O_2/CO_2气氛燃煤半焦孔隙特性分析  

ANALYSIS OF PORE STRUCTURE IN COAL CHAR OBTAINED IN AN O_2/CO_2 ENVIRONMENT

作　　者：李庆钊[1] 赵长遂[1] 陈晓平[1] 武卫芳[1] 李英杰[1] 

机构地区：[1]东南大学能源与环境学院,江苏南京210096

出　　处：《工程热物理学报》2009年第9期1605-1608,共4页Journal of Engineering Thermophysics

基　　金：国家重点基础研究发展规划资助项目(No.2006CB705806);江苏省普通高校研究生科研创新计划资助项目(No.CX07B-091Z);东南大学优秀博士学位论文基金资助项目

摘　　要：在沉降炉上制备了不同燃烧气氛、不同燃尽程度的半焦,采用低温氮吸附仪和扫描电子显微镜测定了其孔隙结构和表面形态。结果表明,所取的半焦试样均具有完整且连续的孔结构体系;但在相同的操作条件下,O_2/CO_2气氛下半焦试样的孔结构参数及其分形维数均小于相同O_2浓度的O_2/N_2气氛下的情况;两种气氛下煤焦的燃尽过程中,孔隙结构参数(S_(BET)、V_(BJH)和d_(pore))随燃尽率的增加均呈减小趋势;SEM图像的定性分析结果与N_2吸附的定量测量吻合较好。研究结果为深入认识O_2/CO_2气氛下煤粉的孔隙结构与其燃烧特性的关系提供了基础。In a drop-tube furnace, coal char samples with various burn-off rates, were prepared in different environments and analyzed with N2 adsorption analyzer and scanning electronic microscope （SEM）. Results show that all these samples are possessed in a continuous and integral pores system, but the CO2 char （derived in O2/CO2 environment） shows lower specific surface area and specific pore volume than that of N2 char. During the combustion processes, pore structure parameters of all samples, such as SBET, VBJH and dpore decrease with the increase in burn-off rate. SEM results also present the similar rules and agree well with those determined with N2 adsorption method. Findings of present research might have important implications for better understanding of the relationship between pore structure and combustion characteristic of pulverized coal in the O2/CO2 environment.

关 键 词：O2/CO2气氛 煤粉燃烧 N2吸附 孔隙结构 扫描电镜 

分 类 号：TQ534.9[化学工程—煤化学工程]