Analysis Of Bit Balling And Application Of The Balling-Preventing Drilling Fluid In Well Songke-2,
2020
School of Engineering, China University of Geosciences(Wuhan), Wuhan 430074, China
Analysis Of Bit Balling And Application Of The Balling-Preventing Drilling Fluid In Well Songke-2, Hu Yule, Hu Chen, Zhang Hengchun, Zheng Wenlong
Coal Geology & Exploration
In order to solve the problem of the high mud content and easy hydration and dispersion of the Cretaceous sedimentary strata in well Songke-2, the bit balling is prone to occur in the water-based drilling fluid environment, which affects the drill bit ROP and induces downhole adhesion stuck, the paper combined the core drilling technology of well Songke-2, systematically analyzed of the causes of bit balling generated by the drill bit in the mudstone and water-based drilling fluid environment, provided a basis for the design of the anti-balling of the drill bit and the formulation of the anti-ball in drilling …
Table Of Contents,
2020
China Coal Technology and Engineering Group (CCTEG)
Evaluation And Analysis Of Paleoenvironments Of The Neogene Oil Shale Of Zhangcun Formation, Qinshui Basin,
2020
Shanxi Branch of China National Geological Exploration Center of Building Materials Industry, TaiYuan 030031, China; College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024, China
Evaluation And Analysis Of Paleoenvironments Of The Neogene Oil Shale Of Zhangcun Formation, Qinshui Basin, Liu Yanhai, Li Kunjie, Liu Dongna, Xue Shubin, Liu Yangfe, Chu Yonghui
Coal Geology & Exploration
In order to deeply analyze the indication of oil shale development characteristics on paleoenvironments and provide theoretical guidance for oil shale resource evaluation, the organic geochemistry and elemental geochemistry characteristics of the Neogene Zhangcun Formation oil shale in the central part of the Qinshui basin were analyzed by Rock-Eval and TOC and the paleoclimate and paleogeographic environments of the depositional period were discussed as well. The results show that the oil shale of Zhangcun Formation has the low oil content which Tar=4.15%, higher hydrocarbon potential, kerogen is of sapropel type(I1), which has relatively shallow burial depth. The element …
H2S Occurrence Conditions And Genetic Types Of Low Rank Bituminous Coal In Binchang Mining Area,
2020
Bin County Coal Co. Ltd., Xianyang 712000, China
H2S Occurrence Conditions And Genetic Types Of Low Rank Bituminous Coal In Binchang Mining Area, Liu Huibin, He Wanying, Jiang Bo
Coal Geology & Exploration
Based on the analysis of geological characteristics of the study area, it is considered that the geological conditions of H2S occurrence are the capping effect of dense surrounding rock on the roof and floor, the water-conducting fractured zone is unable to guide the overlying aquifer, and the low degree of coal metamorphism is not conducive to H2S adsorption, resulting in maximum H2S concentration of about 0.001 4% in the main mined coal seam 4 during the construction of Yadian mine at the north of Binchang mining area. Through the analysis of sulfur distribution, sulfate …
Pyrolysis Characteristics And Pyrolysis Product Composition Of Bituminous Coal Under Weak Oxidizing Atmosphere,
2020
Inner Mongolia Huang Tao Le Ge Coal Co. Ltd., Shandong Energy Zibo Mining Group Co. Ltd., Ordos 017313, China
Pyrolysis Characteristics And Pyrolysis Product Composition Of Bituminous Coal Under Weak Oxidizing Atmosphere, Zang Libin, Cui Hufeng, Li Qingchun
Coal Geology & Exploration
