平板型3D-BER去除地下水中硝酸盐氮的优化研究

Optimization research on the removal of nitrate nitrogen from groundwater by flat-plate three-dimensional biofilm electrode reactor

采用平板型三维生物膜电极反应器(3D-BER)对地下水中的硝酸盐氮进行处理,研究了电流强度、进水硝酸盐氮浓度、进水pH和水力停留时间(HRT)等因素对处理效果的影响,结果表明:电流强度为40 mA时,硝酸盐氮被还原的速率最快,且去除率可达到最大值90.15%;进水硝酸盐氮浓度为30 mg/L时,脱氮效果最好,最佳进水pH范围及HRT分别为7~8和12 h.通过正交实验确定反应器的最佳运行工况为电流强度40 mA,进水硝酸盐氮浓度为30 mg/L,进水pH为7,水力停留时间为14 h.

The nitrate nitrogen in groundwater was treated by flat-plate three-dimensional biofilm electrode reactor(3D-BER),and the effects of current intensity,influent nitrate nitrogen concentration,influent pH and hydraulic retention time(HRT)on the treatment effect were studied.The results show that when the current intensity is 40 mA,the reduction rate of nitrate nitrogen is the fastest,and the removal rate can reach the maximum value of 90.15%.When the influent nitrate nitrogen concentration is 30 mg/L,the denitrification effect is the best.The optimum influent pH range and HRT are 7~8 and 12 h respectively.The optimum operating condition of the reactor was determined by orthogonal test as follows:current intensity 40 mA,influent nitrate nitrogen concentration 30 mg/L,influent pH 7,hydraulic retention time 14 h.