The filtration and dewatering of fine clean coal not only ensure industrial water recycle in coal washing plant,but also reduce the moisture of coal product in order to meet the requirements of combustion or coking in...The filtration and dewatering of fine clean coal not only ensure industrial water recycle in coal washing plant,but also reduce the moisture of coal product in order to meet the requirements of combustion or coking industry.Fine clean coal is mainly composed by organic matter,and the property difference of different organic matter determines the filtration and dewatering behavior.In this investigation,vitrinite and inertinite were separated from a clean bituminous coal,and the comparative filtration and dewatering behavior of vitrinite and inertinite were conducted.The results showed that inertinite has lower dewatering rate and higher filter cake moisture than vitrinite.The analysis of filter cake structure showed that inertinite particle is easier to be broken into small particles due to the difference of mechanical properties,thus forming more compact filter cake than vitrinite.The analysis of particle surface properties showed that vitrinite is more hydrophobic than inertinite,which makes water easier drained from filter cake.The simulation study showed that the structure of inertinite is more porous than that of vitrinite,and the interaction between inertinite and water is stronger than that between vitrinite and water.This study provides a theoretical basis for improving coal dewatering by selectively improving coal maceral hydrophobicity.展开更多
Four types of coals, KL, XB, ZS and GD with different coal ranks, were dissolved with the organic solvent N-methyl-2- pyrrolidone at 350 ℃ and around 3.0 MPa pressure to obtain thermal soluble constituents （TSCs）. ...Four types of coals, KL, XB, ZS and GD with different coal ranks, were dissolved with the organic solvent N-methyl-2- pyrrolidone at 350 ℃ and around 3.0 MPa pressure to obtain thermal soluble constituents （TSCs）. The yield, component and maceral group were investigated as well as their coking properties, including caking index and thermoplasticity. The results indicated that the yields of the four coals were of the following order： KL 〉 XB 〉 ZS 〉 GD. Based on the yield and the vitrinite content, coals were ranked from high to low. The ash contents of TSCs were significantly less than that of raw coals, and the TSCs contain more light components, leading to an increase in volatile matter. The patterns of Fourier transform infrared spectroscopy indicated that carbonyl was enriched in TSCs. Regarding the maceral group, TSCs were mainly composed of vitrinite which is the main reactive material and converts into binder phase in cokemaking process. Higher caking index values and fluidity were obtained in TSCs compared with the raw coals. The coking experiments with different amounts of TSCs addition were carried out. The results demonstrated that the proper TSCs addition could enhance the coke strength due to its high caking index and good fluidity.展开更多
基金supported by the National Natural Science Foundation of China(U2003125)。
文摘The filtration and dewatering of fine clean coal not only ensure industrial water recycle in coal washing plant,but also reduce the moisture of coal product in order to meet the requirements of combustion or coking industry.Fine clean coal is mainly composed by organic matter,and the property difference of different organic matter determines the filtration and dewatering behavior.In this investigation,vitrinite and inertinite were separated from a clean bituminous coal,and the comparative filtration and dewatering behavior of vitrinite and inertinite were conducted.The results showed that inertinite has lower dewatering rate and higher filter cake moisture than vitrinite.The analysis of filter cake structure showed that inertinite particle is easier to be broken into small particles due to the difference of mechanical properties,thus forming more compact filter cake than vitrinite.The analysis of particle surface properties showed that vitrinite is more hydrophobic than inertinite,which makes water easier drained from filter cake.The simulation study showed that the structure of inertinite is more porous than that of vitrinite,and the interaction between inertinite and water is stronger than that between vitrinite and water.This study provides a theoretical basis for improving coal dewatering by selectively improving coal maceral hydrophobicity.
基金This work was financially supported by the National Natural Science Foundation of China （Grant No. 51574023） and National Key Research and Development Program of China （2016YFB0600701）.
文摘Four types of coals, KL, XB, ZS and GD with different coal ranks, were dissolved with the organic solvent N-methyl-2- pyrrolidone at 350 ℃ and around 3.0 MPa pressure to obtain thermal soluble constituents （TSCs）. The yield, component and maceral group were investigated as well as their coking properties, including caking index and thermoplasticity. The results indicated that the yields of the four coals were of the following order： KL 〉 XB 〉 ZS 〉 GD. Based on the yield and the vitrinite content, coals were ranked from high to low. The ash contents of TSCs were significantly less than that of raw coals, and the TSCs contain more light components, leading to an increase in volatile matter. The patterns of Fourier transform infrared spectroscopy indicated that carbonyl was enriched in TSCs. Regarding the maceral group, TSCs were mainly composed of vitrinite which is the main reactive material and converts into binder phase in cokemaking process. Higher caking index values and fluidity were obtained in TSCs compared with the raw coals. The coking experiments with different amounts of TSCs addition were carried out. The results demonstrated that the proper TSCs addition could enhance the coke strength due to its high caking index and good fluidity.
