1087results about "Gas removal" patented technology

The invention relates to a coal seam extraction drilling air bag type memory metal net cover hole collapse prevention device and method, the device comprises an I-type air bag net cover installation unit body, a plurality of II-type air bag net cover installation unit bodies and an inflator pump, an exhaust pipeline is provided with an exhaust control valve, a hole wall is supported through a memory metal net cover, and the air bag net cover installation unit body and the inflator pump are arranged in the hole wall; the memory metal net sleeves can be matched with drill holes with different hole diameters in a self-adaptive mode and can be repeatedly used, the configuration number of the memory metal net sleeves can be greatly reduced, and therefore the processing cost of hole collapse prevention is further reduced; the installation of the memory metal net sleeve is directly controlled by the expansion of the air bag, so that the memory metal net sleeve can be quickly unfolded and reliably contacted with the hole wall; the removal of the memory metal net sleeve is directly controlled by temperature control gas, so that the memory metal net sleeve retracts to an initial state at the recovery temperature and is separated from the hole wall; the mounting and dismounting process of the memory metal net cover has the advantages of being simple, efficient and easy to operate, and the construction efficiency can be further improved.

The invention provides a coal mine gas extraction management and control method and system based on transparent geology, and the method comprises the following steps: integrating multi-source geological data, and constructing a transparent geological model which can reflect the actual geological condition in real time; based on geological information provided by the transparent geological model, calculating and optimizing key parameters of a drill hole in combination with coal and rock seeing parameters of a constructed drill hole to obtain preset drill hole design parameters; construction parameters and drilling parameters of drilling machine equipment are collected in real time; the drilling parameters are compared with the preset drilling design parameters; meanwhile, the drilling construction quality is analyzed and evaluated according to the construction parameters and the drilling parameters; and an extraction effect evaluation model and an extraction effect prediction model are constructed, gas parameters are collected in real time, and the gas extraction effect is evaluated. By means of the transparent geologic model, intelligent control over the whole coal mine gas extraction process is achieved.

The invention discloses a coal seam group occurrence three-area linkage gas extraction method. Firstly, a coal seam is divided into an underground coal gasification area, a pressure relief permeability increasing area and an original extraction area; in the initial stage of underground coal gasification, in the process that high-temperature combustible gas generated by underground coal gasification is injected into a ground drilling well, the high-temperature combustible gas and a coal body are subjected to heat transfer, so that the temperature of the coal body is increased, and gas desorption is enhanced; under the continuous coupling action of high temperature and high pressure of the high-temperature combustible gas, the permeability of the coal body is improved; in the process that high-temperature combustible gas is injected into the ground drilling well, gas extraction is continuously conducted on other adjacent drilling holes; under the condition that gas injection and gas extraction are sequentially and circularly performed in ground drilling, the coal body is circularly impacted by positive pressure-negative pressure alternating aerodynamic force, and further fracturing of the coal body is facilitated; under the triple effects of high-temperature coal body gas desorption strengthening, coal body permeability increasing and gas displacement, large-flow and high-quality extraction of deep coal seam gas is finally achieved.

The invention relates to the technical field of coal bed gas development and gas extraction, in particular to an electrodialysis-liquid CO2 time sequence synergistic anti-reflection method and system. Comprising an electrodialysis pretreatment stage, a CO2 synergetic permeability increasing stage and a process regulation and energy recovery stage, a mixed solution is injected into a coal seam in a pulse injection mode, and energy recovery is conducted through pipeline fluid pressure in the injection stopping period. According to the technical scheme, through multi-stage cooperation of electrodialysis pretreatment, CO2 phase change fracturing and pulse consolidation and regulation, accurate transformation of the coal seam low-permeability area is achieved. According to the scheme, electrodialysis is utilized to drive an acidic working solution to target and migrate to a difficult-to-permeate area, mineral substances are dissolved, and pores are expanded; then, high-energy expansion stress is generated through liquid CO2 phase change, and a through fracture network is formed; and finally, a pulse injection and energy recovery mechanism is adopted, fracture closing is restrained, system energy consumption is reduced, and therefore the coal seam breathability and the gas extraction efficiency are integrally improved.

