Study on pore structure characteristics of Indonesian lignite during low temperature drying process.

In order to study the effect of temperature on the pore structure of lignite, liquid nitrogen adsorption and scanning electron microscopy (SEM) were used to analyze the change of pore structure of Indonesian lignite after heating, and the relationship between fractal dimension and pore structure of lignite after heating was analyzed. The effect of drying temperature on the pore structure of lignite was investigated by effective moisture diffusion coefficient and X-ray diffraction (×RD). The results show that between 40 and 160 ℃, with the increase of drying temperature, the N2 adsorption and desorption of Indonesian lignite shows a trend of first increasing and then decreasing. The fractal dimensions D1 and D2 of some lignites have a linear relationship with the specific surface area and average pore diameter, respectively, and the fractal dimension D3 has a linear relationship with the average pore diameter. As the drying temperature increases, the moisture transfer resistance decreases and the effective moisture diffusivity of lignite ( D e f f ) increases accordingly. There is a linear positive correlation between D e f f and the average pore diameter. The increase of the lignite aromatic system and the decrease of the crystallite stacking height have certain effects on the pore structure of lignite. [ABSTRACT FROM AUTHOR]