前言革制厂排放的污水含有大量的有害物质,如三价铬离子、二价硫离子及有机物等,严重地污染环境和农田,破坏生态平衡和生产。因此,制革的污水必须经过处理才允许排放。目前,处理制革污水的方法有两种,一种是生化处理法;另一种是清浊分流,分别处理法。前者主要是分解二价硫离子,对铬离子仍无法分解掉,只能把含铬离子沉淀物用作树木肥料,但仍不免使铬污染环境和农作物。后者不但能降低排放污水含铬离子量,还能综合利用,化 Preface Wastewater discharged from the mill contains a large amount of harmful substances, such as trivalent chromium ions, divalent sulfur ions and organic compounds, which seriously pollute the environment and farmland and destroy the ecological balance and production. Therefore, tanning wastewater must be treated before it is allowed to discharge. At present, there are two ways to deal with tannery effluent, one is biochemical treatment; the other is clear and turbid shunt, respectively, treatment. The former is mainly the decomposition of sulfide ions, the chromium ions are still unable to break down, only the chromium ion sediment can be used as tree fertilizer, but still can not help chromium pollution of the environment and crops. The latter will not only reduce the discharge of wastewater containing chromium ions, but also the comprehensive utilization of