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Xu J.,Chongqing University | Peng S.,Chongqing University | Yin G.,Chongqing University | Tao Y.,Henan Provincial Coal Seam Gas Development and Utilization Co. | And 2 more authors.
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2010

A self-developed triaxial servo-controlled seepage equipment for thermo-fluid-solid coupling of coal containing methane is introduced. It is composed of servo-controlled loading system, triaxial compression chamber, water bath with thermostatic control system, interstitial pressure control system, data measuring system and supporting system. The maximum axial pressure is 100 MPa; and the maximum confining pressure is 10 MPa. The heating temperature can reach as high as 100°C; and the dimensions of tested cylinder samples are φ50 mm×100 mm. There are some advantages of the seepage equipment: (1) Tests performed on this equipment can show the comprehensive influence of geostress, gas pressure and temperature up on permeability of coal containing methane. (2) Many kinds of load forms can be completed on this servo-controlled system. (3) Plane-charging can be carried out for the coal sample, which reflects the actual gas source situation of coal bed. (4) An orientation system is designed to insure the accuracy of the data achieved in the tests. (5) By using the sensors, the data are more sensitive and accurate. (6) A large-scale water bath with thermostat-controlled system is designed; and a water circulating pump is also installed. (7) It can be used to study permeability and deformation characteristics of coal containing methane. Experiments on coal containing methane with different confining pressures and different temperatures in the seepage equipment demonstrate that the deformation of coal containing methane has four stages; and the compressive strength increases with the increase of confining pressure. Moreover, the seepage discharge is different in each stage and declines with the increasing of temperature in general. The seepage equipment can be used to study certain scientific law of thermo-fluid-solid coupling seepage of coal containing methane, which can provide fundamental basis for studying gas movement in underground coal seam and gas suction technology. Source

Luo Q.,China University of Petroleum - Beijing | Zhong N.,China University of Petroleum - Beijing | Qin J.,China University of Petroleum - Beijing | Qin J.,National Research Center for Geoanalysis | And 7 more authors.
International Journal of Coal Geology | Year: 2014

Thucholites have mostly been observed in the intergranular pores of sandstones and conglomerates. In this study, investigation of thucholites in Mesoproterozoic shales has been undertaken to explain the origin and maturation of the organic matter. An optical microscope and a scanning electron microscope equipped with an Oxford X-ray energy-dispersive spectrometer (SEM-XDS) were used to study the thucholite in the Hongshuizhuang Formation (1.4. Ga) from the Yanshan Basin of northern north China. The rare and scattered thucholites are present in the shales and do not occur in the dolomites/argillaceous dolomites. The thucholite contains an apparent radioactive mineral particle as the core. The inner rim around the radioactive mineral core generally shows higher reflectance and non-fluorescence, whereas the outer rim displays low reflectance and strong fluorescence. These contrasting observations indicate higher polymerization in the inner rim relative to the outer rim. The mineral grains in the thucholites are mostly monazite and less commonly, zircon. The radioactive mineral grains of granodiorite provenance fell into algal mats at the sediment-water interface through seawater transportation, followed by polymerization of organic matter by ionizing radiation from the radioactive mineral matter through geological time. This process of formation of thucholites in shales is different from that in sandstones and conglomerates. The outer rim of the thucholites shows strong fluorescence, indicating that the thermal maturity of these 1.4. Ga old sediments is still in the oil window, consistent with the low equivalent vitrinite reflectance values (0.82-0.88%) calculated from protobitumen reflectance. The reflectance of the outer rim is close to the average of protobitumen reflectance of the whole sample, suggesting that radioactive heat has limited effect on the thermal maturity of the organic matter. © 2014 Elsevier B.V. Source

Wang J.,Zhengzhou University | Feng L.,Zhengzhou University | Feng L.,Henan Provincial Coal Seam Gas Development and Utilization Co. | Li Z.,Zhengzhou University
Advanced Materials Research | Year: 2012

For the coal resources working which are affected by the coal mine flooding seriously, this paper make an analysis on the factors which affect the coal mine flooding emergency ability evaluation model based on GA-WNN is established through the wavelet neural network value which is optimized with genetic algorithm. This model combined the global optimization ability of genetic algorithm with the time-frequency localization of wavelet neural network. This combination can make up for many defects (for example, the neural network structure should be given artificially, the function can got local minimum easily and so on). Therefore, the local mine flooding emergency ability evaluation model based on genetic algorithm and wavelet neural network have higher reliability and calculation ability, and is beneficial to the pre-control management for coal mine flooding rescue. © (2012) Trans Tech Publications. Source

Wang W.-Z.,University of the Southwest | Tao Y.-Q.,University of the Southwest | Tao Y.-Q.,Henan Provincial Coal Seam Gas Development and Utilization Co. | Xu J.,University of the Southwest | Peng S.-J.,University of the Southwest
Chongqing Daxue Xuebao/Journal of Chongqing University | Year: 2010

To discuss the mechanism of gas pressure in coal and gas outburst process, with the constant of moulding pressure, moisture and forced status of the outburst coal sample, five outburst experiments of the different gas pressure are simulated by the independently developed coal and gas outburst simulation test device and the same coal sample. It is found that coal and gas outburst could produce pyriform or elliptic holes with small mouth and big belly. And the volume of hole to the volume of outburst coal is from 1/2 to 2/3. Moreover, there is a threshold value of gas pressure for coal and gas outburst and greater with the increase of outburst intensity. As the force of outburst, the gas pressure has a certain effect of ejection and porphyrization on the outburst coal powders. The coal sample temperature varies continuously with the trend of rising firstly and decreasing subsequently. And the grads of coal temperature can be adopted for predicting the coal and gas outburst. Source

Wang J.-F.,Zhengzhou University | Feng L.-J.,Zhengzhou University | Feng L.-J.,Henan Provincial Coal Seam Gas Development and Utilization Co. | Zhai X.-Q.,Zhengzhou University
Przeglad Elektrotechniczny | Year: 2012

Flooding emergency capability of coal mine is influenced by personnel's emergency quality, rescue equipment, rescue materials, rescue team and emergency management. This paper sets up a causal diagram and a flow chart model. With investigation on coal enterprises, a simulation model of flooding emergency capacity of coal mine is established using system dynamics. Results show: at the early stage of coal mine production, emergency input has hysteretic nature; increasing emergency input improves each factor's emergency level and flooding emergency capacity of coal mine; initial emergency level affects the time flooding emergency capacity reaches to desired level; the impact of each factor on flooding emergency capacity is different. The simulation model helps a sense of emergency input direction scientifically for coal enterprises. It is good for improving flooding emergency capacity of coal mine. Source

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