Numerical Simulation Of Gas Production For Multilayer Drainage Coalbed Methane Vertical Wells In Southern Qinshui Basin,
2022
Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, Carbon Neutrality Institute, China University of Mining and Technology, Xuzhou 221008, China
Numerical Simulation Of Gas Production For Multilayer Drainage Coalbed Methane Vertical Wells In Southern Qinshui Basin, Liu Shiqi, Fang Huihuang, Sang Shuxun, Hu Qiujia, Duan Weiying, Jia Huimin, Mao Chonghao
Coal Geology & Exploration
With the development of CBM (coalbed methane) exploitation, multilayer drainage of the CBM well has received wide attention. The production control technology is the key to ensure high and stable gas production of CBM well multilayer drainage. However, the complex geological conditions of multiple coal seams increase the difficulty of production control of multilayer drainage. Numerical simulation technology is an effective method to study the production control technology of CBM well multilayer drainage. The scientific and reliable simulation results can provide a basis for production control. In this study, considering the influence of temperature effect, shrinkage effect of coal matrix, …
Mesoscopic Law Of Stress And Fracture Evolution Of Coal Seams Hydraulic Fracturing,
2022
State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China
Mesoscopic Law Of Stress And Fracture Evolution Of Coal Seams Hydraulic Fracturing, Li Quangui, Deng Yize, Hu Qianting, Zhang Yuebing, Song Mingyang, Liu Jichuan, Shi Jialin
Coal Geology & Exploration
Hydraulic fracturing is a technology to increase coal seam permeability, and its stress evolution characteristics and the judgment of fracture morphology and propagation range are particularly important. In this paper, based on directional fracturing, a fluid-structure coupling model of hydraulic fracturing is established by using the discrete element numerical method. The effects of fracturing flow, Poisson’s ratio, natural fracture density on stress evolution and fracture evolution, and their mesoscopic laws are investigated by means of the stress path and crack hot spot diagram. The results show that the stress evolution direction and the final stress path curve shape are obviously …
Stress Sensitivity Characteristics Of Deep Coal Reservoirs And Its Influence On Coalbed Methane Productivity,
2022
School of Resources and Environment, Henan Polytechnic University, Jiaozuo 454003, China; Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization of Henan Province, Jiaozuo 454003, China
Stress Sensitivity Characteristics Of Deep Coal Reservoirs And Its Influence On Coalbed Methane Productivity, Liu Shunxi, Fan Kunyu, Jin Yi, Yu Zhenfeng, Dong Jiabin, Wang Changzheng
Coal Geology & Exploration
Deep coal reservoirs are in a high in-situ stress environment, and their permeability change characteristics are quite different from those of shallow ones. In order to study the effect of the effective stress on the permeability difference of deep coal reservoirs and the characteristics of stress sensitivity anisotropy, the samples from 1 200 m to 1 700 m of the No.15 coal seam in the Hengling block in the Qinshui Basin are taken as the research objects. The overburden porosity and permeability experiments are used to study the permeability changes of parallel and vertical bedding samples under different effective stress …
High-Pressure Jet Disturbance Grouting Technology For Water And Sand Inrush In Roadway Tunneling And Its Application,
2022
Xi’an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi’an 710077, China; Shaanxi Key Laboratory of Preventing and Controlling Technology for Coal Mine Water Hazard, Xi’an 710077, China
High-Pressure Jet Disturbance Grouting Technology For Water And Sand Inrush In Roadway Tunneling And Its Application, Zhao Baofeng, Zhu Mingcheng, Li Debin
Coal Geology & Exploration
In order to control the water and sand inrush in roadway tunneling under weak consolidated formation conditions, taking water and sand inrush during the No.2 coal seam roadway tunneling in Maiduoshan Coal Mine of Ningdong Coalfield as the research object, the problems of large amount of engineering, long period of surface treatment and high risk of underground treatment were solved. The construction of the blocking body at the water and sand inrush point was completed by using the water-retaining wall construction technology, high-pressure jet disturbance grouting technology, the integration of drilling and grouting technology, and the pressure control and slurry …
