1944results about "Gas removal" patented technology

A downhole extraction pipeline blockage clearing system, comprising a blockage clearing apparatus (1), a direction changing and impurity removal integrated apparatus (2), an impurity removal apparatus (3), and a floating ball control mechanism; the blockage clearing apparatus (1) utilizes a self-advancing blockage clearing spray head (5), which has self-rotation and self-advancing functions and utilizes a high pressure jet to actively clean a pipeline, thus improving the efficiency and effect of blockage clearing; the direction changing and impurity removal integrated apparatus (2) can implement direction changing for and transport of the blockage clearing apparatus (1), conveniently adjusts the direction of entry of the blockage clearing apparatus (1) into an extraction pipeline, and adapts to different extraction pipeline arrangements; the impurity removal apparatus (3) can implement simultaneous online cleaning and impurity removal, improving blockage clearing efficiency and reducing manual operation; additionally, the floating ball control mechanism is also utilized, and a plurality of one-way valves are jointly controlled by means of buoyancy and changes in pressure differences, thereby implementing impurity removal automation. The extraction pipeline does not need to be closed during a blockage clearing procedure.

The invention relates to the technical field of data processing, and discloses a coal mine area gas control and safety guarantee method and system under complex geological conditions. The method comprises the steps that geophysical prospecting, drilling and logging exploration are conducted on a coal mine area, and geological parameters are obtained; performing statistical analysis on the data, and constructing a three-dimensional gas model; identifying a high-gas area based on the model, and arranging a directional drilling network; differential extraction and anti-reflection measures are implemented according to the drilling network; fusing extraction and sensor data, and predicting a gas change trend by using a neural network; and performing intelligent diagnosis based on the early warning matrix to form a disposal scheme. Under the complex geological condition, the gas distribution rule is accurately mastered, scientific arrangement of directional drilling and optimization design of differential extraction parameters are achieved, meanwhile, a gas early warning decision support system based on artificial intelligence is established, the accuracy of gas treatment and the timeliness of early warning are improved, and therefore safe production of a coal mine is guaranteed.

The invention relates to the technical field of gas extraction drilling machine vibration signal processing, in particular to a gas extraction drilling machine vibration signal self-adaptive noise reduction method based on multi-scale feature fusion. The method comprises the steps of collecting a vibration signal, converting the vibration signal into a two-dimensional waveform image, recognizing a drilling working condition area, constructing a multi-scale objective function to optimize VMD parameters, decomposing the signal and screening a dominant IMF component for reconstruction. Through multi-objective optimization and multi-feature fusion strategies of energy distribution and transient impact characteristics, the problems that in a traditional method, the noise reduction effect is poor, and the coal rock character recognition precision is insufficient are solved, the waveform similarity, the power spectrum density coincidence degree and the correlation coefficient are remarkably improved, and reliable guarantee is provided for coal mine safety production.

The present invention relates to a downhole extraction pipeline blockage clearing apparatus, comprising a frame, a hose wind-up apparatus, an advancing apparatus, a high pressure pump set, a hydraulic pipe, a self-advancing blockage clearing spray head, and a control system; the hose wind-up apparatus, the advancing apparatus, and the high pressure pump group are all connected to the control system and are controlled by the control system; the hydraulic hose is wound on the hose wind-up apparatus, and wind-up of the hydraulic hose is implemented by means of rotation of the hose wind-up apparatus; the advancing apparatus is located at one side of the hose wind-up apparatus, jointly moves with the hose wind-up apparatus, and holds and transports the hydraulic hose to enter into an extraction pipeline; one end of the hydraulic hose is connected to the high pressure pump group, and the other end is connected to the self-advancing blockage clearing spray head; and the self-advancing blockage clearing spray head performs blockage clearing within the extraction pipeline by means of a jet stream and by means of the high pressure pump group conveying high pressure water to the self-advancing blockage clearing spray head. The spray head of the present invention possesses self-rotation and self-advancing functions, the effect and efficiency of blockage clearing are improved, and manual operation becomes less intensive; and the hose wind-up apparatus and the advancing apparatus implement automated wind-up and transport of the hydraulic hose, preventing the hydraulic hose from becoming tangled and damaged.

