Electrocoagulation and the Fenton reagent processes were explored to treat the dye manufacturing shop wastewater.In the case of electrocoagulation

for iron anode

20.54% of COD removal efficiency was achieved at the optimum current density of 12.5 mA/cm2

while for aluminum anode

37.57% of COD was removed at the optimum current density of 8.33 mA/cm2.The removal efficiency of COD with Fenton reagent was investigated at various effect factors.74.62% of COD was removed and the reagent costs were 39.1 yuan per ton COD.The optimum operation parameters were as follows: 600 mg/L FeSO4·7H2O

6 mL/L H2O2(30%)

pH 2.21

90min reaction time.The results indicate that elctrocoagulation with aluminum anode is more effective than that of with iron

while Fenton reagent is better than elctrocoagulation for its high efficiency and low cost.