Abstract: A coal rock interface directional detection device based on elastic waves includes: a probe body including an elastic wave receiving device and an elastic wave excitation device spaced set at the top; a protective tube with one end connected to the adapter. The protective tube includes a collection circuit board inside the protective tube, and the collection circuit board is electrically connected to the elastic wave receiving device and the elastic wave excitation device; a sleeve, installed outside the protective tube, with one end connected to the side of the probe body near the adapter and with the other end connected to the side of the protective tube away from the adapter; and a control host, wirelessly connected with the acquisition circuit board. A coal rock interface directional detection method based on elastic waves applied in the coal rock interface directional detection device is also disclosed.

Abstract: Disclosed are an integrated mining method and an integrated mining system of coal breaking, coal extraction and water circulation in a U-well. The integrated mining system includes a first ground facility unit, a second ground facility unit, a jet unit and an extraction unit. The first ground facility unit is configured to transport jet fluid to the jet unit. The jet unit is configured to break a coal seam in a sub-segment to obtain broken cinders. The extraction unit is configured to extract a coal-water mixture. The second ground facility unit is configured to receive the coal-water mixture. In response to determining that an extraction of the sub-segment is complete, the jet unit and the extraction unit is configured to move to a next sub-segment using powers provided by the first ground facility unit and the second ground facility unit.

Abstract: A coal and coalbed methane mining system based on ground drilling includes: a drilling component, a coal mining drill bit and a ground facility group. The coal mining drill bit is set at a predetermined end of a directional borehole in a coal seam, connected to the drilling component through a connecting pipeline. The ground facility group is connected to the drilling component, to provide coal cutting slurry for the coal mining drill bit, receive reflux slurry carrying coal and coalbed methane, and precipitate and separate the reflux slurry carrying the coal and the coalbed methane. A coal and coalbed methane mining method based on ground drilling and related devices are also disclosed.

Abstract: Disclosed is a grouting and water blocking method for a hard rock stratum. The grouting and water blocking method include the following steps. At first, hydrogeological information and coal seam information of a hard rock stratum is obtained. Then, a drilling trajectory of the hard rock stratum is determined based on the hydrogeological information and the coal seam information. Later, at least one drilling device is determined corresponding to the drilling trajectory based on types of multiple rock layers contained in the hard rock stratum. After that, the multiple rock layers contained in the hard rock stratum are drilled sequentially according to the drilling trajectory using the at least one drilling device. At last, in response to determining there is a water leakage area, the water leakage area is grouted.

Abstract: A directional drilling method applied to a rigid bending joint directional drilling device includes: obtaining geological data; determining a lateral drilling point and a target point of a branching borehole based on the geological data; drawing a target borehole trajectory of the branching borehole based on the lateral drilling point and the target point; obtaining parameters of the drill pipe; determining a propulsion force corresponding to the target borehole trajectory based on the parameters, the target borehole trajectory, and the geological data; and applying the propulsion force to the rigid bending joint directional drilling device for drilling the branching borehole. A directional drilling system and related devices are also disclosed.

Abstract: Disclosed is a method for repairing an aquifer in a coal mine area by grouting, including: drilling a survey hole in a ground area corresponding to a water inflow position from ground surface to a caving zone in a goaf; determining a target layer for grouting in the survey hole based on drilling data collected from the survey hole while drilling; changing the survey hole to a grouting hole; measuring a first water level from the grouting hole; grouting through the grouting hole; changing the grouting hole to an observation hole; measuring a second water level from the observation hole; and determining a water retention level based on the first water level and the second water level.

Abstract: Disclosed are a method and a related device for determining a development status of a separation layer in a coal mine. The method includes: obtaining surface subsidence variation data of the coal mine within a preset time interval, rock stress variation data of a caving zone of the coal mine and water pressure variation data; determining a height decrease of the caving zone based on the rock stress variation data and the water pressure variation data; and determining the development status of the separation layer of the coal mine based on the height decrease and the surface subsidence variation data.

