探索大修渣除氟除氰工艺

Exploring the Process of Removing Fluorine and Cyanide From Overhaul Slag

电解铝大修渣中,氰化物及氟化物含量超标,属于危险废物。通过实验研究了漂白粉作为除氰剂,氢氧化钙作为除氟剂时,大修渣的球磨粒径、液固比、除氰剂及除氟剂用量、反应时间、温度对除氰除氟效果的影响。试验结果表明:大修渣的球磨粒径越小,溶出氰化物及氟化物含量越多;液固比对大修渣溶出的氰化物及氟化物影响不大;漂白粉与大修渣的最佳用量为大修渣/除氰剂=6~8,最佳反应时间为30~40 min;除氟剂与大修渣的最佳用量为大修渣/除氟剂=8~10,最佳反应时间30~40 min;温度在10~50℃之间变化时,对除氰及除氟效果影响不大。

In the electrolytic aluminum overhaul slag, the content of cyanide and fluoride exceeds the standard and belongs to hazardous waste. Through the experiment, the bleaching powder is used as a cyanide removal agent When calcium hydroxide is used as a defluoridation agent, the ball milling particle size, liquidsolid ratio, cyanide removal agent and defluorination agent dosage, reaction time and temperature are used to remove cyanide and fluoride, influences. The test results show that the smaller the particle size of the ball mill of the overhaul slag, the more the cyanide and fluoride content are dissolved;the liquid-solid ratio has little effect on the cyanide and fluoride dissolved by the overhaul slag;The optimum dosage of bleaching powder and overhaul slag is overhaul slag/cyanide removal agent=6-8, the optimum reaction time is 30-40 min;the optimum dosage of fluorination agent and overhaul slag is overhaul slag/defluorination agent=8-10 The optimum reaction time is 30-40 min;when the temperature is changed between 10-50℃, the effect of removing cyanide and fluorine removal is not significant.