An investigation of pore structure of blended coal coke produced by pyrolysis of three kinds of coal

Abstract

ABSTRACT Blended coal combustion technology is being adopted by more and more power plants as a clean coal combustion technology, while the combustion of coal coke accounts for more than 85% of the total combustion process of pulverized coal. In order to investigate the effects of different factors on the pore structure and fractal properties of the blended coal coke, a low-temperature nitrogen adsorption method and scanning electron microscopy are used to study the coal coke consisting of three types of coal after pyrolysis. The adsorption isotherm analysis indicates that the pore structure in blended coal coke consisted mainly of semi-open pores with semi-cates. Petroleum coke can severely inhibit microporosity when the content of petroleum coke in the blended coal sample exceeds 10%. The microporosity distribution of blended coal coke with different blending ratios is more concentrated than that of mesopores. In addition, it is found that the trend of D1 is consistent with the trend of the ratio of the microporous specific surface area to the total specific surface area in the blended coal coke. Bituminous coal will make the blended coal coke have a complex structure and petroleum coke will make it have a smooth surface.