褐煤基粉状活性焦制备小试试验初步研究

Primary study on the pilot-scale experiment of preparation for powdered activated coke from lignite

活性焦烟气脱硫是资源化脱硫的主要技术之一,针对目前成型颗粒活性焦移动床脱硫工艺存在的活性焦成本高的约束性问题,提出并开发了煤粉快速炭化活化一步法制备脱硫用粉状活性焦(以下简称粉焦)的工艺方法。基于实验室基础研究数据搭建了30 kg/h级粉焦产量的小试试验装置及系统,进行了褐煤快速制备粉焦的初步试验,并将小试结果与沉降炉机理试验结果比较分析。在小试条件下,蒙东褐煤制备粉焦的产率为38%,低于机理试验得率;粉焦孔隙以微孔为主,且微孔孔容及比表面积优于2组机理试验制得的粉焦;粉焦2 h的SO2吸附量(质量分数)为6.1%,低于2组机理试验结果,应为小试与机理粉焦粒径和孔隙结构差异导致;小试制焦副产热解气中可燃气CO+H2+CH4的体积分数为7.3%,高于2组机理试验热解气中可燃气的体积分数。小试结果初步验证了低阶煤快速制备脱硫用粉焦工艺的可行性。

Flue gas desulfurization(FGD)using activated coke is one of the main technologies for sulfur recovery.In view of the high cost of activated coke in the desulfurization process of the current shaped particle activated coke moving bed,a one-step powdered activated coke(PAC)preparation process for FGD was proposed and developed,which can carbonize and activate pulverized coal ly.Based on the basic research data from the laboratory,a pilot-scale experimental device and system with a PAC output of 30 kg/h was built,and a preliminary test for the rapid preparation of PAC was made.Comparative analysis of the results from the pilot-scale experiment and experimental study was conducted.Under the pilotscale experimental conditions,the PAC yield prepared from Mengdong lignite was 38%,lower than that under experimental condition.The pores of the PAC from the pilot-scale experiment were mainly micropores,whose pore volume and specific surface area were better than the PAC from two lab experiments.The adsorption capacity of PAC from the pilot-scale experiment was 6.1%per two hours.It was lower than that in two lab experiments,which should be caused by the difference in particle size and pore structure.The volume fraction of combustible components(CO+H2+CH4)in pyrolysis gas,a byproduct in PAC preparation process in the pilot-scale experiment,was 7.3%,higher than that in lab experiments.The results of the pilot-scale experiments preliminarily verified the feasibility of the process of PAC rapid preparation from lignite.