Abstract:Fenton preoxidation neutralization, arsenic removal method was used to purify arsenic and iron containing metallurgical wastewater. Effects of Fenton oxidant dosage and oxidation time on iron oxidation rate and effects of reagent dosage, reaction time, mixing speed and reaction temperature on arsenic removal were studied through single factor test. The obtained optimum conditions of arsenic removal solution and neutralization slag were compared with the enterprise process parameters. The results show that Fe2+ concentration in wastewater drops from 2.23 g/L to 0.01 g/L with oxidation rate of Fe2+ of 99.55% after adding 5 mL/L hydrogen peroxide (30%) to wastewater for preoxidation for 5 min. Arsenic removal rate is 99.9% under the optimum conditions for arsenic removal include lime dosage 15 g/L, stirring rate of 300 r/min, temperature of 30 ℃, and reaction time of 50 min. The toxic leaching test result of neutralization residue is 0.32 mg/L, which meets the Identification Standard for Hazardous Waste Leaching Toxicity (GB 5085.3—2007), and realizes the harmless treatment of arsenic.