废弃电路板冶炼烟灰脱溴工艺研究

针对废弃电路板冶炼烟灰的特性,提出了碱性焙烧—水浸—熔炼综合回收工艺,通过添加碱性剂将烟灰中的金属溴氯化物转化为氧化物,实现了有价金属与溴的高效分离。探索了焙烧温度、加碱量、碱性剂类型对浸出渣组成及脱溴率的影响。在焙烧温度650~800℃,碱性剂氢氧化钠加入量为烟灰质量25%的优化工艺条件下,溴脱除率达到90%以上。滤渣主要组成为PbO、ZnO、CuO等金属氧化物和碳,结晶盐中的主要杂质为F、Al、S和K,NaCl和NaBr的含量达到90%以上。

Study on Debromination of Waste Circuit Board Smelting Ash

Comprehensive recovery process,i.e.,alkaline roasting—water leaching—smelting,was proposed based on characteristics of smelting ash of waste circuit boards.Metal bromochloride in ash was converted into oxide by adding alkaline agent,as a result,efficient separation of valuable metals and bromine was realized.Effects of roasting temperature,alkali adding amount and alkaline agent type on composition of leaching residue and debromination rate were investigated.Removal rate of bromine is 90%above under the optimum conditions including roasting temperature of 650—800℃,NaOH as alkaline agent,and dosage of NaOH of 25%of ash mass.Leaching residues mainly consist of PbO,ZnO,CuO and carbon.Main impurities in crystalline salt are F,Al,S and K,and content of NaCl and NaBr is both 90%above.