Pilot Plant Study on Pyrolysis of Pulverized Coal in Circulating Fluidized Bed with Heat Char Carrier

Pilot plant study on pyrolysis of pulverized coal in circulating fluidized bed with heat char carrier

Pengfei Dong, Zhiping Zhu^*, Guangjun Meng, Qinggang Lu, Kuangshi Yu

Institue of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China

Abstract:

The high dust content and poor quality of tar are the main restriction for industrialization development of pulverized coal pyrolysis. A hierarchical dedusting process, mainly consisting of dust removal of pulverized coal and heat char carrier, dust removal during pyrolysis reaction and dust removal of pyrolysis products, has been proposed by institute of engineering thermophysics (IET), Chinese Academy of Sciences (CAS) to reduce the dust content of tar in the pyrolysis of pulverized coal. Using heat char as solid heat carrier promotes the heavy components of tar cracking, which is beneficial to upgrade the quality of the tar so as to get more high-value light tar boiling points below 360 ¡æ. Experiments on pyrolysis of Chinese Shenmu pulverized coal (with the range of particle size: 0¡«10mm) were carried out in a pilot plant with a treating capacity of 10 t/h. The effects of hierarchical dedusting on dust content and tar composition were investigated. It was found that the dust content decreases by hierarchical dedusting. When temperature is 700 ¡æ with coal feeding rate of 10 t/h, the dust content of tar reaches the minimum value of 4.12 wt%, and the light tar content of tar reaches the highest value of 86 wt%.

Keywords: circulating fluidized bed; pulverized coal pyrolysis; hierarchical dedusting

Acknowledgements:

This work was financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDA07010300).