检索结果-南通市图书馆

Experimental study on the coupling effect of pore-fracture system and permeability controlled by stress in high-rank coal

在线全文

学校读者我要写书评

暂无评论

Frontiers of Earth Science 2023年第1期17卷 135-144页

作者： Jiang HAN caifang wu Lu CHENG Key Laboratory of Coalbed Methane Resources and Reservoir Formation(Ministry of Education of China) China University of Mining and TechnologyXuzhou 221116China School of Resources and Geoscience China University of Mining and TechnologyXuzhou 221116China China United Coalbed Methane Corporation Ltd.Beijing 100016China

During the coalbed methane(CBM)exploitation,the reservoir permeability can be affected by the effective stress that varies with the reservoir fluid pressure,which is a complex,dynamic and significant engineering *** analyze the response characteristics of the pore-fracture system by the changing stress,this work simulated reservoir and fluid pressures during the exploitation by adjusting confining pressure and displacement *** sensitivity experiments under different effective stresses were conducted to systematically study the stage variation characteristics of porosity and permeability of *** results show that the permeability decreases exponentially with the increase in effective stress,consistent with previous ***,the porosity shows a V-shaped trend,which is different from the traditional understanding that it would decrease continuously with rising effective *** variation characteristics(of porosity and permeability above)therefore result in a phased porosity sensitivity of coal permeability(PPS).Moreover,the stress sensitivity of the samples was evaluated using the permeability damage rate method(MPDR)and the stress sensitivity coefficient method(MCSS),both of which showed that it ranges from the degree of strong to extremely *** the effective stress is lower than 5–6 MPa,the stress sensitivity of the coal reservoir drops rapidly with effective stress rising;when it is higher than 5–6 MPa,the change in stress sensitivity tends to flatten out,and the stress sensitivity coefficient(CSS)goes down slowly with rising effective ***,suggestions are proposed for the drainage scheme of CBM wells based on the experimental results.

关键词： stress sensitivity porosity sensitivity permeability high-rank coal effective stress

Stratum energy of coal-bed gas reservoir and their control on the coal-bed gas reservoir formation

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2007年第9期50卷 1319-1326页

作者： wu caifang QIN Yong FU XueHai Department of Earth Resources and Geosciences China University of Mining & Technology Xuzhou 221008 China Department of Earth Resources and Geosciences China University of Mining & Technology Xuzhou 221008 China Department of Earth Resources and Geosciences China University of Mining & Technology Xuzhou 221008 China

Stratum energy of coal-bed gas reservoir, including coal-radix flexibility energy, groundwater flexibility energy and gas flexibility energy (hereinafter "three energy"), depends on the energy homeostasis system, the core process of which is the effective transfer of energy and the geological selective process. Combining with the mechanics experimentations of coal samples, different flexibility energy has been analyzed and researched quantificationally, and a profound discussion to their controls on the coal-bed gas reservoir formation has been made. It is shown that when gas reservoir is surrounded by edge water and bottom water, the deposited energy in the early phase of forming gas reservoir is mostly coal-radix and gas flexibility energy, but the effect of groundwater flexibility energy increases while water-body increases. The deposited energy in the middle and later phase of forming gas reser voir is mostly gas flexibility energy, which is greater than 80% of all deposited energy. In the whole process, larger groundwater body exerts greater influences on gas accumulation. The paper indicated that higher stratum energy is more propitious to forming coal-bed gas reservoir. And higher coal-radix flexibility energy and gas flexibility energy are more propitious to higher yield of gas reservoirs, while higher groundwater flexibility energy is more propitious to stable yield of gas reservoirs. Therefore, the key to evaluating the coal-bed gas reservoir formation is the stratum energy of coal-bed gas reservoir.