The utility model relates to the technical field of gas extraction, in particular to an underground gas extraction blowout preventer, and mainly solves the technical problems that the existing gas extraction blowout preventer is high in spewing control difficulty, high in safety risk and high in sprayed slag cleaning workload. The device comprises a movable chassis, a deslagging box, a multi-way pipe, a drilling machine through pipe, a coal seam drilling pipe, a negative pressure pipe, a pressure relief buffer cover, a deslagging pipe and a pressure sensor. According to the device, gushing is detected through the pressure sensor, on-off of the negative pressure pipe and the slag discharging pipe is controlled in a feedback mode, dependence on manual experience is not needed, it can be guaranteed that gushing and corresponding equipment are started consistently, and the gushing control difficulty is greatly reduced; meanwhile, water and residual materials for slag spraying can be discharged into the slag discharging box through the slag discharging pipe in time to be collected, and the workload of slag spraying and cleaning is reduced; the device is further provided with a pressure relief buffer cover, when the pressure is too large due to gushing, buffering can be conducted through the pressure relief buffer cover, and damage to the device caused by the too large pressure is avoided.

The invention discloses a gas extraction dynamic regulation and control system and method based on three-dimensional modeling, and relates to the technical field of three-dimensional modeling, and the method comprises the steps: constructing an underground multi-source sensor network, and collecting underground gas extraction multi-modal data flow; the method comprises the following steps: acquiring an underground gas historical extraction data set, performing dynamic early warning analysis in combination with an underground gas extraction multi-modal data flow, and establishing a gas emission abnormity early warning model and an extraction system failure early warning model; self-adaptive fusion modeling is carried out, and a three-dimensional model of the extraction drilling system is generated; and the gas emission abnormity early warning model and the extraction system failure early warning model are mapped to the extraction drilling system three-dimensional model for extraction regulation and control analysis to determine target gas extraction control parameters, and extraction closed-loop regulation and control are carried out. The technical problem of monitoring and regulation response lag caused by gas extraction data islanding in the prior art is solved, and the technical effects of real-time sensing, intelligent early warning and accurate regulation in the gas extraction process are achieved.

The invention relates to the technical field of mine underground equipment, in particular to crawler-type high-gas coal seam drilling equipment based on a double-channel drill rod, which comprises a walking chassis, the double-channel drill rod, a hydraulic slotting system and a negative pressure deslagging device. Crawler-type composite drilling equipment is provided, process integration is carried out through breakthrough of three core technologies, directional drilling (a diamond drill bit and a spiral groove drill rod), hydraulic slotting and negative pressure deslagging are integrated into single equipment, the working procedure switching time is shortened, synchronous slotting and deslagging operation is achieved through a double-channel drill rod, and the working efficiency is improved. The problems of energy consumption and blockage are solved; and meanwhile, gas accidents are prevented.

The invention relates to the field of coal seam anti-reflection, and particularly discloses a coal seam carbon dioxide and static expanding agent synergistic anti-reflection system and method. Slurry prepared by mixing a static expanding agent and water is injected into the expansion fracturing drill hole, in the process that the static expanding agent is subjected to hydration reaction and generates expansion stress, carbon dioxide gas is injected into the expansion fracturing drill hole through the carbon dioxide gas injection pipe, carbon dioxide and the hydration product of the static expanding agent are subjected to carbonization reaction to generate larger expansion stress, and the expansion fracturing drill hole is formed. Expanding the coal body fractures to form expansion fractures; the carbon dioxide is driven by differential pressure to seep into a coal matrix along expansion fractures, and adsorbed gas is driven to be desorbed into a free state through a competitive adsorption effect; and under the combined action of extraction negative pressure and carbon dioxide displacement, the free-state gas moves from the fracture channel to the extraction drill hole, and extraction is conducted through the gas extraction system. Carbon dioxide and the static expanding agent cooperate to improve permeability of the coal body, the displacement effect of carbon dioxide on gas is promoted, and the gas extraction effect is improved.

The invention discloses an intelligent and accurate regulation and control multi-method collaborative fracturing intensified gas extraction method and system, and the method achieves the dynamic and accurate adjustment of parameters such as borehole arrangement, hydraulic fracturing strength and ultrasonic frequency through an intelligent regulation and control algorithm based on monitoring geological parameter feedback and a parameter self-adaptive adjustment technology. The optimal gas extraction scheme can be implemented according to different coal seam geological conditions, and the accuracy and efficiency of gas extraction are remarkably improved. The coal seam anti-reflection method is simple in construction process and easy and convenient to operate, the defects of a single anti-reflection technology can be effectively overcome, the advantages and disadvantages of anti-reflection measures are complementary, the coal seam anti-reflection effect is effectively improved, efficient mining and utilization of gas resources are achieved, safe and efficient production of a mine is powerfully guaranteed, and remarkable economic benefits and social benefits are achieved.

