This page has only limited features, please log in for full access.

Unclaimed
Fakai Wang
College of Mining Engineering Guizhou Institute of Technology Guiyang China

Basic Info

Basic Info is private.

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Research article
Published: 06 September 2020 in Energy Science & Engineering
Reads 0
Downloads 0

Hydraulic methods have been extensively employed to improve the production rate of commercially viable coalbed methane and prevent potential mining disasters resulting from the production of this methane by increasing the permeability of coal seams. In this paper, an experimental system with a stirrer was utilized to study the effects of water injection on the gas desorption characteristics of coal seams. Pressure‐released desorption values and total gas desorption values under conditions of different adsorption equilibrium pressures and water contents were determined. The results show that both the free gas and the adsorbed gas could be replaced by the injected water, causing the system pressure to increase significantly. When releasing the system pressure, the gas desorption value of the water‐injected coal sample was reduced. After water injection, the total desorption value of the coal was increased. Thus, water injection could help to promote coal gas desorption.

ACS Style

Peng Li; Feng Du; Fakai Wang; Pan Zhang; Yuxiang Jiang; Bo Cui. Influence of water injection on the desorption characteristics of coalbed methane. Energy Science & Engineering 2020, 8, 4222 -4228.

AMA Style

Peng Li, Feng Du, Fakai Wang, Pan Zhang, Yuxiang Jiang, Bo Cui. Influence of water injection on the desorption characteristics of coalbed methane. Energy Science & Engineering. 2020; 8 (12):4222-4228.

Chicago/Turabian Style

Peng Li; Feng Du; Fakai Wang; Pan Zhang; Yuxiang Jiang; Bo Cui. 2020. "Influence of water injection on the desorption characteristics of coalbed methane." Energy Science & Engineering 8, no. 12: 4222-4228.

Journal article
Published: 20 November 2019 in Scientific Reports
Reads 0
Downloads 0

The prediction of dangerous hazards in working faces is an important link to prevent coal and gas outbursts. Improving the accuracy of predictive indicators is of great significance for reducing the phenomenon of being prominently below the critical value and ensuring safe production. The fixed-size desorption index K1 is one of the important indicators for coal face and gas outburst prediction. Based on the diffusion theory and the physical meaning of fixed-size coal samples, the mathematical expression of K1 is established by the self-developed high/low temperature pressure swing adsorption-desorption experimental system. According to the equation, the effects of gas pressure, loss time, coal particle size and diffusion coefficient on K1 are studied. The results show that the K1 index is logarithmically related to the gas pressure. Under the same conditions, the longer the loss time is, the smaller the measured K1 is, and the smaller the particle sizes of the drill cuttings are, the more notable the performance is; the diffusion coefficient represents the ability of gas to bypass micropores and the coal matrix. The greater the ability to bypass the matrix is, the larger the diffusion coefficient under the same conditions is, and the larger K1 is; the coal particle size has a greater influence on K1, and the smaller the size is, the more likely it is that the phenomenon of being prominently below the critical value occurs. Therefore, the particle size composition of coal during on-site measurements is crucial for obtaining the true K1 and the exact critical values.

ACS Style

Lei Li; Zhongguang Sun; Fakai Wang; Kaizhi Zhang. Study on the gas desorption law and indicator influencing factors of fixed-size coal samples. Scientific Reports 2019, 9, 1 -11.

AMA Style

Lei Li, Zhongguang Sun, Fakai Wang, Kaizhi Zhang. Study on the gas desorption law and indicator influencing factors of fixed-size coal samples. Scientific Reports. 2019; 9 (1):1-11.

Chicago/Turabian Style

Lei Li; Zhongguang Sun; Fakai Wang; Kaizhi Zhang. 2019. "Study on the gas desorption law and indicator influencing factors of fixed-size coal samples." Scientific Reports 9, no. 1: 1-11.

Articles
Published: 17 May 2019 in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects
Reads 0
Downloads 0

The zoning of the coal seam gas is zonal, which has a significant impact on the prominent prediction indicators, resulting in different prediction results for the same prominent prediction indicators in the same coal seam soft and hard coal. In this paper, the hard coal and soft coal in the coal seam are highlighted. The adsorption and desorption rules of the soft coal and hard coal in the outburst coal seam and its influence on the sensitivity of the outstanding prediction index are studied. The results show that: (1) the initial desorption of soft coal is larger than that of hard coal; (2) the outstanding prediction index has an exponential function relationship with gas pressure; (3) the sensitivity of prediction indicators is different. And concluded that: (1) the initial desorption rate of soft coal is faster than that of hard coal; (2) the outburst prediction index K1 and Δh2 increase with the increase of gas adsorption equilibrium pressure; (3) outburst prediction index K1 is more reliable than Δh2.

