Coagulantes naturais e coagulante químico para o tratamento de efluente de indústria de café solúvel

Abstract

Holding one third of the worldwide production of coffee and being a major center consumer of these grains, Brazil concentrates major industries of the soluble coffee business. Given the scarcity and environmental awareness, it is necessary to treat the wastewater of this industry, so that it can return to the cycle without compromising the environment and water bodies, checking new possibilities that will follow the tendency of using products with concern for the environment and sustainability. Thereunto, the present study aimed to compare the efficiency of application of natural coagulants Moringa Oleifera, Tanfloc SG and okra associated with ferric chloride (OFC) and the chemical coagulant ferric chloride in the treatment of effluents of the soluble coffee industry in the coagulation process, flocculation and sedimentation. To optimize the data, it has been used the experimental design Composite Rotational Design (RCCD), in which were considered as independent variables the concentration and time, and as dependent variables the analyzed parameters were apparent color, chemical oxygen demand (COD), electrical conductivity, pH and series of solids. Unless the Moringa oleifera, the treatments with the natural coagulant Tanfloc SG presented results as good as when using the chemical coagulant ferric chloride. The Tanfloc SG coagulant owns the highest color removal and COD, with 50.5% and 27.9%, respectively, besides presenting a significant removal of volatile solids (78.48%). The association of okra to the ferric chloride becomes a viable alternative since the efficiency of reduction parameters COD (27.9%) and total solids (61.1%) were superior to the use of ferric chloride only. In general, natural coagulants Tanfloc SG and okra associated with ferric chloride become a viable option to the treatment.