The invention discloses a ground single-hole multi-branch water jet radial coal breaking and permeability increasing extraction method, which comprises a directional drilling system, a filling system, a water jet coal breaking system, a deslagging system and a gas extraction system, and is characterized in that a vertical drilling hole is constructed on the ground, a centralizer and a whipstock are arranged at a coal seam junction, and a drill bit deflects to enter a coal seam construction horizontal branch drilling hole; three horizontal branch drill holes are constructed in each coal seam, the included angle is 120 degrees, after horizontal branch drill hole construction is completed, water jet coal breaking is carried out once every time a drill rod is withdrawn, coal seam air permeability is improved until all the drill rods are withdrawn, the process is repeated, drilling and water jet coal breaking work is carried out on other horizontal branch drill holes, and drill rods and drilling tools are withdrawn after all the work is completed. And the flange of the ground casing pipe is connected into an extraction system. The gas extraction work of the ground drilling coal seam group is realized; drill retreating and water jet coal breaking are carried out synchronously, and the air permeability of a coal seam is improved; gas extraction work of the coal seam group is achieved through ground drilling, and the gas control level is improved.

The invention discloses a coal face upper corner gas block extraction system which comprises an advancing mechanism, an extraction mechanism and a control mechanism. The extraction mechanism realizes goaf state monitoring and gas extraction; and the control mechanism controls the received signal to perform data analysis and processing, and reasonably issues an extraction instruction. The invention further discloses a coal face upper corner gas block extraction method. The method comprises the steps that coal face goaf extraction parameters are determined; installing an extraction system on site; starting each electric appliance part; completing information collection and processing to obtain an analysis result; a related action instruction is given according to the analysis result, adjustment of the extraction position is completed, and then gas extraction of the current area is completed; when the gas concentration of the goaf meets the safety standard, it is confirmed that extraction is completed. The invention belongs to the technical field of coal mine gas extraction and solves the problems that existing extraction equipment is unreasonable in structure and cannot extract gas in time.

The invention provides a high-temperature nitrogen synergistic liquid carbon dioxide coal seam anti-reflection effect evaluation method which comprises the steps that an injection hole and a plurality of extraction holes are formed in a target coal seam, and high-temperature nitrogen synergistic liquid carbon dioxide is injected into the injection hole for coal seam anti-reflection; monitoring data in the coal seam anti-reflection process are collected through a sensor arranged on the target coal seam; the monitoring data comprises a temperature gradient of the coal seam, a micro-seismic event of an area where the coal seam is located and gas concentration obtained through extraction; based on the monitoring data, through an LSTM stage identification model, determining different stages of the coal seam anti-reflection process and evaluation values corresponding to the core indexes and the dynamic response indexes in the different stages; the different stages are a carbon dioxide phase change stage, a nitrogen thermal stress fracturing stage and a stable extraction stage; under the condition that the evaluation value meets a preset evaluation condition, the evaluation grade of the permeability increasing effect of the target coal seam is determined; through the technical scheme, the evaluation result can be more scientific and objective.

The present application provides a kind of slotted equipment for coal seam gas control, belong to coal seam gas control technical field, including two slotted mainframes of synchronous coordination work, two slotted mainframes are arranged in the roadway of coal seam two sides respectively, and two slotted mainframes are driven connection through annular cutting cable between two slotted mainframes;Slotted mainframe includes self-propelled platform, power module, speed reducer, gear reversing device and main drive line wheel are set in self-propelled platform upper portion, power module passes through speed reducer and transmits power to gear reversing device;The present application uses annular cutting cable of cyclic motion as cutting force, and combines the feeding force provided by two slotted mainframes of synchronous coordination work, can cut out one or two slotted in coal seam transversely, instead of traditional high-density drilling, not only greatly reduces labor intensity, saves cost, and the permeability area formed by slotted is larger, more conducive to the desorption of gas, to greatly improve gas extraction efficiency.