关键词： coal-bed reservoir, flexibility energy, coal-radix flexibility energy, groundwater flexibility energy, gas flexibility energy, coal-bed gas reservoir formation

Interlayer interference mechanism of multi-seam drainage in a CBM well:An example from Zhucang syncline

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2016年第6期26卷 1101-1108页

作者： Jiang Wei wu caifang Wang Qiao Xiao Zhenghui Liu Yang Hunan Provincial Key Laboratory of Shale Gas Resource Utilization Hunan University of Science and Technology Institute of Geology School of Civil EngineeringHunan University of Science and Technology School of Resource & Geoscience China University of Mining and Technology

Based on the characteristics of the strong volatility of physical property in vertical direction, high gas content, high resource abundance and large exploitation potentiality of coal reservoir in Bide-Santang basin of Zhina coal field, we study the generation mechanism of interlayer interference, propagation rules of reservoir pressure drop and influencing factors of gas productivity in CBM multi-seam drainage in the paper. On the basis of the actual production data of X-2 well of Zhucang syncline in Bide-Santang basin,by simulating the gas production process of a CBM well under the condition of multiple seam with COMET3 numerical simulation software, we analyze the influencing factors of gas productivity during the process of multi-seam drainage, and illuminate the interlayer interference mechanism of multiseam drainage. The results show that permeability, reservoir pressure gradient, critical desorption pressure and fluid supply capacity of stratum have great influence on gas productivity of multi-seam drainage while coal thickness has little influence on it. Permeability, reservoir pressure gradient and fluid supply capacity of stratum affect the propagation velocity of reservoir pressure drop and thereby affect the final gas productivity. Moreover, the influence of critical desorption pressure on gas productivity of multiseam drainage is reflected in the gas breakthrough time and effective desorption area.

关键词： Zhucang syncline CBM Multi-seam drainage Interlayer interference Influencing factors

Combined control of fluid adsorption capacity and initial permeability on coal permeability

在线全文

学校读者我要写书评

暂无评论

International Journal of Coal Science & Technology 2022年第6期9卷 127-137页

作者： Xiaolei Liu Jianping Wei Guoying Wei caifang wu Cao Liu Xiaoming Ni State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic University454000 JiaozuoHenanChina College of Safety Science and Engineering Henan Polytechnic University454000 JiaozuoHenanChina State Collaborative Innovation Center of Coal Work Safety and Clean-efficiency Utilization 454000 JiaozuoHenanChina Key Laboratory of Coalbed Methane Resource and Reservoir Formation Process Ministry of EducationSouth Jiefang Road221008 XuzhouJiangsuChina Collaborative Innovation Center of Coalbed Methane(Shale Gas)in Central Plains Economic Zone 454000 JiaozuoChina

The variations of strain and permeability of coal were systematically studied through the physical simulation of N2 and water *** effects of fluid adsorption capacity and initial permeability on strain,permeability and the dominant effect of pore pressure were *** adsorption strain and strain rate of coal during water injection are significantly higher than those during N2 *** edge of free adsorption exists in the early phase of N2 and water injection,which is related to fluid *** this boundary,the strain rate and pore pressure are ***,the injec-tion time of initial stage accounts for about 20%of the total injection time,but the strain accounts for 70%of the total *** water injection,this boundary is about half of water saturation of ***,the influence of pore pressure on permeability is complex,which is controlled by adsorption capacity and initial permeability of *** the initial permeability is large enough,the effect of adsorption strain on permeability is relatively weak,and the promoting effect of pore pressure on fluid migration is ***,the permeability increases with increasing pore *** the initial permeability is relatively low,the pore pressure may have a dominant role in promoting fluid migration for the fluid with weak adsorption ***,for the fluid with strong adsorption capacity,the adsorption strain caused by pore pressure may play a leading role,and the permeability reduces first and then ascends with increasing pore pressure.

关键词： Initial permeability Adsorption capacity Free adsorption Pore pressure Coal strain

Self-adjusted elastic action and its CBM pool-forming effect of the high rank coal reservoir

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2005年第S1期50卷 99-103页

作者： QIN Yong FU Xuehai wu caifang FU Guoyou BU Yingying Institute of Mineral Resources and Geoscience China University of Mining&TechnologyXuzhou 221008China

