含氟污水返回过磷酸钙生产系统再利用

为使过磷酸钙副产氟硅酸钠的生产过程中所产生的含氟污水达标排放,南化公司采用了两种处理方法.一种是化学处理,将含氟污水与熟石灰水反应,氟会生成氟化钙沉淀,氟化钙和污水的硅胶经压滤去除;但每年需水处理费50万元左右,年累计产生3000t废渣需外运堆放,产生二次污染.另一种是含氟污水返回过磷酸钙生产系统,用作原料硫酸的稀释水,无二次污染,不仅改善了过磷酸钙的物性,减少防结块剂的用量,而且还降低了硫酸消耗,每年可降低过磷酸钙生产成本240万元;但需解决部分管道、设备的防腐问题.

Recycling the fluoride-containing waste water to SSP production system

In order to accord with the national discharge standard of waste water in the SSP production,two kinds of treating methods are used by the enterprise.One is chemical treatment,the fluorine sewage reacts with slaked lime water to be settled down as calcium fluoride,the calcium fluoride and sewage silica gel are removed by pressurized filtering.The water treatment cost is about 0.5 million RMB Yuan per year,there are about 3kt waste residue needed to be transported towards outside and stacked every year,and the second time pollution is caused.The other method is that fluorine sewage return to the SSP production system as diluting water of sulfuric acid,and there is no second pollution.This method not only improves SSP nature and reduces the amount of anti-caking agent,but also reduces the consumption of sulfuric acid.About 2.4 million RMB Yuan of SSP production will be cut down every year.However,the anticorrosion of some pipes and equipments should be solved.