Study On Drying The Low Rank Coal By Hydrothermal Method

This paper selects Inner Mongolia as the main research object Erdos lignitelow rank coal, using the high pressure reaction kettle on the hydrothermal dryingresearch，the effectsof different drying temperatures, coal particle size, drying time onits drying behavior, and hydrothermal upgrading coal samples breath test, Measuredby themercury, nitrogen adsorption and other equipment on the pore structure ofcoalsamples before and after drying, coal properties and other physical and chemicalproperties were characterized.Through the analysis of the drying and relapse of the data, the results show that During the drying process, with increasing the temperature and time ofdrying efficiency are coal increases, the degree of destruction of the pore structure also will enhance, promote removal of water from the pores, at190℃drying efficiency have more than90%.upgraded coal samples relapse behavior withincreasing drying temperature and extend the drying time showed a decreasing trend after the first increase. drying and relapse test results show that the hydrothermal synthesis temperature of190℃drying drying efficiency is best suitable drying time of20min. for the coal particle size, the drying efficiency andrelapse decreases efficiency has improved granularity, but the effect is not asdramatic temperature and time, and the smaller the particle size required to obtain more energy to achieve the desired size, so the particle size range of0.2-0.8mm.Analysis showed that the physical and chemical properties of coal samplefor quality improvement, in the initial stage of drying, the surface structure of coal has been destroyed, the expansion cracking phenomenon began to appear, macroporous first collapse fragments intosmaller pore structure of coal, the increase of the specific surface area and porosity. by comparing the amount of pore structureand relapse change, improve the quality of the pore structure of coal samples for relapse behavior has a significant impact. for upgrading the quality characteristics of coal sample analysis showed that low rank coal rank after hydrothermal upgrading has improved.