ACS Style

Zhongguang Sun; Lei Li; Fakai Wang; Guojun Zhou. Desorption characterization of soft and hard coal and its influence on outburst prediction index. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 2019, 42, 2807 -2821.

AMA Style

Zhongguang Sun, Lei Li, Fakai Wang, Guojun Zhou. Desorption characterization of soft and hard coal and its influence on outburst prediction index. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects. 2019; 42 (22):2807-2821.

Chicago/Turabian Style

Zhongguang Sun; Lei Li; Fakai Wang; Guojun Zhou. 2019. "Desorption characterization of soft and hard coal and its influence on outburst prediction index." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 42, no. 22: 2807-2821.

Research article
Published: 08 January 2019 in Energy Science & Engineering
Reads 0
Downloads 0

The permeability characteristics of gas‐containing coal under different radial stress, different axial stress, and gas pressure were studied by orthogonal experiments, using a self‐developed three‐axis servo fluid infiltration system with a gas‐solid coupling of gas‐containing coal, on the basis of a single‐factor influence on the permeability of gas‐containing coal. By considering the effective stress, three kinds of relationships between permeability and radial stress, permeability and axial stress, as well as permeability and gas pressure were established. The results show that radial stress, axial stress, and gas pressure have a great influence on the permeability characteristics of gas‐containing coal: (a) The influence of radial stress on gas permeability is significant, whereas the influence of axial stress is negligible. The degree of influence of radial stress, gas pressure, and axial stress on the permeability decreases in turn; (b) The permeability decreases following a power function with the increase of the radial stress; (c) The permeability gradually increases with the increase of axial stress. With the increase of axial stress, the permeability increases following a power function; (d) The increase in gas pressure will reduce the effective stress on the coal, and the number of pores and cracks inside the coal body will decrease. This will increase the effective seepage flow and gas flow rate of the gas and eventually lead to the increase of coal permeability. There is a quadratic function relationship between the permeability and gas pressure.

ACS Style

Fakai Wang; Yunpei Liang; Xuelong Li; Lei Li; Jiangong Li; Yulong Chen. Study on the change of permeability of gas-containing coal under many factors. Energy Science & Engineering 2019, 7, 194 -206.

AMA Style

Fakai Wang, Yunpei Liang, Xuelong Li, Lei Li, Jiangong Li, Yulong Chen. Study on the change of permeability of gas-containing coal under many factors. Energy Science & Engineering. 2019; 7 (1):194-206.

Chicago/Turabian Style

Fakai Wang; Yunpei Liang; Xuelong Li; Lei Li; Jiangong Li; Yulong Chen. 2019. "Study on the change of permeability of gas-containing coal under many factors." Energy Science & Engineering 7, no. 1: 194-206.

Journal article
Published: 14 November 2018 in Processes
Reads 0
Downloads 0

Coalbed gas content is the most important parameter for forecasting and preventing the occurrence of coal and gas outburst. However, existing methods have difficulty obtaining the coalbed gas content accurately. In this study, a numerical calculation model for the rapid estimation of coal seam gas content was established based on the characteristic values of gas desorption at specific exposure times. Combined with technical verification, a new method which avoids the calculation of gas loss for the rapid estimation of gas content in the coal seam was investigated. Study results show that the balanced adsorption gas pressure and coal gas desorption characteristic coefficient (Kt) satisfy the exponential equation, and the gas content and Kt are linear equations. The correlation coefficient of the fitting equation gradually decreases as the exposure time of the coal sample increases. Using the new method to measure and calculate the gas content of coal samples at two different working faces of the Lubanshan North mine (LBS), the deviation of the calculated coal sample gas content ranged from 0.32% to 8.84%, with an average of only 4.49%. Therefore, the new method meets the needs of field engineering technology.

ACS Style

Fakai Wang; Xusheng Zhao; Yunpei Liang; Xuelong Li; Yulong Chen. Calculation Model and Rapid Estimation Method for Coal Seam Gas Content. Processes 2018, 6, 223 .

AMA Style

Fakai Wang, Xusheng Zhao, Yunpei Liang, Xuelong Li, Yulong Chen. Calculation Model and Rapid Estimation Method for Coal Seam Gas Content. Processes. 2018; 6 (11):223.