The invention discloses an efficient drilling system for coal seam gas extraction drilling and a regulation and control method, fine crushing of particles in a chip returning process and efficient transportation and blockage removal of returned chip particles are realized by utilizing the crushing effect and the transportation effect of a spiral blade, and meanwhile, working condition parameters of a drill rod and the particle size and the quality after returned chips are crushed can be dynamically monitored; according to the method, key parameters are determined by analyzing GRA through the grey correlation degree through quantitative evaluation of the returned chip crushing effect, and then the returned chip crushing effect is predicted through a GA-BP neural network according to different drilling parameter combinations. And finally, an automatic control signal is output according to the returned chip crushing effect evaluation index error to dynamically regulate and control the drilling parameters so that the returned chip effect can reach the expected target, and efficient crushing and intelligent regulation and control in the drilling process can be achieved on the premise that the probability that a drill hole is blocked by coal rock returned chips in the drilling process is reduced. And the problem caused by blockage of the drill hole due to returned chips can be fundamentally solved, so that the hole forming efficiency of the gas extraction drill hole is improved.

The invention discloses an active treatment method for multi-source residual coal gas of a waste mine, which comprises the following steps: firstly, hydraulic fracturing pressure relief permeability improvement and overlying strata separation layer grouting reinforcement are cooperated, the hydraulic fracturing pressure relief permeability improvement establishes a netted fracture network in a coal body to realize permeability improvement, and the overlying strata separation layer grouting reinforcement compacts goaf gangue through grouting and reinforces an overlying strata to form a continuous bearing consolidation body; and therefore, a pressure relief and permeability increasing-strengthening and reinforcing integrated structure is formed, a stable structure and a penetrating seepage network are provided for subsequent displacement and gas extraction, and the subsequent gas extraction efficiency is guaranteed. Then low-temperature liquid CO2 is injected into the coal seam through the injection well, gas displacement and desorption are conducted on gas adsorbed in the coal seam under the action of phase change and competitive adsorption, expansion and development are conducted on fractures to enable permeability to be secondarily enhanced, and meanwhile part of CO2 obtained after displacement is retained and sealed in a coal body and a goaf; on the premise that the gas extraction concentration and efficiency are effectively improved, CO2 can be stored, and the dual effects of resource utilization and carbon storage are achieved.

The invention discloses a dust removal and safety guarantee integrated system for coal mine underground drilling. Comprising a mining multi-parameter sensor, an electromagnetic pneumatic valve controller, a cyclone dust collector, a dry bag-type dust collector, a gas drainage pipeline, a dust extraction pipeline, a hole sealing dust extraction cover, a compressed air conveying pipe, an electromagnetic pneumatic valve, a front-stage air ejector, a rear-stage air ejector and an air extraction air ejector. The hole sealing dust extraction cover captures drilling dust, the drilling dust enters the cyclone dust collector through the dust extraction pipeline to separate large particles, and air outlet of the drilling dust is divided into two ways: the first way is connected with the gas drainage pipeline through the air extraction air ejector to convey harmful gas, and the second way is connected with the dry bag-type dust collector to filter fine particles. The mining multi-parameter sensor monitors the concentration, the pressure difference, the temperature and the humidity of CH4, CO and CO2, the electromagnetic pneumatic valve controller dynamically switches gas circuits based on data, dust collection, gas drainage, water isolation and fire prevention and control are achieved, the drilling operation safety and the environment quality are remarkably improved, and the device is suitable for a high-gas mine.

The invention discloses a fractured zone gas extraction technology optimization method based on absolute gas emission amount, and relates to the technical field of coal mine gas extraction, and the method comprises the following specific steps: constructing a coal seam mining three-dimensional stratum model, reproducing a coal seam excavation overlying strata fracture dynamic development process, representing an overlying strata void ratio spatio-temporal evolution law by using an image processing technology, and obtaining a fractured zone gas extraction result. Obtaining an overlying strata void ratio distribution function; the permeability distribution is deduced, the gas emission amount of the working face is calculated, the gas seepage process in a fracture network is simulated, and a fractured zone gas control targeted area is delineated; a linkage control rule of extraction technical parameters on gas emission, migration and distribution is disclosed, and a fissure zone gas extraction technical library is constructed; and defining an absolute gas emission critical threshold applicable to the extraction technology, constructing a multi-factor hierarchical extraction technology optimization judgment criterion taking the absolute gas amount as a core and considering an occurrence mode, a coal mining method and a ventilation mode, and further providing an adaptive extraction technical scheme and a parameter optimization suggestion for a specific working face. According to the method, differentiated treatment of gas emission of the working face is achieved, the coal mine gas extraction effect is effectively improved, and a reference basis is provided for selecting a gas extraction technology according to local conditions.

