化学沉淀组合电催化氧化处理脱硫废液技术研究

Studies on the Combined Technology of Chemical Precipitation and Electrocatalytic Oxidation for the Pretreatment of Desulfurization Wastewater

真空碳酸钾脱硫工艺碱洗段废液因含有高浓度硫化物、COD等有毒成分而影响焦化废水后续生物处理。以焦化企业实际碱洗段废液为研究对象,选用化学沉淀和电催化氧化的组合方式对其进行预处理。结果表明,室温下当氧化铜的投加量为65 g/L、反应时间60 min时废液中S2-去除率可达93%,且经过高温灼烧可实现Cu O沉淀剂的再生使用。沉淀后出水经电催化氧化处理,在电流10 A、电压4.9 V、电解时间120 min的条件下,出水COD可降至2 400 mg/L,满足常规生化系统进水的要求。

The desulfurization wastewater of caustic cleaning section during vacuum potash desulfurization process is difficult to be biodegraded due to the high concentration of compounds such as sulfide and COD. The combined technology of chemical precipitation and electrocatalytic oxidation is developed to pretreat desulfurization wastewater. The experimental results indicate that the sulfide removing rate can reach 93% when temperature is 25 ℃ and dosage of precipitant is 65 g / L with the reaction time 60 mins,furthermore,the regenerated precipitant at high temperature could be circulated. Then electrocatalytic oxidation is conducted for the precipitated wastewater and under the circumstances of current density 10 A,voltage 4. 9 V,reaction time 120 mins,COD of effluent water quality could be decreased to 2 400 mg / L.