The research demonstrated that an easily cultivated fungus was screened from filter materials of fresh water recycle aquaculture system. A fungus, characterized as being able to remediate multiple nitrogenous wastes, was identified as Aspergillus niger NBG5. A. niger NBG5 was developed as superior fungus through bioreactor so as to establish a nitrogenous removal system of single tank stirred tank reactor (SSTR). A. niger NBG5¡¦s remediative responses were tested under various temperatures. The experiment showed that specific nitrogen consumption rate was 0.047 g-N g-cell-1 day-1 at 30¢J which were better than nitrite nitrogen and protein nitrogen consumption. When the artificial wastes¡¦ ammonium concentration was set as 50 mg L-1, its ammonium consumption rate was 4.8 mg m-2 day-1. The ammonium consumption rate reached 0.32 mg m-2 day-1 with aquaculture wastes. The result revealed that SSTR removed nitrogen from aquaculture wastes by A. niger NBG5 and achieved a purpose of decreasing ammonium within aquaculture wastes. The research simulated ammonium variable numerals between SSTR and BSTR (the system of bi-tank stirred tank reactor). Through BSTR, regression formula with water flow rate and ammonium removal efficiency rate was y = 5.7219x-0.9616 when the ammonium concentration was set as 50 mg L-1. SSTR simulated a phenomenon¡Xthe more ammonium concentration aquaculture wastes reached, the much waste water volume of aquaculture tank it had. Based on the same requirements, a better water flow rate would be concluded through various water flow rate simulation tests. SSTR numerical simulation system could simulate ammonium production rate of fish tank to get consumption trends of ammonium concentration in fish tank and reactor. The simulation results would be able to decide later system design, water flow rate, feed timing and similar research references.

Chloride is a deleterious ionic species in cooling water systems because it is important in promoting corrosion. Chloride can be removed from cooling water by precipitation as calcium chloroaluminate using ultra-high lime with aluminum process (UHLA). The research program was conducted to study equilibrium characteristics and kinetics of chloride removal by UHLA process, study interactions between chloride and sulfate or silica, and develop a model for multicomponent removal by UHLA. Kinetics of chloride removal with UHLA was investigated. Chloride removal was found to be fast and therefore, removal kinetics should not be a limitation to applying the UHLA process. Equilibrium characteristics of chloride removal with UHLA were characterized. Good chloride removal was obtained at reasonable ranges of lime and aluminum doses. However, the stoichiometry of chloride removal with UHLA deviated from the theoretical stoichiometry of calcium chloroaluminate precipitation. Equilibrium modeling of experimental data and XRD analysis of precipitated solids indicated that this deviation was due to the formation of other solid phases such as tricalcium hydroxyaluminate and tetracalcium hydroxyaluminate. Effect of pH on chloride removal was characterized. Optimum pH for maximum chloride removal was pH 12 ± 0.2. Results of equilibrium experiments at different temperatures indicated that final chloride concentrations slightly increased when water temperature increased at temperatures below 40oC. However, at temperatures above 40oC, chloride concentration substantially increased with increasing water temperature. An equilibrium model was developed to describe chemical behavior of chloride removal from recycled cooling water using UHLA. Formation of a solid solution of calcium chloroaluminate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate was found to be the best mechanism to describe the chemical behavior of chloride removal with UHLA. Results of experiments that studied interactions between chloride and sulfate indicated that sulfate is preferentially removed over chloride. Final chloride concentration increased with increasing initial sulfate concentration. Silica was found to have only a small effect on chloride removal. The equilibrium model was modified in order to include sulfate and silica reactions along with chloride in UHLA process and it was able to accurately predict the chemical behavior of simultaneous removal of chloride, sulfate, and silica with UHLA.

