Secondary reactions and diffusion of tar during single coal particle pyrolysis
ZHANG Shengcheng, HE Rong
Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084, China
Abstract：A numerical model was developed to investigate the tar production during pyrolysis of a single coal particle. The model was based on the fragmentation and diffusion (FD) coal pyrolysis model and considered the secondary reactions and diffusion inside the coal particle. The model was validated by pyrolysis experiments in a drop-tube furnace and then used to investigate the influences of the final temperature, heating rate and particle diameter. The results show that the competition between the secondary reactions and tar diffusion greatly influences the tar production. Increases of the final temperature and the heating rate improve both the tar secondary reactions and the diffusion while increasing the particle diameter improves the tar secondary reactions and hinders the diffusion. The final tar yield decreases with increasing final temperature, increasing heating rate and increasing particle diameter.
张盛诚, 何榕. 单颗粒煤粉热解时焦油的二次反应和扩散[J]. 清华大学学报（自然科学版）, 2016, 56(6): 605-610.
ZHANG Shengcheng, HE Rong. Secondary reactions and diffusion of tar during single coal particle pyrolysis. Journal of Tsinghua University(Science and Technology), 2016, 56(6): 605-610.
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2016, Vol. 56 