Influence Of Fracture Types Of Main Roof On The Stability Of Surrounding Rock Of The Gob-Side Coal-Rock Roadway In Inclined Coal Seams And Its Engineering Application,
2022
Mining College, Guizhou University, Guiyang 550025, China; Research Center of Roadway Support and Disaster Prevention Engineering in Coal Industry, China University of Mining and Technology (Beijing), Beijing 100083, China; National & Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas, Guizhou University, Guiyang 550025, China; Guizhou Engineering Center for Safe Mining Technology Under Complex Geologic Condition, Guizhou University, Guiyang 550025, China
Influence Of Fracture Types Of Main Roof On The Stability Of Surrounding Rock Of The Gob-Side Coal-Rock Roadway In Inclined Coal Seams And Its Engineering Application, Gao Lin, Liu Pengze, Zhang Pandong, Wu Guiyi, Kang Xiangtao
Coal Geology & Exploration
Due to the asymmetry and heterogeneity of surrounding rock structure, the surrounding rock of the gob-side coal-rock roadway in inclined coal seams presents more serious deformation and failure under the influence of driving and mining. To reveal the influence of different main roof fracture types on the stability of surrounding rock of the gob-side coal-rock roadway in inclined coal seams, the deformation characteristics of surrounding rock under four main roof fracture types of this kind of roadway are studied by numerical simulation. The results show that the influence degree from highest to lowest of the position of the fracture line …
Research On Dynamic Response Characteristics Of Typical Ground Fissure Sites In Hebei Plain,
2022
School of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, China
Research On Dynamic Response Characteristics Of Typical Ground Fissure Sites In Hebei Plain, Cui Siying, Deng Yahong, Cao Ge, Yu Shuangrui, Mu Huandong, Li Yanjie
Coal Geology & Exploration
Ground fissures in the Hebei Plain are widely distributed and cause severe disasters, seriously impacting local engineering construction and people’s life. The research on ground fissures in the Hebei Plain focuses mainly on the development characteristics, genesis mechanism, and distribution. However, there is little research on the dynamic characteristics of the site in this area. In order to study the influence of ground fissures on the dynamic response of the site in the Hebei Plain, this study conducted microtremor testing on typical earth fissures caused by tectonics, earthquakes, and ancient rivers. It determined the dynamic response characteristics of earth fissure …
Typical Characteristics Of Geological Hazards And Ecological Environment Of Coal Base In The Bends Area Of The Yellow River,
2022
College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; Geological Research Institute for Coal Green Mining, Xi’an University of Science and Technology, Xi’an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi’an 710054, China
Typical Characteristics Of Geological Hazards And Ecological Environment Of Coal Base In The Bends Area Of The Yellow River, Shen Yanjun, Yang Bohan, Wang Shuangming, Kou Haibo, Chen Xing, Xu Yali, Han Senlei
Coal Geology & Exploration
“The ecological protection and high-quality development of the Yellow River Basin” has now been upgraded to a major national strategy. The bends area (the “几” shaped area, also known as the Jiziwan area) is an important part of the Yellow River Basin, and it is also an important gathering area of China’s coal energy. Now the region has six large modern coal bases, coal production accounts for about 40% of the country, in China’s energy security supply security occupies the “ballast” position. However, the region is located in the western arid-semi-arid region, with fragile ecological environment and poor anti-disturbance ability, …
Influence Of Pipeline Crossing On Riverbed Scouring Depth Of Coal Measure Soil,
2022
School of Geosciences and Info-physics, Central South University, Changsha 410083, China; Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, Changsha 410083, China
Influence Of Pipeline Crossing On Riverbed Scouring Depth Of Coal Measure Soil, Wang Xinlong, Sun Pinghe, Zhao Mingzhe, Wang Jingyuan, Xing Shikuan
Coal Geology & Exploration