According to the mechanical cave-making and permeability-increasing intelligent drilling robot for the coal mine, during cave-making and permeability-increasing work, a power output end drives a first power transmission unit, a second power transmission unit and a drill rod to rotate, hydraulic cave-making work is carried out, and once the drill is stuck due to hole collapse or components on the drill rod are hit into a hard rock mass, the drill rod is driven to rotate; when the drill rod connected with the motor is stuck, the continuously output power output end can drive the first power transmission unit to continuously rotate until the transmission pile and the locking tongue are fractured and the whole transmission pile idles in the positioning groove, and when the drill rod connected with the motor is stuck, through the fracture design of the transmission pile and the locking tongue of the anti-sticking module, the anti-sticking module can lock the drill rod. The overload damage risk is transferred to the replaceable module, burnout of the motor is avoided, and when a hole collapses to block a drill or components on a drill rod hit hard rock mass, the power source motor is not prone to being blocked and short-circuited, and the cave-building permeability-increasing construction process is not prone to being affected.

The invention discloses a directional long drill hole continuous drainage extraction promoting device and method, and relates to the technical field of coal mine underground gas extraction, the directional long drill hole continuous drainage extraction promoting device comprises a hole protection pipe, a drainage pipe, a drainage valve and an extraction pipeline, the extraction pipeline is connected with the hole protection pipe, the interior of the hole protection pipe is connected with the drainage pipe through welding rods, and the welding rods between the drainage pipe and the hole protection pipe are distributed in the radial direction; the multiple welding rods are axially distributed along the drainage pipe, and the end of the drainage pipe is connected with the drainage valve. According to the directional long drilling continuous drainage pumping promoting device and method, automatic response is achieved, manual intervention is not needed, the material A and the material B can be automatically switched according to the water accumulation state, manual judgment or operation is not needed, and the directional long drilling continuous drainage pumping promoting device and method adapt to the complex drilling environment and are particularly suitable for deep long drilling; the structure is stable and reliability is high.

A hydrogen production system for producing a hydrogen gas product includes a geologic hydrogen source configured to provide a feedstock comprising hydrogen, nitrogen, and helium and purification equipment comprising two or more of: a pressure swing adsorption (PSA) device; a guard bed; a separation membrane; a reactive membrane; or a cryogenic separation device. The purification equipment is configured to receive the feedstock from the geologic hydrogen source and produce a hydrogen gas product, and production of the hydrogen gas product exhibits a carbon intensity score less than 3.0 kg CO2 eq / kg H2.

The invention discloses a CO2 directional fracturing target layer crack propagation simulation control method based on flow regulation and control. The method comprises the steps that a plurality of experimental coal samples are manufactured, and drill holes are formed; the fracturing pump inputs CO2 with set flow into the coal sample through the CO2 injection pipeline; the high-frequency dynamic pressure sensor collects fluid pressure data in the coal sample crack; the acoustic emission sensor monitors and obtains the crack initiation moment and crack initiation pressure of the coal sample; the method comprises the following steps: carrying out cracking and crack width monitoring on a coal sample, calculating a theoretical value of crack initiation pressure and a theoretical value of CO2 injection flow of the coal sample, injecting supercritical CO2 fluid into the coal sample, obtaining a first-stage correction coefficient and a second-stage correction coefficient of the CO2 injection flow, and calculating a corrected CO2 injection flow value. According to the method, under the multi-physical-field coupling environment, the crack initiation pressure of the coal body can be accurately measured and calculated, the correlation between the CO2 injection flow and the crack width of the coal body is established, and the CO2 injection flow better meets the actual requirements of field operation through a CO2 injection flow grading correction mechanism.

The invention discloses a method and a device for determining the gas content of a coal body by using tunneling face gas emission parameter inversion, and relates to the technical field of coal mine gas detection and safety. The method comprises the following steps: acquiring gas concentration, wind speed, roadway section parameters, geological parameters and environmental parameters of a tunneling face through a multi-parameter dynamic acquisition system; on the basis of the collected parameters, gas emission quantity characteristic values are calculated according to drilling operation shifts and non-drilling operation shifts through a dynamic inversion algorithm, and the gas content of the coal body in the current area is inversed; a coal sample is collected through an underground one-stop measuring system, the accurate gas content is measured, and parameters of a dynamic inversion algorithm are optimized; and inputting the multi-source data into an intelligent inversion and early warning system to obtain a predicted value of the gas content in front of the tunneling face and a gas outburst risk level, and adjusting the acquisition frequency and an inversion model. A measurement closed loop is formed, the measurement accuracy and timeliness of the gas content are improved, and the safety of coal mine tunneling operation is guaranteed.

