Oil-rich coal in-situ pyrolysis development layout and semi-coke complete filling mining system and method

Abstract

The invention discloses an oil-rich coal in-situ pyrolysis development layout and semi-coke complete filling mining system and method, which are characterized in that oil-rich coal in-situ pyrolysis mining area optimization, pyrolysis reaction area arrangement, in-situ heat injection pyrolysis reaction, pyrolysis semi-coke resource mining and goaf complete filling are carried out to realize oil-rich coal in-situ depolymerization generation and coal tar and coal gas extraction; semi-coke resource mining, complete strip filling and unmanned intelligent continuous mining equipment are divided, and coal-based solid waste materials and a goaf filling system are utilized to realize semi-coke resource intelligent mining and goaf complete filling. According to the method, the environmental problems of surface subsidence, underground water damage and the like are greatly reduced, and meanwhile mining area solid waste resource utilization and low-carbon treatment are completed. Through the mode of filling after heat injection and extraction pipelines are arranged, the thermal insulation effect and the transportation efficiency of the pyrolysis oil and gas collection pipeline are improved. The intelligent mining operation of complete filling of the pyrolysis semi-coke resources is carried out in a mining-filling parallel mode, and the effects of continuous mining and continuous filling and full mining and full filling are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of coal mining, and in particular to an in-situ pyrolysis development layout of oil-rich coal and a semi-coke resource full-filling mining system and method. Background Art

[0002] Coal is my country's basic energy and important industrial raw material. At present and for a long time to come, the dominant position and ballast role of coal resources in my country's energy system will not change. Therefore, promoting the energy revolution and accelerating the clean and efficient use of coal are the inevitable choices to support my country's green and low-carbon energy transformation, ensure national energy security and achieve the "dual carbon" goal.

[0003] Oil-rich coal is a coal-based oil and gas resource. The tar and coal gas (10% to 30%) can be extracted from the oil-rich coal by medium-low temperature pyrolysis under air-tight conditions, generating semi-coke (about 70%) resources that can replace anthracite and coking coal. This is an important way to achieve efficient utilization of oil-rich coal in stages. However, compared with shale oil (gas) underground pyrolysis technology, this technology is still in the early exploration stage. Well-type in-situ pyrolysis is one of the most promising development directions for the green and low-carbon development of oil-rich coal.

[0004] However, due to the complexity of the occurrence conditions of oil-rich coal and the multi-phase and multi-field coupling characteristics of the pyrolysis process, the key technical problems that need to be urgently solved in the in-situ pyrolysis and mining of oil-rich coal are the heating methods of the in-situ pyrolysis mining area, the collection of pyrolysis oil and gas, the secondary mining of semi-coke and the control of surrounding rocks. Summary of the invention

[0005] In order to solve the above-mentioned defects existing in the prior art, the purpose of the present invention is to provide an in-situ pyrolysis development layout of oil-rich coal and a semi-coke complete filling mining system and method. Firstly, by optimizing the in-situ mining area of ​​oil-rich coal, causing the in-situ heat injection pyrolysis reaction, and arranging the oil and gas collection system, the in-situ depolymerization of oil-rich coal is realized to generate and extract coal tar and coal gas; then, the in-situ pyrolysis mining area is divided into semi-coke resource mining and complete filling strips, and through unmanned intelligent continuous mining equipment, coal-based solid waste materials and filling systems are used to realize intelligent mining of semi-coke resources and complete filling of goafs, which greatly reduces environmental problems such as surface subsidence and groundwater damage, while completing the resource utilization and low-carbon disposal of solid waste in the mining area.

[0006] The present invention is achieved through the following technical solutions.

[0007] In one aspect of the present invention, there is provided an oil-rich coal in-situ pyrolysis development layout and a semi-coke complete filling mining system, including an above-hole and a below-hole section;

[0008] The above-the-hole part includes: a pyrolysis oil and gas collection system, which is used to transport the coal tar and coal gas generated by in-situ depolymerization of the collected pyrolysis oil-rich coal to the surface oil and gas separation station through the pyrolysis oil and gas collection pipeline;

[0009] The underground part includes:

[0010] The tunnel layout system is used to divide the oil-rich coal in-situ pyrolysis mining area and the pyrolysis semi-coke resource mining area, and to carry out the layout of the in-situ pyrolysis development tunnels for the oil-rich coal;

[0011] The oil-rich coal in-situ pyrolysis mining area is used to separate coal tar and coal gas from the underground oil-rich coal reservoir through the fracture network of the high-temperature steam heating system;

[0012] The high-temperature steam heating system is arranged on the working face of the oil-rich coal in-situ pyrolysis mining area, and is used to pre-crack and generate a fracture network in the oil-rich coal reservoir through a fracturing device, and high-temperature steam is injected into the fracture network of the oil-rich coal reservoir;

[0013] The pyrolysis semi-coke resource mining area is used for intelligent mining of pyrolysis semi-coke resources;

[0014] Insulation system, constructing filling bodies at the working face of the oil-rich coal in-situ pyrolysis mining area, used for drilling and grouting sealing operations on the coal seam roof and floor rock strata;

[0015] The goaf filling system is used to completely fill the goaf formed after the pyrolysis semi-coke resource mining area is mined.

[0016] As a preferred embodiment, the tunnel layout system includes a main shaft, an auxiliary shaft, a ventilation shaft, a main return air shaft, a main transport shaft, an auxiliary transport shaft, a transport horizontal shaft, a return air horizontal shaft and a measure shaft; the main shaft, the auxiliary shaft and the ventilation shaft are excavated from the ground, and the auxiliary shaft and the ventilation shaft are respectively located on both sides of the main shaft; the main return air shaft, the main transport shaft and the auxiliary transport shaft are arranged in parallel and connected with the ventilation shaft, the main shaft and the auxiliary shaft respectively;

[0017] The transport lane and the return air lane are arranged in parallel and located on both sides of the working face of the pyrolysis semi-coke resource mining area and the working face of the oil-rich coal in-situ pyrolysis mining area, and are vertically connected with the main return air lane, the main transport lane and the auxiliary transport lane;

[0018] The measures tunnel is arranged along the working face of the pyrolysis semi-coke resource mining area and the oil-rich coal in-situ pyrolysis mining area, and is connected with the return air tunnel and the transport tunnel respectively, dividing the mining area into strip mining areas.

