Hydrothermal solidification behavior of municipal solid waste incineration bottom ash without any additives.
Hydrothermal solidification behavior of municipal solid waste incineration bottom ash without any additives.
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DOI：
10.1016/j.wasman.2013.01.038
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发表时间：
2013-05
期刊：
影响因子：
8.1
通讯作者：
Z. Jing;Xinwei Fan;Lei Zhou;Jun-jie Fan;Y. Zhang;Xiaohui Pan;E. H. Ishida
中科院分区：
文献类型：
--
作者：
Z. Jing;Xinwei Fan;Lei Zhou;Jun-jie Fan;Y. Zhang;Xiaohui Pan;E. H. Ishida
在200°C、1.56MPa的蒸汽压力下，采用水热法对城市生活垃圾焚烧底灰进行固化处理，研究了添加和不添加消石灰（氢氧化钙）对固化效果的影响。试验结果表明，CSH凝胶或雪硅钙石对强度发展起主要作用，不加任何外加剂时CSH凝胶易于形成，而添加消石灰有利于雪硅钙石的形成。托贝莫来石对强度发展的影响大于CSH凝胶。浸出结果表明，水热处理后，固化体中重金属溶出量得到有效降低。结果表明，Pb2+和Zn2+在雪硅钙石和CSH凝胶中的固定作用优于Cr6+，这可能是雪硅钙石和CSH凝胶中结构Ca2+更易被Pb2+和Zn2+交换的原因。此外，强度增强与淋溶浓度之间存在密切关系，强度越高，重金属的固定效果越好。
Municipal solid waste incineration (MSWI) bottom ash could be solidified with and without slaked lime (calcium hydroxide) addition by a hydrothermal method under steam pressure of 1.56MPa at 200°C for up to 72h. Experimental results showed that CSH gel or tobermorite exerted a main influence on strength development, and without any additives CSH gel was easy to form, while slaked lime addition favored to form tobermorite. Tobermorite seemed to exert a larger effect on the strength development than CSH gel. Leaching results showed that the concentrations of heavy metals dissolved from the solidified specimens were effectively reduced after hydrothermal processing. The immobilization was mainly due to the tobermorite or CSH gel formation, and Pb2+and Zn2+seemed to be fixed more readily than Cr6+, which might be the reason that the structural Ca2+within tobermorite or CSH gel was exchanged by Pb2+and Zn2+more easily than Cr6+. In addition, there existed a close relationship between leaching concentration and strength enhancement, and a higher strength seemed to exert a larger effect on immobilization of heavy metals.