Physicochemical and environmental properties of arsenic sulfide sludge from copper and lead-zinc smelter  

铜/铅锌冶炼厂硫化砷渣的理化与环境特性

作　　者：Li-wei YAO Xiao-bo MIN Hui XU Yong KE Yun-yan WANG Zhang LIN Yan-jie LIANG De-gang LIU Qiu-jing XU Yu-yang HE 姚理为;闵小波;徐慧;柯勇;王云燕;林璋;梁彦杰;刘德刚;许秋婧;何逾洋(中南大学冶金与环境学院,长沙410083;中南大学国家重金属污染防治工程技术研究中心,长沙410083)

机构地区：[1]School of Metallurgy and Environment,Central South University,Changsha 410083,China [2]Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution,Central South University,Changsha 410083,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第7期1943-1955,共13页中国有色金属学报（英文版）

基　　金：Projects(51904354,51634010)supported by the National Natural Science Foundation of China;Project(51825403)supported by the National Science Fund for Distinguished Young Scholars,China;Projects(2018YFC1903301,2018YFC1900301)supported by the National Key R&D Program of China。

摘　　要：Physicochemical properties of arsenic sulfide sludge(ASS) from copper smelter(ASS-I) and lead-zinc smelter(ASS-II) were examined by XRD, Raman spectroscopy, SEM-EDS, TG-DTA, XPS and chemical phase analysis method. The toxicity characteristic leaching procedure(TCLP), Chinese standard leaching tests(CSLT), three-stage sequential extraction procedure(BCR) and batch leaching experiments(BLE) were used to investigate the environmental stability. The ASSs from different smelters had obviously different physicochemical and environmental properties. The phase composition and micrograph analysis indicate that ASS-I mainly consists of super refined flocculent particles including amorphous arsenic sulfide adhered with amorphous sulfur and that ASS-II mainly consists of amorphous arsenic sulfide. The valence state of arsenic in both sludges is trivalent, but the valence composition of sulfur is quite different. The ASSs have thermal instability properties. The results of TCLP and CSLT indicate that the concentrations of As and Pd in the leaching solution exceed the standard limits. More than 5% and 90% of arsenic are in the form of acid soluble and oxidizable fractions, respectively, which explains the high arsenic leaching toxicity and environmental activity of ASS. This research provides comprehensive information for the disposal of ASS from copper and lead-zinc smelter.以铜冶炼和铅锌冶炼产生的硫化砷渣为研究对象,采用XRD、Raman、SEM-EDD、TG-DTA、XPS和化学物相分析等检测手段研究其理化特性。采用毒性浸出程序(TCLP)、毒性浸出测试国家标准(CSLT)、三步连续浸提程序(BCR)和批次浸出实验(BLE)分析硫化砷渣的环境稳定性。不同冶炼厂的硫化砷渣理化和环境特性具有明显的差异。物相组成和显微分析表明,ASS-I主要由超细的絮状颗粒组成,这种颗粒为粘附有无定型硫的无定型硫化砷。AAS-II主要组成为无定型硫化砷。两种来源的硫化砷渣中砷均为正三价,但是硫的价态组成则有所不同。同时,两种来源的硫化砷渣均具有热不稳定性。TCLP和CSLT结果表明,浸出液中砷和铅的浸出浓度超过了标准限值。超过5%和90%的砷以酸可溶态和可氧化态赋存,这解释了硫化砷渣砷浸出毒性高、环境活性强的原因。本研究为铜和铅锌冶炼企业的硫化砷渣的处置提供了全面的信息参考。

关 键 词：arsenic sulfide sludge heavy metals physicochemical properties environmental availability leaching toxicity 

分 类 号：X758[环境科学与工程—环境工程]