[0019] Preferably, the high-temperature steam heating system comprises a fracturing device, a high-temperature steam injection pipeline, an underground substation and a high-temperature steam heating device;

[0020] The fracturing device, high-temperature steam heating device and underground substation are located in the transport level tunnel on the working face side of the oil-rich coal in-situ pyrolysis mining area; a number of high-temperature steam injection holes distributed in an array are arranged on the coal wall of the oil-rich coal in-situ pyrolysis mining area, and the boreholes are interconnected through high-temperature steam injection pipelines, and openings corresponding to the high-temperature steam injection holes are distributed on the steam injection pipelines; the high-temperature steam injection pipelines are connected to the high-temperature steam heating device and the fracturing device;

[0021] The underground substation is electrically connected to the fracturing device and the high-temperature steam heating device.

[0022] Preferably, the pyrolysis oil and gas collection system comprises a pyrolysis oil and gas collection pipeline, a pyrolysis oil and gas pipeline secondary heating device, a pyrolysis oil and gas storage and separation station, and a pyrolysis oil and gas collection hole;

[0023] The pyrolysis oil and gas storage and separation station is located on the ground, the pyrolysis oil and gas pipeline secondary heating device is deployed in the return air lane, the pyrolysis oil and gas collection hole is located in the coal wall of the in-situ pyrolysis mining area of ​​the oil-rich coal, the pyrolysis oil and gas pipeline secondary heating device and the pyrolysis oil and gas storage and separation station are connected to the pyrolysis oil and gas collection hole through the pyrolysis oil and gas collection pipeline, and the pyrolysis oil and gas collection pipeline is distributed with openings corresponding to the pyrolysis oil and gas collection hole;

[0024] The pyrolysis oil and gas collection pipelines and the high-temperature steam injection pipelines are staggeredly distributed in the oil-rich coal reservoir in the oil-rich coal in-situ pyrolysis mining area.

[0025] As a preferred option, the pyrolysis semi-coke resource mining area includes mining working strips and unmanned intelligent mining equipment; the unmanned intelligent continuous mining equipment includes an intelligent all-in-one excavator and anchor machine, a crusher, a transfer machine, a wet dust removal fan and a local ventilator.

[0026] Preferably, the goaf filling system includes a gangue-concrete filling slurry preparation station and a grouting pipeline; the filling slurry preparation station is located in the return air level tunnel on the pyrolysis semi-coke resource mining area side, and the filling slurry is transported to the goaf of the pyrolysis semi-coke resource mining area through the grouting pipeline.

[0027] Accordingly, the present invention further provides an oil-rich coal in-situ pyrolysis development layout and semi-coke complete filling mining method of the system, comprising the following steps:

[0028] S1, Optimization of in-situ pyrolysis mining area for oil-rich coal:

[0029] Conduct detailed exploration and evaluation of the coal quality characteristics and geological conditions of oil-rich coal; carry out geological resource evaluation and engineering adaptability evaluation according to different resource occurrences and geological conditions; comprehensively determine the in-situ pyrolysis mining area of ​​oil-rich coal mines based on the evaluation results and the in-situ pyrolysis mining area layout principles;

[0030] S2, pyrolysis reaction zone tunnel layout:

[0031] In the oil-rich coal mine, the in-situ pyrolysis working face is excavated to form a tunnel layout, several pyrolysis reaction zones are divided along the inclination direction of the coal seam, and the measure tunnels are excavated to form a complete tunnel layout system;

[0032] The oil-rich coal in-situ pyrolysis mining area is divided into working strips along the strike through the measure tunnel, and the oil-rich coal reservoir is pre-cracked by the fracturing device to form a fracture network of the oil-rich coal reservoir;

[0033] Drill holes in the coal wall in the tunnel to connect and lay high-temperature steam injection pipelines and pyrolysis oil and gas collection pipelines;

[0034] Construct a filling insulation layer for the working face of the in-situ pyrolysis mining area of ​​oil-rich coal, and construct a grouting water-blocking insulation layer for the roof and floor rock of the coal seam in the pyrolysis reaction area;

[0035] Arrange filling insulation layers on both sides of the coal wall of the working strip of the oil-rich coal in-situ pyrolysis mining area to form several oil-rich coal in-situ pyrolysis mining area strips arranged along the strike direction;

[0036] S3, in-situ heat injection pyrolysis:

[0037] A high-temperature steam heating device and an underground substation are arranged in the transport lane of the working face of the in-situ pyrolysis mining area of ​​the oil-rich coal, and connected with the high-temperature steam injection pipeline to form a high-temperature steam heating system; high-temperature steam is injected into the fracture network of the oil-rich coal reservoir to cause a pyrolysis reaction of the oil-rich coal, and coal tar, coal gas and solid semi-coke are precipitated from the fracture network of the oil-rich coal reservoir; the coal tar and coal gas are transported to the ground pyrolysis oil and gas separation station, and the pyrolysis oil and gas are stored;

[0038] S4, pyrolysis coke resource exploitation:

[0039] After the oil-rich coal is in-situ pyrolyzed, the high-temperature steam heating system and the pyrolysis oil and gas collection system are moved to the next oil-rich coal in-situ pyrolysis mining area, and the in-situ heat injection pyrolysis is repeated;

[0040] The in-situ pyrolysis mining area of ​​oil-rich coal is formed by removing the high-temperature steam heating system and the pyrolysis oil and gas collection system to form a pyrolysis semi-coke resource mining area;

[0041] Remove the insulation layer filled in the coal wall of the transport lane, and exploit the pyrolysis semi-coke resources formed after in-situ pyrolysis in the pyrolysis semi-coke resource mining area;

[0042] Deploy intelligent mining equipment within the mining work strip of the pyrolysis semi-coke resource mining area to carry out unmanned intelligent mining of pyrolysis semi-coke resources;

[0043] S5, goaf is completely filled:

[0044] After the pyrolysis semi-coke resources are mined, the goaf strip is completely filled, and the filling equipment is arranged in the return air level tunnel to transport the filling slurry to the goaf area for complete filling operation;

[0045] Since then, the in-situ pyrolysis development layout of oil-rich coal and the complete filling and mining of semi-coke resources have been completed.