In order to improve the light tar and gas yield, the yield distribution and composition characteristics of pyrolysis products of bituminous coal from Shaanxi Hongliulin in the nitrogen atmosphere and weak oxygen atmosphere were studied in a fixed bed reactor. The results showed that the yield of char and tar were reduced under the weak oxygen atmosphere, and the yield of CO and CO2 increased significantly, leading to the increase of total gas yield. Due to the oxidation combustion reaction, the yield of H2, CH4 and C2-C3 gradually decreased with the increase of …
Aggregation And Sedimentation Experiments Of Coal Fines With Different Particle Sizes During Cbm Development,
2020
College of Geoscience & Surveying Engineering, China University of Mining & Technology(Beijing), Beijing 100083, China
Aggregation And Sedimentation Experiments Of Coal Fines With Different Particle Sizes During Cbm Development, Wei Yingchun, Cui Maolin, Zhang Jin, Meng Tao, Yao Zheng
Coal Geology & Exploration
During the development process of coalbed methane, the aggregation and sedimentation of coal fines can block the migration channel of coalbed methane and lead to accidents such as stuck pump and buried pump. In order to find out the aggregation and sedimentation characteristics of coal fines with different particle sizes, the aggregation and sedimentation experiments of coal fines with the particle size>140 mesh(<106 μm), 70 to 140 mesh(106-212 μm) and 50 to 70 mesh(212-300 μm) in deionized water were carried out. The aggregation and sedimentation characteristics of coal fines with different particle sizes in deionized water suspension were investigated from the suspension observation, the concentration characteristics of coal fines and the particle size distribution of coal fines in suspension. The results show that with the increase of the time, the color of coal fines suspension becomes lighter to different degrees, and the stratification of coal fines suspension gradually appears, and the suspension of coal fines with the particle size more than 140 mesh was the first to stratify among three suspensions. The smaller the particle sizes of coal fines, the more coal fines float on the top of the suspension, and the larger the particle sizes of coal fines, the more coal fines sink to the bottom of the suspension. The concentration of coal fines in the suspensions decreased to different degrees with the increase of the time. The concentration of coal fines decreased the fastest within 3 minutes after stopping the stirring. The concentration of coal fines with the particle sizes of 70 to 140 mesh in suspension was the largest among three suspensions. According to the particle size distribution curves, the process of aggregation and sedimentation of coal fines was divided into three stages: single peak to double peak(rapid floating and settlement of coal fines), double peak to single peak(rapid accumulation and settlement of coal fines) and single peak(slow sedimentation of coal fines). Coal fines with particle size more than 140 mesh in the suspension was the first to reach the stage of slow sedimentation, and coal fines with particle size of 70-140 mesh in the suspension reached the stage of slow sedimentation at the latest among three suspensions. The mechanism of aggregation and sedimentation of coal fines was discussed from the aspects of the force of coal fines, the extended DLVO theory, and the organic molecular structure of coal fines. The coal samples contain a large number of hydrophobic groups, such as aliphatic hydrocarbon and aromatic hydrocarbon, therefore, they have strong hydrophobicity and low wettability. With the decrease of particle sizes of coal fines, its specific surface area increases significantly, and a large amount of air is absorbed on the surface of coal fines, forming an air film. At the same time, particles of coal fines are adsorbed and aggregated with each other, and many micro pores are formed inside, resulting in that coal fines with small particle size is easy to aggregate and float on the suspension surface.
