两步沉淀耦合H_(2)O_(2)氧化深度处理高浓度含氰废水  

Advanced treatment of high-concentration cyanide-containing wastewa⁃ter by two-step precipitation coupled with H_(2)O_(2)oxidation

作　　者：徐文彬 周凯 张艳华 何龙 杨林 XU Wenbin;ZHOU Kai;ZHANG Yanhua;HE Long;YANG Lin(Guangdong Provincial Key Laboratory of R&D for Resource Utilization and Disposal of Hazardous Liquids,Shenzhen 518057,China;Dongjiang Environmental Co.,Ltd.,Shenzhen 518057,China)

机构地区：[1]广东省危险废液资源化与深度处理技术研发企业重点实验室,广东深圳518057 [2]东江环保股份有限公司,广东深圳518057

出　　处：《工业水处理》2023年第2期124-129,共6页Industrial Water Treatment

基　　金：广东省危险废液资源化与深度处理技术研发企业重点实验室项目(2018B030323016)。

摘　　要：为解决广东某电镀厂含氰废水达标排放问题,针对含氰废水中铁氰络合物浓度高的特点,采用两步沉淀耦合H_(2)O_(2)氧化工艺深度处理高浓度含氰废水,重点考察了沉淀剂及H_(2)O_(2)投加量、反应pH等因素对总氰、游离氰、重金属离子去除效果的影响。结果表明,在硫酸亚铁实际投加量与理论投加量之比(质量比)为1.5、反应pH=8,氯化锌实际投加量与理论投加量之比(质量比)为2、反应pH=6时,高浓度含氰废水经硫酸亚铁和氯化锌两步沉淀处理后,废水总氰质量浓度从51400 mg/L降低至1.65 mg/L;两步沉淀处理后的含氰废水进一步经H_(2)O_(2)深度氧化,H_(2)O_(2)实际投加量与理论投加量之比(质量比)为1.8、反应pH=9,处理后总氰质量浓度可降至低于0.5 mg/L,总氰综合去除率接近100%;铜、铬、锌等重金属离子可分别处理至<0.3、<0.5、<1 mg/L,该工艺对重金属离子也具有较好的处理效果,处理后的废水主要指标能够达到《污水综合排放标准》(GB 8978—1996)一级排放标准。In order to solve the problem of standard discharge of high concentration cyanide-containing wastewater in a Guangdong electroplating plant,aiming at the characteristics of high concentration of ferricyanide complex in cyanide-containing wastewater,the advanced treatment technology of two-step precipitation coupled with H_(2)O_(2)oxi⁃dation,was used to treat the wastewater with high concentration of cyanide.The effects of the dosage of precipitant and H_(2)O_(2),pH on the removal effect of total cyanide,free cyanide and heavy metal ions were mainly investigated.The results showed that when the conditions were under the mass ratio of the actual dosage of FeSO_(4)to the theoretical dosage of 1.5 and reaction pH=8,the mass ratio of the actual dosage of ZnCl_(2)to the theoretical dosage of 2 and reac⁃tion pH=6,the mass concentration of total cyanide in wastewater decreased from 51400 mg/L to 1.65 mg/L after the two-step precipitation process using FeSO_(4)and ZnCl_(2)as the precipitant,respectively.Furthermore,the cyanidecontaining wastewater after two-step precipitation treatment was further oxidized by H_(2)O_(2).The mass ratio of the ac⁃tual dosage of H_(2)O_(2)to the theoretical dosage was 1.8,and the reaction pH was 9.After treatment,the mass concen⁃tration of total cyanide could be reduced to less than 0.5 mg/L,and the overall removal rate of total cyanide was nearly 100%.Copper,chromium,zinc could be treated to less than 0.3,0.5,1 mg/L,respectively.Thus,this process also had good treatment effect on heavy metal ions,which could satisfy the first class discharge standard of Inte⁃grated Wastewater Discharge Standard(GB 8978—1996).

关 键 词：两步沉淀 深度处理 铁氰络合物 含氰废水 

分 类 号：X703.1[环境科学与工程—环境工程]