Co-pyrolysis of sludge and kaolin/zeolite in a rotary kiln:Analysis of stabilizing heavy metals

作     者：Qian Li Zhaoping Zhong Haoran Du Xiang Zheng Bo Zhang Baosheng Jin Qian Li;Zhaoping Zhong;Haoran Du;Xiang Zheng;Bo Zhang;Baosheng Jin

作者机构：Southeast UniversityKey Laboratory of Energy Thermal Conversion and Control(Ministry of Education)Nanjing210096China 

出 版 物：《Frontiers of Environmental Science & Engineering》 (环境科学与工程前沿（英文）)

年 卷 期：2022年第16卷第7期

页      面：21-33页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 

基　　金：funded by National Key Research and Development Program of China(No.2018YFC1901202) 

主　　题：Co-pyrolysis Sewage sludge Heavy metals Rotary kiln Immobilization mechanism 

摘      要：Pyrolysis is a promising technique used for treating of sewage ***,the application of pyrolysis products is limited due to the presence of heavy *** this study,sewage sludge mixed with kaolin/zeolite was pyrolyzed in a rotary kiln,aiming to improve the immobilization of heavy metals in pyrolytic *** total concentrations,speciation distributions,leaching toxicities,and potential ecological risk indices of heavy metals in pyrolysis biochar were explored to examine the effects of kaolin/zeolite and pyrolytic temperature on immobilizing heavy ***,mineral composition and surface morphology of biochar were characterized by X-ray diffraction and scanning electron microscopy to reveal the potential mechanism of immobilizing heavy *** pyrolysis temperature facilitated the stabilization of heavy metals in pyrolysis *** proportions of stable heavy metals in biochar obtained at 650℃ were 54.50%(Cu),29.73%(Zn),79.29%(Cd),68.17%(Pb)and 86.70%(Cr).Compared to sewage sludge,the potential contamination risk index of pyrolysis biochar obtained at 650℃ was reduced to 17.01,indicating a low ecological *** addition of 7%kaolin/zeolite further reduced the risk index of co-pyrolysis biochar prepared at 650℃ to 10.86/*** characterization of biochar revealed that increase in the pyrolysis temperature and incorporation of additives are conducive to the formation of stable heavy *** study demonstrates that the formation of stable mineral compounds containing heavy metals is the key to stabilizing heavy metals in pyrolysis biochar.