Estudio comparativo del uso de electrodos de hierro y aluminio en el proceso de electrocoagulación de la vinaza Comparative study of the use of iron and aluminum electrodes in the electrocoagulation process of vinasse

Abstract

In the present study a comparative study between iron and aluminum as electrode materials for the electrocoagulation process of vinasse was carried out, to achieve more efficient separation of solids used as corrosion inhibitors, and color removal as a quality parameter of the process. The stillage is obtained as wastewater from the Argeo Martinez sugar complex in Guantanamo province. It was determined that aluminum electrodes are separated more solids than with iron and less energy consumption obtained. The technical and economic feasible value of the current density was 0.195 A/cm2. With increasing current density results in greater amount of solids in the foam, while the solid that precipitates remains practically constant regardless of the type of electrode material. Pilot tests were conducted to determine the effect of the process variables: density, electrolysis time and pH dissolution in the color removal. With aluminum electrodes had the highest color removal (83,53 %), to: current density 0.159 A/cm2, time 7 min and pH 4.42, resulting the best electrode material. The results showed that aluminium was the most cost-reducing material, yielding an operational cost of $ 87.76 · 10-3 /kg and the energy consumption of 5.625·10-4 kW . h/g of the solids obtaine, while the cost for iron was $ 198.921 · 10-3 /kg and the energy consumption of 8.46 ·10-4 kW . h/g of the solids obtained.