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2019

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Articles 151 - 180 of 544

Full-Text Articles in Oil, Gas, and Energy

Design Of Variable Wall Thickness Geometry And Performance Mapping Of Scroll Expanders For Distributed Power Generation, Arun Kumar Narasimhan Jul 2019

Design Of Variable Wall Thickness Geometry And Performance Mapping Of Scroll Expanders For Distributed Power Generation, Arun Kumar Narasimhan

USF Tampa Graduate Theses and Dissertations

Low-temperature heat sources such as industrial waste heat, solar, and geothermal are more suitable for small-scale power generation rather than utility scale. In order to maximize the electricity generated from low-temperature heat sources, an efficient expansion device for small-scale power output is necessary. This research work has focused on evaluating the use of a scroll expander and improving its geometrical design for the power output range of 1-25 kWe.

The first part of the work focusses on modeling the performance of a scroll expander using two non-dimensionless parameters, namely, specific speed and specific diameter. Performance of a scroll …


Lithological Character And Sequence Stratigraphy Of The Ste. Genevieve Limestone In Western Kentucky, Zachary Dalton Creech Jul 2019

Lithological Character And Sequence Stratigraphy Of The Ste. Genevieve Limestone In Western Kentucky, Zachary Dalton Creech

Masters Theses & Specialist Projects

The Ste. Genevieve Limestone is a Mississippian-aged, carbonate-dominated stratigraphic unit that is a prominent hydrocarbon producer in the Illinois Basin, and is widely distributed in states such as Missouri, Kentucky, Indiana, and Illinois. There has been relatively limited study focused on characterizing the Ste. Genevieve Limestone in terms of lithofacies, stacking patterns, and sequence stratigraphic context via analysis of roadcut exposures of the unit in western Kentucky.

The focus of this study is to use lithologic data collected from roadcuts and draft these data into cross sections for presentation of detailed stratigraphic columns that are locally correlative. Seven roadcuts were …


Laboratory Studies Of Rich Gas Interactions With Bakken Crude Oil To Support Enhanced Oil Recovery, Steven B. Hawthorne, James A. Sorensen, David J. Miller, Charles D. Gorecki, John A. Harju, Gordon Pospisil Jul 2019

Laboratory Studies Of Rich Gas Interactions With Bakken Crude Oil To Support Enhanced Oil Recovery, Steven B. Hawthorne, James A. Sorensen, David J. Miller, Charles D. Gorecki, John A. Harju, Gordon Pospisil

EERC Publications, Papers, & Presentations

Lab studies are being conducted to determine the effect of different rich gases on their potential to enhance Bakken crude oil recovery. These include measuring the MMP of Bakken crude oil with different candidate gas injectants and measuring the hydrocarbon composition in the “miscible” phase generated by crude oil/injectant exposures.


Laboratory Investigation Of Co2 Injectivity And Adsorption Potential Within The Bakken Formation, Steven A. Smith, Bethany A. Kurz, James A. Sorensen, Christopher J. Beddoe, Blaise A.F. Mibeck, Alexander Azenkeng, Steven B. Hawthorne, Charles D. Gorecki Jul 2019

Laboratory Investigation Of Co2 Injectivity And Adsorption Potential Within The Bakken Formation, Steven A. Smith, Bethany A. Kurz, James A. Sorensen, Christopher J. Beddoe, Blaise A.F. Mibeck, Alexander Azenkeng, Steven B. Hawthorne, Charles D. Gorecki

EERC Publications, Papers, & Presentations

To assess CO2 injectivity and storage potential within the organic-rich shales and middle member of the Bakken Formation, a series of laboratory tests were performed.


Unconventional Rock Requires Unconventional Analysis: Methods For Characterization, Shane K. Butler, Alexander Azenkeng, Blaise A.F. Mibeck, Bethany A. Kurz, Kurt E. Eylands Jul 2019

Unconventional Rock Requires Unconventional Analysis: Methods For Characterization, Shane K. Butler, Alexander Azenkeng, Blaise A.F. Mibeck, Bethany A. Kurz, Kurt E. Eylands

EERC Publications, Papers, & Presentations

Advanced image analysis techniques were applied to better understand and quantify factors that could affect CO2 storage in the Bakken Formation, with an ultimate goal of improved method development to estimate CO2 storage potential of unconventional reservoirs.


