In recent years, there have been considerable developments in energy provision with the growing improvements in energy supply security and support systems in China. However, China's energy system continues to reta...In recent years, there have been considerable developments in energy provision with the growing improvements in energy supply security and support systems in China. However, China's energy system continues to retain a high-carbon feature where coal dominates energy production and consumption, which has led to the rapid growth of greenhouse gas emissions and associated serious environmental pollution. It has therefore become an important task for China to consider how to promote the low-carbon development of energy system. This paper summarized the basic trends and challenges for development of low-carbon energy system in China and studied the primary energy consumption and carbon emissions in different scenarios at 10-year intervals between 2010 and 2050. The analysis showed that controlling coal consumption will have an important influence on the control of total carbon emissions and of carbon emission peaking; promotion of non-fossil fuel energies will offer a growing contribution to a low-carbon transition in the medium and long term; the development of carbon capture, utilization, and storage will play a key role in realizing a deep decarbonization pathway, particularly after 2030; and the establishment of a low-carbon power system is crucial for the achievement of low-carbon energy transition. Finally, the strategic considerations and policy suggestions on the development of low-carbon energy systems in China are explored.展开更多
This paper mainly discusses the selection of the technical parameters of fully mechanized top coal caving mining using the neural network technique. The comparison between computing results and experiment data shows t...This paper mainly discusses the selection of the technical parameters of fully mechanized top coal caving mining using the neural network technique. The comparison between computing results and experiment data shows that the set up neural network model has high accuracy and decision making benefit.展开更多
The techniques of stress relief mining in low-permeability coal seams and pillarless gob side retained roadway entry using Y-type ventilation and gas drainage systems were developed to control gas outbursts and applie...The techniques of stress relief mining in low-permeability coal seams and pillarless gob side retained roadway entry using Y-type ventilation and gas drainage systems were developed to control gas outbursts and applied successfully. However, as the mining depth increasing, parts of the gas drainage system are not suitable for mines with high gas emissions. Because larger mining depths cause higher ground stresses, it becomes extremely difficult to maintain long gob side roadways. The greater deformation suffered by the roadway is not favorable lor borehole drilling for continuous gas drainage. To solve these problems, Y-type ventilation and gas drainage systems installed from a roof roadway were designed for drainage optimization. This system was designed based on a gas-enrichment zone analysis developed from mining the 11-2 coal seam in the Zhuji Mine at Huainan, Anhui Province, China. The method of Y-type gas extraction from different mine areas was applied to the panel 1112（1） in the Zhuji Mine. The absolute gas emission rate was up to 116.3 m^3/min with an average flow of 69.1 m^3/min at an average drainage concentration of nearly 85 %. After the Y-type method was adopted, the concentration of gas in the return air was 0.15 %-0.64 %, averaging 0.39 % with a ventilation rate of 2100-2750 m^3/min. The gas management system proved to be efficient, and the effective gas control allowed safe production to continue .展开更多
This paper puts forward the conceptions of semi-flexible units and semi-flexible system, and builds up the theory of semi-flexible output type and repairable production system general reliability analysis and general ...This paper puts forward the conceptions of semi-flexible units and semi-flexible system, and builds up the theory of semi-flexible output type and repairable production system general reliability analysis and general reliability design, which discusses the reliability problems of semi-flexible units and semi-flexible system from three aspects of time, task and capacity.展开更多
In some worldwide hard coal basins recovery of methane from virgin coal beds is difficult. In general,mentioned difficulties are related to geo-mechanical, petrographical and physical-chemical properties of coals in q...In some worldwide hard coal basins recovery of methane from virgin coal beds is difficult. In general,mentioned difficulties are related to geo-mechanical, petrographical and physical-chemical properties of coals in question, occurring for example in the Bowen Basin(Australia) or the Upper Silesian Coal Basin(Poland). Among numerous properties and parameters, the following are very essential: susceptibility of coal beds to deformation connected with coal stress state change and contemporary shrinkage of the coal matrix during methane desorption. Those adverse geo-mechanical and physical-chemical effects are accompanied by essential change of the porous coal structure, which under these disadvantageous conditions is very complex. This study aims to show difficulties, which occur in phase of recognition of the methane-reach coal deposit. Volume absorbed methane(not surface adsorbed) in sub-micropores having minimal size comparable with gas molecule diameter must possess energy allowing separation of the nodes and methane release to micropores.展开更多
