多效电催化氧化技术处理煤层气采出水COD_(Cr)的试验研究

Experimental study on multiple-effect electric catalytic oxidation technology removing COD_(Cr) from coalbed methane produced water

煤层气采出水中COD_(Cr)超标是影响其外排的主要因素。采用多效电催化氧化装置对该废水进行中试处理,得出最佳运行参数为:停留时间1.5 h,运行电流1.5 A。在此条件下运行时,煤层气采出水中COD_(Cr)、F-、Fe2+与S2-的质量浓度分别降低至34.3、8.2、1.5与1.8 mg/L。在最佳条件下运行40 d,装置能连续稳定运行,且处理效果良好,出水中COD_(Cr)、F-与S2-的质量浓度分别低于100、10与1 mg/L,满足GB 8978—1996《污水综合排放标准》一级标准的要求。

Over-standard CODcr concentration in coalbed methane produced water is the main limiting factor of its discharge. A pilot-scale test on the said kind of wastewater treatment by multiple-effect electric catalytic oxidation device was carried out. The optimal operation parameters were determined as follows： the HRT was 1.5 h, the running current was 1.5 A. Under the above condition, the mass concentrations of CODcr F-, Fe2＋ and S2- decreased to 34.3, 8.2, 1.5 and 1.8 mg/L respectively. After a 40-d stable and continuous operation, the mul- tiple-effect electric catalytic oxidation device could still get good performance with mass concentrations of CODcr F- and S2- in effluent water lower than 100, 10 and 1 mg/L respectively, which met the specification for grade 1 in GB 8978-1996 Integrated Wastewater Discharge Standard.