活性炭对燃煤电厂烟气中有机污染物的吸附特性研究  

Adsorption characteristics of organic pollutants in flue gas of coal-fired power plant by activated carbon

作　　者：马修卫 赵孟亮 侯勇[1] 李守原 吕浩[1] 杨林军[1] MA Xiuwei;ZHAO Mengliang;HOU Yong;LI Shouyuan;LV Hao;YANG Linjun(Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education of Southeast University,Nanjing 210096,China;Shangdong Jinke Engineering Co.,Ltd.,Shangdong 255000,China)

机构地区：[1]东南大学能源热转换及其过程测控教育部重点实验室,江苏南京210096 [2]山东金柯工程设计有限公司,山东淄博255000

出　　处：《电力科技与环保》2022年第1期18-26,共9页Electric Power Technology and Environmental Protection

基　　金：国家重点研发计划项目(2018YFB0605200);江苏省研究生科研与实践创新计划项目(KYCX20_0092);中央高校基本科研业务费专项资金资助(3203002101D)。

摘　　要：活性炭吸附是燃煤电厂烟气中有机污染物减排的有效方法。在固定床实验装置和吸附剂喷射耦合布袋除尘实验装置上开展了甲苯和氯苯的吸附脱除实验,并在实际燃煤电厂中开展了活性炭喷射脱除有机污染物试验。结果表明中高温、低浓度环境下,甲苯的饱和吸附容量为9.9~49.9 mg/g;甲苯吸附主要以微孔吸附为主,温度升高吸附容量降低。准一级动力学模型可以较好的拟合低浓度甲苯在中高温环境下的吸附过程;较低的甲苯浓度使活性炭外表面扩散成为影响吸附速率的关键步骤。中高温环境下甲苯以物理吸附为主,也存在一定量的化学吸附。吸附喷射耦合布袋除尘对甲苯和氯苯的脱除效率分别为33.2%和44.1%,其吸附容量低于固定床上的饱和吸附容量,这主要因为活性炭与有机物分子的接触时间有限。提高吸附剂喷射量可以明显提高有机污染物的去除效率。在实际燃煤烟气中有机污染物组成复杂,活性炭喷射对不同有机污染物的去除效率不同,沸点较高的1-十二烯具有较高的去除效率,多环芳烃的总体去除效率高于24种常规的挥发性有机污染物。Activated carbon(AC)adsorption is an effective method to reduce organic pollutant emission from coal-fired flue gas.In this work,the adsorption experiments of toluene and chlorobenzene are carried out on a fixed-bed and an adsorbent injection coupled with bag filter system;the adsorption experiments of organic pollutant are performed in coal-fired power plant by AC injection.The results show that the saturation adsorption capacity of toluene is 9.9~49.9 mg/g at medium-high temperature and low-concentration condition.Toluene is mainly adsorbed in microporous,and its adsorption capacities are decreased with increasing the temperature.The pseudo first order kinetic model fits the adsorption process of toluene at medium-high temperature well.The lower concentration makes the diffusion of organic pollutant on the outer surface of AC a key step affecting the adsorption rate.At medium-high temperature condition,the removal of toluene is mainly physical adsorption,but there is also a certain amount of chemical adsorption.The adsorption efficiency of toluene and chlorobenzene by AC injection coupled with bag filter are 33.2%and 44.1%,respectively;and their adsorption capacities are lower than the saturation adsorption capacities on fixed-bed,which is mainly due to the limited contact time between AC and organic molecules.Increasing the amount of adsorbent injection significantly improves the removal efficiency.The composition of organic pollutants in coal combustion flue gas is complex,the removal efficiency differs for different organic pollutants with AC injection.1-dodecene,which has higher boiling point,has higher removal efficiency.The removal efficiency of PAHs is higher than that of conventional VOCs.

关 键 词：吸附 燃煤烟气 有机污染物 活性炭 吸附动力学 

分 类 号：TK229[动力工程及工程热物理—动力机械及工程] X511[环境科学与工程—环境工程]