[0046] In step S1, the principle for selecting the in-situ pyrolysis mining area for oil-rich coal is:

[0047] ① The coal quality, thickness and moisture content of the oil-rich coal in the in-situ pyrolysis mining area are stable, and the presence of faults, anticlines and synclines is avoided;

[0048] ② The roof and floor rock layers of the oil-rich coal seam are dense rock layers that meet the requirements of thickness, compressive strength and air tightness, and there are water-proof layers;

[0049] ③Through grouting reinforcement, the oil-rich coal roof and bottom rock strata can be sealed, water-proof, and heat-insulating.

[0050] In step S2, the pyrolysis reaction zone tunnels are arranged to form a complete ventilation system at the working face of the mining area. The ventilation route of the working face is: main shaft, auxiliary shaft → main transport tunnel → auxiliary transport tunnel → transport level tunnel → return air level tunnel → main return air tunnel → air shaft → ground;

[0051] In step S4, during the normal mining period of pyrolysis semi-coke resources, the transportation route is: mining working strip → transfer machine → transportation level tunnel → main transportation tunnel → main shaft → ground;

[0052] The ventilation route is: auxiliary transport tunnel → transport tunnel → mining working strip → return air tunnel → main return air tunnel.

[0053] In step S5, the goaf is completely filled, and the intelligent mining operation of pyrolysis semi-coke resources and the goaf complete filling operation are carried out simultaneously without interfering with each other, including:

[0054] The “interval skipping mining” method is adopted along the mining working strip to carry out intelligent mining of pyrolysis semi-coke in the pyrolysis semi-coke resource mining area (D);

[0055] After the mining of each mining strip is completed, a goaf is formed. The mining equipment is removed and both ends of the goaf are closed. Filling equipment and transportation pipelines are arranged to completely fill the goaf. After the slurry solidifies for a certain period of time, the support strength can be reached, and a dense filling body is formed in the goaf.

[0056] While filling the goaf, pyrolysis semi-coke mining is carried out in the interval strips. The mining and filling operations are carried out in two non-adjacent strips. The semi-coke resource mining and goaf filling operations are continuous in time and space and relatively independent in space.

[0057] After the strip slurry solidifies to form a dense filling body, the semi-coke resources in the pyrolysis reaction zone are completely filled and the intelligent mining work is completed.

[0058] The present invention adopts the above technical solution, which has the following beneficial effects:

[0059] 1) The present invention proposes an in-situ pyrolysis development layout of oil-rich coal and a method for complete filling and mining of semi-coke resources. By optimizing the in-situ mining area of ​​oil-rich coal, causing in-situ heat injection pyrolysis reaction, and arranging an oil and gas collection system, the in-situ depolymerization of oil-rich coal is achieved to generate and extract coal tar and coal gas. Through unmanned intelligent continuous mining equipment, coal-based solid waste materials and a filling system, intelligent mining of semi-coke resources and complete filling of goafs are achieved, and ultimately efficient separate mining of oil-rich coal, oil and gas, and pyrolysis semi-coke resources is achieved. The overall system is simple and the process flow is clear. While significantly reducing environmental problems such as surface subsidence and groundwater damage, the resource utilization and low-carbon disposal of solid waste in the mining area are completed.

[0060] 2) The present invention divides the oil-rich coal pyrolysis mining area into strips by excavating a measure tunnel, which is beneficial to improving the controllable shock wave and hydraulic fracturing effects of the oil-rich coal reservoir. By arranging heat injection and extraction pipelines in the measure tunnel and filling them afterwards, heat loss is greatly reduced, and the insulation effect and transportation efficiency of the pyrolysis oil and gas collection pipeline are improved.

[0061] 3) The present invention adopts a mining-filling parallel mode to carry out intelligent mining operations for complete filling of pyrolysis semi-coke resources. The pyrolysis semi-coke mining operation and the goaf filling operation are carried out in different strips, ensuring the continuity of the mining operation and the filling operation in time and space and the relative independence of space, achieving the effect of continuous mining and filling, and full mining and full filling. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The drawings described herein are used to provide a further understanding of the present invention, constitute a part of the present application, and do not constitute an improper limitation of the present invention. In the drawings:

[0063] Figure 1 It is a schematic diagram of the method of the present invention;

[0064] Figure 2 The method system and process diagram of the present invention;

[0065] Figure 3 This is a cross-sectional view of the arrangement of the pre-splitting drilling holes and the collection drilling holes in the pyrolysis reaction zone of the present invention;

[0066] Figure 4 The present invention is a flow chart of the method.

[0067] In the figure: A, tunnel layout system; A-1, main shaft; A-2, auxiliary shaft; A-3, air shaft; A-4, main return air lane; A-5, main transport lane; A-6, auxiliary transport lane; A-7, transport level lane; A-8, return air level lane; A-9, measure lane;

[0068] B. High-temperature steam heating system; B-1. Fracturing device; B-2. High-temperature steam injection hole (pre-fracture drilling hole); B-3. High-temperature steam injection pipeline; B-4. Underground substation; B-5. High-temperature steam heating device;

[0069] C. Pyrolysis oil and gas collection system; C-1. Pyrolysis oil and gas collection pipeline; C-2. Pyrolysis oil and gas pipeline secondary heating device; C-3. Pyrolysis oil and gas storage and separation station; C-4. Pyrolysis oil and gas collection hole;

[0070] D. Pyrolysis semi-coke mining system; D-1~D-6-mining working strips;

[0071] E. In-situ pyrolysis mining area of ​​oil-rich coal;

[0072] F, thermal insulation layer; F-1-filling insulation layer; F-2-grouting water-blocking insulation layer.

[0073] G. Goaf filling system; G-1- Gangue-concrete filling slurry preparation station; G-2- Grouting pipeline. DETAILED DESCRIPTION

[0074] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. The exemplary embodiments and descriptions of the present invention are used to explain the present invention but are not intended to limit the present invention.

[0075] like Figure 1 , Figure 2 As shown, the present invention provides an oil-rich coal in-situ pyrolysis development layout and semi-coke complete filling mining system, including two parts, the above-ground part includes a pyrolysis oil and gas collection system C; the underground part includes a tunnel layout system A, a high-temperature steam heating system B, a pyrolysis semi-coke resource mining area D, an oil-rich coal in-situ pyrolysis mining area E, an insulation system F and a goaf filling system G.