Reasonable Length Of Working Face 11-101 During Mining Above Confined Aquifer In Tuanbai Mine, Li Gang, Zhang Kai, Su Junhui, Wang Jinbo Jun 2019

Reasonable Length Of Working Face 11-101 During Mining Above Confined Aquifer In Tuanbai Mine, Li Gang, Zhang Kai, Su Junhui, Wang Jinbo

Coal Geology & Exploration

The working face 11-101 of Tuanbai coal mine in Huozhou, Shanxi Province is exploited above aquifer. In order to prevent floor water inrush accidents during mining, research combination of elasto-plastic theory, on-site measurement and numerical simulation was carried out to analyze the development rule of failure depth of the floor, then the reasonable length of the mining face under this condition was determined. The result shows that with the advancement of working face, the bottom plate of lagging working face is stretched and destroyed at about 6 m behind the lagging working face, and the bottom plate has a wedge …


Table Of Contents, The Editors Jun 2019

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Development Of Data Acquisition And Control Software For Seismic Monitoring With Mining, Duan Jianhua, Wang Yunhong, Wang Baoli Jun 2019

Development Of Data Acquisition And Control Software For Seismic Monitoring With Mining, Duan Jianhua, Wang Yunhong, Wang Baoli

Coal Geology & Exploration

Seismic monitoring with mining can continuously detect and real-time predict geological anomalies in front of work, it has become a research hotspot in recent years, but at present, there is no equipment that can carry out seismic monitoring with mining in coal mine.Therefore, the development of seismic monitoring equipment with mining has become a top priority. In order to solve this problem, based on the MFC development framework, a set of seismic monitoring data acquisition software is developed. A three-month joint survey was carried out indoors and outdoors, and a three-month comprehensive trial operation was carried out in Yanjiao Coal …


Productivity Prediction Of Hypotonic Cbm Test Well In Jiaozuo Mining Area Under Hydraulic Fracturing, Wang Zhirong, Yang Jie, Chen Lingxia, Guo Zhiwei Jun 2019

Productivity Prediction Of Hypotonic Cbm Test Well In Jiaozuo Mining Area Under Hydraulic Fracturing, Wang Zhirong, Yang Jie, Chen Lingxia, Guo Zhiwei

Coal Geology & Exploration

In order to explore the permeable mechanism and the output law after fracturing of CBM in the "three soft" coal seam(soft coal, soft roof and soft bottom) of Jiaozuo under hydraulic fracturing, Based on the permeable model of reservoir fracture, considering the influence of fracture porosity on permeability after fracturing, a reservoir fracture penetration model was established, the application and analysis of the test well was carried out to obtain the characteristics of pressure cracks such as length, width, permeability and reservoir parameters after fracturing. Through the comprehensive analysis of isothermal adsorption curves and historical fitting, the recovery rate of …


Experiment On Methane Displacement In Coalbed By Supercritical Carbon Dioxide, Wu Di, Liu Xueying, Sun Keming, Xin Liwei, Miao Feng Jun 2019

Experiment On Methane Displacement In Coalbed By Supercritical Carbon Dioxide, Wu Di, Liu Xueying, Sun Keming, Xin Liwei, Miao Feng

Coal Geology & Exploration

Using self-made experimental system, experiments were performed on coal samples to study supercritical CO2 seepage, adsorption and CH4 displacement by supercritical CO2. Experimental results show that permeability and adsorption of supercritical CO2 in coal increase with CO2 pressures. Pressures and temperatures of CO2 influence the values of displaced CH4. Values of displaced CH4 increase by average 0.076 cm3/g and sweep efficiency rises by 17%-23% with the CO2 pressure increasing from 8 MPa to 12 MPa, while displacement volume decreases linearly. With the temperature rising by 10℃, sweep …


Genesis And Geochemical Characteristics Of Coalbed Methane From Taiyuan Formation In Sijiazhuang Mine Field Of Yangquan Mining Area, Yu Zhenfeng, Hao Chunsheng, Yang Changyong, Yao Jinbao, Wang Wei, Ji Changjiang Jun 2019

Genesis And Geochemical Characteristics Of Coalbed Methane From Taiyuan Formation In Sijiazhuang Mine Field Of Yangquan Mining Area, Yu Zhenfeng, Hao Chunsheng, Yang Changyong, Yao Jinbao, Wang Wei, Ji Changjiang