For the purpose of studying the influence of pipeline crossing on the riverbed scouring depth of the coal measure soil, different pipeline depths, pipe diameters and scouring velocity were set up to carry out scour simulation tests based on the clay and sandy riverbed model test equipment. The SPSS software was used to perform multiple linear regression analysis on the riverbed scouring depth and the above factors. The results show that the pipeline depth, pipe diameter and scouring velocity are responsible for 71.4% to 80.6% of the change of scour depth. The burial depth significantly and negatively affects the scouring …
Techniques For Prevention And Control Of Ordovician Limestone Water Disasters Based On Modified Water Inrush Coefficient Method,
2022
Xi’an Research Institute, China Coal Technology and Engineering Group Corp., Xi’an 710077, China; Shaanxi Provincial Key Lab of Mine Water Disaster Prevention and Control Technology, Xi’an 710077, China
Techniques For Prevention And Control Of Ordovician Limestone Water Disasters Based On Modified Water Inrush Coefficient Method, Li Kai, Li Xiaolong
Coal Geology & Exploration
There are technical problems in preventing and controlling Ordovician limestone water disasters during mining above ultra-thin aquifuges, such as those of the lower coal group in Weibei Coalfield. At Sangshuping Coal Mine, horizontal directional drilling technology was used to develop water prevention and control ideas of Ordovician limestone top utilization and grouting transformation. Firstly, considering the loss of water resistance in the floor failure zone, the water inrush coefficient method was used to determine the critical thickness of Ordovician limestone top utilization and grouting transformation. The directional drilling exploration was carried out by drilling from the two opposite ends of …
Optimization Design Of High Loess Slope Based On Combination Of Wide And Narrow Platform：A Case Study Of An Industrial Square In Zichang City,
2022
School of Geology Engineering and Geomatics, Chang’an University, Xi’an 710054, China
Optimization Design Of High Loess Slope Based On Combination Of Wide And Narrow Platform：A Case Study Of An Industrial Square In Zichang City, Nan Ning, Li Peng, Su Shengrui, Dong Fu, Ma Chi
Coal Geology & Exploration
The construction of a coal mine industrial square in a mountainous area or hilly area will face the problem of high slopes. The unreasonable high slope design causes serious waste of land resources, environmental damage and an increase in investment, and also brings huge potential safety risks to the infrastructure. Based on this, with a high slope in a coal mine industrial square in Zichang City of Shaanxi Province as an example, the field investigation, theoretical analysis and numerical simulation were used to investigate the influence of different numbers, positions and widths of wide platforms on the stress, strain field …
Conical Source Transient Electromagnetic Response Characteristics With Overburden Based On Occam Constrained Inversion,
2022
School of Geophysics and Measurement and Control Technology, East China University of Technology, Nanchang 330013, China
Conical Source Transient Electromagnetic Response Characteristics With Overburden Based On Occam Constrained Inversion, Li Zhe, Yang Haiyan, Yue Jianhua, Liu Zhixin, Jiang Zhihai, Su Benyu, Zhang Hua, Wang Ling, Yang Fujie
Coal Geology & Exploration
The overburden thickness and conductivity can affect transient electromagnetic response in shallow subsurface investigation. In order to further verify the overburden detection effect with a conical source device, combining all-time apparent resistivity conversion of transient electromagnetic field, the electromagnetic response characteristics of the underlying strata influenced by the overburden was studied by introducing an Occam inversion with stratum information constraints. The results indicate that electromagnetic response intensity of the target layer is related to the resistivity ratio of the overburden to the target layer. With the overburden resistivity gradually increasing, the resistivity fitting degree between inversed data and real value …
Influence Of Admixtures On The Performance Of Soundless Chemical Demolition Agents And Implications For Their Utilization,
2022
Carleton College, Department of Geology, Northfield, Minnesota, 55057, USA
Influence Of Admixtures On The Performance Of Soundless Chemical Demolition Agents And Implications For Their Utilization, Nattamon Maneenoi, Raphael Bissen, Sakonvan Chawchai
Journal of Sustainable Mining
