基于响应面法探究汞铊矿围岩中典型重金属形态转化的最优影响因素  

Optimal influences on the transformation of typical heavy metal speciation in the surrounding rocks of mercury-thallium mines explored based on response surface methodology

作　　者：强一彬 彭小裕 吴永贵[1,2,3] 薛蓉杰 李夏琳 杨稿 王宁宁 QIANG Yibin;PENG Xiaoyu;WU Yonggui;XUE Rongjie;LI Xialin;YANG Gao;WANG Ningning(School of Resource and Environmental Engineering,Guizhou University,Guiyang 550025;Field Science Observation and Research Station of Ministry of Education of Guizhou Karst Environment Ecosystem,Guiyang 550025;Engineering Research Center for Ecological Restoration Technology for Inferior Environments of Guizhou Province,Guiyang 550025)

机构地区：[1]贵州大学资源与环境工程学院,贵州550025 [2]贵州喀斯特环境生态系统教育部野外科学观测研究站,贵州550025 [3]贵州省劣境生态修复技术工程研究中心,贵州550025

出　　处：《环境科学学报》2024年第11期253-264,共12页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.52160015);贵州省百层次人才项目(No.黔科合平台人才[2020]6002-2);贵州省发改委省级高新技术产业化示范工程项目(No.黔发改高技[2020]896号)。

摘　　要：环境因素的改变对矿山固体废弃物中重金属的赋存形态存在显著影响,通过调控环境因素来抑制矿山固体废弃物中重金属的活化,阻控其释放迁移,同时降低其生物有效性,可为矿区周边重金属的污染防治提供理论支撑.本文选取pH、Fe^(3+)浓度、胡敏酸(HA)浓度和反应时间(t)4个影响因素进行中心组合试验设计,模拟静态浸出试验,通过响应面法分析了不同影响因素下汞铊矿围岩中汞和铬赋存形态的转化规律,探究了各影响因素间的交互作用及影响程度,以汞铊矿围岩中富含的Hg、Cr各赋存形态含量为响应值,使用Design-Expert 8.0.6软件对数据进行拟合分析,建立各影响因素和响应值之间的数学模型.结果表明:4个因素对Hg和Cr 4种赋存形态中的弱酸提取态产生显著影响,且影响程度无显著差异,主次顺序为:Fe^(3+)>pH>HA>t.4个因素间Fe^(3+)与HA存在显著的交互作用,较高浓度的Fe^(3+)和HA均能促进Hg、Cr的氧化态和残渣态向弱酸提取态和还原态转化,增加了Hg和Cr向环境释放迁移的风险.在初始浸提液pH为4.07,Fe^(3+)浓度为19.92 mmol·L^(-1),HA含量为3.98 g·L^(-1),浸泡1.51 d时,Hg弱酸提取态达最高值,为28.94 mg·kg^(-1);当初始浸提液pH为2.0,Fe^(3+)浓度为20 mmol·L^(-1),HA含量为4.00 g·L^(-1),浸提7.00 d时,Cr弱酸提取态含量可达4.85 mg·kg^(-1).本文将响应面分析法引入到矿山固体废弃物重金属赋存形态转化的研究中,丰富了该领域的研究方法,相关研究结果可为深入开展汞铊矿固体废弃物中重金属的地球化学过程、高效脱除及环境风险管控研究提供参考.Environmental factor changes significantly influence the speciation of heavy metals in mine solid waste.Regulating environmental factors to inhibit the activation of heavy metals,control their release and migration,and reduce their bioavailability can theoretically support the prevention and control of heavy metal pollution surrounding the mining area.This study selected pH,Fe^(3+)concentration,humic acid(HA)concentration,and reaction time(t)as the influencing factors for central combination experimental design,conducted simulated static leaching experiments,and analyzed the transformation laws of the Hg and Cr speciation in surrounding rocks of mercury-thallium mines under varied factors using response surface methodology.It explored the interaction and influence of each factor,considering the content of different speciation forms of Hg and Cr in the surrounding rocks of mercury-thallium mine as the response values.Data were analyzed using Design-Expert 8.0.6 software to establish mathematical models linking influencing factors and response values.The results showed that a significant impact of the four factors on the weak acid-extractable fractions of Hg and Cr,with Fe^(3+)having the greatest influence,followed by pH,HA,and t,with no significant difference in the degree of influence.A significant interaction was observed between Fe^(3+)and HA among the four factors.Higher concentrations of Fe^(3+)and HA both promoted the transformation of oxidative and residual fractions of Hg and Cr to weak acid-extractable and reducible fractions,increasing the risk of Hg and Cr release and migration into the environment.At an initial leaching solution pH of 4.07,Fe^(3+)concentration of 19.92 mmol·L^(-1),HA content of 3.98 g·L^(-1),soaked for 1.51 d,the weak acid-extractable fraction of Hg reached its highest value at 28.94 mg·kg^(-1).At a pH of 2.0,Fe^(3+)concentration of 20 mmol·L^(-1),HA content of 4.00 g·L^(-1),and leached for 7.00 d,the weak acid-extractable fraction of Cr reached 4.85 mg·kg^(-1).This study introdu

关 键 词：矿山固体废弃物 重金属 响应面法 环境因素 赋存形态 

分 类 号：X705[环境科学与工程—环境工程]