A coal and gas outburst monitoring device includes the insertion and anchoring assembly, and the pump drainage and monitoring mechanism; the insertion and anchoring assembly is vertically inserted and distributed on the sidewall of surrounding rock of coal mine roadway, and the insertion and anchoring assembly can monitor the stress change data in the sidewall of surrounding rock in real time; the pump drainage and monitoring mechanism is erected within the coal mine roadway, and the pump drainage and monitoring mechanism can cooperate with the insertion and anchoring assembly to perform the gas pump drainage monitoring for the sidewall of surrounding rock of goaf, and to obtain the gas seepage monitoring data in the surface layer and the inner layer of sidewall of surrounding rock. Thus, comparing with the database mechanism, the accurate and advanced predictions for the gas outburst can be made.

The invention discloses a gas extraction drilling track inversion and control system, and relates to the technical field of gas extraction, and the key points of the technical scheme are that the system comprises a high-gas coal seam rapid control elimination and reduction system and a gas injection flow increasing dynamic evaluation system; according to the rapid control elimination and reduction system for the high-gas coal seam, a method of combining experimental research, numerical simulation and on-site industrial tests is adopted, the coal seam gas occurrence rule of a working face of a Chengne mining area is obtained, the multi-component gas competitive adsorption rule of a three-soft coal seam is defined, and therefore gas injection driving key technical parameters of a coal seam gas abnormal target area are mastered; a gas injection drive gas-carrying rapid and accurate extraction technical system suitable for the gas abnormal area of the Chengne mining area is formed; according to the gas injection flow increasing dynamic evaluation system, working parameters are designed and monitored, the gas concentration is accurately monitored, and real-time detection and automatic early warning are achieved.

Disclosed in the present invention is a method for draining water of coal mine goafs by crossing an adjacent goaf. An applicable environment of the method comprises a first goaf, a second goaf and a third goaf which are successively arranged on a side of a tunnel, directional drilling mechanisms being provided between the tunnel and the second goaf and between the tunnel and the third goaf, and the directional drilling mechanisms penetrating through a coal seam floor located at the bottom of the goafs so as to communicate with the second goaf and the third goaf. Directional holes comprise a first directional hole and a second directional hole, the first directional hole leading to the second goaf, the second directional hole leading to the third goaf, and a sleeve structure being mounted in the first directional hole. The present invention uses directional drilling, and the directional holes penetrate into and out of the coal seam floor, so as to cross the adjacent goaf, thus increasing the range of explored and drained goafs and the hole length so as to drain in advance water accumulated in the remaining goafs that cannot be drained in a traditional coal mine drilling mode. The present invention can be popularized and used in the field of coal mines to solve the present threat of goaf water to coal mine production.

The invention discloses an upward continuous blasting anti-reflection and extraction method for an inclined high-gas coal seam of a tunnel, and belongs to the field of tunnel gas control. The method comprises the following steps: S1, determining an outburst prevention control boundary of a high-gas coal seam in front of a tunnel face; s2, a first row of large-diameter extraction drill holes located on the uppermost portion of the outburst prevention control boundary are constructed on the tunnel face towards the coal seam, hole sealing operation is carried out, and then an extraction pipeline is connected for gas extraction; s3, a first row of blasting drill holes are constructed in the coal seam on the tunnel face, then blasting explosive columns are loaded into the first row of blasting drill holes, and the first row of blasting drill holes are detonated at the same time; s4, the first row of blasting drill holes are connected with a gas extraction pipeline, and gas extraction is conducted; s5, the steps S2-S4 are repeated, and construction, charging, blasting and extraction operation of the second row of large-diameter extraction drill holes and the second row of blasting drill holes are conducted till the lowest portion of the outburst prevention control boundary is achieved; therefore, the gas extraction effect can be enhanced, and the construction period of tunnel coal uncovering and coal seam crossing is greatly shortened.

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 belongs to the technical field of coal mine safety, and relates to drilling construction equipment with drilling cooperating with reciprocating impact and a coal seam gas extraction method. The impact fracturing assembly comprises an impact drill bit, a reciprocating impact rod and a rotary transmission rod; the middle of the reciprocating impact rod is slidably sleeved with a first positioning block. The reciprocating impact rod is provided with a straight groove arranged in the axial direction, and the straight groove is matched with a linear protrusion in the first positioning block. A movable block is fixedly arranged at the other end of the reciprocating impact rod, one side of the movable block is attached to the inner wall of a groove in the end drill rod, and the other side of the movable block is attached to an annular double-arrow-shaped groove formed in the rotation transmission rod. The rotation transmission rod is axially limited through a second positioning block arranged on the rotation transmission rod in a sleeving mode. One end of the spiral drill rod is connected with the end drill rod, and a universal coupling is movably arranged in the spiral drill rod; the other end of the rotary transmission rod is connected with one end of a universal coupling, and one end of the universal coupling is detachably connected with a tail connector through the tail end of a spiral drill rod.

