Characteristics of microseismic waveforms induced by hydraulic fracturing in coal seam for coal rock dynamic disasters prevention

Li, Nan; Huang, Bingxiang; Xin, Zhang; Tan, Yuyang; Li, Baolin

doi:10.1016/j.ssci.2019.01.024

Cited by 52 publications

(16 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Numerous researches have been carried out to investigate the permeability enhancement mechanisms and technologies of coal reservoirs, and measures such as hydraulic ushing, hydraulic fracturing, blasting loosening and advanced borehole have been taken. [8][9][10][11] Although these measures achieved a certain effect, but they require a large engineering quantity and can hardly be applied in several mining areas. To resolve this problem, enhanced coalbed methane (ECBM) recovery by gas injection (that is, injecting some gases, such as N 2 or CO 2 , into coal seams to displace CBM and promote CBM recovery) has been widely adopted and become a research hotspot worldwide.…”

Section: Introductionmentioning

confidence: 99%

A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N₂ injection: experimental observations and numerical simulation

Zhang

Ding

et al. 2021

RSC Adv.

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 99%

A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N₂ injection: experimental observations and numerical simulation

Zhang

Ding

et al. 2021

RSC Adv.

View full text Add to dashboard Cite

show abstract

“…A coal and rock feature recognition method based on the time-domain index of acoustic pressure data was proposed by Xue et al [ 21 ]. The latest signal processing methods include Wavelet Transform (WT) [ 22 ], Empirical Mode Decomposition (EMD) [ 23 ], Ensemble Empirical Mode Decomposition (EEMD) [ 24 ], Empirical Wavelet Transform (EWT) [ 25 ], and Variational Mode Decomposition (VMD) [ 26 ]. To address the shortcomings of Fourier Transform (FT) and Wavelet Transform (WT) signal processing methods in coal and rock recognition, Wei et al proposed an improved Empirical Variational Mode Decomposition (EVMD) method for ultrasonic echo signal processing [ 27 ].…”

Section: Introductionmentioning

confidence: 99%

Coal and Rock Hardness Identification Based on EEMD and Multi-Scale Permutation Entropy

Liu

et al. 2021

Entropy

View full text Add to dashboard Cite

This study offers an efficient hardness identification approach to address the problem of poor real-time performance and accuracy in coal and rock hardness detection. To begin, Ensemble Empirical Mode Decomposition (EEMD) was performed on the current signal of the cutting motor to obtain a number of Intrinsic Mode Functions (IMFs). Further, the target signal was selected among the IMFs to reconstruct the current signal according to the energy density and correlation coefficient criteria. After that, the Multi-scale Permutation Entropy (MPE) of the reconstructed signal was trained by the Adaboost improved Back Propagation (BP) neural network, in order to establish the hardness recognition model. Finally, the cutting arm’s swing speed and the cutting head’s rotation speed were adjusted based on the coal and rock hardness. The simulation results indicated that using the energy density and correlation criterion to reconstruct the signal can successfully filter out noise interference. Compared to the BP model, the relative root-mean-square error of the Adaboost-BP model decreased by 0.0633, and the prediction results were more accurate. Additionally, the speed control strategy based on coal and rock hardness can ensure the efficient cutting of the roadheader.

show abstract

“…e hard roof suspension structure is not easy to collapse, which will lead to an increase in the peak value of the advanced abutment stress and the effect range [1,2]. When the mining panel is close to the dip roadway, if the size of the reserved coal pillar is insufficient, the energy released by the roof fracture and the mining stress will have a serious impact on the remote roadway [3][4][5].…”

Section: Introductionmentioning

confidence: 99%

Study on Stress Relief of Hard Roof Based on Presplitting and Deep Hole Blasting

Gong

Chen

et al. 2020

Advances in Civil Engineering

View full text Add to dashboard Cite

For the problem that the hard roof causes wider end-mining coal pillar, and the roadway is greatly affected by mining, this paper took Shanxi Luning Coal Mine as the engineering background; based on the stress distribution characteristics of the coal pillar, the calculation method of the limit end-mining coal pillar size was given; considering the formation conditions and transmission forms of the advanced abutment stress, a method combining presplitting and deep hole blasting was proposed to weaken the advanced abutment stress. The numerical simulation was used to analyze the stress distribution of coal pillars, which was verified by on-site industrial tests. The results showed that the presplitting can achieve the blocking of stress. The closer it is to the peak of the abutment stress, the better the blocking effect. Deep hole blasting can weaken the source of the advanced abutment stress and reduce the peak of abutment stress. With the combination of the two blasting methods, the end-mining coal pillar size of Luning Coal Mine can be reduced to 60 m. The method combining presplitting and deep hole blasting can effectively reduce the end-mining coal pillar size and reduce the impact of mining on the deformation of the dip roadway.

show abstract

Characteristics of microseismic waveforms induced by hydraulic fracturing in coal seam for coal rock dynamic disasters prevention

Cited by 52 publications

References 29 publications

A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N₂ injection: experimental observations and numerical simulation

A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N₂ injection: experimental observations and numerical simulation

Coal and Rock Hardness Identification Based on EEMD and Multi-Scale Permutation Entropy

Study on Stress Relief of Hard Roof Based on Presplitting and Deep Hole Blasting

Contact Info

Product

Resources

About

Characteristics of microseismic waveforms induced by hydraulic fracturing in coal seam for coal rock dynamic disasters prevention

Cited by 52 publications

References 29 publications

A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N2 injection: experimental observations and numerical simulation

A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N2 injection: experimental observations and numerical simulation

Coal and Rock Hardness Identification Based on EEMD and Multi-Scale Permutation Entropy

Study on Stress Relief of Hard Roof Based on Presplitting and Deep Hole Blasting

Contact Info

Product

Resources

About

A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N₂ injection: experimental observations and numerical simulation

A dynamic evolution model of coal permeability during enhanced coalbed methane recovery by N₂ injection: experimental observations and numerical simulation