reúso no próprio processo, reduzindo a necessidade de captação de água pré-tratada e de descarte de efluente. A primeira parte do estudo consistiu na realização de experimentos em um sistema fotoquímico de batelada, empregando quatro diferentes correntes efluentes de processo, para a avaliação da viabilidade técnico-econômica do tratamento fotoquímico, bem como para a obtenção de dados referentes à cinética das reações fotoquímicas. Com base nas informações obtidas, na segunda parte do estudo foram realizados experimentos em um sistema fotoquímico contínuo, a fim de obter dados para o aumento de escala para aplicação industrial do processo de tratamento contínuo. Os resultados experimentais indicaram a viabilidade técnica de aplicação do sistema UV/H2O2 utilizando fonte de luz artificial para todas as correntes de processo estudadas, tendo sido alcançados níveis de remoção de matéria orgânica acima de 90%. No entanto, sob o ponto de vista econômico, apenas as correntes com baixo teor de carbono orgânico total dissolvido (COT), entre 6 e 12 mgC L-1, mostraram-se adequadas ao reúso, após o tratamento. / Rationalization of water use has been one of the goals in many industrial activities, and, in particular, in the petrochemical industry. Such goals demand technological innovations in the productive processes and in techniques for treatment and reuse of water in the production chain. The high costs of industrial water, particularly in some metropolitan regions, have stimulated the industries to evaluate the possibilities of water reuse. The objective of this work is to evaluate the feasibility of the UV/H2O2 photochemical process applied to the treatment of process waste water containing polypropylene, aiming at the reuse of the waste water in the as process water in the industrial complex, thus reducing the need for tap water supply and waste water generation rate. The first part of this study consisted of laboratory-scale experiments in a batch photochemical reactor with four different waste water streams to perform the technical and economical feasibility of the photochemical treatment, as well to obtain data on the degradation rate. Based on the results of the first part, the second part of this study consisted of experiments in a continuous photochemical reactor, aimed at obtaining experimental data for reactor scale-up. Experimental results indicate that the UV/H2O2 photodegradation process is able to remove more than 90% of the organic compounds contained in the waste water. However, only waste waters containing relatively low contaminant levels (between 6 and 12 mgC L-1) can be treated at economically favourable costs.

Foi pesquisada a aplicação de métodos, em nível de laboratório, através dos quais é possível otimizar, tratar e dispor resíduos de lavagem de filtros de estações de tratamento de água (Caso ETA do rio Descoberto - ETA-RD Brasília). Na clarificação da água de lavagem dos filtros, observou-se o efeito favorável da adição de polímero para melhorar a separação líquido-sólido é, portanto, as eficiências de remoção de turbidez, cor aparente, sólidos suspensos e coliformes totais. Observou-se melhor sedimentabilidade do lodo a ser desaguado. Os ensaios de centrifugação, em escala de bancada, mostraram que o método aplicado auxilia na determinação da dosagem a ser usada numa centrífuga em escala real. Foram avaliados três métodos de disposição do lodo adensado da ETA-RD em ETE: 1) sedimentação com esgoto sanitário e posterior digestão anaeróbia do lodo; 2) Digestão anaeróbia e 3) digestão aeróbia. Os melhores resultados foram obtidos com a digestão anaeróbia. Os estudos realizados mostraram que há diversas alternativas de tratamento e disposição desses resíduos, mas é necessário, sempre que possível, a avaliação das diferentes alternativas para selecionar a(s) mais apropriada(s) a cada caso em particular, pois fatores como custos e disponibilidade de de sistemas ou equipamentos, definirão a aplicabilidade ou não de determinado método. / It was researched the application of methods on laboratory bench scale to optimize the reuse, treatment and disposal of wastes from filter backwash of Water Treatment Plant - WTP (WTP-RD Descoberto River, Brasília case). In the clarification process of this waste, favorable effect of addition of polymer for best liquid-solid separation and, thus, better removal efficiencies of turbidity, apparent color, suspended solids and total coliforms was observed. Better sedimentability of the sludge occurred. The centrifugation tests showed that the applied method help on determination of dosagem to be used in full scale. Three methods to dispose thickened sludge of WTP-RD on wastewater treatment Plants - WWTP were evaluated: 1) Sedimentation with domestic sewage and anaerobic digestion of sludge; 2) Anaerobic digestion and 3) Aerobic digestion. Best results were obtained with anaerobic digestion. The results showed that there are alternatives of treatment and disposal of wastes of WTP, but is necessary, if possible, to make the evaluation of this alternatives to select the most appropriate(s) in each case because factors as costs, systems or equipments availability, will define the applicability or not of a particular method.