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 belongs to the field of coal mine rock burst and gas control, and relates to a high-gas coal seam mining method with cooperation of hydraulic fracturing pressure relief and high drainage roadway, which comprises the following steps: constructing a trend high drainage roadway, and constructing a hydraulic fracturing drill hole and fracturing in an air return crossheading; constructing layer-crossing drilling holes from the trend high drainage roadway to the air return crossheading; tunneling an air return crossheading and ventilating; performing hydraulic fracturing drilling and fracturing in the open-off cut; constructing a layer-penetrating hole from the end part of the trend high drainage roadway to the open-off cut; tunneling a cut hole and ventilating; the air return crossheading is connected with the air return main roadway; bedding drilling and fracturing are carried out in self-air-return crossheading construction; and hydraulic fracturing drilling and fracturing are conducted on the transportation crossheading, the transportation crossheading is tunneled and ventilated, and working face stoping is conducted. Pressure relief is carried out before roadway tunneling, a smooth air flow path can be formed before roadway tunneling and in the tunneling process to extract gas, newly generated gas on a tunnel face can be rapidly extracted, gas extraction can be continuously carried out during stoping, and safety of the whole production process is guaranteed.

The invention relates to the technical field of gas control, and discloses a thick coal seam cross-cut coal uncovering gas control and support control method and system. The method comprises the following steps: acquiring an outburst risk assessment index and a drilling scheme through coal seam parameter data analysis; recording grouting pipeline information and monitoring a grouting process to form a quality data set; constructing a support load diagram to determine temporary support parameters; performing matching analysis to determine permanent support parameters to generate a stress map; analyzing the gas gradient of the key point to determine extraction parameters; and performing correlation analysis and identification on the top plate sinking characteristics and the gas abnormal mode to form safety decision data. According to the method, time sequence correlation analysis is performed on the gas dynamic response characteristics and the support-surrounding rock interaction state, and the mapping relation between the roof sinking critical characteristics and the gas concentration abnormal mode is identified, so that the safety and controllability of the rock cross-cut coal uncovering operation of the thick coal seam are improved.

The invention discloses an electric field fracturing coal seam anti-reflection gas extraction method, and belongs to the field of coal seam gas extraction. S2, generating a three-dimensional geologic model; s3, performing electric field fracturing simulation until an optimal fracturing path is obtained, and taking an electric field parameter corresponding to the optimal fracturing path as an electric field initial parameter; s4, based on the generated three-dimensional coal seam image, a distributed stress sensor, a strain sensor and a displacement sensor are arranged in the fracturing area so as to monitor stress concentration factors, strain and crack length and width changes in the coal seam; s5, applying an electric field initial parameter to the coal seam, and dynamically adjusting the electric field parameter to ensure that an optimal fracturing path is achieved; and S6, gas extraction. By the adoption of the electric field fracturing coal seam anti-reflection gas extraction method, the electric field parameters are dynamically adjusted based on real-time monitoring data, it is ensured that fracturing is conducted along the optimal path all the time, and unnecessary resource waste and potential safety hazards are avoided.

According to the soft low-permeability coal seam hole protecting and permeability increasing integrated pipeline and the using method, a plurality of drill hole protecting and permeability increasing structures are all located in the deep position of a drill hole, hole sealing treatment is conducted on an extraction pipeline, the passive hole protecting, collapse preventing and supporting effects can be achieved on a gas extraction drill hole, and at the moment, gas extraction work is directly conducted; after the flow of the extracted gas is continuously reduced, the drilling hole is sealed firstly, the interior of the drilling hole is pressurized through free desorption of the gas, then gas is injected into all the annular gas bags through the gas injection pipe, all the annular gas bags are expanded in sequence to extrude the positions with collapsed holes so that the positions can be pressed and expanded, and active hole protection work is achieved; and meanwhile, the annular air bag expands to compress the space in the drill hole, so that the air pressure in the drill hole is increased, then the annular air bag retracts when gas is exhausted, and the cycle is repeated, so that variable-frequency pneumatic shock waves can be formed in the gas extraction drill hole to crack a coal body, and the coal seam gas is displaced to be quickly desorbed into the drill hole after fracturing, so that efficient gas extraction is realized.