[0076] Among them, the tunnel layout system A is excavated to form a standard underground tunnel layout, which is used to divide the oil-rich coal in-situ pyrolysis mining area E and the pyrolysis semi-coke resource mining area D, that is, to divide the oil-rich coal in-situ pyrolysis working face and the semi-coke resource mining working face: including main shaft A-1, auxiliary shaft A-2, air shaft A-3, main return air tunnel A-4, main transport tunnel A-5, auxiliary transport tunnel A-6, transport level tunnel A-7, return air level tunnel A-8 and measure tunnel A-9.

[0077] like Figure 1 , Figure 2As shown, the main shaft A-1, auxiliary shaft A-2 and ventilation shaft A-3 are excavated from the ground. The auxiliary shaft A-2 and ventilation shaft A-3 are located on both sides of the main shaft A-1 respectively. The main return air lane A-4, the main transport lane A-5 and the auxiliary transport lane A-6 are arranged in parallel and connected with the ventilation shaft A-3, the main shaft A-1 and the auxiliary shaft A-2 respectively; that is, the main return air lane A-4 is connected with the ventilation shaft A-3, the main transport lane A-5 is connected with the main shaft A-1, and the auxiliary transport lane A-6 is connected with the auxiliary shaft A-2. It is connected and penetrated with the auxiliary shaft A-2; the transport tunnel A-7 and the return air tunnel A-8 are arranged in parallel and located on both sides of the working faces of the pyrolysis semi-coke resource mining area D and the oil-rich coal in-situ pyrolysis mining area E, and are vertically connected with the main return air tunnel A-4, the main transport tunnel A-5 and the auxiliary transport tunnel A-6 along the working face direction; the measure tunnel A-9 is located between the working strips of the pyrolysis semi-coke resource mining area D, with a width of 3 to 5m, and the two ends of the tunnel are connected with the return air tunnel A-8 and the transport tunnel A-7 respectively.

[0078] The high-temperature steam heating system B is arranged on the working face of the oil-rich coal in-situ pyrolysis mining area E, and is used to generate high-temperature steam, which is injected into the fracture network of the oil-rich coal reservoir, and stimulates the pyrolysis reaction of the oil-rich coal through heat transfer between the heat-carrying fluid and the coal body. It includes a fracturing device B-1, a high-temperature steam injection pipeline B-3, an underground substation B-4, and a high-temperature steam heating device B-5.

[0079] like Figure 2 As shown, the fracturing device B-1, the high-temperature steam heating device B-5 and the underground substation B-4 are located in the transport level tunnel A-7 of the working face of the oil-rich coal in-situ pyrolysis mining area E. A number of high-temperature steam injection holes B-2 are arranged in an array on the coal wall of the oil-rich coal in-situ pyrolysis mining area E. The horizontal spacing of the boreholes is 1 to 2 meters. Each borehole is interconnected with the high-temperature steam injection pipeline B-3. The steam injection pipeline B-3 is distributed with openings corresponding to the high-temperature steam injection holes B-2; the high-temperature steam injection pipeline B-3 is connected to the high-temperature steam heating device B-5 and the fracturing device B-1. The underground substation B-4 provides the required power to the fracturing device B-1 and the high-temperature steam heating device B-5.

[0080] The pyrolysis oil and gas collection system C includes a pyrolysis oil and gas collection pipeline C-1, a pyrolysis oil and gas pipeline secondary heating device C-2 and a pyrolysis oil and gas storage and separation station C-3.

[0081] like Figure 2 Combination Figure 3As shown, the pyrolysis oil and gas storage and separation station C-3 is located on the ground, the pyrolysis oil and gas pipeline secondary heating device C-2 is deployed in the return air level tunnel A-8, and a number of pyrolysis oil and gas collection holes C-4 distributed in an array are arranged in the coal wall of the oil-rich coal in-situ pyrolysis mining area E, and the horizontal spacing of the boreholes is 1 to 2m; the pyrolysis oil and gas pipeline secondary heating device C-2 and the pyrolysis oil and gas storage and separation station C-3 are connected in series to the pyrolysis oil and gas collection hole C-4 through the pyrolysis oil and gas collection pipeline C-1, and the pyrolysis oil and gas collection pipeline C-1 is distributed with openings corresponding to the pyrolysis oil and gas collection hole C-4.

[0082] The pyrolysis oil and gas collection pipeline C-1 and the high-temperature steam injection pipeline B-3 are staggered in the oil-rich coal reservoir in the oil-rich coal in-situ pyrolysis mining area E. The coal tar and coal gas precipitated from the fracture network of the oil-rich coal reservoir in the oil-rich coal in-situ pyrolysis mining area E underground are smoothly transported to the ground for pyrolysis oil and gas separation and storage.

[0083] like Figure 2 As shown in the figure, the pyrolysis semi-coke resource mining area D includes pyrolysis semi-coke mining working strips D-1 to D-6. Unmanned intelligent continuous mining equipment, coal-based solid waste materials and goaf filling system G are deployed in the strips to realize the intelligent mining of semi-coke resources and complete filling of goafs. The unmanned intelligent continuous mining equipment includes an intelligent excavator and anchor machine, a crusher, a transfer machine, a wet dust removal fan and a local ventilator.

[0084] The goaf filling system G is used to completely fill the goaf formed after the semi-coke mining in the pyrolysis semi-coke resource mining area D. It includes a gangue-concrete filling slurry preparation station G-1 and a grouting pipeline G-2. The gangue-concrete filling slurry preparation station G-1 includes a belt conveyor, a crusher, a concrete mixer and a high-pressure pump. The filling slurry preparation station G-1 is located in the return air lane A-8 on the side of the pyrolysis semi-coke resource mining area D, and the filling slurry is transported to the goaf of the pyrolysis semi-coke resource mining area D through the grouting pipeline G-2.

