市政污泥生物炭稳定红壤中重金属的地球化学机制及关键影响因素

项目名称： 市政污泥生物炭稳定红壤中重金属的地球化学机制及关键影响因素

项目编号： No.41272383

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 章卫华

作者单位： 中山大学

项目金额： 85万元

中文摘要： 申请者已有研究发现，由市政污经氧化沟处理，产生的污泥通过铁盐调理浓缩脱水后，在400oC2小时缺氧干馏而成的污泥生物炭对Pb（II）和As(III)均具有可观的吸附量，且吸附后金属都较稳定。且干馏过程固定污泥原有碳和重金属元素，减少温室气体的排放及重金属释放。故污泥生物炭可成为阴阳离子重金属污染土壤的良好稳定剂。不同于单一组分多孔物质，污泥生物炭表面富含无机矿物和有机碳基组分，当其应用于土壤时，与土壤组分，溶液离子和有机质等相互作用，故涉及地球化学机制芜杂，其关键因素和潜在风险尚不明确，严重制约其实际应用。故本研究拟先利用水相试验和官能团遮掩、FTIR、TEM-XPS、EXAFS微观手段来确定其在水相中稳定阴阳重金属的地球化学机制。在此基础上，筛选适合的影响因子和环境条件，设计正交实验，模拟其在红壤中相关地球化学过程，从而确定污泥生物炭对稳定红壤中重金属的地球化学过程及关键因素。

中文关键词： 市政污泥；红壤；重金属；稳定；砷

英文摘要： The current study conducted by the applicant shows that when the sludge produced in the oxidation ditch of manucipal wastewater treatment plants is conditioned with ferric salts, then concentrated, dewatered, and pyrolyzed into biochar at 400 oC for 2 hours, and the resulting biochar can immobilize considerable mass of Pb(II) and As(III) in the aqueous soltuion. The pyrolysis process was also found to stabilize the original black carbons and heavy metals in the sludge, reducing the emission of green house gas and heavy metals. Therefore, this sludge-derived sludge seems very promising to be an effective amendment agent for soils contaminated with both cationic and anionic heavy metals. Different from the tranditional homogeneous porous media, sludge-derived biochar is rich in inorganic minerals and organic components. When it is appplied in the soil, the soil itself components, ions in the soil solution, soil organic matter may interact with the biochars, and the invovled geochemcial mechanisms are rather complicated. The corresponding key factors and potenital environmental risk are not clear so far, which would greatly limit its wide application in practics. Therefore, the geochemcial mechanisms between these metals in aqeuous phase and biochar is proposed to be investigated in this proposal with the aid of se

英文关键词： municipal wastewater sludge；red soil；heavy metals；stablization；As(III)