The invention provides an underground coal mine air and water pumping switching electro-hydraulic control system and method, the electro-hydraulic control system comprises an air supply control module, a water supply control module, a negative pressure control module and an oil supply module, and the method adopts a remote control system to control the underground coal mine air and water pumping switching electro-hydraulic control system. According to the underground coal mine air and water pumping switching electro-hydraulic control system, air and water pumping electric control rapid opening and closing and rapid switching of different functions are achieved, the automation degree of air and water pumping switching is improved, and the air and water pumping switching time is shortened; and meanwhile, when dangerous working conditions that gas accumulation exceeds the limit due to hole blocking behind the drill hole or carbon monoxide gas appears in the drill hole and the like, rapid and automatic response processing can be achieved. The air and water pumping conversion efficiency is improved, the labor intensity of workers is relieved, and key technical support is provided for coal mine underground automatic drilling whole-process operation.

The invention discloses a long-distance subarea step-by-step fracturing coal seam permeability increasing method and system, and the method comprises the steps: dividing a target coal seam into different subareas, setting a plurality of perforation point locations according to fracturing requirements, and obtaining fracturing construction parameters of the subareas of the target coal seam; according to the fracturing construction parameters, directional perforation fracturing is conducted on the target coal seam through a kilometer directional drilling machine provided with a laser device; the deepest perforation of the target coal seam is sealed through a hole packer, a conductive ion solution is injected into the hole, and secondary single-hole local fracturing is conducted through the liquid-electric effect; and respectively connecting the positive electrode and the negative electrode to the walls of two adjacent perforation holes, and performing three-stage two-hole block fracturing by utilizing an electric crushing effect until the coal seam in the partition is completely fractured. According to the method, three-stage step-by-step fracturing permeability increasing of the target coal seam can be achieved, consumption of water resources and energy loss of high-voltage cables are reduced to a great extent, and the energy utilization rate is increased.

The invention discloses a coal roadway gas extraction and roof cutting method based on directional fracturing, and belongs to the field of coal mine underground gas extraction and surrounding rock control. The method comprises the following steps: firstly, carrying out rock stratum analysis and calculation, constructing a drill hole which is parallel to a coal roadway and has the same length as the coal roadway from an uphill and downhill roadway or a cross-cut, cutting a groove, inducing a coal roadway roof to be fractured, crushing an immediate roof of the coal roadway, cutting off stress conduction of the roof and reducing dynamic load strength through a directional cutting groove in the drill hole, and after a working face is stoped, crushing roof rocks, and the hard top plate normally collapses, and pressure relief is completed. Meanwhile, in the fracturing process, cracks extend into the coal seam from the coal roadway roof, a large number of cracks are generated in the coal seam, occurrence gas in the coal seam is extracted more easily, rapid tunneling of the transportation roadway is achieved, and the gas outburst risk in the roadway tunneling process is reduced. The method not only can improve the surrounding rock condition of the roadway and effectively reduce the gob-side entry retaining maintenance cost, but also can improve the gas extraction efficiency and reduce the roadway tunneling risk, and is of great significance to coal mine safety production.

The invention discloses a method for fracturing a low-permeability coal seam by linkage of CO2 and high-pressure water, which comprises the following steps of: performing hydraulic fracturing to form a part of fractures, forming a weak acid environment by utilizing the characteristic that a CO2 medium is easily dissolved in high-pressure water in a high-pressure environment, and promoting chemical reaction between acid water and mineral components on the surfaces of the fractures under the driving of concentration gradient and high-pressure injection, the fractures are pressed by high-pressure water at the same time, so that cooperative work of high-pressure fracturing and CO2 acidification anti-reflection is achieved, and a complex fracture network is formed in the coal seam; after permeability increasing, the pressure is relieved, the normal pressure environment is recovered, at the moment, CO2 media dissolved in the high-pressure water in the layer penetrating drill holes are partially recovered to be in the gas state, CO2 gas and gas can form competitive adsorption in the coal seam, a large amount of gas is displaced and desorbed from the interior of the coal seam, in the whole process, the permeability increasing effect on the coal seam can be effectively achieved, and the coal seam permeability increasing effect is achieved. And no extra damage is caused to the coal seam, finally, on the premise that more energy is not consumed, effective transformation of the pore structure volume of the coal body is achieved to the maximum extent, and the gas extraction efficiency is improved.

