酮连氮法制肼高盐废水离子膜电解前处理工艺

Pretreatment Process of High-salt Wastewater from Production of Hydrazine Hydrate by Ketazine Method for Ion-membrane Electrolysis

采用“两级活性炭吸附-电催化氧化-光催化氧化”工艺处理酮连氮法制水合肼高盐废水,考察了活性炭吸附对后续氧化处理的影响。实验结果表明:两级活性炭吸附通过预去除废水中部分难氧化污染物而大幅缩短后续氧化处理时间,吸附出水依次经电催化氧化和光催化氧化可分别实现深度脱氮和除碳。在各级吸附出水总体积为80 BV、电催化氧化电流密度为50 mA/cm^(2)和反应时间为30 min、光催化氧化反应时间为60 min的条件下,废水TOC和TN去除率分别为99.2%和97.3%。最终处理出水中TOC<10 mg/L,TN<4 mg/L,达到离子膜电解入槽盐水水质要求。

The process of“two-stage activated carbon adsorption-electrocatalytic oxidation-photocatalytic oxidation”was used to treat the high-salt wastewater from production of hydrazine hydrate by ketazine method,and the effect of activated carbon adsorption on subsequent oxidation treatment was investigated.Experimental results showed that two-stage activated carbon adsorption could greatly shorten the oxidation reaction time by pre-removing some of the dysoxidizable pollutants in wastewater,and the adsorbed wastewater underwent electrocatalytic oxidation and photocatalytic oxidation in turn to achieve deep denitrification and carbon removal,respectively.Under the conditions of effluent volume of 80 BV at each adsorption stage,the electrocatalytic oxidation current density of 50 mA/cm^(2) and reaction time of 30 min,and the photocatalytic oxidation reaction time of 60 min,the removal rate of TOC and TN reached 99.2% and 97.0%,respectively.Besides,the final effluent showed TOC<10 mg/L and TN<4 mg/L,which met the water quality requirements of ion-membrane electrolysis.