Progressive Gas Extraction Technology In Broken Soft Coal Seam Of Qinglong Coal Mine, Guizhou Province,
2020
Qinglong Coal Mine, Guizhou Qianxi Energy Development Company Limited, Bijie 551700, China
Progressive Gas Extraction Technology In Broken Soft Coal Seam Of Qinglong Coal Mine, Guizhou Province, Liang Daofu, Cao Jianming, Dai Mao, Chu Zhiwei, Zhang Lei
Coal Geology & Exploration
Aiming at the problems of uncontrollable trajectory, shallow borehole depth and poor gas extraction effect in gas treatment drilling of broken soft coal seam in Qinglong coal mine, the regional progressive gas extraction technology in broken soft coal seam based on compressed-air directional drilling was proposed, on the basis of analyzing the technical bottleneck of existing gas extraction borehole with rotary drilling. The principle and advantage of the technology was expounded, the technology of directional drilling by compressed-air, the technology of long distance in-seam drilling, and the technology of compound slag discharge by double power were integrated. The field test …
Geological Modeling-Based Productivity Response Characteristics Of The Cbm Well In Baode Unitⅰ,
2020
School of Energy Resource, China University of Geosciences(Beijing), Beijing 100083, China; Coal Reservoir Laboratory of National Engineering Research Center of CBM Development & Utilization, China University of Geosciences(Beijing), Beijing 100083, China
Geological Modeling-Based Productivity Response Characteristics Of The Cbm Well In Baode Unitⅰ, Chen Bo, Tang Dazhen, Lin Wenji, Li Song, Zhong Guanghao, Zhu Xueguang
Coal Geology & Exploration
Coalbed methane resource conditions and reservoir physical conditions are the basis of CBM exploration and exploitation. The geological modeling of CBM reservoir was carried out to clarify the spatial distribution of coal reservoir, and explain the difference of single well productivity, which can provide theoretical basis for selection and well drilling. This paper took Baode unit I as research object. Based on the measured data of gas content and well test permeability, the inversion model of gas content and permeability in the study area was established by using support vector machine algorithm(SVM) and transformed F-S permeability calculation formula, and the …
Quantitative Evaluation Of The Contamination Degree Of The Drilling Fluid For Fractures Of Different Scale In Coal,
2020
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454003, China
Quantitative Evaluation Of The Contamination Degree Of The Drilling Fluid For Fractures Of Different Scale In Coal, Zhang Jingshuo, Ni Xiaoming, Li Yang, Li Zongyuan, Cao Yunxing
Coal Geology & Exploration
During coalbed methane well drilling, the drilling fluid contaminates and blocks the pores and fractures of coal seam. In order to find out the difference of pollution degree of drilling fluid coal and the contribution rate of the pores and fractures of different scale to permeability, the coal of Changping mine was taken as the research object, the scanning electron microscopy(SEM) and the Image Pro Plus(IPP) processing technology were used, the parameters such as the average length, the average width, the total area and the total perimeter of the fractures of different scales in coal before and after contamination were …
Discussion On The Three-Dimensional Development Model Of The Old Well Pattern In Coalbed Methane Field,
2020
Huabei Oilfield Shanxi CBM Branch Company of Huabei Oilfield Company PetroChina, Changzhi 046000, China
Discussion On The Three-Dimensional Development Model Of The Old Well Pattern In Coalbed Methane Field, Li Jun, Zhang Cong, Zhang Jianguo, Peng He, Cui Xinrui, Zhu Min
Coal Geology & Exploration
In order to increase the degree of production of CBM development blocks, when the production of a single well enters a decline period, the development plan needs to be adjusted, and the production increase and stability can be achieved through the measures such as layer adjustment or layer compensation. In terms of time, it is believed that the main coal seam should be developed first when it is put into production. After the decline period, the secondary main coal seam should be supplemented and combined; in space, combined with the development dynamics, the analytic hierarchy process is used to determine …
Hydrochemical Characteristics And Formation Mechanism Of Ordovician Limestone Water In Baode Coal Mine,
2020
China Coal Research Institute, Beijing 100013, China; Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710077, China
Hydrochemical Characteristics And Formation Mechanism Of Ordovician Limestone Water In Baode Coal Mine, Zhang Zeyuan, Xu Feng, Wang Shidong, Liu Qisheng
Coal Geology & Exploration