The utility model discloses an underground drilling and caving device, which comprises a vertically arranged columnar main body seat and an expansion wing arranged on the columnar main body seat, the main body seat comprises a cylindrical body, the expansion wing comprises a telescopic rod vertically arranged in the body, the upper end of the telescopic rod is vertically and elastically connected with the body, and the lower end of the telescopic rod is connected with a push block; an installation opening is formed in the outer wall, corresponding to the push block, of the lower portion of the body, the expansion wing further comprises a blade wing hinged to the interior of the installation opening, and the blade wing is arranged to be capable of being unfolded outwards under the pushing effect of the push block. By means of the mechanical cave-making method, the cave-making strength can be enhanced, a coal wall can be effectively cut when the coal seam hardness is large, the size of a cave-expanding space can be fixed by stabilizing water pressure, the cave-expanding space can be quantized through the blade unfolding radius, the operation efficiency and accuracy are improved, the operation risk is reduced, and drilling and cave-expanding are stable and reliable; operation faults and safety risks are reduced, and safety and quality of gas drainage operation are improved.

The invention discloses a laser-electric pulse-water jet synergistic fluidized coal mining device and method, and the device comprises a gas extraction system which is used for extracting gas in the coal mining process; the laser perforation system is used for perforating the coal seam through a laser; the high-voltage electric pulse fracturing system is used for fracturing the to-be-fractured coal body between two adjacent perforations through high-voltage electric pulses to obtain a crushed coal body and a to-be-crushed coal body; the water jet coal breaking system is used for performing hydraulic cutting on the to-be-broken coal body to obtain a coal-rock mixture; the fluidization coal mining system is used for conveying the coal and rock mixture into the ground sedimentation tank to complete coal mining; and the backfilling system is used for backfilling the goaf with the gangue mixed mortar separated in the sedimentation tank. The coal mining technology under the synergistic effect of laser, electric pulse and water jet is adopted, accurate drilling and efficient crushing of a coal seam can be achieved, waste of water resources is reduced, and the coal mining efficiency is remarkably improved.

The invention relates to the technical field of tunnel construction, in particular to an integrated monitoring and early warning method and equipment for a tunnel excavation face, the equipment integrates at least a laser radar, a camera, at least one gas sensor, a processor and other electronic components, and three-dimensional point cloud data of the tunnel excavation face are collected through the laser radar; early warning is carried out on surrounding rock disasters of the tunnel excavation face; real-time image data of a tunnel excavation face are collected through a camera and are submitted to a deep learning model to carry out flowing water area identification so as to carry out early warning of mud burst and water burst disasters; at least one gas sensor is arranged to detect concentration values of different types of gases in a tunnel where a tunnel excavation face is located so as to carry out gas disaster early warning; according to the scheme, multiple functions are integrated, surrounding rock disaster early warning, mud burst and water burst disaster early warning and gas disaster early warning can be achieved through one device, higher intelligence and convenience are achieved, and the operation risk of site construction personnel is effectively reduced.

The invention discloses an outburst coal seam crossing drilling pipe-pushing type hydraulic cave-making and spray-eliminating drilling tool which comprises a pipe-planting drill bit, a pipe-pushing and spray-eliminating device, a pipe-pushing jet device, at least one pipe-pushing drill rod and a pipe-pushing hollow water braid which are connected in sequence. A flow supply channel flowing towards the pipe planting drill bit and an exhaust pipe planting channel with the flow direction opposite to that of the flow supply channel are arranged in the pipe planting drill bit, the pipe pushing spray eliminating device, the pipe pushing jet device, the pipe pushing drill rod and the pipe pushing hollow water braid. The hydraulic drilling machine has the beneficial effects that the mode of controlling axial flow supply of a drill bit and radial flow supply of a nozzle through water pressure of a pump is abandoned, switching between axial flow supply and radial flow supply is achieved through an oil pump of the hydraulic drilling machine and a hollow oil cylinder of a hollow water braid of a push pipe, and the hydraulic drilling machine is not affected by the water pressure, the drilling depth and the gas-water pressure in a loose hole gas pocket; radial cave forming can be achieved through water pressure of a clear water pump station, radial cave forming can be achieved through hydrostatic pressure if a soft outburst coal seam occurs, and accurate switching can be achieved.

