为了探讨曝气生物滤池(BAF)对氰化物的去除能力,采用两级曝气生物滤池对含氰废水进行了启动研究.结果表明,当BAF1和BAF2的HRT分别为7h和5h、进水温度为20～25℃、气水比为10:1、进水COD为400 mg/L左右(葡萄糖配水)时,随着进水CN-的增加,两级BAF对CN-、COD和TN的去除率逐渐下降.当进水CN-从20.22 mg/L增加到65.23 mg/L时,两级BAF对CN-、COD和TN的去除率相应从92.1％、90.2％和61.7％降至59.1％、53％和25.4％.当初始CN-低于35.34 mg/L时,经过24 h闷曝后,BAF对CN-的去除率可达99％以上,出水CN-R于0.2 mg/L.初始CN-越高,BAF对CN-的降解速率越慢,完全降解CN-所需的时间越长.%To investigate the capacity of cyanide removal by biological aerated filteT (BAF), two-stage BAF was used for treating cyanide wastewater in its start-up test. The results show that the removal rate of CN-、 COD and TN in two-stage BAF decreased with the influent CN- increasing, under the condition of HRT of 7h in BAF1 and 5 h in BAF2, influent temperature of 20-25 ℃, air-water ratio of 10 : 1, influent COD of 400mg/L (containing glucose). When influent CN~ increased from 20.22 mg/L up to 65.23 mg/L, the removal rate of CN-、 COD and TN were decreased from 92.1%, 90.2% and 61.7% down to 59.1%, 53% and 25.4%, respectively. BAF can get higher than 99% removal rate of CN- by 24 h reaction with initial CN- less than 35.34 mg/L. Degradation rate of cyanide in BAF decreased with higher initial cyanide concentration, and more time is needed in BAF to degrade cyanide completely.
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