Coal and gas are two important resources in China,and it is an effective way to recycle them with the method of co-extraction of coal and gas.In view of actual situation of China's co-extraction of coal and gas,th...Coal and gas are two important resources in China,and it is an effective way to recycle them with the method of co-extraction of coal and gas.In view of actual situation of China's co-extraction of coal and gas,this research adopts the science evaluation of gas extraction of coal by the method of quantitative evaluation,and preliminarily establishes the technical evaluation system of co-extraction of coal and gas.Technical evaluation system of co-extraction of coal and gas includes safety evaluation,economic evaluation and resource recovery evaluation in the process of mining coal and gas.In addition,this paper results in the selected evaluation parameters and target functions that are used in the three evaluation methods.The establishment of evaluation system for co-extraction of coal and gas plays an important theoretical significance and guiding role in co-extraction of coal and gas for China's coal enterprises.展开更多
Boiler fan is the main power consumption device in thermal power units and the induced draft fan accounted for the largest proportion. Reducing the energy consumption rate of induced draft fan is the main path to redu...Boiler fan is the main power consumption device in thermal power units and the induced draft fan accounted for the largest proportion. Reducing the energy consumption rate of induced draft fan is the main path to reduce the power consumption rate of thermal power units. The induce fan driven by small turbine is greatly effective for reducing the power consumption rate and the supply coal consumption rate in large thermal power plant. Take 1000 MW power units for example, the selection of steam source for steam turbine were discussed and economic performance of the unit under different steam source was compared in this paper. The result shows that compared with the motor driven method, there is about 1.6 g/kWh decrease in supply coal consumption rate driven by the fourth stage extraction steam;whereas there is about 2.5 g/kWh decrease in supply coal consumption rate driven by the fifth stage extraction steam.展开更多
Mineable coal reserves in thick and extra-thick seams account for 44% of the total deposit in China. Fullymechanized top-coal caving technology is a new mining method of safe and efficient underground operations in ex...Mineable coal reserves in thick and extra-thick seams account for 44% of the total deposit in China. Fullymechanized top-coal caving technology is a new mining method of safe and efficient underground operations in extra-thick seams in China. The development of fullymechanized top-coal caving technology in China, which was successfully applied in Face 8105 in Tashan Coal Mine, Datong, Shanxi, China, is analyzed in this paper.Studies on movement pattern of top-coal and roof from fully-mechanized top caving face in 14–20 m extra-thick seams have been carried out. A series of key technologies were successfully developed, including strata control technology, equipment for high-efficient and high-recovery top caving operations, and safety guarantee technology for low gas occurrence and high gas emission. As a result, the fully-mechanized top-coal caving Face 8105, with large mining height in Tashan Coal Mine, has achieved a recovery rate of 88.9% and an average equipment operation rate of 92.1%. With coal production of 10.84 Mt in 2011,the demonstration project is a technology and equipment breakthrough for fully-mechanized top-coal caving face in extra-thick coal seams with large mining height.展开更多
基金supported by the State Key Basic Research Program of China(No.2011CB201206)the Major Projectof the National Science and Technology of China(No.2011ZX05040-005)the National Natural Science Foundation of Youth Science Foundation(No.50904033)
文摘Coal and gas are two important resources in China,and it is an effective way to recycle them with the method of co-extraction of coal and gas.In view of actual situation of China's co-extraction of coal and gas,this research adopts the science evaluation of gas extraction of coal by the method of quantitative evaluation,and preliminarily establishes the technical evaluation system of co-extraction of coal and gas.Technical evaluation system of co-extraction of coal and gas includes safety evaluation,economic evaluation and resource recovery evaluation in the process of mining coal and gas.In addition,this paper results in the selected evaluation parameters and target functions that are used in the three evaluation methods.The establishment of evaluation system for co-extraction of coal and gas plays an important theoretical significance and guiding role in co-extraction of coal and gas for China's coal enterprises.
文摘Boiler fan is the main power consumption device in thermal power units and the induced draft fan accounted for the largest proportion. Reducing the energy consumption rate of induced draft fan is the main path to reduce the power consumption rate of thermal power units. The induce fan driven by small turbine is greatly effective for reducing the power consumption rate and the supply coal consumption rate in large thermal power plant. Take 1000 MW power units for example, the selection of steam source for steam turbine were discussed and economic performance of the unit under different steam source was compared in this paper. The result shows that compared with the motor driven method, there is about 1.6 g/kWh decrease in supply coal consumption rate driven by the fourth stage extraction steam;whereas there is about 2.5 g/kWh decrease in supply coal consumption rate driven by the fifth stage extraction steam.
文摘Mineable coal reserves in thick and extra-thick seams account for 44% of the total deposit in China. Fullymechanized top-coal caving technology is a new mining method of safe and efficient underground operations in extra-thick seams in China. The development of fullymechanized top-coal caving technology in China, which was successfully applied in Face 8105 in Tashan Coal Mine, Datong, Shanxi, China, is analyzed in this paper.Studies on movement pattern of top-coal and roof from fully-mechanized top caving face in 14–20 m extra-thick seams have been carried out. A series of key technologies were successfully developed, including strata control technology, equipment for high-efficient and high-recovery top caving operations, and safety guarantee technology for low gas occurrence and high gas emission. As a result, the fully-mechanized top-coal caving Face 8105, with large mining height in Tashan Coal Mine, has achieved a recovery rate of 88.9% and an average equipment operation rate of 92.1%. With coal production of 10.84 Mt in 2011,the demonstration project is a technology and equipment breakthrough for fully-mechanized top-coal caving face in extra-thick coal seams with large mining height.
