Driven by excess nutrients in water bodies, eutrophication has long been an issue in water resources management. Harmful algal blooms (HABs) in a highly eutrophic water body lead to hypoxia, creating a “dead zone,” which renders the oxygen levels inadequate for the survival of marine life. This study examined the field-scale filtration performance of two specialty absorbents to improve watershed remediation within a Total Maximum Daily Load program. The goal was to simultaneously remove nutrients and biological pollutants along Canal 23 (C-23) in the St. Lucie River Basin, Florida. The filtration system installed in the C-23 river corridor was equipped with either clay– perlite with sand sorption media (CPS) or zero-valent iron and perlite green environmental media (ZIPGEM). Both media were formulated with varying combinations of sand, clay, perlite, and/or recycled iron based on distinct recipes. Seasonality effects were also evident in nutrient removal efficiencies while the decomposition of dissolved organic nitrogen played a pivotal role in nutrient removal, Overall, ZIPGEM demonstrated a more stable nutrient removal efficiency than CPS in the phase of seasonal changes while biological pollutants can be fully removed over seasons.

Physical-chemical treatment has been shown to be highly successful in treating certain wastewaters and, to some degree, this treatment approach has been promoted as a panacea for all wastewater treatment problems. This project was designed to investigate the best method of treating a wastewater composed primarily of soluble organic material resulting from a cellulose acetate manufacturing process. Both physical-chemical and biological treatment processes were applied to the wastewater to determine whether the performance of the physical-chemical approaches would be less than, equal to, or greater than the performance of the biological treatment system. A further intention of the study was to help in generating guidelines concerning the limitations, if any, of physical-chemical systems. Experimental results showed that chemical treatment using lime or ferric chloride produced only marginal reductions in the COD of the wastewater. From these chemical experiments it was discovered that the wastewater had an extremely high buffering capacity. Adsorption with granular carbon produced a significant reduction in COD provided that a sufficient detention time was allowed. However, final COD values were still too high for discharge under most conditions. In a fairly short aeration period, activated sludge treatment produced an effluent COD value almost one-third the minimum effluent COD value from carbon adsorption. It was therefore concluded that for the wastewater studied t biological treatment was much more efficient than a chemical or physical treatment approach. / Master of Science

A number of investigations have been undertaken with the object of replacing the present water treatment system at the Virginia Polytechnic Institute Power Plant. / Master of Science

Yes / Reverse osmosis (RO) has become a common method for treating wastewater and removing several harmful organic compounds because of its relative ease of use and reduced costs. Chlorophenol is a toxic compound for humans and can readily be found in the wastewater of a wide range of industries. Previous research in this area of work has already provided promising results in respect of the performance of an individual spiral wound RO process for removing chlorophenol from wastewater, but the associated removal rates have stayed stubbornly low. The literature has so far confirmed that the efficiency of eliminating chlorophenol from wastewater using a pilot-scale of an individual spiral wound RO process is around 83 %, compared to 97 % for dimethylphenol. This paper explores the potential of an alternative configuration of two-stage/two-pass RO process for improving such low chlorophenol rejection rates via simulation and optimisation. The operational optimisation carried out is enhanced by constraining the total recovery rate to a realistic value by varying the system operating parameters according to the allowable limits of the process. The results indicate that the proposed configuration has the potential to increase the rejection of chlorophenol by 12.4 % while achieving 40 % total water recovery at an energy consumption of 1.949 kWh/m³.

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.

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.

Constructed wetlands (CWs) originate from natural wetlands and are used for waste water treatment as an alternative to conventional treatment. This thesis was aimed at providing a literary summary of the types of house sewage water treatment plants and constructed wetlands used in the CR and abroad, of their hygienic aspects, functionality, treatment efficiency, expensiveness and the possibilities of their use in the conditions of the CR and their advantages and disadvantages. It also deals with a proposal of a suitable type of house CW for the conditions of the CR and a list of the necessary steps in construction of a house CW. Quite similar systems are being used for house sewage treatment in the Czech Republic and abroad {--} mostly septic tanks, ground mounds, constructed wetlands, active treatment plants and biodiscs. Alternative water treatment methods are generally not suitable for buildings having (now or in the future) the possibility of connection to municipal sewerage systems. They are on the other hand suitable for buildings not connected to sewerage systems or for seasonal objects, remote places and holiday houses with seasonal waste water production. A system with horizontal subsurface flow is mostly used as a CW in the Czech Republic. This CW type ensures sufficient removal of organic contamination and insoluble substances, but the efficiency of nitrogen and phosphorus removal is relatively low. However it is fully sufficient in the instance of low PE numbers, as the loading rate is usually low and the concentration of contaminants in the output water meets the prescribed limits. Foreign researches show that hybrid systems combining horizontal flow with vertical flow and with recirculation are more suitable for improving efficiency of nitrogen removal. Systems with vertical flow and intermittent waste water dosage showing particularly good results in ammoniac removal are also suitable for nitrogen removal. Special materials with higher iron, aluminium or calcium content are most suitable as filling of a constructed wetland or as additional filters or for improvement of phosphorus removal from waste water as they are able to reach efficiency of up to 90 %. In my thesis I came to a conclusion that a CW with horizontal subsurface flow is the most suitable type of house constructed wetland treatment for the conditions in the CR, mainly because it is the most frequently used and thus best proven CW type with sufficient efficiency of treatment for the substances required by standards.

This project developed a model for effective asset management drawn from successful programs in the United States, Australia, and New Zealand. Asset management practices were examined at the City of Ontario Utilities Department; a medium sized utility, and also at the Rainbow Municipal Water District, a small sized utility. Gaps between the ideal model and the existing practices were investigated.

The diploma thesis deals with micro-fuels in drinking water sources and their subsequent removal. In the thesis mainly pesticides and pharmaceuticals are described. The reader is first introduced to the most common pesticides occurring in water and their consumption. Drugs are described in a similar context. In addition, there are practical studies on the occurrence, degradation and removal of micro-pollutants from water. The final thesis is a laboratory experiment dealing with the removal of salicylic acid from water by filtration through the filtration material Bayoxide E33 and activated carbon. The thesis describes the procedure and results of the experiment.