The coal reservoir is a kind of geologic body with considerable elasticity, and its response to stress is more sensitive than the routine ones. In the pool-forming process of the coalbed methane, (CBM) the action of many external geodynamic factors in the coal reservoir is represented by the ability of CBM’s diffusion and migration in the coal reservoir. Therefore, the occurrence of the natural fissures in the coal reservoir becomes a key that determines whether the CBM pool can be formed or not. Based on the principle, the authors have designed a comprehensive method of physical modeling to study the elasticity of the coal matrix block with different coal ranks in the light of the solid to fluid coupling, have established the model of the volume deformation (self-adjusted elastic effect) of the coal reservoir under the condition of the effective stress-adsorption/desorption, and have obtained a correct understanding of the law of the elastic deformation. Afterwards, a new viewpoint, named as the self-closing elastic effect for forming the CBM pool in the high rank reservoir, is put forward, providing an initial point and a scientific basis for a further investigation into its dynamic factors, possible mechanism and role in the CBM energy-balancing system.

关键词： coalbed methane reservoir elasticity self-adjusted action pool-forming effect.

Effective migration system of coalbed methane reservoirs in the southern Qinshui Basin

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2014年第12期57卷 2978-2984页

作者： wu caifang QIN Yong ZHOU LongGang School of Resource and Earth Sciences China University of Mining & Technology Key Laboratory of CBM Resource and Formation History Ministry of Education

Effective migration system of coalbed methane(CBM)reservoir,which was controlled by development degree and opening-closing degree of fractures,determines the permeability of coal reservoir and can be characterized by the pore-fracture system in the extrinsic *** this paper,based on coal matrix elastic self-regulating effect theory and coal reservoir combined elastic energy theory,the fracture opening-closing degree parameterΔand the fracture development degree parameterξare suggested for the quantitative study of the effective migration system of CBM reservoir in southern Qinshui ***,the control functions ofξandΔto CBM enrichment and high production are *** results show that in present stage the area with highξvalue is located in Anze and Qinyuan,and then Zhengzhuang and Fangzhuang,where fracture development degree is *** area with highΔvalue is located in Zhengzhuang and Fanzhuang,and then Anze and Qinyuan,indicating where coal matrix elastic self-regulating positive effect dominates and fractures tend to be *** the comprehensive analysis onξandΔ,it can be found that their best match area is located in Zhengzhuang and Fanzhuang,with high values for fracture development degree and opening-closing degree probably bringing about high fluid pressure and good permeability of reservoirs,which are advantageous to an abundant CBM production.

关键词： CBM reservoirs effective migration system opening-closing degree of fracture development degree of fracture permeability

同方期刊数据库

煤炭地下气化过程中温度场及其传热特征研究进展

在线全文

学校读者我要写书评

暂无评论

煤炭科学技术 2022年第1期50卷 275-285页

作者：吴财芳蒋秀明中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221116 中国矿业大学资源与地球科学学院江苏徐州221116

煤炭地下气化(UCG)技术作为一种环境友好的采煤方法,可被用来开发深部煤层与矿井遗留的煤炭资源。当地下气化时,随着气化时间的推移,煤炭在煤层内部"燃烧"逐渐形成气化炉,炉内温度最高可达1200℃。从UCG过程中的放热反应出发,综述了热... 详细信息

煤炭地下气化(UCG)技术作为一种环境友好的采煤方法,可被用来开发深部煤层与矿井遗留的煤炭资源。当地下气化时,随着气化时间的推移,煤炭在煤层内部"燃烧"逐渐形成气化炉,炉内温度最高可达1200℃。从UCG过程中的放热反应出发,综述了热量来源、温度场的变化及其传热特征等,总结了研究温度场的重要手段。分析认为,UCG是一个复杂的温热动态变化过程,在此过程中氧化还原反应、吸热和放热的可逆反应同时进行,导致了气化炉的温度场及其传热机制的复杂性。研究气化过程传热机制的方法主要有物理模拟、试验监测、理论计算和数值模拟4种,各自具有不同的适应性。其中,物理模拟的可操控性强,但是难以解决地层接触关系导致的接触热阻误差;试验监测能真实反映温度场等的变化情况,但是实际操作的经济性差;理论计算通过对气化过程的拆分,从理论角度定性定量了UCG的温度场特征,但理论计算难以考虑到温度渗流等对温度的影响;数值模拟借助计算机进行温度场的多场耦合,综合考虑了渗流、变形、温度等对传热的影响,但多场的物理耦合计算难度较大,且煤层及岩石的热物理性质随温度变化会产生较大的差异,导致数值建模的计算难度增加,制约了数值模拟方法的应用。综上所述,现有的UCG温度场的研究手段难以真实反映出气化炉的传热特征,各种研究方法只能研究特定情况下的温度变化,难以与实际情况结合。因此,基于现场试验数据,结合大型物理模拟试验与数值模拟手段,开展多物理场之间的耦合机理研究是后续煤炭地下气化的主要研究方向。另外,岩石热物理性质在高温下的变化规律及其对温度场的影响作用,也将是值得重视的研究方向之一。

