Mechanism And Economy Research On Thermal-Pressure Dewatering For East Of Inner-Mongolia Lignite

Lignite resource which is plenty stored in the east of Inner-Mongolia cannot be economically used by long distance transportation and economically and safely used in power plants due to its high moisture as well as low heat value. But as the world energy crisis and domestic coal shortage, each of big power plant purchases lignite to instead of bituminous by the method of blending. So it is significantly to expand the economy utilization area by dewatering the moisture of the lignite by economy and effective method.Lignite thermal-pressure dewatering means to simulate the coal-forming process, in specific temperature and pressure, the internal structure of lignite changes and the moisture decreases, the characteristics of lignite approaches bituminous as its heat value increases. Due to the dewatering process is under high pressure, the moisture in lignite separates out in liquid, so that the energy consumption relatively lower. Furthermore, this dewatering method has good application prosperity because the dewatered lignite has restraint effective to water re-absorption.This thesis in connection with thermal-pressure dewatering technical, determined the work condition for dewatering by thermal analysis and et al. dewatered lignite can be getted by thermal-pressure the Dayan lignite form east of the Inner-Mongolia through experimental bench. The moisture in lignite decreases significantly under different pressure dewatering. The total moisture decreased by 75% and the heat value increased by 25%. The thermal-pressure dewatering has certain effective in restraint its water re-absorption. Used SEM to analysis thermal-pressure dewatered lignite, the surface of dewatered lignite got smooth and the gully structure disappeared. The low-temperature nitrogen absorption test shows the pore size distribution dewatered under higher pressure changed and the total pore volume decreased. The dewatered lignite shows its'economic in long transportation and power plants combustion.