摘要
针对锌废渣中重金属污染环境,尤其是废渣中铅含量高于1%,无法作为无害渣使用的问题,本文采用自动矿物分析仪(MLA)分析氯盐浸渣(对锌废渣经过焙烧-酸浸得到的酸浸渣进行氯盐浸出得到)中铅的物相主要为PbBa(SO_4)_2,盐酸或含HCl的饱和NaCl溶液可将其有效分解,可使尾渣中铅含量达到<1%效果。在此基础上,研究不同浸出体系对酸浸渣进行一步浸出,以期选出较优的浸出体系及浸出条件,达到使废渣中的铅含量降到1%以下的目的。研究结果表明:"饱和NaCl溶液+补加HCl+补加NaCl"体系浸出酸浸渣的效果明显好于"含HCl的饱和NaCl溶液+补加NaCl"和"饱和NaCl溶液+补加NaCl"两种体系浸出酸浸渣的效果,但出于HCl成本高考虑,选取"饱和NaCl溶液+补加NaCl"作为浸出剂及浸出方式。"饱和NaCl+补加NaCl"浸出酸浸渣的反应条件为:酸浸渣50g,250m L饱和NaCl,温度≥60℃,反应2h后补加15g NaCl,继续反应3h,Pb的浸出率>91%,Pb在尾渣中的含量达到0.85%≤Pb<1%。
Aiming at the problem that heavy-metal polluting environment,especially lead content higher than 1% could not make zinc smelting slag become harmless slag,chloride-leaching slag（zinc slag was roastd and acid leached to get acid-leaching residue,and acid-leach residue was chloride-leached to get chloride-leaching slag）was analyzed by MLA,and PbBa（SO4）2 was the main phase of Pb in the chloride-leaching slag.And PbBa（SO4）2 could be decomposed by HCl or saturated NaCl containing HCl system,which could make the lead content in the slag lower to 1%.On the above basis,one step leaching effects of different leaching systems on lead in the acid-leaching residue were studied to get the optimum leaching system and conditions and to make the lead content in the slag lower to 1%.The results were as follows：the leach effect of ＂saturated NaCl ＋ supplementing HCl and NaCl＂ system was obviously better than that of ＂saturated NaCl containing HCl ＋ supplementing NaCl＂ system and＂saturated NaCl ＋ supplementing NaCl＂system.Because of high cost of HCl,the ＂saturated NaCl ＋ supplementing NaCl＂ system was selected as the leaching reagent and leaching method whose leaching effect met the requirements of lead content lower than 1% in the tailings.The suitable leaching conditions of ＂saturated NaCl ＋ supplementing NaCl＂ was as follows：50 g acid-leach residue,250 m L saturated NaCl,above 60℃,added 15 g NaCl after 2 h leaching time,continuing to react 3 h,the results was that the leaching rate of lead was above 91% and lead content in the tailings was 0.85%≤Pb1%.
出处
《化工进展》
EI
CAS
CSCD
北大核心
2017年第12期4672-4678,共7页
Chemical Industry and Engineering Progress
基金
广东省科技计划(2015A020215018,2017B090907026)
广东省自然基金(2016A030313801)
广东省科学院院属骨干科研机构创新能力建设专项项目(2017GDASCX-0110)
国家自然科学基金(51704081)项目
关键词
湿法锌冶炼废渣
铅
氯化钠
盐酸
废物处理
浸取
分离
wet smelting slag of zinc
lead
sodium chloride
hydrochloric acid
waste treatment
leaching
seperation