Soundless Chemical Demolition Agents (SCDAs) are an environmentally friendly and safer alternative to traditional rock fragmentation methods. Admixtures are used to change the rheological properties and performance of SCDAs. This study aimed to investigate the effect of various concentrations of chemical accelerators (chloride salts) and viscosity enhancing agents (VEAs: Xanthan gum, Guar gum, and Gellan gum) on the fracture onset compared to an unmodified SCDA (BRISTAR 100®). All experiments were conducted on Portland Type 1 (OPC 1) cement blocks. The flowability of the mixtures was determined by mini-slump tests. Results show that 4wt% MgCl2 and 3wt% CaCl2 have accelerated the …
4d Gas Geological Research On Coal Seam With Gas Hazard Potential In Mining Panel,
2022
Henan Polytechnic University (HPU), School of Safety Science and Engineering, China
4d Gas Geological Research On Coal Seam With Gas Hazard Potential In Mining Panel, Hongqing Cui, Xin He, Zehua Wang
Journal of Sustainable Mining
According to regulations of the mining industry in China, it is necessary to carry out gas hazard prevention projects in advance when mining coal seams with gas hazard potential, and gas geological research should be taken as the basic work for optimal design and effective construction of gas hazard prevention projects. Research on coal seam with gas hazard potential have shown that anomalous geological area could be the gas hazard potential area as well, where superimposed tectonic and mining stress field usually results in tectonically disturbed coal and pressured gas. A 4D gas geological research method is used to find …
The Tertiary Sequence Of Varkala Coastal Cliffs, Southwestern India: An Ideal Site For Global Geopark,
2022
Michigan Technological University
The Tertiary Sequence Of Varkala Coastal Cliffs, Southwestern India: An Ideal Site For Global Geopark, K. S. Sajinkumar, M. Santosh, V. R. Rani, Subhash Anand, A. P. Pradeepkumar, Anil Chavan, K. P. Thrivikramji, P. V. Ramachandran
Michigan Tech Publications, Part 1
Varkala, along the southwestern coast of Peninsular India, has a unique place in Indian geology and geomorphology due to the presence of coastal lateritic cliffs, which exposes the entire Mio-Pliocene sequence of Warkalli Formation, and is declared as the type area. Stratigraphically, this formation exposes carbonaceous clay with lenses of lignite and sticks of marcasite, followed by variegated clays and sandstone. The presence of variegated lithounits endows beauty to these cliffs. Varkala cliffs, edging the Arabian Sea, run for a length of 7.5 km. These cliffs, together with confined beaches, made Varkala a popular tourist destination. Several geodiversity spots within …
Application Of Leeb Hardness Test In Prediction Of Dynamic Elastic Constants Of Sedimentary And Igneous Rocks,
2022
Missouri University of Science and Technology
Application Of Leeb Hardness Test In Prediction Of Dynamic Elastic Constants Of Sedimentary And Igneous Rocks, Sasan Ghorbani, Seyed Hadi Hoseinie, Ebrahim Ghasemi, Taghi Sherizadeh
Mining Engineering Faculty Research & Creative Works
The Leeb hardness test is a non-destructive and portable technique that can be used both in the laboratory and in-field applications. The main purpose of this study is to predict the dynamic elastic constants of the igneous and sedimentary rocks using Leeb dynamic hardness testing. For this purpose, three vital topics have been investigated and analyzed. First, the relationships between ultrasonic wave velocities and dynamic elastic constants with the Leeb hardness were investigated. Thereafter, by determining the rock quality index (IQ) using microscopic studies and by analyzing the quality index-porosity plot, the variation of the Leeb hardness values was studied. …
Performance Analyses Of Conventional Hot Mix Asphalt With Waste Additives,
2022
Missouri University of Science and Technology
Performance Analyses Of Conventional Hot Mix Asphalt With Waste Additives, Muhammad Naveed, Muhammad Azeem Raza, Raza Mehmood
Mining Engineering Faculty Research & Creative Works
The continuous increase in traffic volume demands performance enhancement of pavements. Common techniques for this performance improvement utilize modifications in the conventional hot mixture asphalt (HMA) through additives. Utilization of urban waste materials as additives for HMA provides opportunity for effective utilization and disposal of these unwanted materials. In this research, two waste materials, low-density polyethylene (LDPE) and crumb rubber (CR), are tested as additives to HMA for performance enhancement, optimization, and cost effectiveness. Performance evaluations are made through comparing stiffness modulus. Stiffness moduli of conventional and waste-material-modified HMA mixtures are evaluated through creep testing. Further, the effect of asphalt …