A indústria têxtil utiliza elevados volumes de água em seus processos, principalmente na etapa de tingimento, em que são utilizadas também quantidades elevadas de corantes e auxiliares têxteis. A presença desses produtos no efluente gera um efeito prejudicial e claramente visível ao ambiente, pois causam alteração nos parâmetros da qualidade da água do corpo receptor. O presente estudo apresenta o pós-tratamento de um efluente têxtil, objetivando o reciclo deste efluente para água de processo de tingimento. Para isso foi utilizada uma combinação de processo físico-químico de coagulação/floculação (CF) e processo de separação por membrana (PSM) de Ultrafiltração (UF) e Osmose Inversa (OI). Os parâmetros analisados antes e após os tratamentos foram: turbidez, condutividade elétrica, demanda química de oxigênio (DQO), carbono orgânico total (COT) e cor. Na etapa de CF foram testados dois tipos de coagulantes, o Sulfato de Alumínio e o Cloreto Férrico, nas concentrações de 30, 50, 70 e 100 mg.L-1. Foram testadas três concentrações de floculante comercial: 0,2, 0,3 e 0,4 mg.L-1. Os experimentos foram conduzidos em pH 7. As etapas de PSM foram conduzidas em módulo plano de Ultrafiltração e em módulos plano e espiral na membrana de Osmose Inversa. O melhor desempenho foi obtido com a dosagem de 50 mg.L-1 do coagulante cloreto férrico e a de 0,3 mg.L-1 de floculante comercial, que apresentou uma redução de 98% na turbidez com relação ao efluente de alimentação. No PSM de Ultrafiltração a remoção de cor não foi satisfatória por ainda apresentar coloração. No PSM de Osmose Inversa com o módulo plano o objetivo da remoção de cor foi atingido com sucesso na análise visual, porém, a vazão de permeado mostrou-se muito baixa inviabilizando o processo. No PSM de Osmose Inversa em módulo espiral a cor foi removida com sucesso, a turbidez ficou abaixo de 1 NTU, a DQO ficou abaixo do limite de detecção do equipamento e a vazão de permeado foi satisfatória. Assim, o estudo aponta como resultado a aplicação CF combinado à OI no tratamento eficaz deste efluente. / The textile industry uses large volumes of water in their processes, especially in the dyeing step, which are also used large quantities of coloring agents and textile auxiliaries. The presence of these products in the effluent generates a harmful effect and clearly visible to the environment because they cause changes in the parameters of the receiving body of water. This paper presents the post-treatment effluent from a textile industry, in order to recycle it as process water for dyeing. A combination of physico-chemical process were carried out applying coagulation / floculation (CF) and Ultrafiltration (UF) membrane separation process (MSP) and reverse osmosis (RO). The parameters analyzed before and after treatments were: turbidity, electrical conductivity, chemical oxygen demand (COD), total organic carbon (TOC) and color. In CF stage two types of coagulants were tested, aluminum sulphate and ferric chloride at concentrations of 30, 50, 70 e 100 mg.L-1. Three concentrations of commercial floculants were evaluated: 0,2, 0,3 e 0,4 mg.L-1. The experiments were conducted at pH 7. MSP steps were conducted in plan Ultrafiltration module, and in the Reverse Osmosis membrane, plan and spiral modules were tested. The best performance was obtained with a dosage of 50 mg.L-1 of the coagulant ferric chloride and 0.3 mg.L-1 commercial flocculant, which showed a 98% reduction in turbidity in respect to the raw effluent. MSP Ultrafiltration color removal was not satisfactory because color was still present. In MSP Reverse Osmosis using the plan module the goal of color removal was successfully achieved in the visual analysis, however, the membrane flow was extremely low compared with the UF permeate flow and prevented the process. The color in MSP Reverse Osmosis spiral module has been successfully removed, the turbidity was below 1 NTU, the COD was below the detection limit of the the equipment and the permeate flow was satisfactory. In this way, the study showed the best application for this effluent is CF combined with RO.