Gas drainage in Jincheng Mining Group Co.,Ltd.was introduced briefly and theimportance of gas drainage in gas control was analyzed.Combined with coal-bed gas occurrenceand gas emission,the double system of gas drainag...Gas drainage in Jincheng Mining Group Co.,Ltd.was introduced briefly and theimportance of gas drainage in gas control was analyzed.Combined with coal-bed gas occurrenceand gas emission,the double system of gas drainage was optimized and a progressivegas drainage model was experimented on.For guaranteed drainage,excavationand mining and realization of safety production and reasonable exploitation of gas in coalseams,many drainage methods were adopted to solve the gas problem of the workingface.展开更多
This paper presented a method to create artificial fractures along the existing gas drainage borehole and increase the permeability of the coalbed using a high pressure waterjet cutting system.The field work conducted...This paper presented a method to create artificial fractures along the existing gas drainage borehole and increase the permeability of the coalbed using a high pressure waterjet cutting system.The field work conducted in Rujigou Colliery, Shenhua Ningxia Coal Group demonstrate that the coalbed permeability is increased, and accordingly, gas drainage efficiency is improved up to 3 to 6 times over the traditional methods using high pressure waterjet technique.Also, based on the monitoring data, the conceptual model for gas drainage process associated with different mining activities has been proposed, and few major advantages using waterjet assistance method have been identified.展开更多
There is very low permeability of coal seams in Polish coal mines. For this reason, pre-mining methane drainage is conducted to a small extent, which rarely brings expected results. Methane emission from roof and floo...There is very low permeability of coal seams in Polish coal mines. For this reason, pre-mining methane drainage is conducted to a small extent, which rarely brings expected results. Methane emission from roof and floor sub-economic seams has the greatest share in total methane emission to workings. Effective CMM （coal mine methane） capture is used from goaf in advance or after mining. However, due to longwall mining and ventilation systems, it is not always possible to capture methane from strata. This paper presents a method of increasing the permeability of coal seams and a method of drilling boreholes towards goaf. Initial results of the effectiveness of methane capture after applying these methods are presented.展开更多
文摘In recent years, there have been considerable developments in energy provision with the growing improvements in energy supply security and support systems in China. However, China's energy system continues to retain a high-carbon feature where coal dominates energy production and consumption, which has led to the rapid growth of greenhouse gas emissions and associated serious environmental pollution. It has therefore become an important task for China to consider how to promote the low-carbon development of energy system. This paper summarized the basic trends and challenges for development of low-carbon energy system in China and studied the primary energy consumption and carbon emissions in different scenarios at 10-year intervals between 2010 and 2050. The analysis showed that controlling coal consumption will have an important influence on the control of total carbon emissions and of carbon emission peaking; promotion of non-fossil fuel energies will offer a growing contribution to a low-carbon transition in the medium and long term; the development of carbon capture, utilization, and storage will play a key role in realizing a deep decarbonization pathway, particularly after 2030; and the establishment of a low-carbon power system is crucial for the achievement of low-carbon energy transition. Finally, the strategic considerations and policy suggestions on the development of low-carbon energy systems in China are explored.
基金National Natural Science Foundation of China( 5 97340 90 )
文摘This paper mainly discusses the selection of the technical parameters of fully mechanized top coal caving mining using the neural network technique. The comparison between computing results and experiment data shows that the set up neural network model has high accuracy and decision making benefit.
基金Acknowledgments This work was supported by the National Nat- ural Science Foundation of China （41172147）, the Anhui Province Science and Technology Research Plan （12010402110）, and the Shanxi Province One Hundred Distinguished Professor Plan project.