Abstract: A tracer diffusion device includes: a first container, a second container, a drilling pipe, a unidirectional driving device, and a bidirectional driving device. The first container holds a first fluid containing a tracer. The second container holds a second fluid. A first end of the drilling pipe is connected to the first container; a second end of the drilling pipe is extended into a borehole and equipped with a first sealing capsule and a second sealing capsule. A plurality of through holes are arranged on the drilling pipe between the first sealing capsule and the second sealing capsule. The unidirectional driving device is arranged on the drilling pipe, for injecting the first fluid from the first container into the borehole between the first sealing capsule and the second sealing capsule. The bidirectional driving device is arranged between the second container and the first sealing capsule.

Abstract: A curvature controllable directional drilling device is disclosed. The drilling device includes: a drill bit, a power unit, a rigid bending unit, a bendable outer wall, and a wedge deflection tool. The power unit is to provide a rotary power to the drill bit. The rigid bending unit is set between the drill bit and the power unit, to bend on a basis of an initial curvature under an external force. The bendable outer wall is set on an outer side of the power unit and the rigid bending unit. The wedge deflection tool is set at one end of the bendable outer wall near the drill bit, to receive a reaction force and bend the rigid bending unit. By a coordination between the wedge deflection tool and the power unit, a drilling direction of the drill bit connected to the rigid bending unit can be adjusted.

Abstract: A tracer diffusion device includes: a first container, for holding a first fluid containing a tracer; a second container, for holding a second fluid; a drilling pipe; wherein, a first end of the drilling pipe is connected to the first container; a second end of the drilling pipe is extended into a borehole; and the second end of the drilling pipe is equipped with a first sealing capsule and a second sealing capsule; a plurality of through holes are arranged on the drilling pipe between the first sealing capsule and the second sealing capsule; a unidirectional driving device, arranged on the drilling pipe, for injecting the first fluid from the first container into the borehole between the first sealing capsule and the second sealing capsule; and a bidirectional driving device, arranged between the second container and the first sealing capsule.

Abstract: Disclosed is a system and a method of transient electromagnetic advanced detection. The system includes a detection host, an electromagnetic signal transmitter, a probe, and a communication device. The system and method of transient electromagnetic advance detection disclosed by examples of the present disclosure can realize an early-warning through a transient electromagnetic advance detection in a borehole while drilling the borehole in a tunnel or a roadway.

Abstract: A method for blocking mine water inrush includes: grouting first slurry into an interface between the quaternary aquifer and the weathered bedrock aquifer in a fracture grouting manner until a first preset condition is met; forming a first water-resisting cushion after the first slurry is solidified; drilling a curve branch drill hole in the surface horizon downward; grouting second slurry into the curve branch drill hole in a downward grouting manner until a second preset condition is met; forming a second water-resisting cushion after the second slurry is solidified; grouting third slurry onto a top of the first water-resisting cushion in an upward grouting manner until a third preset condition is met; forming a third water-resisting cushion after the third slurry is solidified; wherein the third water-resisting cushion is located on the top of the first water-resisting cushion.

Abstract: The present disclosure discloses a method for strengthening a biological manganese oxidation using a magnetic field and use thereof. The method includes steps of inoculating a manganese-oxidizing microorganism into a culture medium containing Mn2+, performing magnetization treatment in a culture process, and then collecting a biogenic manganese oxide. The method includes steps of performing a primary magnetic field treatment at a magnetic field intensity of 0.2-50 mT for 1-5 h when culturing is performed for 6-12 h, continuing culturing after the primary magnetization treatment, and performing magnetization treatment once every other 24 h for culture time of 72 h. A magnetic field is applied to accelerate an oxidation rate of a manganese-oxidizing microorganism to Mn2+and a biological manganese oxidation rate is respectively improved by 36.4% and 23.8% under an action of an alternating magnetic field or a constant magnetic field within 72 h.

