酸性侵蚀对固化市政污泥Ca浸出的影响  

Influence of Acid Attack on Ca Leaching of Solidified Municipal Sludge

作　　者：汪明亮 徐浩青 范惜辉 WANG Mingliang;XU Haoqing;FAN Xihui(Nanjing Environment Group Co.Ltd.,Nanjing 210026,China;Jiangsu University of Science and Technology,Zhenjiang 212003,Jiangsu China)

机构地区：[1]南京环境集团有限公司,南京210026 [2]江苏科技大学,江苏镇江212003

出　　处：《河南科学》2021年第6期899-904,共6页Henan Science

基　　金：江苏省自然科学青年基金(BK20190963);江苏省产学研合作项目(BY2019053);江苏省高校自然科学基金(19KJB560003)。

摘　　要：固化市政污泥作为填埋场临时覆土等土材料使用具有广阔的前景,但是填埋场渗沥液等溶液具有很强的酸性.为探讨固化污泥在酸性环境中的稳定性,以普通硅酸盐水泥(OPC)和硫铝酸盐水泥(SAC)为固化材料进行了酸性环境下的半动态浸出试验和热重分析实验.结果表明:在pH=2的较强酸性环境中,固化污泥更容易受到侵蚀,容易形成剥离.但是Ca浸出的扩散系数低于3×10^(-13) m^(2)/s,可以认为水化产物中Ca的迁移能力较低,水化产物具有较好的稳定性.SAC固化污泥中Ca的浸出受扩散控制,主要是由于水化产物钙矾石的降解.Solidified municipal sludge has broad prospects for use as a landfill temporary cover or other soil materials,but the landfill leachate and other solutions may have strong acidity.In order to explore the stability of solidified sludge in acidic environment,a semi-dynamic leaching test and thermogravimetric analysis experiment were carried out with ordinary Portland cement(OPC)and sulphoaluminate cement(SAC)as solidifying materials.The results showed that in a strong acidic environment with pH=2,the solidified sludge was more easily eroded and easy to form peeling.However,the diffusion coefficient of Ca leaching was lower than 3×10^(-13) m^(2)/s.It could be considered that the migration ability of Ca in the hydrated product was low,and the hydrated product had better stability.The leaching of Ca from SAC solidified sludge was controlled by diffusion,which was mainly due to the degradation of ettringite,a hydration product from SAC.

关 键 词：固化污泥 半动态浸出 酸性侵蚀 Ca浸出 

分 类 号：X703[环境科学与工程—环境工程]