Electrocoagulation Treatment for Wastewaters from some Restaurants in New Damietta City-Egypt

Abstract

The current investigation entails the application of an electrocoagulation treatment process to the kitchens’ wastewaters discharged from five of the most popular restaurants in New Damietta city – Egypt. The electrocoagulation process was carried out using aluminum electrodes at variable electrolysis times. The specifications of the applied system were; pH 7.03, temperature 25oc, distance between the two used electrodes 20 mm, the applied current 1 ampere, voltage 20 volt, current density 40 mA/cm2, plate shape of the electrode, and dimensions of 100 mm x 50 mm x 0.095 mm, with a surface area of 25 cm2 for each electrode. The system was investigated to treat the food processing effluents of the restaurants prior to their discharge to the public sanitary network, in order to comply with the Egyptian Environmental Regulation (Decree 44/2000) of the wastewaters discharged to the public sewer system. Total operating cost including the energy and electrode consumption, and theoretical amount of hydrogen gas produced were calculated. The results revealed good removal efficiency percentages, especially for the removal of organic matters. The COD removal efficiency for the restaurants 1, 2, 3, 4 and 5 were 84.6, 74.5, 89.15, 68.5, and 92.79%, respectively. At the same time, oil & grease was almost fully removed from the wastewater of the restaurants 1 and 2, while restaurants 3, 4, and 5 had a very good removal efficiency percentage of 92.42, 94.5, and 87.76%, respectively.