APLICA O DO PLANEJAMENTO EXPERIMENTAL NO MéTODO DE ELETRO-COAGULA O PARA A REMO O DE MATéRIA ORG NICA DE EFLUENTES FRIGORíFICOS

In this work an optimized electro-coagulation process was applied on the food-processingindustrial effluent treatment in order to reduce the high organic load. A lab-scale electro-coagulation reactorconsisting of a set of six equidistant aluminum plates within a 1 L container was built and its performancedepending on three important variables: effluent initial pH, electrolyze time and electric current was alsoevaluated on the basis of the Response Surface Methodology. A 33 factorial design on the EC experimentswas performed, optimizing the reactor operating variables according to the best response of chemical oxygendemand (COD), color and turbidity removals. Second-order models representing the response variableswere validated by ANOVA. The reactor optimal performance was achieved at 52.5 min electrolysis time, 4A electric current and 5 initial pH. Under these conditions 87% COD, 94% color, and 98% turbidity wereremoved. The EC treatment of food-processing industrial effluent proved to provide a cost-effective thanthe conventional one, indicating clearly that the method of electro-coagulation is very promising alternativefor industrial applications