Abstract: A sealing method for a drilled hole in three zones of overburden comprises: blocking the fissure zone and the caving zone with at least one filling bag; and transporting prepared cement slurry to the drilled hole through a hollow drill pipe, so as to block the curved subsidence zone. The three zones of overburden comprise a fissure zone, a caving zone and a curved subsidence zone.

Abstract: Disclosed is a system and a method of transient electromagnetic advanced detection. The system includes a detection host, an electromagnetic signal transmitter, a probe, and a communication device. The system and method of transient electromagnetic advance detection disclosed by examples of the present disclosure can realize an early-warning through a transient electromagnetic advance detection in a borehole while drilling the borehole in a tunnel or a roadway.

Abstract: Disclosed is a system and a method for monitoring water inrush, including: a host terminal, a field host, at least one controller and at least one electrode array. Each electrode array is placed in one borehole and to detect electric field signals of surrounding rocks around the borehole; each controller connects with one electrode array and is to control the electrode array to carry out a high-density induced polarization measurement on the surrounding rocks; the field host connects with the controller and is to send control signals to the controller, receive and process the electric field signals output by the electrode array; and the host terminal connects with the field host and is to receive the electric field signals processed by the field host, determine changes on apparent resistivity and apparent chargeability of the surrounding rocks, and determine whether there exists water inrush according to the changes.

Abstract: A bidirectional variable cross-section water-pressure bearer cycle test system for a coal mine water inrush model test, comprising a water-pressure loading portion and a water-pressure bearer portion, wherein the water-pressure loading portion has a water supply tank, a loading water pump, a water piezometer, a water control valve, a water inlet pipe, a water discharge pipe, etc., through the loaded water pressure to control the cyclic loading of the water pressure. The water-pressure bearer portion has a variable cross-section water-pressure bearer assembly and a airtight main frame variable water-level water-pressure bearer assembly.

Abstract: Disclosed is a system and a method for monitoring water inrush, including: a host terminal, a field host, at least one controller and at least one electrode array. Each electrode array is placed in one borehole and to detect electric field signals of surrounding rocks around the borehole; each controller connects with one electrode array and is to control the electrode array to carry out a high-density induced polarization measurement on the surrounding rocks; the field host connects with the controller and is to send control signals to the controller, receive and process the electric field signals output by the electrode array; and the host terminal connects with the field host and is to receive the electric field signals processed by the field host, determine changes on apparent resistivity and apparent chargeability of the surrounding rocks, and determine whether there exists water inrush according to the changes.

Abstract: Disclosed is a three-dimensional directional transient electromagnetic advanced detection device, wherein the CPU and the bus communication end of the transient electromagnetic transmitting module are both connected to the system bus, the signal output end of the transient electromagnetic transmitting module is connected to the transient electromagnetic transmitting coil outside the borehole to be detected, the signal input end of the electromagnetic signal receiving module is connected to the signal output ends of the three-dimensional magnetic field sensor and the one-dimensional Z-directional electric field sensor, the signal output end of the electromagnetic signal receiving module is connected to the electromagnetic signal input end of the SCM, the communication end of the first memory is connected to the data storage end of the SCM, the communication end of the three-dimensional electronic compass is connected to the compass signal communication end of the SCM, the host data communication of the SCM is

Abstract: Disclosed is a three-dimensional digital virtual imaging device for stratigraphic texture of borehole core, wherein the probe depth counting pulley is mounted on the lifting wire frame, the output shaft of the motor is configured to drive the reel to rotate, and one end of the cable is connected to the cable transfer node of the retractable reel, the signal input end of the borehole imaging trajectory measuring probe of the on-site imaging host is electrically connected to one end of the cable through the cable transfer node of the retractable reel, the cable is wound on the retractable reel, a retractable line is controlled by the retractable reel, the cable is extended and retracted on the probe depth counting pulley, the probe depth counting pulley records the length of the retractable line of the cable, the depth feedback signal output end of the depth counting pulley is connected to the depth feedback signal input end of the on-site imaging host, the motor control signal output end of the on-site imaging