Optimization of the use of natural coagulants in wastewater treatment using Rotational Central Composite Design ; Otimização do uso de coagulantes naturais no tratamento de efluentes usando Delineamento Composto Central Rotacional

Contamination of water resources by industrial effluents represents a major environmental problem and, in Brazil, the dairy industry is one of the main causes of these problems. The composition of its effluent has a high amount of organic matter and nutrients and, therefore, it is necessary to treat them before disposal. This study aimed to optimize the treatment of synthetic dairy effluents, simulating the coagulation/flocculation process, through the application of a natural coagulant based on Moringa oleifera seed extract, using the Rotational Central Composite Design associated with the Surface Methodology response (MSR). The independent variables in the project were the fast and slow mixing times, the coagulant dosage and the concentration of pollutants. A mathematical model was established with an R² of 0.6, in which the significance of the pollutant concentration and coagulant dosage was proven. From the re-parameterization of the mathematical model, considering only these two variables, an adjustment of 74% was obtained. As a result, a removal efficiency of 94.9% of turbidity was obtained, demonstrating – in the first approximation analysis – a strong result for the use of a natural coagulant to remove turbidity from dairy effluents. ; A contaminação dos recursos hídricos por efluentes industriais representa um grande problema ambiental e, no Brasil, a indústria de laticínios é uma das grandes causadoras desses problemas. A composição de seu efluente possui elevada quantidade de matéria orgânica e nutrientes e, portanto, faz-se necessário tratá-los antes do descarte. Este estudo teve como objetivo otimizar o tratamento de efluentes sintéticos de laticínios, simulando o processo de coagulação/floculação, por meio da aplicação de coagulante natural a base de extrato de semente de Moringa oleífera, utilizando o Delineamento Composto Central Rotacional associado à Metodologia de Superfície de Resposta (MSR). As variáveis independentes no projeto foram os tempos de mistura rápida e lenta, a dosagem de ...