Geological Structure Detection With Tunnel Transient Electromagnetic Kirchhoff 2d Migration Imaging,
2022
School of Geology Engineering and Geomatics, Chang’an University, Xi’an 710054, China
Geological Structure Detection With Tunnel Transient Electromagnetic Kirchhoff 2d Migration Imaging, Qi Zhipeng, Guo Jianlei, Sun Naiquan, Li Xiu, Fan Yanan
Coal Geology & Exploration
The green construction of tunnel requires not only predicting disaster anomalies such as water inrush and mud inrush in front of tunnel face, but also identifying geological structure to support disaster warning and prevention. The traditional transient electromagnetic interpretation method can only provide resistivity information, which not meet the requirements of tunnel geological disaster management. Therefore, virtual wavefield imaging technology is introduced into the tunnel detection to achieve comprehensive interpretation of the electrical information and structures of disaster anomalies. Firstly, transient electromagnetic data is transformed into virtual wave field. Then, the resistivity imaging method was used to calculate the resistivity …
A Review：Geological Feasibility And Technological Applicability Of Underground Coal Gasification,
2022
Ministry of Education Key Laboratory of Coalbed Methane Resources and Accumulation Process, China; University of Mining and Technology, Xuzhou 221116, China College of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China
A Review：Geological Feasibility And Technological Applicability Of Underground Coal Gasification, Jiang Xiuming, Wu Caifang
Coal Geology & Exploration
Underground coal gasification (UCG) is a potential new method of coal utilization, which is of great significance for alleviating China’s energy crisis, ensuring national energy security, and achieving carbon peaking and carbon neutrality goals. It has always been valued by countries all over the world. On the suitability of UCG resource conditions, the feasibility of process and technology, and the controllability of environmental impact, this paper summarizes the development status of UCG technology, and clarifies the coal resource reserves suitable for UCG technology, different standards of geological area selection and location selection technology, the development history and applicable conditions of …
Simplified Internal Variable Gradient Model For Zonal Disintegration Of Rocks In Circular Underground Tunnels,
2022
Institute of Architectural Engineering, Huanghuai University, Zhumadian 463000, China
Simplified Internal Variable Gradient Model For Zonal Disintegration Of Rocks In Circular Underground Tunnels, He Ziguang, Zhao Fasuo, Chen Haoxiang, Wu Bo, Zhou Jingjing
Coal Geology & Exploration
As one of the typical nonlinear phenomena of deep level surrounding rock masses, zonal disintegration has captured many attentions of geotechnical engineers in the past years. On the basis of the internal variable theory, the closed-form analytical solutions to stress, strain and displacement fields near circular tunnels are obtained. The gradient-dependent solutions are compared with the results of the classical elasticity theory, and the effects of microstructures on the stresses and deformation fields are investigated as well. It is noted that the stress and deformation fields derived from the gradient model show remarkable quasi-periodicity and fluctuation, which is consistent with …
Powder Discharge Characteristics Of Pneumatic Double Pipe Directional Drilling In Broken Soft Coal Seams And Its Application,
2022
China Coal Research Institute, Beijing 100013, China
Powder Discharge Characteristics Of Pneumatic Double Pipe Directional Drilling In Broken Soft Coal Seams And Its Application, Nie Chao, Wang Yi, Yao Yafeng, Hong Jianjun
Coal Geology & Exploration
To study the influence of casing, casing bit size and casing rotational speed on pulverized coal discharge in double pipe directional drilling technology, three kinds of casing and casing bits in different sizes are designed respectively against the background of pneumatic double pipe directional drilling in the broken soft coal seam, the changes of the discharge rate and outlet velocity of pulverized coal under different combinations are analyzed, and the influence law of different casing rotational speeds on the suspension rate and conveying trajectory of pulverized coal are obtained. The numerical simulation results show that the ø120/96 mm casing with …