Chicago/Turabian Style

Fakai Wang; Xusheng Zhao; Yunpei Liang; Xuelong Li; Yulong Chen. 2018. "Calculation Model and Rapid Estimation Method for Coal Seam Gas Content." Processes 6, no. 11: 223.

Research article
Published: 31 July 2018 in Energy Science & Engineering
Reads 0
Downloads 0
ACS Style

Fakai Wang; Jiangfu He; Yunpei Liang; Yongjiang Luo; Zhiwei Liao; Lei Li. Study on the permeability characteristics of coal containing coalbed methane under different loading paths. Energy Science & Engineering 2018, 6, 475 -483.

AMA Style

Fakai Wang, Jiangfu He, Yunpei Liang, Yongjiang Luo, Zhiwei Liao, Lei Li. Study on the permeability characteristics of coal containing coalbed methane under different loading paths. Energy Science & Engineering. 2018; 6 (5):475-483.

Chicago/Turabian Style

Fakai Wang; Jiangfu He; Yunpei Liang; Yongjiang Luo; Zhiwei Liao; Lei Li. 2018. "Study on the permeability characteristics of coal containing coalbed methane under different loading paths." Energy Science & Engineering 6, no. 5: 475-483.

Research article
Published: 07 June 2018 in Adsorption Science & Technology
Reads 0
Downloads 0

Coal and gas outburst is a dynamic phenomenon with violent eruptions of coal and gas from the working coal seam. It has been proved that the rapid desorption within a short period is necessary for the occurrence of an outburst. Due to limitation of the present test condition, gas desorption characterization for the first 60 s has not been researched sufficiently. In the present study, an experimental apparatus with the ability of high-frequency data collection was developed. Initial desorption characterization of methane and carbon dioxide in coal was experimentally studied. Both the initial desorption characterization of methane and carbon dioxide were experimentally studied with different equilibrium pressures. The desorbed gas pressure was measured at desorption time phase of 0–10 and 45–60 s, besides the initial amount of desorbed gas and initial diffusion velocity of coal gas were calculated to assess their risk of outburst. The results show that the gas pressure for both methane and carbon dioxide increases sharply in the initial time and then levels off, and the total amount of desorbed gas increases with the increasing desorption time. Although the amount of desorption methane is slightly larger than that of carbon dioxide at the beginning, the total amount of desorbed carbon dioxide is significantly larger than that of methane at the desorption process. Therefore, it can be concluded that the coal and carbon dioxide outburst is more dangerous than the coal and methane outburst based on the obtained experimental results.

ACS Style

Yunpei Liang; Fakai Wang; Yongjiang Luo; Qianting Hu. Desorption characterization of methane and carbon dioxide in coal and its influence on outburst prediction. Adsorption Science & Technology 2018, 36, 1484 -1495.

AMA Style

Yunpei Liang, Fakai Wang, Yongjiang Luo, Qianting Hu. Desorption characterization of methane and carbon dioxide in coal and its influence on outburst prediction. Adsorption Science & Technology. 2018; 36 (7-8):1484-1495.

Chicago/Turabian Style

Yunpei Liang; Fakai Wang; Yongjiang Luo; Qianting Hu. 2018. "Desorption characterization of methane and carbon dioxide in coal and its influence on outburst prediction." Adsorption Science & Technology 36, no. 7-8: 1484-1495.

Original articles
Published: 18 July 2017 in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects
Reads 0
Downloads 0

To improve the quality of anthracite disposed by fracturing technology, the dehydration characteristics of anthracite were studied experimentally. The influences of temperature and particle size were investigated. The results show that the drying temperature has significant effects on water loss rate. The higher the temperature is, the faster the growth rate decreases. The particle size has little effects on the water loss rate at the beginning of dehydration process. So compared with reducing the particle size, increasing the temperature can promote the dehydration of anthracite in initial stage. Smaller particle size benefits the dehydration process.

ACS Style

Han Wang; Fakai Wang; Yunpei Liang. Thermal drying dehydration and moisture migration in anthracite. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 2017, 39, 1518 -1524.

AMA Style

Han Wang, Fakai Wang, Yunpei Liang. Thermal drying dehydration and moisture migration in anthracite. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects. 2017; 39 (14):1518-1524.

Chicago/Turabian Style

Han Wang; Fakai Wang; Yunpei Liang. 2017. "Thermal drying dehydration and moisture migration in anthracite." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 39, no. 14: 1518-1524.