A indústria têxtil utiliza elevados volumes de água em seus processos, principalmente na etapa de tingimento, em que são utilizadas também quantidades elevadas de corantes e auxiliares têxteis. A presença desses produtos no efluente gera um efeito prejudicial e claramente visível ao ambiente, pois causam alteração nos parâmetros da qualidade da água do corpo receptor. O presente estudo apresenta o pós-tratamento de um efluente têxtil, objetivando o reciclo deste efluente para água de processo de tingimento. Para isso foi utilizada uma combinação de processo físico-químico de coagulação/floculação (CF) e processo de separação por membrana (PSM) de Ultrafiltração (UF) e Osmose Inversa (OI). Os parâmetros analisados antes e após os tratamentos foram: turbidez, condutividade elétrica, demanda química de oxigênio (DQO), carbono orgânico total (COT) e cor. Na etapa de CF foram testados dois tipos de coagulantes, o Sulfato de Alumínio e o Cloreto Férrico, nas concentrações de 30, 50, 70 e 100 mg.L-1. Foram testadas três concentrações de floculante comercial: 0,2, 0,3 e 0,4 mg.L-1. Os experimentos foram conduzidos em pH 7. As etapas de PSM foram conduzidas em módulo plano de Ultrafiltração e em módulos plano e espiral na membrana de Osmose Inversa. O melhor desempenho foi obtido com a dosagem de 50 mg.L-1 do coagulante cloreto férrico e a de 0,3 mg.L-1 de floculante comercial, que apresentou uma redução de 98% na turbidez com relação ao efluente de alimentação. No PSM de Ultrafiltração a remoção de cor não foi satisfatória por ainda apresentar coloração. No PSM de Osmose Inversa com o módulo plano o objetivo da remoção de cor foi atingido com sucesso na análise visual, porém, a vazão de permeado mostrou-se muito baixa inviabilizando o processo. No PSM de Osmose Inversa em módulo espiral a cor foi removida com sucesso, a turbidez ficou abaixo de 1 NTU, a DQO ficou abaixo do limite de detecção do equipamento e a vazão de permeado foi satisfatória. Assim, o estudo aponta como resultado a aplicação CF combinado à OI no tratamento eficaz deste efluente. / The textile industry uses large volumes of water in their processes, especially in the dyeing step, which are also used large quantities of coloring agents and textile auxiliaries. The presence of these products in the effluent generates a harmful effect and clearly visible to the environment because they cause changes in the parameters of the receiving body of water. This paper presents the post-treatment effluent from a textile industry, in order to recycle it as process water for dyeing. A combination of physico-chemical process were carried out applying coagulation / floculation (CF) and Ultrafiltration (UF) membrane separation process (MSP) and reverse osmosis (RO). The parameters analyzed before and after treatments were: turbidity, electrical conductivity, chemical oxygen demand (COD), total organic carbon (TOC) and color. In CF stage two types of coagulants were tested, aluminum sulphate and ferric chloride at concentrations of 30, 50, 70 e 100 mg.L-1. Three concentrations of commercial floculants were evaluated: 0,2, 0,3 e 0,4 mg.L-1. The experiments were conducted at pH 7. MSP steps were conducted in plan Ultrafiltration module, and in the Reverse Osmosis membrane, plan and spiral modules were tested. The best performance was obtained with a dosage of 50 mg.L-1 of the coagulant ferric chloride and 0.3 mg.L-1 commercial flocculant, which showed a 98% reduction in turbidity in respect to the raw effluent. MSP Ultrafiltration color removal was not satisfactory because color was still present. In MSP Reverse Osmosis using the plan module the goal of color removal was successfully achieved in the visual analysis, however, the membrane flow was extremely low compared with the UF permeate flow and prevented the process. The color in MSP Reverse Osmosis spiral module has been successfully removed, the turbidity was below 1 NTU, the COD was below the detection limit of the the equipment and the permeate flow was satisfactory. In this way, the study showed the best application for this effluent is CF combined with RO.

