An investigation on treatment of tannery wastewater by electrocoagulation

Treatability by the electro-coagulation (EC) and electro-Fenton (EF) methods have been
applied to the tannery wastewater from an organized industrial region consisting mostly of
tannery plants and compared with each other in this study. Iron plates were used as the
anode and cathode. Electrical current was applied at a value of 33.3 mA m-2 for all processes
in order to determine the electricity consumptions for chemical oxygen demand (COD) and
sulfide removal. The optimal contact duration for each process was discovered at the end of
the first five minutes. During the EC process, the removal efficiencies of COD and sulfide
were 46% and 90%, respectively. Electricity consumptions were also obtained as 1.8 kWh kg-
1 COD removed and 27.7 kWh kg-1 sulfide removed. During the EF process, on the other
hand, the removal efficiencies of COD and sulfide parameters were 54% and 85%,
respectively, and electricity consumptions were also obtained as 1.5 kWh kg-1 COD removed
and 8.3 kWh kg-1 sulfide removed. Furthermore, the removal efficiencies of total Chrome and
suspended solids were determined to be 97% and 70%, respectively.