[0085] Each system of the present invention firstly adopts the systems of well-developed tunnels, in-situ mining area optimization, in-situ heat injection pyrolysis, pyrolysis oil and gas collection, etc. to realize the in-situ depolymerization of oil-rich coal to generate and extract coal tar and coal gas; then divide the in-situ pyrolysis mining area, pyrolysis semi-coke secondary mining, semi-coke resource intelligent mining and goaf filling, and finally realize the efficient in-situ pyrolysis of oil-rich coal, and fully exploit the oil-rich coal resources to the greatest extent. The well-developed in-situ pyrolysis + underground oil and gas collection and development method can effectively shorten the oil and gas transportation distance, and facilitate secondary heating and storage; it can not only greatly improve the efficiency and accuracy of engineering layout, but also help to increase the oil and gas output of pyrolysis of oil-rich coal; the well-developed in-situ pyrolysis technology provides open space conditions for the selection of heating methods and provides the shortest input time for heat input.

[0086] At the same time, in-situ pyrolysis of oil-rich coal and secondary mining of semi-coke are relatively independent systems. They are carried out in different areas and stages during the development process, and are equipped with complete ventilation systems to ensure the safety of the underground working environment. Secondly, the underground in-situ pyrolysis technology provides sufficient basic conditions for effective advance pre-cracking, optimization of heat injection methods and efficient transmission of thermal energy, which is conducive to ensuring efficient injection of carrier heat and sufficient depolymerization reaction of oil-rich coal in the pyrolysis mining area. Compared with traditional underground coal gasification technology, it has significant advantages in reducing ground subsidence, reducing overburden mining deformation, reducing geological environmental hazards, reducing energy consumption and carbon emissions, and has great potential for technical development.

[0087] like Figure 4 As shown, the embodiment of the present invention accordingly provides an oil-rich coal in-situ pyrolysis development layout and a semi-coke complete filling mining method, comprising the following steps:

[0088] Step 1: Optimization of in-situ pyrolysis mining area for oil-rich coal.

[0089] High-precision comprehensive exploration technology is used to conduct detailed exploration and evaluation of the coal quality characteristics and geological conditions of oil-rich coal. According to different resource endowments and geological conditions, geological resource evaluation and engineering adaptability evaluation are carried out in conjunction. Based on the evaluation results and the principles of in-situ pyrolysis mining area layout, the in-situ pyrolysis mining area for oil-rich coal wells is comprehensively determined.

[0090] The principles for selecting the in-situ pyrolysis mining area for oil-rich coal are:

[0091] (1) The coal quality, thickness, moisture content and other occurrence conditions of the oil-rich coal in the in-situ pyrolysis mining area are stable, and areas with complex geological structures such as faults, anticlines and synclines and hydrogeological conditions are avoided;

[0092] (2) The roof and floor rock layers of the oil-rich coal seams are dense rock layers with great thickness, high compressive strength, good air tightness, and good water-proof layers;

[0093] (3) Through grouting reinforcement, the oil-rich coal roof and bottom rock strata can be sealed, water-proof, and heat-insulating.

[0094] Step 2: Layout of pyrolysis reaction zone tunnels.

[0095] (1) According to the coal development and exploitation mode, the main shaft A-1, auxiliary shaft A-2, ventilation shaft A-3, main transport tunnel A-5, auxiliary transport tunnel A-6 and main return air tunnel A-4 standard tunnel layout are excavated, and a complete ventilation system is formed; then it is divided into several in-situ pyrolysis working faces along the inclination direction of the coal seam, and the transport tunnel A-7 and return air tunnel A-8 are excavated. After the shaft, main tunnel, transport tunnel A-7 and return air tunnel A-8 are connected, the ventilation route of the pyrolysis working face is: main shaft A-1, auxiliary shaft A-2 → main transport tunnel A-5 → auxiliary transport tunnel A-6 → transport tunnel A-7 → return air tunnel A-8 → main return air tunnel A-4 → ventilation shaft A-3 → ground.

[0096] (2) A filling insulation layer F-1 is constructed at the boundary of the working face E in the oil-rich coal in-situ pyrolysis mining area, near the stop-mining line, and on the side of the coal wall of the upper and lower horizontal tunnels. At the same time, directional drilling equipment is used to drill and grout the coal seam roof and floor rock strata to form a grouting water-blocking and heat-insulating layer F-2. The in-situ pyrolysis working face E in the oil-rich coal in-situ pyrolysis mining area is sealed from all sides by the filling insulation layer F-1 and the grouting water-blocking and heat-insulating layer F-2.

[0097] (3) The working face of the oil-rich coal in-situ pyrolysis mining area E is divided into working strips of a certain width along the strike direction. The measure tunnel A-9 is excavated to separate the working strips to form several strip-type pyrolysis mining areas. At the same time, pre-splitting boreholes B-2 and oil and gas collection boreholes C-4 are constructed on both sides of the coal wall of the measure tunnel A-9. The oil-rich coal reservoir is pre-splitting using a controllable shock wave or hydraulic fracturing device B-1 to form a coal seam fracture network.

[0098] In order to ensure the effect of artificial pre-cracking, the E working face of the oil-rich coal in-situ pyrolysis mining area is divided into strip-type pyrolysis mining areas along the strike, with a strip width of 8 to 15 m, an excavation measure tunnel width of 3 to 5 m, and a pre-cracking borehole B-2 and an oil and gas collection borehole C-4 depth of 4 to 8 m; among them, the pre-cracking borehole B-2 and the pyrolysis oil and gas collection hole C-4 are arranged at intervals up and down, and the horizontal spacing of the boreholes is 1 to 2 m.

[0099] (4) High-temperature steam injection pipeline B-3 and pyrolysis oil and gas collection pipeline C-1 are arranged in the pre-splitting borehole B-2 and the oil and gas collection hole C-4, and are respectively connected to the transport tunnel A-7 and the return air tunnel A-8, and are connected to the high-temperature steam heating device B-5 in the tunnel and the pyrolysis oil and gas pipeline secondary heating device C-2. In order to reduce energy loss during pyrolysis and improve pyrolysis efficiency, after the corresponding pyrolysis high-temperature steam injection pipeline B-3 and pyrolysis oil and gas collection pipeline C-1 are arranged, a filling insulation layer F-1 is arranged in the measure tunnel A-9, and the oil-rich coal in-situ pyrolysis mining area E is completely closed by the filling insulation layer F-1 and the grouting water-blocking insulation layer F-2, forming a number of strip-type pyrolysis mining areas arranged along the strike.

[0100] Step 3: In-situ heat injection pyrolysis.

