Pós-tratamento físico-químico de efluente de laticínio para remoção de fósforo

Abstract

The increase of dairy industries and their major wastewater generation, rich in nutrients and organic load, arising from the processing of milk also promotes new treatment processes for this wastewater. The use of physical and chemical processes for post-treatment in wastewater treatment plants is proving an attractive alternative, inexpensive and necessary for the implementation of systems for wastewater reuse within the industry itself in order to minimize costs to processes using non-potable water. The aim of the study was the post-treatment of dairy effluents by. Coagulation/flocculation to reduce various forms of phosphorus present as well as evaluating the quality of the effluent seeking a possible reuse. The method consisted of using aluminum polychloride (PAC), aluminum sulfate, and ferric chloride to identify the concentration of each coagulant with greater efficiency for removal of phosphorus and its fractions. Furthermore, we evaluated the removal of Chemical Oxygen Demand, Total Kjeldahl Nitrogen, total suspended solids, color and turbidity of the effluent for reuse. The tests were performed with device "jar test". All applied coagulants achieved good removal rates for the parameters analyzed. The PAC stood out of aluminum sulfate and ferric chloride by presenting efficient removal with low dosages. With the application of 5 mg/L total phosphorus initial PAC has 2 mg/L to 0.70 mg/L. the COD initially presented with a concentration of 88.6 mg / L, with the application of 5 mg/L PAC obtained a final concentration of 12,6 mg/L. With the minimization of organic matter and nutrients such as phosphorus, post-treatment for dairy effluent could contribute to a less impactful dump or reuse one with a high standard of effluent quality