文摘The techniques of stress relief mining in low-permeability coal seams and pillarless gob side retained roadway entry using Y-type ventilation and gas drainage systems were developed to control gas outbursts and applied successfully. However, as the mining depth increasing, parts of the gas drainage system are not suitable for mines with high gas emissions. Because larger mining depths cause higher ground stresses, it becomes extremely difficult to maintain long gob side roadways. The greater deformation suffered by the roadway is not favorable lor borehole drilling for continuous gas drainage. To solve these problems, Y-type ventilation and gas drainage systems installed from a roof roadway were designed for drainage optimization. This system was designed based on a gas-enrichment zone analysis developed from mining the 11-2 coal seam in the Zhuji Mine at Huainan, Anhui Province, China. The method of Y-type gas extraction from different mine areas was applied to the panel 1112（1） in the Zhuji Mine. The absolute gas emission rate was up to 116.3 m^3/min with an average flow of 69.1 m^3/min at an average drainage concentration of nearly 85 %. After the Y-type method was adopted, the concentration of gas in the return air was 0.15 %-0.64 %, averaging 0.39 % with a ventilation rate of 2100-2750 m^3/min. The gas management system proved to be efficient, and the effective gas control allowed safe production to continue .
文摘This paper puts forward the conceptions of semi-flexible units and semi-flexible system, and builds up the theory of semi-flexible output type and repairable production system general reliability analysis and general reliability design, which discusses the reliability problems of semi-flexible units and semi-flexible system from three aspects of time, task and capacity.
基金sponsored by statutory research University of Science and Technology AGH,Cracow,Poland(No.11 100 281)
文摘In some worldwide hard coal basins recovery of methane from virgin coal beds is difficult. In general,mentioned difficulties are related to geo-mechanical, petrographical and physical-chemical properties of coals in question, occurring for example in the Bowen Basin(Australia) or the Upper Silesian Coal Basin(Poland). Among numerous properties and parameters, the following are very essential: susceptibility of coal beds to deformation connected with coal stress state change and contemporary shrinkage of the coal matrix during methane desorption. Those adverse geo-mechanical and physical-chemical effects are accompanied by essential change of the porous coal structure, which under these disadvantageous conditions is very complex. This study aims to show difficulties, which occur in phase of recognition of the methane-reach coal deposit. Volume absorbed methane(not surface adsorbed) in sub-micropores having minimal size comparable with gas molecule diameter must possess energy allowing separation of the nodes and methane release to micropores.
文摘Gas drainage in Jincheng Mining Group Co.,Ltd.was introduced briefly and theimportance of gas drainage in gas control was analyzed.Combined with coal-bed gas occurrenceand gas emission,the double system of gas drainage was optimized and a progressivegas drainage model was experimented on.For guaranteed drainage,excavationand mining and realization of safety production and reasonable exploitation of gas in coalseams,many drainage methods were adopted to solve the gas problem of the workingface.
文摘This paper presented a method to create artificial fractures along the existing gas drainage borehole and increase the permeability of the coalbed using a high pressure waterjet cutting system.The field work conducted in Rujigou Colliery, Shenhua Ningxia Coal Group demonstrate that the coalbed permeability is increased, and accordingly, gas drainage efficiency is improved up to 3 to 6 times over the traditional methods using high pressure waterjet technique.Also, based on the monitoring data, the conceptual model for gas drainage process associated with different mining activities has been proposed, and few major advantages using waterjet assistance method have been identified.
文摘There is very low permeability of coal seams in Polish coal mines. For this reason, pre-mining methane drainage is conducted to a small extent, which rarely brings expected results. Methane emission from roof and floor sub-economic seams has the greatest share in total methane emission to workings. Effective CMM （coal mine methane） capture is used from goaf in advance or after mining. However, due to longwall mining and ventilation systems, it is not always possible to capture methane from strata. This paper presents a method of increasing the permeability of coal seams and a method of drilling boreholes towards goaf. Initial results of the effectiveness of methane capture after applying these methods are presented.