Foi pesquisada a aplicação de métodos, em nível de laboratório, através dos quais é possível otimizar, tratar e dispor resíduos de lavagem de filtros de estações de tratamento de água (Caso ETA do rio Descoberto - ETA-RD Brasília). Na clarificação da água de lavagem dos filtros, observou-se o efeito favorável da adição de polímero para melhorar a separação líquido-sólido é, portanto, as eficiências de remoção de turbidez, cor aparente, sólidos suspensos e coliformes totais. Observou-se melhor sedimentabilidade do lodo a ser desaguado. Os ensaios de centrifugação, em escala de bancada, mostraram que o método aplicado auxilia na determinação da dosagem a ser usada numa centrífuga em escala real. Foram avaliados três métodos de disposição do lodo adensado da ETA-RD em ETE: 1) sedimentação com esgoto sanitário e posterior digestão anaeróbia do lodo; 2) Digestão anaeróbia e 3) digestão aeróbia. Os melhores resultados foram obtidos com a digestão anaeróbia. Os estudos realizados mostraram que há diversas alternativas de tratamento e disposição desses resíduos, mas é necessário, sempre que possível, a avaliação das diferentes alternativas para selecionar a(s) mais apropriada(s) a cada caso em particular, pois fatores como custos e disponibilidade de de sistemas ou equipamentos, definirão a aplicabilidade ou não de determinado método. / It was researched the application of methods on laboratory bench scale to optimize the reuse, treatment and disposal of wastes from filter backwash of Water Treatment Plant - WTP (WTP-RD Descoberto River, Brasília case). In the clarification process of this waste, favorable effect of addition of polymer for best liquid-solid separation and, thus, better removal efficiencies of turbidity, apparent color, suspended solids and total coliforms was observed. Better sedimentability of the sludge occurred. The centrifugation tests showed that the applied method help on determination of dosagem to be used in full scale. Three methods to dispose thickened sludge of WTP-RD on wastewater treatment Plants - WWTP were evaluated: 1) Sedimentation with domestic sewage and anaerobic digestion of sludge; 2) Anaerobic digestion and 3) Aerobic digestion. Best results were obtained with anaerobic digestion. The results showed that there are alternatives of treatment and disposal of wastes of WTP, but is necessary, if possible, to make the evaluation of this alternatives to select the most appropriate(s) in each case because factors as costs, systems or equipments availability, will define the applicability or not of a particular method.

The process of allocating necessary resources like clean water, fuel/energy and food have resulted in an unsustainable use of natural resources causing problems with Soil erosion, soil fertility, desertification, deforestation, eutrophication and global warming. The purpose of this study was to gain information on the functional design of a waste management system enabling the organic components of domestic waste to be processed as useful resources while at the same time allow them to be re-circulated. The main part of this study was carried out at the Kendu SDA Hospital in the Rachyonyo district in western Kenya. For the case of this study two main objectives where chosen. The first was to develop a principal technological solution using three classed “appropriate technologies” found suitable for the purpose namely biogas, ecological water treatment systems and slow sand filtration. The second was to further analyse each included technology to further develop their potential to fit the concept. Results from the pilot facilities where then to be retrieved from the actual component selection and construction process itself, with performance analysis left for future studies. The main purpose of the biogas system study has been to evaluate the original ideas of overall concept, details, materials and construction methods. The 1 m3 biogas system has improved significantly during the development process and is today not far from an implementation, i.e. construction on a slightly larger scale. The biogas system developed during the project has proven to have potential for digestion of both latrine and kitchen waste. Using the two as fuel for the process does not only remove a problem – it grants several benefits. The ecological waste water treatment system main objective was to design and construct a pilot SSF-wetland. Results show that the construction process for smaller scaled SSF systems is simple and does not require trained personnel or specialized equipment and that significant cost reduction can be made by using locally available materials. The slow sand filtration sub system concept is called PT SCX and though still in the stage of development proved to have great potential concerning both efficiency and sustainability. The PT SCX comprises the advantages of slow sand filtration with further development of individual system solutions. It was adapted to enable both integration to the IWESS solution and stand alone installations purifying even highly turbid surface water sources to drinking water quality. The result from the study confirms the suitability of the three included technologies, ecological waste water treatment, biogas and slow sand filtration to work in an integrated system called IWESS- Integrated Water Energy and Sanitation Solution. The combined subsystems can together with source separated sewage offer full resource recovery enabling recirculation of both nutrients and water. In addition the system can be designed as a net producer of renewable and emission free energy.