关键词：煤炭地下气化温度场数值模拟多场耦合岩石热物理性质

基于时间序列BP神经网络的煤层气井排采制度优化

在线全文

学校读者我要写书评

暂无评论

中国矿业大学学报 2015年第1期44卷 64-69页

作者：吴财芳姚帅杜严飞中国矿业大学资源与地球科学学院江苏徐州221008 中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221008

为了准确预测煤层气井产能,定量分析和优化煤层气井排采制度,利用神经网络具有的非线性映射能力和预测能力,基于时间序列思想构建了结构为14-13-7的BP神经网络煤层气井产能预测模型,在不同排采制度下对潘庄区块CM1井进行了未来7d的产能... 详细信息

为了准确预测煤层气井产能,定量分析和优化煤层气井排采制度,利用神经网络具有的非线性映射能力和预测能力,基于时间序列思想构建了结构为14-13-7的BP神经网络煤层气井产能预测模型,在不同排采制度下对潘庄区块CM1井进行了未来7d的产能预测.结果表明:依据产水量、井底流压调控量度临界值分别为0.2 m3/d,0.1MPa,可以设计24种排采制度调整方案.其中,使产气量大幅减小的排采制度调整方案有5种,小幅减小的有7种,小幅增大的有7种,大幅增大的有5种.可以根据未来生产需要,采取不同的排采制度,对煤层气井产能实现人工实时调控.

关键词：时间序列 BP神经网络排采制度煤层气井优化

滇东黔西多煤层地区煤层气“层次递阶”地质选区指标体系构建

在线全文

学校读者我要写书评

暂无评论

煤炭学报 2018年第6期43卷 1647-1653页

作者：吴财芳刘小磊张莎莎中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221008 中国矿业大学资源与地球科学学院江苏徐州221008

针对滇东黔西多煤层、高地应力和构造复杂等地质特点,在明确提出煤层气地质选区过程中的有利区、甜点区和甜点段概念的基础上,阐明了3者之间"层次递阶"的关系。有利区指从滇东黔西的众多次级向斜中优选有利向斜,甜点区指从有利向斜中优... 详细信息

针对滇东黔西多煤层、高地应力和构造复杂等地质特点,在明确提出煤层气地质选区过程中的有利区、甜点区和甜点段概念的基础上,阐明了3者之间"层次递阶"的关系。有利区指从滇东黔西的众多次级向斜中优选有利向斜,甜点区指从有利向斜中优选煤层气开发"靶区",甜点段是在煤层气开发"靶区"内从垂向上优选组合层段。针对研究区次级向斜多,勘探程度差异大,许多参数无法统一的特点,在有利区优选指标体系中提出了煤层气地质资源量、地质资源丰度和可采资源量相结合的关键指标,煤层气地质资源量和地质资源丰度为一票否决指标;针对研究区构造复杂和高地应力的特点,在甜点区优选指标体系中提出了断层分维值、构造曲率及埋深相结合的关键指标,断层分维值为一票否决指标;针对研究区多煤层发育,易诱发层间干扰的特点,在甜点段优选指标体系中提出了煤体结构、临界解吸压力差和储层压力梯度差相结合的关键指标,煤体结构为一票否决指标;并在各个阶段均提出了相应的参考指标,最终构建了针对研究区特点具有区域特色的煤层气地质选区指标体系。

关键词：滇东黔西有利区甜点区甜点段指标体系