Coal Geology & Exploration

In order to study the geochemical characteristics and the genesis of CBM of Sijiazhuang mine field in Yangquan mining area, the in-site desorption test of coal core samples from the main gas-producing seams(seams 8, 9 and 15) from Permo-Carboniferous Taiyuan Formation was carried out systematically, gas samples were collected to conduct component and carbon isotope analysis. The results indicated that the gas content of seam 8 was higher than that of seam 9, on the plan the gas content of seam 15 was uneven, in some parts there was almost no gas. During the whole desorption, the gas component content …


Formation Mechanism Of Coal Seam Aquifer And Water Hazard Control Technology, Wang Hao Jun 2019

Formation Mechanism Of Coal Seam Aquifer And Water Hazard Control Technology, Wang Hao

Coal Geology & Exploration

Coal seams occur in Peat formation formed by sediments, often used as aquiclude or aquitard in coal production. However, in Barapukuria coal mine in Bangladesh, No.VI coal seam is rich in water, shows a typical hydrogeological phenomenon that the coal seam becomes an aquifer, which is rare in coal mining process both in China and abroad. From the formation mechanism of coal and the microstructure and tectonic development characteristics of coal, the structure of rich in water of coal was revealed. Based on MTS815 rock mechanics test system, the permeability of No.VI coal was tested, and the internal structure of …


Comparison Of Dissolution Characteristics Of Organic Matter In Coal Gangue Of Different Geological Time, Sun Yanfang, Zhao Li, Luo Shaohe, Zhang Lei, Sun Chao, Li Bowen Jun 2019

Comparison Of Dissolution Characteristics Of Organic Matter In Coal Gangue Of Different Geological Time, Sun Yanfang, Zhao Li, Luo Shaohe, Zhang Lei, Sun Chao, Li Bowen

Coal Geology & Exploration

Taken the unweathered coal gangues obtained from the Jurassic coalbed of Bulianta mine and the Car-boniferous-Permian coalbed of Baode mine located in Shendong mining area as the research subjects, the dissolution characteristics of organic matter in two kinds of coal gangues were studied comparatively through soaking experiments, and combined with three-dimensional fluorescence spectrometry and parallel factor analysis. It is significant for the underground reservoir to study mechanism of water treatment in coal mining areas. These results indicate that the total ion concentration in DOM sample of coal gangue of Bulianta mine is higher than that of Baode mine due to …


Effect Of Clay Content On Shear Strength Of Loess, Wang Li, Li Xi'an, Hong Bo, Du Shaoshao, Zhang Hangbo, Zhao Ning Jun 2019

Effect Of Clay Content On Shear Strength Of Loess, Wang Li, Li Xi'an, Hong Bo, Du Shaoshao, Zhang Hangbo, Zhao Ning

Coal Geology & Exploration

The experimental research about effect of different clay content on shear strength of loess was carried out to reveal the influence of clay content on shear strength and its microscopic mechanism, and then a scientific basis for engineering practice of loess was provided. Self-made wet sieve device under negative pressure was applied to screen loess samples with different clay content. Different clay content of the loess samples were made to the same dry density, but with different moisture content using static pressure method, and then were taken direct shear test. The results show that with the increase of moisture content, …


Experimental Study On The Influence Of Well Inclination Angle Of Coalbed Methane Well On The Cementation Strength Of Cement-Formation Interface, Gu Jun, Li Linwei, Sun Dexing Jun 2019

Experimental Study On The Influence Of Well Inclination Angle Of Coalbed Methane Well On The Cementation Strength Of Cement-Formation Interface, Gu Jun, Li Linwei, Sun Dexing

Coal Geology & Exploration

In order to control the problem of water channeling in the process of coalbed methane(CBM) production, based on the self-designed test device and method, the test data of the shear strength at cement-aquiclude interface (CAI) is obtained under the conditions of well inclination of 0°, 30°, 60° and 90°. The mechanism of the influence of inclination angle on the shear strength at CAI is analyzed. The results show that the shear strength at CAI decreases with the increase of the inclination angle. The reason is that as the inclination angle increases, the upper part of the mud cake ring becomes …


The Matching Of Gas Production Curve Characteristic And Reservoir Conditions In Vertical Coalbed Methane Wells, Han Wenlong, Wang Yanbin, Liu Du, Chang Hong, Ding Tao Jun 2019