[0101] (1) A high-temperature steam heating device B-5 and a secondary heating device C-2 for the pyrolysis oil and gas pipeline are arranged in the horizontal tunnel of the E working face of the oil-rich coal in-situ pyrolysis mining area underground. The high-temperature steam heating device B-5 and the secondary heating device C-2 for the pyrolysis oil and gas pipeline are respectively connected to the high-temperature steam injection pipeline B-3 and the pyrolysis oil and gas collection pipeline C-1 led out from the measure tunnel A-9.

[0102] (2) The required power resources are provided by the underground substation B-4, and high-temperature steam is generated by the high-temperature steam heating device B-5. The high-temperature steam is injected into the fracture network of the oil-rich coal reservoir through the high-temperature steam injection pipeline B-3. The heat transfer between the heat carrier fluid and the coal body stimulates the pyrolysis reaction of the oil-rich coal, and the oil-rich coal reservoir continuously precipitates coal tar and coal gas.

[0103] (3) The in-situ pyrolysis process of oil-rich coal is completed by extracting and transporting the oil and gas through the pyrolysis oil and gas collection pipeline C-1 and transporting it through the underground pyrolysis oil and gas pipeline secondary heating device C-2 to the ground pyrolysis oil and gas storage and separation station C-3.

[0104] Step 4: Unmanned intelligent mining of pyrolysis semi-coke resources.

[0105] The oil-rich coal is pyrolyzed in situ to form pyrolytic semi-coke resources, which retain the integrity of its blocks and segments. Its strength is greatly reduced compared to before pyrolysis, and pyrolytic semi-coke resource mining operations can be carried out.

[0106] After the oil-rich coal is in-situ pyrolyzed, the high-temperature steam heating system B and the pyrolysis oil and gas collection system C are moved to the next oil-rich coal in-situ pyrolysis mining area E, and the in-situ heat injection pyrolysis is repeated;

[0107] The in-situ pyrolysis mining area E of the oil-rich coal is removed from the high-temperature steam heating system B and the pyrolysis oil and gas collection system C to form the pyrolysis semi-coke resource mining area D; the coal wall filling insulation layer of the transport level tunnel is removed, and the pyrolysis semi-coke resources formed after in-situ pyrolysis in the pyrolysis semi-coke resource mining area D are mined.

[0108] The specific steps include:

[0109] (1) According to the strip pyrolysis mining area, the strip operation sequence of pyrolysis semi-coke mining is divided into: Figure 2 As shown;

[0110] (2) Remove the coal wall filling insulation layer F-1 of the transport tunnel A-7 of the pyrolysis semi-coke resource mining working face in the oil-rich coal in-situ pyrolysis mining area E. With the support of the filling insulation layer F-1 on both sides, arrange the mining working strips D-1 to D-6 in the pyrolysis semi-coke resource mining area D. Deploy the intelligent integrated excavator and anchor machine, transfer machine, crusher, retractable belt conveyor, local ventilator, and dust removal equipment in the mining working strip D-1;

[0111] (3) An intelligent remote-controlled integrated mining and anchoring machine is used for mining and support operations. After being crushed by a crusher, the semi-coke resources are transported to the transport level A-7 by a transfer machine, and then lifted to the ground via a retractable belt conveyor and the main shaft A-1. During the mining operation, local ventilators and wet dust removal fans are used to ventilate and remove dust in the mining working strip D-1.

[0112] During the normal mining period of pyrolysis semi-coke resources, the transportation route is: mining working strip D-3 → transfer machine → transport level tunnel A-7 → main transport tunnel A-5 → main shaft A-1 → ground.

[0113] The ventilation route is: auxiliary transport tunnel A-6 → transport horizontal tunnel A-7 → mining working strip D-3 → return air horizontal tunnel A-8 → main return air tunnel A-4.

[0114] Step 5: Completely fill the goaf.

[0115] After the pyrolysis semi-coke resources are mined, a goaf is formed, and the goaf is completely filled, which specifically includes the following steps:

[0116] (1) In the return air lane A-8 of the D working face of the pyrolysis semi-coke mining system, a filling slurry preparation station G-1 consisting of a coal-based solid waste material conveyor, a crusher, a concrete mixer, and a high-pressure pump station is arranged. Figure 2 As shown;

[0117] The filling slurry selects coal gangue as the filling material and cement as the binder, which are mixed according to the set ratio to form the cementing filling material. In order to ensure the slurry transportation process and slurry strength, the coal gangue needs to be graded and crushed, and the particle size of the crushed coal gangue is required to not exceed 15mm.

[0118] (2) Install the backfill support baffle in the goaf. The gangue and concrete are transported from the auxiliary transport tunnel A-3 to the underground gangue-concrete backfill slurry preparation station G-1. The gangue is crushed by a crusher and mixed with concrete. The backfill slurry is prepared by a concrete mixer. The backfill slurry is transported to the working strip D-1 of the goaf through the grouting pipeline G-2 to complete the backfilling of the goaf.

[0119] (3) The filling slurry is transported to the goaf through the grouting pipeline G-2 for complete filling of the goaf. After the mining-filling operation, the pyrolysis semi-coke resource strips are completely replaced by dense filling bodies.

[0120] Furthermore, the intelligent mining operation of pyrolysis semi-coke resources and the complete filling operation of the goaf are carried out simultaneously without interfering with each other, forming an intelligent mining method for complete filling of pyrolysis semi-coke resources in parallel with mining and filling, and the specific process is as follows:

[0121] (1) The mining work strips that have been divided are used for pyrolysis semi-coke mining, and are numbered D-1 to D-6 along the strike direction. The intelligent pyrolysis semi-coke mining operation is carried out in an "interval skipping" manner, starting with mining work strip D-1;

[0122] (2) After the mining of the mining working strip D-1 is completed, a goaf is formed. The mining equipment is removed and both ends of the goaf are closed. Filling equipment and transportation pipelines are arranged to completely fill the goaf. After the slurry solidifies for a certain period of time, the support strength can be reached and a dense filling body is formed in the goaf.

