Sung Min Yoon  Seok Hyeong Lee  Tae Hwi An  Myung Won Seo  Sang Won Lee  Dae Sung Kim  Tae-Young Mun  Sung Jin Park  Sang Jun Yoon  Ji Hong Moon  Jae Goo Lee  Jong Hoon Joo  Ho Won Ra

10.7464/ksct.2023.29.4.288

Coal Devolatilization Spontaneous combustion Regression Analysis

Coal is abundantly available compared to other energy sources and is used as a versatile energy resource worldwide. To address the environmental issues stemming from conventional coal utilization, efforts are underway to develop clean coal utilization technologies, with IGCC technology being a notable example. In IGCC plants, coal is subjected to a CMD process where both drying and pulverization are achieved by supplying hot air. However, if the temperature of the supplied hot air is excessively high, it can lead to devolatilization and spontaneous combustion, thereby compromising the stable operation of the CMD process. This study aimed to measure the devolatilization and spontaneous combustion temperatures of different types of bituminous coal, and to explore their correlations with the characteristics of the coals. Six coal types exhibited devolatilization between 350 and 400 o C, while three coal types showed devolatilization at temperatures exceeding 400 o C. Spontaneous combustion occurred in one coal type below 100 o C, six coal types between 100 and 150 o C, and two coal types above 150 o C. The measured initiation temperatures were compared with the coal characteristics including the oxygen, moisture, Fe2O3, and CaO content, the H/C ratio, and the O/C ratio to establish correlations. Regression analysis was used to calculate the regression coefficients and determination coefficients for each ignition temperature. It was found that 52.44% of the FC/VM data significantly influenced the volatile matter ignition temperature, and 59.10% of the Fe2O3 data significantly affected the spontaneous combustionignition temperature.