Please select the most similar patent number from A, B, C and D. Which number is?
A vertical ventilation method and system suitable for coal and gas outburst mining using a 110 mining method. The vertical ventilation method comprises: before working face mining, construct a first process roadway (8) and/or a second process roadway (9); during working face mining, the part of a working face track gateway (5) located in a goaf forms a first roof-cut retained roadway section (11) and/or the part of a working face transportation gateway (4) forms a second roof-cut retained roadway section (12) such that intake air of the first roof-cut retained roadway section (11) enters a gas drainage return air roadway (7) through the first process roadway (8) to form return air, and/or intake air of the second roof-cut retained roadway section (12) enters a gas drainage intake air roadway (6) through the second process roadway (9) to form return air. The vertical ventilation system constructed using the gas drainage intake air roadway (6) and the gas drainage return air roadway (7) can monitor retained roadway sections in real time and eliminate the accumulation of harmful gases in the retained roadway sections while implementing the ventilation of the retained roadway sections.
A: A solid-filling coal mining method with two pre-excavated tunnels for advancing. A mining roadway adopts an arrangement mode that the pre-excavated tunnels are taken as air return and inlet roadways and a gob-side entry retaining roadway is taken as a roadway for transporting filling materials and coal; coal extraction and gob backfilling are carried out by a comprehensive mechanical solid-filling coal mining process; and a coal mining method that a mining sequence is propelled by making a filling coal mining working face be back to the direction of transporting the coal to a mountain in a mining area is used. The pre-excavated tunnels are formed, by tunneling, before the extraction of the working face, and the gob-side entry retaining roadway is formed by optimally designed filling bodies beside the roadway along with the implementation of advancing filling coal mining operation along the working face. The coal mining method is simple in process, technically and completely realizes coal milling without pillars, and achieves high coal resource extraction rate. The coal mining method can not only solve the technical problems that a draw-back-type down-mining and up-filling working face cannot ensure a filling effect during a filling milling process of a mine with shortage of resources, but also materialize the comprehensive mechanical solid-filling coal mining of mines with limited geological conditions by virtue of an advancing up-milling and down-filling working face.
B: A complete non-coal-pillar continuous depressurized mining method for a short-distance coal seam group, which is applicable to a coal mining project. The method comprises: determining the mining sequence of coal seams in a coal seam group; when a first coalface (1) of a first mined coal seam is mined, building a filling-wall (11) in which a breather pipe (10) is disposed along the edge of a goaf, so as to form a gob-side entry retaining (12); taking the roadway as a transportation roadway (4) when a second coalface (2) is mined, continuing to perform a gob-side entry retaining (12) in a track roadway, cutting and removing a flexible mold bag (13) on the surface of the previous gob-side entry retaining (12) behind the coalface; and when the coal recovery of the second coalface is completed, filling carbon dioxide into the breather pipe (10) in the filling-wall (11) of the first coalface, so that a carbonization reaction occurs on the filling-wall (11), and the filling-wall (11) is broken and decomposed. After the mining of a coal seam is completed, because a top plate is not supported by a coal-rock pillar, the top plate can move and sink fully and the depressurized mining on adjacent coal seams can be achieved, thereby avoiding the stress concentration produced by the hangover of the filling-wall, and facilitating the mining space maintenance, gas extraction and dynamic disaster prevention and control.
C: A test method for simulating spontaneous combustion in a goaf region, employing a test device simulating spontaneous combustion in a goaf region. A test furnace of the test device is provided with a coal outlet (6), an air inlet pipe (19), and an air return pipe (20). The test furnace is provided therein with a coal seam (8), a similar material base plate (9), a preconfigured water bag (10), a similar material base plate (11) to be sunk, a first similar material top plate (12), and a second similar material top plate (13). Multi-point thermocouple measurement rods (15) and gas collection tubes (17) are provided on the second similar material top plate (13). A coating layer (14) is provided between the multi-point thermocouple measurement rods (15). The multi-point thermocouple measurement rods (15) are provided with several thermocouples (16). The multi-point thermocouple measurement rods (15) and the gas collection tubes (17) are in close contact with the similar material. Two ends of a coal face (21) on the coal seam (8) are provided with an intake airway (32) and a ventilation airway (33). An arc-shaped perforated protection tube (18) is laid at the intake airway (32), the coal face (21), and the ventilation airway (33) to support coal and form a certain channel space, so as to construct an air intake and ventilation system for a goaf region and the face. The test method enables accurate and effective simulation of the entire process of spontaneous combustion in a goaf region under air leakage conditions.
D: A staged ventilation method based on the construction of a complex cavern group, comprising the following steps: perform press-in ventilation while digging in inclined shaft channels, and air supply stopping points reach the entrance of a third sub-channel (6) and the exit of a fourth sub-channel (7); S2: the air supply stopping points reach the entrance of a second sub-channel (5), the exit of a seventh sub-channel (10), and the exit of a triple arch section (2) close to the fourth sub-channel (7); S3: the air supply stopping point of the ath inclined shaft channel (11) directly reaches a tunnel section (1) at a corresponding end, and further reaches the triple arch section (2) and the tunnel section (1) at the corresponding end through the second sub-channel (5) and a sixth sub-channel (9), and the air supply stopping point of the bth inclined shaft channel (12) reaches the tunnel section (1) at a corresponding end and the triple arch section (2) through the seventh sub-channel (10) and the fourth sub-channel (7); S4: form a tunnel-type full-air-pressure ventilation system of a main through air flow tunnel; S5: continue to perform full-air-pressure ventilation while digging; and S6: combine the full-air-pressure ventilation while digging and exhaust ventilation while digging. The method has the advantages of ensuring a construction period, improving construction quality and construction safety, satisfying the ventilation requirement of construction work in all stages, and saving energy and reducing consumption.
Answer: D