[0123] (3) While the backfilling operation is being carried out in the goaf, the pyrolysis semi-coke resource intelligent mining operation is carried out in the mining work strip D-3. The mining operation and backfilling operation are carried out in two non-adjacent strips to ensure the continuity of the semi-coke resource mining and the goaf backfilling operation in time and space and the relative independence in space;

[0124] (4) The order of pyrolysis semi-coke resource mining: mining working strip D-1→D-3→D-5→D-2→D-4→D-6; the order of complete filling: goaf strip D-1→D-3→D-5→D-2→D-4→D-6. When the filling operation of the goaf mining working strips D-1, D-3, and D-5 is completed and the filling material slurry solidifies to form a dense filling body, the pyrolysis semi-coke resource intelligent mining operation and goaf complete filling operation are carried out on the mining working strips D-2, D-4, and D-6 until the slurry of the mining working strips D-2, D-4, and D-6 solidifies to form a dense filling body, and the complete filling and intelligent mining of semi-coke resources in the pyrolysis reaction area is completed.

[0125] The present invention is not limited to the above-mentioned embodiments. On the basis of the technical solution disclosed in the present invention, technicians in this field can make some substitutions and deformations to some technical features therein according to the disclosed technical content without creative labor, and these substitutions and deformations are all within the protection scope of the present invention.

Claims

1. An oil-rich coal in-situ pyrolysis development layout and semi-coke full filling mining system, characterized in that: Includes above-ground and underground parts; The above-the-hole part includes: a pyrolysis oil and gas collection system (C), which is used to transport the coal tar and coal gas generated by in-situ depolymerization of the collected pyrolysis oil-rich coal to a surface oil and gas separation station through a pyrolysis oil and gas collection pipeline; The underground part includes: The tunnel layout system (A) is used to divide the oil-rich coal in-situ pyrolysis mining area (E) and the pyrolysis semi-coke resource mining area (D) to carry out the layout of the tunnels for the in-situ pyrolysis development of the oil-rich coal; The oil-rich coal in-situ pyrolysis mining area (E) is used to separate coal tar and coal gas from the underground oil-rich coal reservoir through the fracture network of the high-temperature steam heating system (B); A high-temperature steam heating system (B) is arranged on the working face of the oil-rich coal in-situ pyrolysis mining area (E), and is used to pre-crack and generate a fracture network in the oil-rich coal reservoir by means of a fracturing device, and high-temperature steam is injected into the fracture network of the oil-rich coal reservoir; Pyrolysis semi-coke resource mining area (D), used for intelligent mining of pyrolysis semi-coke resources; The insulation system (F) is used to construct a filling body at the working face of the oil-rich coal in-situ pyrolysis mining area (E) for drilling and grouting sealing operations on the roof and floor rock layers of the coal seam; The goaf filling system (G) is used to completely fill the goaf formed after the pyrolysis semi-coke resource mining area (D) is mined.

2. The oil-rich coal in-situ pyrolysis development layout and semi-coke full filling mining system according to claim 1 is characterized in that: The tunnel layout system (A) includes the main shaft, auxiliary shaft, ventilation shaft, main return air shaft, main transport shaft, auxiliary transport shaft, transport level shaft, return air level shaft and measure shaft; the main shaft, auxiliary shaft and ventilation shaft are excavated from the ground, and the auxiliary shaft and ventilation shaft are located on both sides of the main shaft respectively; the main return air shaft, main transport shaft and auxiliary transport shaft are arranged in parallel and connected with the ventilation shaft, main shaft and auxiliary shaft respectively; The transport lane and the return air lane are arranged in parallel and located on both sides of the working face of the pyrolysis semi-coke resource mining area (D) and the working face of the oil-rich coal in-situ pyrolysis mining area (E), and are vertically connected with the main return air lane, the main transport lane and the auxiliary transport lane; The measures tunnel is arranged along the working faces of the pyrolysis semi-coke resource mining area (D) and the oil-rich coal in-situ pyrolysis mining area (E), and is connected with the return air tunnel and the transport tunnel respectively, dividing the mining area into strip mining areas.

3. The oil-rich coal in-situ pyrolysis development layout and semi-coke full filling mining system according to claim 1 is characterized in that: The high-temperature steam heating system (B) includes a fracturing device, a high-temperature steam injection pipeline, an underground substation and a high-temperature steam heating device; The fracturing device, the high-temperature steam heating device and the underground substation are located in the transport level tunnel on the working face side of the oil-rich coal in-situ pyrolysis mining area (E); a plurality of high-temperature steam injection holes distributed in an array are arranged on the coal wall of the oil-rich coal in-situ pyrolysis mining area (E), and the boreholes are interconnected through a high-temperature steam injection pipeline, and openings corresponding to the high-temperature steam injection holes are distributed on the steam injection pipeline; the high-temperature steam injection pipeline is connected to the high-temperature steam heating device and the fracturing device; The underground substation is electrically connected to the fracturing device and the high-temperature steam heating device.

4. The oil-rich coal in-situ pyrolysis development layout and semi-coke full filling mining system according to claim 1 is characterized in that: a pyrolysis oil and gas collection system (C), comprising a pyrolysis oil and gas collection pipeline, a pyrolysis oil and gas pipeline secondary heating device, a pyrolysis oil and gas storage and separation station, and a pyrolysis oil and gas collection hole; The pyrolysis oil and gas storage and separation station is located on the ground, the pyrolysis oil and gas pipeline secondary heating device is deployed in the return air lane, the pyrolysis oil and gas collection hole is located in the coal wall of the in-situ pyrolysis mining area (E) of the oil-rich coal, the pyrolysis oil and gas pipeline secondary heating device and the pyrolysis oil and gas storage and separation station are connected to the pyrolysis oil and gas collection hole through the pyrolysis oil and gas collection pipeline, and the pyrolysis oil and gas collection pipeline is distributed with openings corresponding to the pyrolysis oil and gas collection hole; The pyrolysis oil and gas collection pipelines and the high-temperature steam injection pipelines are staggeredly distributed in the oil-rich coal reservoir in the oil-rich coal in-situ pyrolysis mining area.

5. The oil-rich coal in-situ pyrolysis development layout and semi-coke full filling mining system according to claim 1 is characterized in that: The pyrolysis semi-coke resource mining area (D) includes mining working strips and unmanned intelligent mining equipment; the unmanned intelligent continuous mining equipment includes an intelligent integrated excavator and anchor machine, a crusher, a transfer machine, a wet dust removal fan and a local ventilator.