The Matching Of Gas Production Curve Characteristic And Reservoir Conditions In Vertical Coalbed Methane Wells, Han Wenlong, Wang Yanbin, Liu Du, Chang Hong, Ding Tao

Coal Geology & Exploration

The matching of coalbed methane(CBM) production curve type and geological conditions directly affects the gas production. Based on dividing gas production curves types of vertical CBM wells in the southern block of Shizhuang in Qinshui basin over 4 years, the characteristics of gas production curve were analyzed. The matching of gas production curve with reservoir parameters was further analyzed. The paper discovered and divided the gas production curve into four types:type of fast rising of single peak, type of stable rising of single peak, bimodal type of being low later and bimodal type of being high later. The original permeability, …


The Seepage Characteristics Of A Single Well Dewatering From An Unconfined Aquifer Bottom, Li Yang, Wang Wenxue, Xiao Hang, Sun Yi, Wang Yun, Di Mengna Jun 2019

The Seepage Characteristics Of A Single Well Dewatering From An Unconfined Aquifer Bottom, Li Yang, Wang Wenxue, Xiao Hang, Sun Yi, Wang Yun, Di Mengna

Coal Geology & Exploration

Dewatering from an aquifer bottom for drain and depressurization is one common method to ensure safety mining. This method is significantly different from pumping from the ground. In order to study the seepage characteristics of the dewatering hole(well), the seepage characteristics of a single well dewatering from an unconfined aquifer bottom was taken as an example and studied using numerical simulation method. The results show that when lw<lc, the pore water pressure above the dewatering well is greater than zero, which presents the rule of increasing first then decreasing from bottom to top, and the seepage …


The Development Of Seismic-While-Mining Detection Technology In Underground Coal Mines, Cheng Jianyuan, Qin Si, Lu Bin, Wang Baoli, Wang Ji Jun 2019

The Development Of Seismic-While-Mining Detection Technology In Underground Coal Mines, Cheng Jianyuan, Qin Si, Lu Bin, Wang Baoli, Wang Ji

Coal Geology & Exploration

The explosive source of underground seismic exploration in coal mines is greatly affected by the control of pyrotechnics and cannot realize the monitoring and early warning of dynamic geological disasters in coal mining. Seismic-while-mining(SWM) is a new technique based on shearer as a seismic source underground. The paper reviewed the research status of SWM technique at home and abroad, introduced the SWM's principle and its unique advantages. According to some pilot experiments of SWM, the results show that the shearer can be used as a seismic source because it has the character of strong excitation energy, wide frequency band, safety, …


Method Of Transparent Working Face Based On Dynamic Detection Of Cross Hole Seismic Subdivision, Lu Bin Jun 2019

Method Of Transparent Working Face Based On Dynamic Detection Of Cross Hole Seismic Subdivision, Lu Bin

Coal Geology & Exploration

Transparent working surface is an important part of intelligent coal mining. It provides detailed geological structure information of working face for intelligent coal mining. This paper proposes a working surface exploration method based on segmented and dynamic cross-hole seismic, which can realize progressive fine detection of coal working face. The method is a new development with seismic while mining, which is using the coal cutter as seismic source. The main idea is to image the working face segmented by deploying some detectors in a series of horizontal holes parallel to the long wall. The method performs fine imaging on the …


Simulation Of Seismic-While-Mining With Shearer As Source Of Fully Mechanized Mining Face, Jin Dan Jun 2019

Simulation Of Seismic-While-Mining With Shearer As Source Of Fully Mechanized Mining Face, Jin Dan

Coal Geology & Exploration

In order to analyze the wave field characteristics of seismic-while-mining data excited by coal cutter as seismic source, forward simulation was used to calculate seismic data. We transform the cutting mode of spiral drum and the stress of drum into the force function of seismic source, which is added to the wave equation in the form of load distribution at different time and location. Wave equation is solved by high-order staggered-style finite difference method. Finally, the seismic data obtained by numerical simulation show that shear wave energy is very strong and press wave energy is very weak in the wave …


Quantitative Quality Evaluation Of Seismic-While-Mining Data, Qin Si, Cui Weixiong, Wang Wei Jun 2019

Quantitative Quality Evaluation Of Seismic-While-Mining Data, Qin Si, Cui Weixiong, Wang Wei

