焦化废水中氰化物检测方法研究

STUDY ON THE DETECTION METHOD OF CYANIDE IN COKING WASTEWATER

焦化废水又称酚氰废水,属于难降解有毒有害污水,从生态环境和人类生存环境方面考虑,都应对焦化废水的排放有严格的指标控制要求,尤其是处理后废水中剧毒氰化物的残留含量更要严格控制。通过一系列的试验研究,对氰化物的检测从取样到分析步骤都给出了更明确的条件和依据,焦化废水样应该用黑色瓶采集,现场直接加入NaOH固定,使其p H值在12. 0～12. 5之间,避光保存,并立即分析。氰化物极不稳定,采样固定后应在4℃以下保存,并在24 h内完成分析。

Coking wastewater, also named as phenol-cyanogen wastewater, is a refractory toxic wastewater. No matter for ecological environment or the living environment for human being, strict index control requirements should be made for the coking wastewater discharge. Especially for the residual content of highly toxic cyanide in wastewater should be more strictly controlled. Through a series of experimental studies, the cyanide detection from sampling to analysis procedures is given more clear conditions and basis. Thus, coking wastewater samples should be collected in a black bottle, and the NaOH fixed is directly added in site, so that its pH value is between 12.0~12.5, keep in dark place, and be analyzed immediately. Cyanide is extremely unstable, so it should be kept below 4 degrees and analyzed in 24 h after sampling and fixing.