A indústria têxtil utiliza elevados volumes de água em seus processos, principalmente na etapa de tingimento, em que são utilizadas também quantidades elevadas de corantes e auxiliares têxteis. A presença desses produtos no efluente gera um efeito prejudicial e claramente visível ao ambiente, pois causam alteração nos parâmetros da qualidade da água do corpo receptor. O presente estudo apresenta o pós-tratamento de um efluente têxtil, objetivando o reciclo deste efluente para água de processo de tingimento. Para isso foi utilizada uma combinação de processo físico-químico de coagulação/floculação (CF) e processo de separação por membrana (PSM) de Ultrafiltração (UF) e Osmose Inversa (OI). Os parâmetros analisados antes e após os tratamentos foram: turbidez, condutividade elétrica, demanda química de oxigênio (DQO), carbono orgânico total (COT) e cor. Na etapa de CF foram testados dois tipos de coagulantes, o Sulfato de Alumínio e o Cloreto Férrico, nas concentrações de 30, 50, 70 e 100 mg.L-1. Foram testadas três concentrações de floculante comercial: 0,2, 0,3 e 0,4 mg.L-1. Os experimentos foram conduzidos em pH 7. As etapas de PSM foram conduzidas em módulo plano de Ultrafiltração e em módulos plano e espiral na membrana de Osmose Inversa. O melhor desempenho foi obtido com a dosagem de 50 mg.L-1 do coagulante cloreto férrico e a de 0,3 mg.L-1 de floculante comercial, que apresentou uma redução de 98% na turbidez com relação ao efluente de alimentação. No PSM de Ultrafiltração a remoção de cor não foi satisfatória por ainda apresentar coloração. No PSM de Osmose Inversa com o módulo plano o objetivo da remoção de cor foi atingido com sucesso na análise visual, porém, a vazão de permeado mostrou-se muito baixa inviabilizando o processo. No PSM de Osmose Inversa em módulo espiral a cor foi removida com sucesso, a turbidez ficou abaixo de 1 NTU, a DQO ficou abaixo do limite de detecção do equipamento e a vazão de permeado foi satisfatória. Assim, o estudo aponta como resultado a aplicação CF combinado à OI no tratamento eficaz deste efluente. / The textile industry uses large volumes of water in their processes, especially in the dyeing step, which are also used large quantities of coloring agents and textile auxiliaries. The presence of these products in the effluent generates a harmful effect and clearly visible to the environment because they cause changes in the parameters of the receiving body of water. This paper presents the post-treatment effluent from a textile industry, in order to recycle it as process water for dyeing. A combination of physico-chemical process were carried out applying coagulation / floculation (CF) and Ultrafiltration (UF) membrane separation process (MSP) and reverse osmosis (RO). The parameters analyzed before and after treatments were: turbidity, electrical conductivity, chemical oxygen demand (COD), total organic carbon (TOC) and color. In CF stage two types of coagulants were tested, aluminum sulphate and ferric chloride at concentrations of 30, 50, 70 e 100 mg.L-1. Three concentrations of commercial floculants were evaluated: 0,2, 0,3 e 0,4 mg.L-1. The experiments were conducted at pH 7. MSP steps were conducted in plan Ultrafiltration module, and in the Reverse Osmosis membrane, plan and spiral modules were tested. The best performance was obtained with a dosage of 50 mg.L-1 of the coagulant ferric chloride and 0.3 mg.L-1 commercial flocculant, which showed a 98% reduction in turbidity in respect to the raw effluent. MSP Ultrafiltration color removal was not satisfactory because color was still present. In MSP Reverse Osmosis using the plan module the goal of color removal was successfully achieved in the visual analysis, however, the membrane flow was extremely low compared with the UF permeate flow and prevented the process. The color in MSP Reverse Osmosis spiral module has been successfully removed, the turbidity was below 1 NTU, the COD was below the detection limit of the the equipment and the permeate flow was satisfactory. In this way, the study showed the best application for this effluent is CF combined with RO.