铟萃余液氧化除铁渣对回转窑尾气水脱氟作用研究

Effect of Oxidation Iron Removal Slag from Indium Raffinate on Defluoridation of Scrubbing Water from Rotary Kiln

采用广西某公司提铟流程中产生的萃余液氧化除铁渣作为除氟剂,对回转窑尾气洗水进行除氟处理,在溶液初始pH≈5.0,除氟剂添加量为理论量的5倍,温度40℃,机械搅拌条件下,尾气水中的氟离子浓度降至50 mg/L以下,氟离子脱除率达90%以上。该脱氟技术应用于工业试验,溶液中氟离子浓度由370 mg/L下降至50 mg/L以下。

The iron removal slag from indium raffinate generated from indium flowsheet in one Guangxi company was taken as a fluoride removal agent in defluorination of scrubbing water from rotary kiln. With an initial pH of solution around 5.0, the addition of fluoride removal agent 5 times as much as the theoretical amount and temperature at 40 ℃, the fluorine ion concentration in the solution was decreased to less than 50 mg/ L after mechanical agitation, resulting in the fluorine ion removal rate exceeding 90%. This defluorination technique was applied into commercial experiment, leading to a satisfactory result, with fluorine ion concentration in the solution reduced to less than 50 mg/ L from 370 mg/ L.