TECHNICAL AND ECONOMIC EVALUATION FOR THE USE OF ELECTROCOAGULATION AT A TANNERY IN BOGOTA-COLOMBIA

摘要

Hexavalent chromium (Cr~(6+)) is used in the leather tanning industry and has been one of the pollutants with the most environmental importance. The removal of this metal in industrial wastewater has been a problem that has been solved in different ways but its treatment is very expensive. This article presents a set of parameters of an electrocoagulation process to determine the optimum operating conditions for the removal of Cr~(6+). For this purpose, an evaluation was conducted on the electrode material, electrode gap spacing, initial pH and residence time. The findings indicated that the combination of aluminum electrodes at a distance of 5 mm with a pH of 8 and a hydraulic retention time of 40 minutes, reached a 98.79% removal. Finally, these variables were validated in water samples taken from a tannery in Bogota where are moval efficiency of 99.75% was obtained. Lastly, the total cost per m~3was calculated for the treatment of an effluent from a tannery.