摘要
采用分级沉淀法处理某电镀工业园区的电镀废水。考察了分级沉淀pH、液碱/石灰配比对重金属损失率、污泥量、重金属品位等的影响。在减少污泥量、提高污泥品位等方面对处理工艺进行优化,得到的较优工艺条件为:一级沉淀pH3.0,二级沉淀pH6.5,三级沉淀pH10.5,三级沉淀液碱/石灰乳中石灰乳的体积分数20%。在较优工艺下,铜回收量为0.0682g/L,镍回收量为0.0406g/L,药剂成本为5.49元/t。该工艺在实现废水达标排放的同时,可显著提高污泥品位,促进其资源化。
A multi-stage precipitation method was used to treat the plating wastewater from a plating industrial garden. The effects of pH in individual precipitation stage and the ratio of lime to alkali on the heavy metal loss rate, sludge weight, and metal grade of sludge were studied. The treatment process conditions were optimized with respect to the reduction of sludge weight and the improvement of sludge quality. The optimal process conditions are as follows： pH of first-stage precipitation 3.0, pH of second-stage precipitation 6.5, pH of third-stage precipitation 10.5, and volume fraction of lime milk in third-stage precipitation 20%. Under the optimal process conditions, 0.068 2 g/L copper and 0.040 6 g/L nickel can be reclaimed, and the cost of chemicals used is about 5.49 RMB per ton. The given process not only makes the effluent meet the discharge standard but also significantly improves the sludge grade, promoting the recovery of heavy metals.
出处
《电镀与涂饰》
CAS
CSCD
北大核心
2013年第2期49-51,共3页
Electroplating & Finishing
关键词
电镀废水
铜
镍
分级沉淀
回收
plating wastewater
fractional precipitation
heavy metal
recovery