Coal Geology & Exploration

A seismic-while-mining(SWM) monitoring system laid in a working face of an underground coalmine will continuously generate tremendous amount of SWM data. When a coalmine cutting machine cuts coal seam actively, the SWM data will be of high correlation, and when it is not, the SWM data will be of low correlation or even no correlation at all. Based on this characteristic, a method for automatically and quantitatively evaluating the quality of SWM data was proposed. Using this method to process SWM data from a coal mine in Inner Mongolia, the result showed that this method can recognize the correlation peak …


Study On Noise Attenuation Of Seismic While Mining, Liu Qiang Jun 2019

Study On Noise Attenuation Of Seismic While Mining, Liu Qiang

Coal Geology & Exploration

In view of the closure of the environments and the high requirements of safe production of underground coal mine, the explosive source has many limitations in the operation of seismic exploration of coal mine, and the coal shearer as the source can avoid many inherent shortcomings of the source of explosives, has the advantage of real-time detection of the internal structure and the stress of the working face without affecting the normal operation of the mining face. However, as the energy generated by the shearer is much smaller than that of the explosive source, the quality of the collected signal …


Development And Application Of Software In Seismic While Mining Data Processing, Wang Baoli Jun 2019

Development And Application Of Software In Seismic While Mining Data Processing, Wang Baoli

Coal Geology & Exploration

The seismic while mining detection technology with coal cutter as seismic source in coal face is the key to accurately know the geological conditions of mining, improve the detection accuracy of geological anomaly structure in coal face, and realize unmanned intelligent mining or with few people. It has broad application prospects.The conventional seismic data processing software can not meet the requirements of real-time, continuous and large data volume for seismic while mining data. By analyzing the requirement of seismic while mining detection technology for data processing software(SWM), a framework of hierarchical and multi-task data processing software is proposed. The components …


Geological Evaluation Model For Site Selection Of Underground Coal Gasification Without Well In Jinghai Coal-Bearing Area, Tianjin, China, Wang Zhigang, Fu Xiaojin, Liang Jie, Cao Jian, Jiang Shengguo Jun 2019

Geological Evaluation Model For Site Selection Of Underground Coal Gasification Without Well In Jinghai Coal-Bearing Area, Tianjin, China, Wang Zhigang, Fu Xiaojin, Liang Jie, Cao Jian, Jiang Shengguo

Coal Geology & Exploration

Based on the 4 factors such as exploration status, coal seam, coal quality and hydrological conditions, using the secondary fuzzy comprehensive evaluation method, the geological evaluation model without well was built. In order to verify the applicability of the model, the material balance by law of conservation of mass was carried out and the results compared with the test results of indoor model was got. This research suggests that the weight of geological conditions affecting underground coal gasification without well is exploration status > conditions of coal seam > hydrological conditions > coal quality, the area with comprehensive score higher than 70 is …


Auxiliary Outburst Prevention Techniques By Surface Pre-Drainage For Coalbed Exposed In Tunnel And Mine Shaft, Zhang Dongliang Jun 2019

Auxiliary Outburst Prevention Techniques By Surface Pre-Drainage For Coalbed Exposed In Tunnel And Mine Shaft, Zhang Dongliang

Coal Geology & Exploration

How to expose an outburst-prone coal seam safely and efficiently in tunnel and mine shaft is always a subject to study continuously in outburst prevention, surface coalbed gas pre-drainage is an effective approaches for outburst prevention. Based on the analysis of outburst mechanism in tunnel and mine shaft and the core task of outburst prevention, the characteristics and adaptability of the outburst prevention techniques by surface pre-drainage are studied. Practical engineering application shows that the gas content and pressure in coal exposure area can be effectively reduced using surface pre-drainage well by cavern completion or hydraulic fracturing, the stress or …


Study On The Biodegradation Of Guanidine Gum By Methanogens In Coal Seam, Li Yunsong, Guo Hongyu, Fu Chaoyong, Zhao Guojun, Xia Daping Jun 2019

Study On The Biodegradation Of Guanidine Gum By Methanogens In Coal Seam, Li Yunsong, Guo Hongyu, Fu Chaoyong, Zhao Guojun, Xia Daping

