焦化废水中氰化物的处理技术研究进展

Advances in the treatment of cyanide in coking wastewater

焦化废水是一种典型的难降解有毒废水,是一种世界公认难处理的工业废水。尤其是焦化废水中的氰化物,具有含量高、毒性大的特点,随意排放会污染水源和农田,造成鱼类的死亡和农作物的减产。因此如何高效价廉地去除焦化废水中的氰化物成为一个值得研究的问题。本文概述了国内外各种去除焦化废水中氰化物的处理方法和应用,主要分为生物法和物理化学法两大类。生物法利用微生物对废水中的污染物进行降解,但是单独使用生物法无法达到排放标准,所以要结合其他方法进行联合处理;简述了碱性氯化法、氰化铁沉淀法、Fenton工艺、活性炭吸附法、臭氧法、离子交换法、二氧化硫与空气法、膜生物反应器(MBR)和膜处理法等物理化学方法各自的优缺点,并提出了今后的发展方向;以期达到高效低耗处理焦化废水中氰化物的目的。

Coking wastewater is a kind of typical toxic wastewater which is difficult to be degraded,and it is recognized as a kind of refractory industrial wastewater in the world.In particular,the cyanide in coking wastewater has the characteristics of high content and high toxicity.If discharged randomly,it will pollute the water source and farmland,resulting in the death of fish and the reduction of crop production.Therefore,how to remove cyanide from coking wastewater efficiently and cheaply has become a problem worthy of consideration and research.This paper summarizes various treatment methods of cyanide from coking wastewater and their application,which are mainly divided into two categories:biological methods and physicochemical methods.Biological method is the use of microorganisms to degrade pollutants in wastewater,but the single use of biological method cannot meet the discharge standard,so biological method should be combined with other methods for joint treatment.Physical and chemical methods,such as alkaline chlorination,ferric cyanide precipitation,Fenton process,activated carbon adsorption,ozonation,ion exchange method,sulfur dioxide and air method,MBR and membrane treatment,have their own advantages and disadvantages.This paper briefly introduces and analyzes the principle and application of the current treatment methods,and the development suggestion of joint treatment is put forward. It is hoped that it can be helpful for the treatment of cyanide in coking wastewater.