两种电化学-硫自养集成脱硝工艺的对比

研究了两种电化学 硫自养集成脱硝工艺去除饮用水中的硝酸盐 ,结果表明 ,在同样的条件下 ,当无石灰石反应器的最小电流高于石灰石反应器约 2mA时 ,两种反应器均能取得 90 %以上的NO-3 N去除率 ,并且反应器出水中不存在NO-2 N的积累 .同时 ,无石灰石反应器硫段出水中Ca2 的浓度没有增加 ,避免了出水中的硬度问题 ;而石灰石反应器硫段出水中Ca2 的浓度有所增加 ,造成电化学段的除垢负担 .在同样水力停留时间下 ,无石灰石反应器出水中SO2 -4 的浓度低于石灰石反应器约 1 5mg·l- 1 ;电流高于 3mA时 ,两种反应器出水的pH值均维持在 7左右 .另外 ,无石灰石反应器的出水指标优于石灰石反应器 ,表明在两种集成工艺中 ,硫自养段不填充石灰石的集成工艺优于硫段装填石灰石的集成工艺 .

COMPARISON OF TWO COMBINED ELECTROCHEMICAL AND SULFUR AUTOTROPHIC DENITRIFICATION PROCESSES

Two electrochemical and sulfur combined autotrophic denitrification processes were studied in this paper.The denitrification results of the two combined reactors were compared at different opera tion conditions.It can be concluded from the results that when the minimum current of reactor without limestone was higher about 2 mA than that of the reactor with limestone,the two reactors can both obtained excellent denitrification results under the same operation conditions.The NO - 3 N removal ratios of the two reactors could reach above 90%,and no nitrite was detected in the eff luent. The Ca 2 concentration in the sulfur part effluent of the reactor without limestone was not increased ,which avoided the hardness increase in the effluent.The sulfate concentration in the eff luent of the reactor without limestone was lower than that of the reactor with limestone under the same HRT.When current was higher than 3mA,the effluent pH of two reactors was about neutral.The effluent quality of the reactor without limestone was better than that of the reactor with limestone,which showed that the combined electrochemical and sulfur autotrophic denitrification process without limestone was better than that with limestone.