Using sorbents to control heavy metals and particulate matter emission during solid fuel combustion  

作　　者：Hong Yao Ichiro Naruse 

机构地区：[1]State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China [2]Department of Mechanical Science & Engineering, Nagoya University, Nagoya 464-8603,Japan

出　　处：《Particuology》2009年第6期477-482,共6页颗粒学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grants 50721140649,50776038 and 50721005);The Programme of Introducing Talents of Discipline to Universities("111" Project,No.B06019);Program for New Century Excellent Talents in University (No.NCET-08-0227)

摘　　要：Some of the heavy metals in coal and wastes vaporize during combustion, concentrate in fine particulates, and emit with the flue gas into the atmosphere, to produce adverse effect on environment and health. This study first investigates the fate of the heavy metal species, especially Pb, Cd and Cr, known as semi-volatile, in various flue gases, especially in the presence of HCI and SO2, by chemical equilibrium calculation, in which, Si and Ca were proposed as base sorbent materials to capture Pb, Cd and Cr. Then Si- and Ca-based compounds as well as waste materials used as sorbents were optimized to capture the heavy metals. Finally, the optimal sorbent was tested in actual burning of dried sewage sludge as solid fuel, to evaluate the effectiveness of the sorbent. Calculated results show that Cl increases the volatility of most heavy metals, while SO2 enhances formation of condensed phases. Among the sorbents tested, kaolin appears most efficient to capture Pb and Cd. For sludge combustion with kaolin addition, both Pb and Cd were shifted from sub-micron to macro-sized particles, and accompanied by considerable decrease of 0.1 μm particles.Some of the heavy metals in coal and wastes vaporize during combustion, concentrate in fine particulates, and emit with the flue gas into the atmosphere, to produce adverse effect on environment and health. This study first investigates the fate of the heavy metal species, especially Pb, Cd and Cr, known as semi-volatile, in various flue gases, especially in the presence of HCI and SO2, by chemical equilibrium calculation, in which, Si and Ca were proposed as base sorbent materials to capture Pb, Cd and Cr. Then Si- and Ca-based compounds as well as waste materials used as sorbents were optimized to capture the heavy metals. Finally, the optimal sorbent was tested in actual burning of dried sewage sludge as solid fuel, to evaluate the effectiveness of the sorbent. Calculated results show that Cl increases the volatility of most heavy metals, while SO2 enhances formation of condensed phases. Among the sorbents tested, kaolin appears most efficient to capture Pb and Cd. For sludge combustion with kaolin addition, both Pb and Cd were shifted from sub-micron to macro-sized particles, and accompanied by considerable decrease of 0.1 μm particles.

关 键 词：Combustion Heavy metal Paniculate matter Sorbent 

分 类 号：TQ517.3[化学工程] TK421.2[动力工程及工程热物理—动力机械及工程]