Ordovician limestone karst water is the main threatening water source for mining activities in Baode coal mine, and it is one of the main water supply sources. Ordovician limestone karst water samples were systematically collected in Baode coal mine, and the methods of correlation analysis, ion proportional coefficient, saturation index inversion simulation and Chlor-Alkali index were chosen to analyze the hydrochemical characteristics and its formation mechanism. The results showed that the water quality types of Ordovician limestone water changed from runoff zone to stagnant zone in a trend of HCO3-Na(Na·Ca)→HCO3·Cl-Na·Ca(Ca·Mg)→Cl-Na(Na·Ca). The mass concentration of each ion …
Development Characteristics Of Water-Conducting Fractured Zone In Deep Coal Seam Based On Microseismic Monitoring,
2020
College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China
Development Characteristics Of Water-Conducting Fractured Zone In Deep Coal Seam Based On Microseismic Monitoring, Hou Enke, Fan Jichao, Xie Xiaoshen, Long Tianwen, Zhang Huanlan, Wang Jianhui, Fan Zhigang
Coal Geology & Exploration
The development height of the water conducting fractured zone is one of the important technical parameters for mine water hazards prediction. In this paper, the combined well-surface microseismic monitoring technology was used to analyze the development characteristics of the water conducting fractured zone in working face 4103 in Wenjiapo coal mine. The results showed that for deep buried coal seams, the microseismic events occured in the advance mining face with advanced influence angle ranging from the minimum of 28° to the maximum of 35°. The stability of overburden decreased due to the faults. Thus, compared with normal bedrock, the overburden …
Damaged Constitutive Model Of Frozen Sand Under The Influence Of Intermediate Principal Stress,
2020
State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines, Anhui University of Science and Technology, Huainan 232001, China; School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232002, China
Damaged Constitutive Model Of Frozen Sand Under The Influence Of Intermediate Principal Stress, Ma Shilong, Yao Zhaoming, Liu Shuang, Pan Xuan
Coal Geology & Exploration
Artificial freezing is a commonly used method for stopping water and providing temporary support during the excavation of saturated sand. This study on the damage characteristics of frozen soil lays the foundation for the analysis of the mechanical properties of frozen soil and the stability of frozen bodies. In order to study the damage mechanical properties of frozen sand, three-dimensional laboratory tests on frozen sand with different intermediate principal stress coefficients were carried out at -5℃. Based on the Weibull random distribution of micro element failure of frozen soil, the Drucker-Prager strength criterion was invoked as the statistical distribution variable, …
Numerical Experiment On Damage And Fracture Of Shale Based On Micro-Scale,
2020
College of Civil Engineering, Guizhou University, Guiyang 550026, China
Numerical Experiment On Damage And Fracture Of Shale Based On Micro-Scale, Cui Hengtao, Wu Zhonghu, Lou Yili, Zuo Yujun, Sun Wenjibin, Liu Hao
Coal Geology & Exploration
Correctly understanding the micro-scale fracture characteristics of the Lower Cambrian shale and the evolution law of acoustic emission signals are of great reference value in the study of shale mechanical characteristics, fracture mechanism and shale gas development and utilization. In this paper, based on digital image processing technology, the non-uniform characterization of quartz-filled shale is carried out, and a numerical model is established using the real rock fracture analysis system RFPA2D-DIP to simulate the failure process of shale under different confining pressures. The test results show that under the micro-scale structure, the shale failure mode can be roughly …
Characteristics Of In-Situ Stress Field And Stability Analysis Of Roadway In Hongqingliang Coal Mine,
2020
College of Mining, Liaoning Technical University, Fuxin 123001, China
Characteristics Of In-Situ Stress Field And Stability Analysis Of Roadway In Hongqingliang Coal Mine, Rong Hai, Han Yongliang, Zhang Hongwei, Xin Jinxin, Cao Yu, Lan Tianwei
Coal Geology & Exploration
The in-situ stress of 3-1 coal seam in Hongqingliang coal mine was measured by hollow core inclusion measurement, and distribution characteristics of in-situ stress field were obtained in order to solve the problem of serious deformation in mining roadway. Fault structures of grade Ⅰ-Ⅴ in Hongqingliang coal mine were divided by geo-dynamic division method, and the stress areas were divided and the stability of roadways was analysis by rock stress state analysis system. The research showed that the in-situ stress field in Hongqingliang coal mine belongs to the horizontal tectonic stress field, which is dominated by horizontal compressive stress. The …
Model Of Surface Subsidence Basin For Long-Wall Working Face Along Strike Of Gently Inclined Coal Seam,
