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Flat-bottom coal silo
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Mining area coal seam roof multi-branch horizontal well construction method
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Well drilling method for extracting coal bed gas of adjacent closed goaf group
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Method for extracting coal-bed gas well in inclined coal-bed goaf
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Photovoltaic and gas complementary power generation direct current drive oil pumping machine system
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Negative pressure automatic water drainage device for gas drainage pipeline
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Controllable fan reactive compensation frequency conversion starting drive of output amount of wind
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Method for segmented grouting of same grouting hole of underground mining face collapse column roadway
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Micro L-shaped long-life anti-damage well body structure of mining well and well drilling method thereof
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Coal mine mining area gas extraction method
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Coal reservoir and underlying goaf coalbed methane layered pressure control combined extraction method
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Method for solving hard top plate collapse problem through ground vertical hole composite jet fracturing
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Method for layered pressure control combined extraction of coal bed gas of goaf and underlying coal reservoir
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Underground mine dust efficient purification treatment device
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Pressurized liquid injection system and method for coal-bed gas well
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Coal-bed gas well coal dust prevention and drainage metering system and drainage metering and coal dust prevention method
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Method for determining length and set parameters of steel strip of welded spiral pipe
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Method for detecting benzoic acid in coal biodegradation product
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Method for intercepting gas extracted from directional long drill hole
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Method for controlling gas in one-end roadway of wind-cut driving working face during mine windward period
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