The invention discloses a zero-carbon method for strengthening coal seam gas recovery and CO2 storage by using flue gas residual heat in the technical field of residual heat utilization, gas extraction and carbon emission reduction. The zero-carbon method comprises the following steps: step 1, collecting high-temperature flue gas in a power plant; step 2, performing high-temperature CO2 concentration-compression; step 3, reservoir evaluation and area selection; 4, designing and constructing a horizontal well; 5, high-temperature CO2 injection and joint control energy increasing are conducted, specifically, high-temperature CO2 is injected into a preset section through a pump, the injection pressure and the injection speed are adjusted through the joint control energy increasing technology, and the diffusion range and the diffusion speed of CO2 are controlled; 4, gas recovery and CO2 storage: high-temperature CO2 is used for providing energy to promote gas desorption on one hand, and the high-temperature CO2 and CH4 in the adsorption state are subjected to competitive adsorption on the other hand. The method is simple and easy to operate, the coal seam gas partial pressure is reduced through CO2 injection, the recovery efficiency is improved, CO2 can be adsorbed by a coal seam and stored in a reservoir, and geological storage of CO2 is achieved.

The invention discloses a digging and anchoring surface'pressing-pumping-spraying 'intelligent cooperative dust control and removal experiment platform, which comprises an operation simulation system, a dust removal simulation system and an intelligent centralized control system, and is characterized in that the intelligent centralized control system comprises an industrial personal computer, and the industrial personal computer is used for driving and adjusting the operation simulation system and the dust removal simulation system; the operation simulation system comprises a digging and anchoring all-in-one machine and a belt conveyor, a plurality of groups of sensors are arranged in the roadway at intervals, each group of sensors comprises a roadway dust concentration sensor and a roadway gas concentration sensor, and the detection output end of each roadway dust concentration sensor is connected with the roadway dust detection signal input end of the industrial personal computer. The detection output ends of the roadway gas concentration sensors are connected with the roadway gas detection signal input end of the industrial personal computer; the dust removal simulation system comprises a pressure fan, a dust removal fan and a local pressure fan. Different working conditions can be simulated and verified, and an efficient, accurate and dynamically optimized comprehensive treatment scheme can be obtained.

The invention discloses an impact-outburst hybrid dynamic disaster prediction method based on energy chain type evolution, and relates to the technical field of coal mine underground dynamic disaster prediction. According to the method, roadway impact-outburst hybrid dynamic disaster energy under different surrounding rock mechanical parameters, gas parameters and impact load parameters is solved through automatic numerical simulation, and an impact-outburst hybrid dynamic disaster energy data set under various working conditions is automatically constructed. The invention provides a CNN-LSTM-Attention roadway impact-outburst hybrid dynamic disaster energy prediction model with energy and spatial feature constraints, the CNN model extracts roadway spatial features, the LSTM model obtains an energy sequential sequence, Attention automatically allocates space-time double-region attention mechanism weights, the three models are cooperatively fused, and the energy prediction efficiency of the roadway impact-outburst hybrid dynamic disaster energy prediction model is improved. And the energy prediction accuracy of the roadway impact-outburst hybrid dynamic disaster is improved.

The utility model discloses an intelligent blowout prevention device based on a PLC control system, and relates to the technical field of blowout prevention during coal drilling, a slag baffle and an annular inner tube allowing a drill rod to penetrate through are arranged in a four-way pipe, the annular inner tube is connected with an external air source, a methane sensor used for detecting the concentration of methane near a drilled hole is arranged in a roadway, and the external air source is connected with an external air source. The PLC control cabinet is connected with the methane sensor and the external gas source, when hole spraying occurs, the pressure of gas in a drill hole is increased, the gas in the drill hole is diffused to the position near the drill hole through a gap between the drill rod and the four-way pipe, and after the concentration of the methane near the drill hole reaches a preset threshold value of the methane sensor, the PLC control cabinet controls the external gas source to supply gas to the annular inner tube. The annular inner tube expands towards the middle to tightly hold the drill rod, the path that gas in the drill hole continues to escape to the position near the drill hole through the gap between the drill rod and the four-way pipe is cut off, and the problem that normal work in a roadway is affected due to the fact that gas in the drill hole continues to escape through the gap between the drill rod and the four-way pipe is solved.