<p>The process of allocating necessary resources like clean water, fuel/energy and food have resulted in an unsustainable use of natural resources causing problems with Soil erosion, soil fertility, desertification, deforestation, eutrophication and global warming. The purpose of this study was to gain information on the functional design of a waste management system enabling the organic components of domestic waste to be processed as useful resources while at the same time allow them to be re-circulated. The main part of this study was carried out at the Kendu SDA Hospital in the Rachyonyo district in western Kenya. For the case of this study two main objectives where chosen. The first was to develop a principal technological solution using three classed “appropriate technologies” found suitable for the purpose namely biogas, ecological water treatment systems and slow sand filtration. The second was to further analyse each included technology to further develop their potential to fit the concept. Results from the pilot facilities where then to be retrieved from the actual component selection and construction process itself, with performance analysis left for future studies.</p><p>The main purpose of the biogas system study has been to evaluate the original ideas of overall concept, details, materials and construction methods. The 1 m3 biogas system has improved significantly during the development process and is today not far from an implementation, i.e. construction on a slightly larger scale. The biogas system developed during the project has proven to have potential for digestion of both latrine and kitchen waste. Using the two as fuel for the process does not only remove a problem – it grants several benefits.</p><p>The ecological waste water treatment system main objective was to design and construct a pilot SSF-wetland. Results show that the construction process for smaller scaled SSF systems is simple and does not require trained personnel or specialized equipment and that significant cost reduction can be made by using locally available materials.</p><p>The slow sand filtration sub system concept is called PT SCX and though still in the stage of development proved to have great potential concerning both efficiency and sustainability. The PT SCX comprises the advantages of slow sand filtration with further development of individual system solutions. It was adapted to enable both integration to the IWESS solution and stand alone installations purifying even highly turbid surface water sources to drinking water quality.</p><p>The result from the study confirms the suitability of the three included technologies, ecological waste water treatment, biogas and slow sand filtration to work in an integrated system called IWESS- Integrated Water Energy and Sanitation Solution. The combined subsystems can together with source separated sewage offer full resource recovery enabling recirculation of both nutrients and water. In addition the system can be designed as a net producer of renewable and emission free energy.</p>

From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / Sewage effluent for irrigation is well established. This study determines the capacity of selective turfgrass-soil systems to purify municipal sewage effluent and to measure the degree of utilization of nitrogen in the effluent by turfgrass. Chlorinated secondarily treated sewage effluent from the city of Tucson was applied to turfgrass grown on sandy loam, silt and loam, under three levels of irrigation under laboratory conditions of duplicate pots. Each pot had 2 suction probes to estimate soil moisture tensions and to allow soil water sampling. The study operated from September to March, 1972, for 30 weeks. Purification efficiency, nitrogen utilization and percent recharge were calculated. Turfgrass can be irrigated with sewage effluent at common rates without hazard of nitrogen pollution to groundwater. Purification efficiency exceeded 90 percent for all irrigation levels on sandy loam and silt. Nitrogen utilization was greater over sandy loam. Turfgrass-soil systems can utilize nitrogen and purify waste water.

