石英砂诱导结晶处理含Hg^(2+)废水

Treatment of Hg^(2+) wastewater by quartz sand induced crystallization

以含Hg^(2+)配水为对象,以Na_2S·9H_2O为沉淀剂,获得无载体时Hg^(2+)最佳去除条件;在此条件下,对比天然石英砂、精制石英砂、分析纯石英砂的诱导效果,从中选出最佳载体;采用选出的最佳载体开展工业废水诱导结晶试验。结果表明,不加载体最佳沉淀条件为:p H为8.5,加药比为10倍,反应平衡时间约13 min;添加的载体均在热力学上促进沉淀反应,同时精致石英砂还在动力学上促进沉淀反应,为最佳载体。精制石英砂在未处理混合废水、厂方已处理废水搅拌沉淀试验中,Hg^(2+)去除效率分别为98.54%、99.20%,原水处理效果略低于配水,同时浊度增加。

With Hg^（2＋） containing water as the object,the optimal removal conditions without carrier are achieved by using Na_2S·9H_2O as precipitant： 8. 5 of p H,more than 10 times of dosage and about 13 minutes of reaction equilibrium time. Under this condition,the induced crystallization effects are compared by using natural quartz sand,refined quartz sand and pure quartz sand as carriers. The optimal carrier is then selected for industrial wastewater induced crystallization test. The results show that the addition of carrier can all promote the precipitation reaction from the view of thermodynamics. At the same time,the refined quartz sand can also improve the precipitation reaction from the view of kinetics,which is selected as the best carrier. The removal efficiency of Hg^（2＋） from the untreated wastewater and the treated wastewater can achieve 98. 54%,99. 20%,respectively,by using refined quartz sand as carrier. The Hg^（2＋） removal effect for untreated wastewater is lower than that of the treated wastewater and exhibits increased turbidity.