The invention discloses a large-dip-angle coal seam group coal roadway strip advanced fracturing and gas extraction method, and relates to the technical field of coal mine gas extraction. The method comprises the following steps: arranging a crossing hydraulic fracturing drill hole in an overlying first coal seam roadway to form an anti-reflection crack; a directional long drill hole of the coal seam is formed in the position of a to-be-tunneled roadway of the underlying coal seam, and strip advanced fracturing is formed based on the fracture extending direction; and ordered connection of drilling construction, gas pre-pumping, roadway tunneling and simultaneous tunneling and pumping is realized through closed-loop operation. The drilling distance, the hole sealing length and the pump injection parameters are optimized, the gas extraction period is remarkably shortened, the coal wall gas emission amount is reduced, and the tunneling efficiency is improved. According to the method, the problems of low gas extraction efficiency and high safety risk of the large-dip-angle coal seam group are effectively solved through a combination mode of gas extraction and strip advanced fracturing, the method is suitable for various coal seam conditions, and the safety and sustainability of coal mine production are remarkably improved.

The application discloses a through-layer drilling ring flow supply self-cleaning and blocking integrated hole bottom extraction non-jetting drill tool, which comprises a multifunctional rod body, an extraction inner group pipe, a radial cavity forming nozzle, an axial blocking nozzle, a conical hole screen plate strip, an air inlet transition piece, a cross-border air inlet pipe, a compression spring slide valve assembly and a ring flow opening and closing drill bit. The special slide valve control mechanism is adopted, the original radial cavity forming jet flow is reserved, and the instantaneous axial blocking jet flow is added, so that the conical hole screen plate strip is self-cleaned and blocked. The cross-border air inlet pipe and the transition air inlet piece are combined and sealed, so that the radial air inlet channel passes through the axial flow supply channel without air and water leakage. The ring flow supply anti-backflow opening and closing drill bit is designed, and the jet flow water medium pollution problem and the drill bit opening and closing problem are solved.

The invention relates to the technical field of coal mine gas control and CO2 geological storage, and particularly discloses a soft coal seam dynamic fracture self-adaptive CO2 displacement-anti-reflection integrated system which comprises a dynamic fracture monitoring unit, a CO2 collaborative anti-reflection unit, a self-adaptive regulation and control unit and a safety protection unit. The dynamic fracture monitoring unit is used for capturing coal seam fracture development dynamics and gas injection process parameters in real time; the self-adaptive regulation and control unit is in communication connection with the dynamic fracture monitoring unit, and the CO2 synergistic anti-reflection unit is in control connection with the self-adaptive regulation and control unit and is used for realizing CO2 enhanced anti-reflection displacement; the safety protection unit is used for guaranteeing system operation safety. According to the method, real-time adaptation of the coal seam fracture state and the injection-production parameters is achieved, the problems that in a traditional fixed parameter mode, the displacement efficiency attenuation is fast, and the coal body stability is poor are solved, the CH4 recovery rate and the CO2 storage rate are increased, and the safety and high efficiency of soft coal seam gas control operation are guaranteed.

The invention discloses a coal mine gas extraction device, which relates to the technical field of gas extraction safety, and comprises an extraction pipe arranged in an extraction channel and connected with external extraction equipment; the sleeve is arranged on the outer side of the extraction pipe, the outer wall of the sleeve is attached to the extraction channel, an upper fixing ring is arranged on the top, and a lower moving ring and a sliding shaft sleeve are arranged on the lower portion; the pumping and drainage plugging device is fixed on the extraction pipe, and the outer side of the top is fixedly connected with the upper fixing ring; the bottoms of the limiting control devices are fixedly connected with the lower moving ring, the outer sides of the limiting control devices are fixedly connected with the inner wall of the sleeve, and the inner sides of the limiting control devices are fixedly connected with the pumping and drainage plugging device; the bottom of the plugging control device is fixedly connected with the lower moving ring, the outer side of the plugging control device is fixedly connected with the inner wall of the sleeve, and the inner side of the plugging control device corresponds to the side part of the pumping and draining plugging device. The gas drainage device has the gas drainage efficiency and the outburst early warning protection capacity, and integration of the pressure dynamic monitoring function, the quick response plugging function and the automatic reset function is achieved.