Raw coal is used by many suburban and rural households for cooking and heating and results in severe air pollution,especially problematic SO_(2) emissions.A source treatment strategy was proposed to reduce SO_(2) emis...Raw coal is used by many suburban and rural households for cooking and heating and results in severe air pollution,especially problematic SO_(2) emissions.A source treatment strategy was proposed to reduce SO_(2) emissions,which used the co-pyrolysis of raw coal with a CaCO3 additive to produce clean coke.The effect of Ca/S molar ratio on the SO_(2) capture efficiency of clean coke was investigated,and the SO_(2) retention efficiency was optimized at a Ca/S molar ratio of 1.5.The sulfur retention mechanism of clean coke was attributed to:(1)CaCO3 decomposition to CaO and partial reaction of CaO with H2S to generate CaS during pyrolysis.(2)Transformation of the remaining sulfur in the clean coke to SO_(2) during combustion,capture by unreacted CaO to form CaSO_(4),and direct oxidation of CaS to CaSO_(4).The feasibility of SO_(2) emission reduction by clean coke in a practical household stove was verified.展开更多
基金supported by the National Natural Science Foundation of China(No.21878210)Shanxi Province patent promotion grant program(20200719)+1 种基金Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2019L0313)sponsored by Mettler Toledo and Taiyuan Green Coke Energy Co.,Ltd.(China).
文摘Raw coal is used by many suburban and rural households for cooking and heating and results in severe air pollution,especially problematic SO_(2) emissions.A source treatment strategy was proposed to reduce SO_(2) emissions,which used the co-pyrolysis of raw coal with a CaCO3 additive to produce clean coke.The effect of Ca/S molar ratio on the SO_(2) capture efficiency of clean coke was investigated,and the SO_(2) retention efficiency was optimized at a Ca/S molar ratio of 1.5.The sulfur retention mechanism of clean coke was attributed to:(1)CaCO3 decomposition to CaO and partial reaction of CaO with H2S to generate CaS during pyrolysis.(2)Transformation of the remaining sulfur in the clean coke to SO_(2) during combustion,capture by unreacted CaO to form CaSO_(4),and direct oxidation of CaS to CaSO_(4).The feasibility of SO_(2) emission reduction by clean coke in a practical household stove was verified.