Coal Geology & Exploration

The problem of low temperature breaking of guanidine gum fracturing fluid is related to the effect of coal seam penetration. In order to explore the effect of methanogenson the biodegradation of guanidine gum, Inner Mongolia some coal mine lignite were collected to prepare samples of coal samples, and the enriched fresh mine water was used as the bacteria source. The biological methane metabolism experiments of guanidine gum + coal were used to characterize the biodegradability of methanogens to guanidine gum, with the total gas production, CH4 concentration, guanidine gum molecular functional groups and C and H elements content changes. …


Study On Sediment Environment And Rock Mechanics Characteristics Of The Delta Plain Of Jurassic Coalfield In Northern Shaanxi, Wang Haijun, Ma Liang Jun 2019

Study On Sediment Environment And Rock Mechanics Characteristics Of The Delta Plain Of Jurassic Coalfield In Northern Shaanxi, Wang Haijun, Ma Liang

Coal Geology & Exploration

Delta plain sedimentary environment is one of the coal-forming environments of the coal resources of Jurassic coalfield in northern Shaanxi. In order to get the rock mechanics parameters and characteristics of coal seam roof in different environments and to further investigate the relationship between the sedimentary environments and the rock mechanics characteristics, firstly from the analysis of the regional sedimentary environments, then by using techniques such as accurate core description, sedimentary structural analysis, facies analysis of geophysical logging, the microfacies were recognized, the sedimentary microfacies types of roof and their combination characteristics were classified. Later, rock samples of different lithology …


Simulation And Test Of Enhancement Of Gas Drainage Through Co2 Injection Into Coal Seam Of Low Permeability, Bai Gang, Zhou Xihua, Wei Shiping, Fan Chaojun, Li Xueming Jun 2019

Simulation And Test Of Enhancement Of Gas Drainage Through Co2 Injection Into Coal Seam Of Low Permeability, Bai Gang, Zhou Xihua, Wei Shiping, Fan Chaojun, Li Xueming

Coal Geology & Exploration

In view of the difficulty of gas extraction and low drainage efficiency in coal seam of low permeability, based on multi component gas competitive adsorption of CO2-CH4, simulation and test for improving seam gas extraction rate through CO2 injecting CO2 into coal seam were carried out. A fluid-solid coupling model considering gas-water phases and Klinkenberg effect of CO2 injection into coal seam for enhancement of gas drainage was established, parameters of gas pressure, gas content and gas extraction rate after coal seam CO2 injection were analyzed by using COMSOL software and applied …


Application Of Sec Dynamic Reserves Evaluation Method In Coalbed Methane Field: A Case From Hancheng Block In Ordos Basin, Yi Wei, Xiong Xianyue, Cao Yimin, Ding Rong Jun 2019

Application Of Sec Dynamic Reserves Evaluation Method In Coalbed Methane Field: A Case From Hancheng Block In Ordos Basin, Yi Wei, Xiong Xianyue, Cao Yimin, Ding Rong

Coal Geology & Exploration

At present, all the SEC reserves evaluation of coalbed methane fields uses dynamic assessment methods. In the process of evaluation, the parameters and calculation results are various. In order to solve this problem, this paper takes the Hancheng block in Ordos basin as an example, a series of evaluation methods adapted to the production characteristics of coalbed methane have been comprehensively applied, optimizing various parameters, and summarizing the law of decline. The results show that geological units are divided according to tectonic conditions, and on this basis, evaluation units are divided according to development effect, which can objectively and reasonably …


Effects Of Pressure Drop Funnels Model Of Different Shapes On Cbm Well Productivity, Hu Haiyang, Jin Jun, Zhao Lingyun, Chen Jie, Gu Jiaoyang Jun 2019

Effects Of Pressure Drop Funnels Model Of Different Shapes On Cbm Well Productivity, Hu Haiyang, Jin Jun, Zhao Lingyun, Chen Jie, Gu Jiaoyang

Coal Geology & Exploration

In order to study the effect of pressure drop funnel shapes on CBM well productivity, the change law of pressure and the shape of pressure drop funnel in different drainage stages of CBM wells were discussed, the mathematical models of pressure drop funnel were established, the concept of "desorption coefficient" and "effective desorption coefficient" for coal reservoir were proposed to quantitative study desorption effect of the coal reservoir. Taking a CBM well in the west of Guizhou as an example, the research results show that the logarithmic function model of pressure distribution of radial flow is difficult to accurately reflect …