The invention discloses a system and method for cracking a coal rock stratum through liquid nitrogen and water jet circulation impact. The system comprises a water jet impact system, a liquid nitrogen impact system and a pressure detection system, the main acting object of the system is coal rock stratum drilling, and coal rock is destroyed through low-temperature liquid nitrogen fracturing and water jet strong erosion. In the water jet impact drilling process, residues in a drilled hole can be brought out, a coal body is eroded, a crushing pit is formed, cross cracks are formed around the crushing pit, and a gas migration channel is reconstructed. The cold impact and thermal impact of the low-temperature liquid nitrogen can effectively improve the pore and fracture structure of the coal body, promote the development of cracks formed by water jet impact, and influence the permeability of the coal rock layer. And the water and the ice cyclically impact and supplement each other, so that water in pores is subjected to'water-ice 'two-phase transformation, the damage condition of the coal seam is further enhanced, the pores and cracks in the coal seam are extended, and the situation that' 1 + 1 > 2 'occurs.

The invention provides a coal mine ventilation air methane synergistic enrichment and fluidized heat storage combustion system and method. The system comprises an air shaft diffusion tower and a ventilation air methane collecting device, the method comprises the following steps: collection and compression of ventilation air methane, cooling and boosting adsorption of an adsorption tower, pressure drop equalization of the adsorption tower, temperature rise, pressure reduction and desorption of the adsorption tower, pressure rise equalization of the adsorption tower, periodic cycle work of the adsorption tower, preheating of a packed bed of a heat storage furnace, fluidized heat storage oxidation of coal gangue and gas, and waste heat recovery and utilization. According to the invention, safe and efficient enrichment of ventilation air methane can be realized, and fluidized heat storage oxidation coupling utilization of concentrated gas and coal gangue particles can be realized; the oxidation waste heat is used as a generator heat source; the carbon reduction scheme of large-scale separation and concentration-synergistic oxidation-efficient utilization of the oversize coal mine ventilation air methane is formed, the coal industry is assisted to achieve the goal of'two wastes' and sustainable development, and large-flow, low-cost, safe and efficient treatment and utilization of the ventilation air methane discharged by an oversize low-gas mine can be 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 relates to the technical field of coal mine drilling blowout prevention, in particular to a gas extraction blowout prevention device for coal mine drilling, which comprises a fixed pipe provided with a discharge port and an extraction port, and the discharge port and the extraction port are respectively communicated with external extraction equipment; the stabilizing frame is fixed at the upper end of the fixing pipe; the pressure relief seat is fixed on the fixed pipe, and a pressure relief bin with cooling liquid is formed in the pressure relief seat; the sealing bag body is fixed at one end, far away from the pressure relief seat, of the fixed pipe; the blowout prevention assembly is arranged in the fixing pipe and the pressure relief seat in a sliding mode, and a drill rod is arranged in the blowout prevention assembly in a sliding mode; when drilling work is conducted on a coal mine, coal dust and cooling liquid can be collected through the blowout prevention assembly, leakage is avoided, when gas and coal dust are sprayed out due to damage of the balance state of the coal mine, secondary buffering and pressure relief can be conducted on sprayed-out airflow, and damage of the gas and coal dust to the device is avoided.

The invention provides a well position deployment construction method for a fractured horizontal well considering mine pressure treatment and gas extraction. The well position deployment construction method comprises the steps that firstly, a target key layer is determined; secondly, a ground L-shaped horizontal well is constructed; thirdly, hydraulic staged fracturing is conducted; step 4, reinjection; step 5, filling; sixthly, gas is extracted in a high extraction roadway; and 7, high-position drilling gas extraction is carried out. The method has the advantages of being controllable in drilling track, wide in influence area, low in construction cost and the like, rock burst can be effectively prevented and controlled, the problem that gas in a mining area and a goaf exceeds the limit is solved, meanwhile, the roadway tunneling work amount is reduced, and the purposes of reducing cost and improving efficiency are achieved. According to the method, multiple purposes are achieved through one well, treatment of the rock burst area of the deep coal seam is achieved, the gas extraction effect of a mining area in stoping and the gas extraction effect of a goaf after stoping are improved, and safe production of a mine is guaranteed.