This study took place in Malawi, south eastern Africa. Metal contamination of water and soil is a threat to the environment and human health and is a serious concern in many countries including Malawi. Blantyre is the city of commerce where most of the industry is located along the banks of the main rivers. Some of the industries produce wastewater, which due to poor access to wastewater treatment plants, is discharged without treatment into the environment. A match factory in Blantyre uses chromium as a colouring agent for match heads and very high concentrations of chromium(VI) have been measured downstream the factory with concentrations up to 56 mg/l, which is much higher than the WHO guidelines of 0.05 mg/l.  Chromium(VI) mainly occurs as chromate CrO42- and dichromate Cr2O72- ions. They are both toxic and carcinogenic and can cause mutations and chromosomal aberrations.   The aim of the study was to evaluate the efficiency of Granular Ferric Hydroxide (GFH) in adsorbing and removing chromium from an aqueous phase. Wastewater was collected from the match factory and by optimizing relevant parameters the removal efficiency was maximized. The parameters optimized were pH, dosage and contact time and the effect of initial concentration. After respective experiment, all samples were analysed for chromium using microwave plasma atomic emission spectroscopy (MP-AES).   The optimum pH was chosen to 8.0, the dosage to 17.4 g GFH/l and the contact time to 2 hours for a 95% removal of total chromium in undiluted wastewater. The removal efficiency of the GFH was 2.84 mg Cr/g GFH. To implement wastewater purification with GFH a number of practical issues have to be taken into consideration. Above all, a sufficient stirring method has to be devised as the removal efficiency is much affected by improper stirring. / Denna studie genomfördes i Malawi, sydöstra Afrika. Metallföroreningar i vatten och mark är ett stort problem i många länder, inklusive Malawi. Landets centrum för industri och handel ligger i Blantyre där de flesta av industrierna ligger längs med floderna. En del industrier genererar utsläppsvatten och på grund av dålig tillgång till vattenreningsteknik och vattenreningsanläggningar släpps mycket av det förorenade vattnet obehandlat ut i naturen. En tändsticksfabrik i Blantyre använder kromsalter för att färga tändstickshuvudena röda och höga koncentrationer av sexvärt krom har uppmätts nedströms fabriken. De uppmätta koncentrationerna var upp till 56 mg/l vilket är betydligt högre än WHO:s riktvärde på 0,05 mg/l. Sexvärt krom förekommer som kromat CrO42- och dikromat Cr2O72- joner vilka båda är mycket toxiska och cancerframkallande och därmed ett hot mot miljö och människor. Syftet med studien var att undersöka om granulära järnoxider (GFH) kunde användas som en adsorbent för att rena utsläppsvatten från kromater. Utsläppsvatten hämtades från tändsticksfabriken och genom att optimera relevanta parametrar kunde GFHns adsorbtionseffektivitet maximeras. Parametrarna som optimerades var pH, dos, kontakttid och initialkoncentration. Efter respektive experiment mättes kromkoncentrationen med mikrovågsplasma atomemissionsspektroskopi (MP-AES) Det optimala pH-värdet valdes till 8.0, dosen till 17.4 g GFH/l med en kontakttid på 2 timmar för en 95.3% reningsgrad på outspätt utsläppsvatten. Adsorptionseffektiviteten på GFHn var 2.84 mg Cr/g GFH. För att implementera vattenrening med GFH behöver flera praktiska aspekter tas med i beaktning. Framförallt är det viktigt med en bra omrörning för att GFHn ska kunna adsorbera effektivt.

From the Proceedings of the 1975 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 11-12, 1975, Tempe, Arizona / In direct (normal, forward) osmosis water automatically flows through a semipermeable membrane from a "source" solution of low concentration to a "driving" solution with higher solute content. The process requires a membrane which is impermeable to the solutes; hydrostatic pressure differences are not directly involved and can be set equal to zero. In principle, direct osmosis is a low -technology, low-power consumption method for reducing the water volume of industrial effluents or liquid agricultural products, and for reclaiming brackish irrigation water. In the latter application the driving solution may utilize fertilizer as a solute; the source solution is drainage that contains harmful salt components. This type of operation has been experimentally demonstrated. This paper summarizes basic physical principles and introduces some quantitative design factors which must be understood on both a fundamental and on an applications level.

From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / This study investigated the potential of a soil-turf filter to renovate secondary effluent applied in excess of consumptive use. Lysimeter plots were filled with a sand and a sand mix, and seeded to winter ryegrass. In spring, plots were scalped and seeded to bermudagrass. Plots were drip irrigated twice a week with secondary effluent at rates of 10, 17, 22, 34, and 43 mm/day. Leachate and effluent were analyzed for NH -N, NO,-N, and organic-N. Grass clippings were oven dried, weighed, and analyzed for organic -N. Percent of leachate available for groundwater recharge was 50% at the lowest rate and 68% at the highest rate when values were averaged for both soils. The amount of nitrogen removed by the soil-turf filter using sand was 42 to 87% and 52 to 90% on the mix, decreasing as application rate increased. The highest nitrogen removal and utilization occurred at the lowest application rate. Turf utilization of nitrogen was 10 to 28% on sand and 18 to 36% on mix, decreasing as rate of application increased. The sand-turf filter renovated 22 mm/day and the mix-turf filter renovated 43 mm/day, yielding leachate averaging less than 10 ppm NO₃-N.

From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / As a part of the ongoing Phoenix Urban Study, Federal legislation mandates that land treatment of wastewater be seriously considered as a treatment option. Land treatment is a particularly viable alternative in the Phoenix area because in this arid desert climate, all water is a scarce and valuable resource and land treatment offers a positive opportunity for the conservation of this resource. In addition, land treatment systems are generally less expensive and have lower energy requirements than other conventional treatment processes while resulting in comparable treatment. The analysis of wastewater treatment systems for populated urban areas necessitates the preliminary investigation and comparison of a large number of alternatives to allow for a realistic engineering and economic evaluation. The site specific nature of land application adds additional variables that must be considered. A preliminary systems approach indicated that to minimize the effect of a human judgement factor between sites and yet maximize the depth of the initial analysis, computer techniques should be utilized for analysis and data storage. A summary of this analysis with appropriate cost, power usage, land requirements and other pertinent factors will be presented.