2020
College of Geology & Environment, Xi’an University of Science and Technology, Xi’an 710055, China
Model Of Surface Subsidence Basin For Long-Wall Working Face Along Strike Of Gently Inclined Coal Seam, Tang Yichuan, Xing Congcong, Liu Donghai, Deng Niandong, Yao Ting, Shang Hui
Coal Geology & Exploration
In order to accurately describe the distribution of surface subsidence basin, and based on the power exponential function model and the subsidence features, the surface subsidence basin model of long-wall working face along strike with gently inclined coal seam was established concerned the combination of theoretical analysis and numerical simulation method. The influencing factors of model parameters and the changing patterns of parameters were analyzed, and the applicability and the predicting accuracy of the model were verified. The results showed that parameter n reflected the range of the bottom size of the sinking basin, which was mainly related to the …
Effect Of Thermally Conductive Filler On Thermal Conductivity Of Cementing Materials In Geothermal Wells,
2020
China Coal Research Institute, Beijing 100013, China; Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710078, China
Effect Of Thermally Conductive Filler On Thermal Conductivity Of Cementing Materials In Geothermal Wells, Yang Yu, Xu Shuanhai, Zhang Hao, Han Yongliang, Zhang Weidong
Coal Geology & Exploration
Adding heat-conducting filler to the cement of the geothermal well could significantly improve the thermal conductivity of the cement stone and enhance the heat extraction effect of the geothermal well. In this study, on the basis of summarizing the heat conduction path theory and concept of high packing density, the effects of different filler types, particle sizes and dosages on the thermal conductivity of cementing cement were investigated through experiments. The test results showed that graphite had the best effect on improving the thermal conductivity of cement stone compared to other types of filler; the larger the graphite particle size, …
Multi Parameter Monitoring System And Device For Mine Gas Drainage,
2020
Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710077, China
Multi Parameter Monitoring System And Device For Mine Gas Drainage, Dai Chenyu
Coal Geology & Exploration
In order to make up for the deficiency of the regional monitoring of the traditional gas drainage monitoring system, this paper proposes to build a borehole gas drainage monitoring system with borehole as the monitoring unit, which can dynamically grasp the drainage effect of each borehole in the process of gas drainage in real time, change the large area regional measurement into the measurement of each borehole in the region, and realize the fine monitoring of gas drainage. According to the requirements of borehole gas drainage monitoring system, combined with the characteristics of gas drainage parameters at the borehole orifice, …
Application Of The Dip Curvature Attributes In The Recognition Of Coal Roadway,
2020
Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710078, China
Application Of The Dip Curvature Attributes In The Recognition Of Coal Roadway, Shan Rui
Coal Geology & Exploration
The intelligent accurate coal mining needs to construct the high-precision and transparent 3D geological model, and the seismic data interpretation integrated into the dynamic roadway data provide data support for the model. The geological model of roadway is established and forward modeling is carried out to analyze the difference of seismic characteristics caused by a roadway. Based on curvature attribute principle, various seismic curvature attributes were applied to seismic data interpretation, guide the roadway recognition in the seismic data. The coal seam 2 of CJT coalfield was selected as the research object, and the high-quality seismic data and various attribute …
Microseismic Vector Scanning-Based Natural Fracture Monitoring Of The Coalbed Methane Wells,
2020
COSL Oilfield Production Research Institute, Tianjin 300460, China
Microseismic Vector Scanning-Based Natural Fracture Monitoring Of The Coalbed Methane Wells, Liu Zixiong
Coal Geology & Exploration
The development degree of natural fractures is the main factor affecting coalbed methane productivity. In order to accurately obtain the distribution position of the natural fractures in the a coalbed methane field in the southern Qinshui basin, 7 refracturing wells in the area were adopted by surface microseismic vector scanning to monitor the natural fractures. A certain amount of three-component geophones were deployed around the fracturing well to collect microseismic events in the surrounding reservoir during fracturing, and after Semblance superposition, the fracture energy slices at different times in the monitoring area were obtained to explain the natural fractures in …