6. The oil-rich coal in-situ pyrolysis development layout and semi-coke full filling mining system according to claim 1 is characterized in that: The goaf filling system (G) includes a gangue-concrete filling slurry preparation station and a grouting pipeline; the filling slurry preparation station is located in the return air level tunnel on the side of the pyrolysis semi-coke resource mining area (D), and the filling slurry is transported to the goaf of the pyrolysis semi-coke resource mining area (D) through the grouting pipeline.

7. An in-situ pyrolysis development layout of oil-rich coal and a method for full filling of semi-coke for mining according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1, Optimization of in-situ pyrolysis mining area for oil-rich coal: Conduct detailed exploration and evaluation of the coal quality characteristics and geological conditions of oil-rich coal; carry out geological resource evaluation and engineering adaptability evaluation according to different resource occurrences and geological conditions; comprehensively determine the in-situ pyrolysis mining area of ​​oil-rich coal mines based on the evaluation results and the in-situ pyrolysis mining area layout principles; S2, pyrolysis reaction zone tunnel layout: In the oil-rich coal mine, the in-situ pyrolysis working face is excavated to form a tunnel layout, several pyrolysis reaction zones are divided along the inclination direction of the coal seam, and the measure tunnels are excavated to form a complete tunnel layout system; The oil-rich coal in-situ pyrolysis mining area (E) is divided into working strips along the strike through the measure tunnel, and the oil-rich coal reservoir is pre-cracked by the fracturing device to form a fracture network of the oil-rich coal reservoir; Drill holes in the coal wall in the tunnel to connect and lay high-temperature steam injection pipelines and pyrolysis oil and gas collection pipelines; Construct a filling insulation layer for the working face of the oil-rich coal in-situ pyrolysis mining area (E), and construct a grouting water-blocking insulation layer for the coal seam roof and floor rock strata in the pyrolysis reaction area; Arrange filling insulation layers on both sides of the coal wall of the working strip of the oil-rich coal in-situ pyrolysis mining area (E) to form a number of oil-rich coal in-situ pyrolysis mining area strips arranged along the strike; S3, in-situ heat injection pyrolysis: A high-temperature steam heating device and an underground substation are arranged in the transport lane of the working face of the oil-rich coal in-situ pyrolysis mining area (E), and connected with the high-temperature steam injection pipeline to form a high-temperature steam heating system; high-temperature steam is injected into the oil-rich coal reservoir fracture network to cause a pyrolysis reaction of the oil-rich coal, and coal tar, coal gas and solid semi-coke are precipitated from the oil-rich coal reservoir fracture network; the coal tar and coal gas are transported to the ground pyrolysis oil and gas separation station, and the pyrolysis oil and gas are stored; S4, pyrolysis coke resource exploitation: After the oil-rich coal is in-situ pyrolyzed, the high-temperature steam heating system (B) and the pyrolysis oil and gas collection system (C) are moved to the next oil-rich coal in-situ pyrolysis mining area (E), and the in-situ heat injection pyrolysis is repeated; The oil-rich coal in-situ pyrolysis mining area (E) is removed from the high-temperature steam heating system (B) and the pyrolysis oil and gas collection system (C) to form a pyrolysis semi-coke resource mining area (D); The heat insulation layer of the coal wall filling in the transport lane is removed, and the pyrolysis semi-coke resources formed after in-situ pyrolysis in the pyrolysis semi-coke resource mining area (D) are mined; Intelligent mining equipment is deployed in the mining work strip of the pyrolysis semi-coke resource mining area (D) to carry out unmanned intelligent mining of pyrolysis semi-coke resources; S5, goaf is completely filled: After the pyrolysis semi-coke resources are mined, the goaf strip is completely filled, and the filling equipment is arranged in the return air level tunnel to transport the filling slurry to the goaf area for complete filling operation; Since then, the in-situ pyrolysis development layout of oil-rich coal and the complete filling and mining of semi-coke resources have been completed.

8. The in-situ pyrolysis development layout of oil-rich coal and the semi-coke full-filling mining method according to claim 7 is characterized in that: In S1, the principles for selecting the in-situ pyrolysis mining area for oil-rich coal are: ① The coal quality, thickness and moisture content of the oil-rich coal in the in-situ pyrolysis mining area are stable, and the presence of faults, anticlines and synclines is avoided; ② The roof and floor rock layers of the oil-rich coal seam are dense rock layers that meet the requirements of thickness, compressive strength and air tightness, and there are water-proof layers; ③Through grouting reinforcement, the oil-rich coal roof and bottom rock strata can be sealed, water-proof, and heat-insulating.

9. The in-situ pyrolysis development layout of oil-rich coal and the semi-coke full-filling mining method according to claim 7, characterized in that: In step S2, the pyrolysis reaction zone tunnels are arranged to form a complete ventilation system at the working face of the mining area. The ventilation route of the working face is: main shaft, auxiliary shaft → main transport tunnel → auxiliary transport tunnel → transport level tunnel → return air level tunnel → main return air tunnel → air shaft → ground; In step S4, during the normal mining period of pyrolysis semi-coke resources, the transportation route is: mining working strip → transfer machine → transportation level tunnel → main transportation tunnel → main shaft → ground; The ventilation route is: auxiliary transport tunnel → transport tunnel → mining working strip → return air tunnel → main return air tunnel.

10. The in-situ pyrolysis development layout of oil-rich coal and the semi-coke full-filling mining method according to claim 7, characterized in that: In step S5, the goaf is completely filled, and the intelligent mining operation of pyrolysis semi-coke resources and the goaf complete filling operation are carried out simultaneously without interfering with each other, including: The "interval skipping" method is adopted along the mining work strip to carry out intelligent mining of pyrolysis semi-coke in the pyrolysis semi-coke resource mining area (D); After the mining of each mining strip is completed, a goaf is formed. The mining equipment is removed and both ends of the goaf are closed. Filling equipment and transportation pipelines are arranged to completely fill the goaf. After the slurry solidifies for a certain period of time, the support strength can be reached, and a dense filling body is formed in the goaf. While filling the goaf, pyrolysis semi-coke mining is carried out in the interval strips. The mining and filling operations are carried out in two non-adjacent strips. The semi-coke resource mining and goaf filling operations are continuous in time and space and relatively independent in space. After the strip slurry solidifies to form a dense filling body, the semi-coke resources in the pyrolysis reaction zone are completely filled and the intelligent mining work is completed.

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