Method for converting coal bed gas by using novel catalyst
Technical Field
The invention relates to the field of coal mine gas extraction, in particular to a method for converting coal bed gas by using a novel catalyst.
Background
Gas is also called coal bed gas as one of main disasters in coal mine safety production, in recent years, as the mining intensity and the mining depth of coal mines in China are continuously increased and are influenced by high ground stress, high gas pressure and high gas content, the coal mine gas disasters gradually become main contents of mine disasters, and meanwhile, the gas is used as an energy substance, and due to the influences of factors such as high collection difficulty, high storage risk and the like, the utilization rate of the gas is extremely low, and a large amount of waste of the energy substance is caused. The gas extraction is used as an important means for preventing gas accidents, so that the gas content of the coal bed can be greatly reduced, and the gas resource can be collected and utilized.
At present, the commonly used gas extraction means in China are as follows: hydraulic fracturing, deep hole pre-fracturing blasting and gas drainage drilling, wherein the hydraulic fracturing injects a large amount of water into a coal body to cause too high humidity during working face stoping, so that the production efficiency is influenced; explosive is needed for deep hole pre-splitting blasting, and gas disasters caused by open fire are easy to generate; the gas extraction efficiency of the gas extraction hole in a free state is high by extracting gas through the internal and external pressure difference of the coal body, and the extraction effect of the gas attached to the coal body is greatly reduced.
In conclusion, the existing gas extraction method has the problems that the safe and efficient gas extraction cannot be effectively solved, and the subsequent coal mining environment is affected.
Disclosure of Invention
The invention aims to provide a method for converting coal bed gas by adopting a novel catalyst, which not only can safely and efficiently extract coal bed gas and reduce the danger of gas, but also can improve the production condition of a working face and provide a good operation environment for subsequent mining.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a method for converting coal bed gas by using a novel catalyst comprises the following steps:
(1) arranging a series of drilling sites on a coal seam to be mined, and arranging bedding drill holes on the coal seam through the drilling sites;
(2) injecting a solution containing a catalyst into a coal seam to be mined along a drill hole through a catalyst injection system, directly oxidizing gas in the coal seam into methanol under the catalytic action, and dissolving the methanol in the catalyst solution, wherein the catalyst is an iridium catalyst containing a 2-methyl phenanthroline ligand;
(3) the methanol solution containing the catalyst is extracted from the coal bed through liquid extraction equipment, the catalyst and the methanol solution are separated through an underground separation system, the separated catalyst solution is injected into the coal body again, the catalyst is recycled, and the purified methanol solution is stored in a methanol storage tank.
Further, step (1) arranges a series of drill sites in the driving roadway of the working face to be mined, and the operation steps are as follows: firstly, arranging a series of drilling sites on one side of a working face to be mined, arranging a series of liquid injection holes in the drilling sites, and injecting a solution containing a catalyst into a coal body; thirdly, arranging a series of drilling sites on the other side of the working face to be mined, and arranging a series of liquid extraction holes in the drilling sites for extracting the catalyst solution containing the methanol after the reaction with the coal gas is finished.
Furthermore, the catalyst injection system comprises raw material preparation equipment, mixing equipment, pumping equipment and liquid injection equipment, wherein all the equipment is positioned in the large roadway chamber of the track. Wherein raw materials preparation equipment includes that the catalyst prepares equipment and water supply installation, compounding equipment is including stirring pond and mixer, pumping equipment includes high-pressure pump and pumping controller, and the output that equipment and water supply installation were prepared to the catalyst communicates the feed end in stirring pond respectively, stirs the pond and connects the mixer, and the entry of pipe connection high-pressure pump is passed through to the discharge gate in stirring pond, and the liquid equipment is annotated through the pipe connection in the export of high-pressure pump, and the pumping controller sets up on the pipeline between high-pressure pump and liquid equipment.
Preferably, the underground separation system comprises a separation device and a purification device, an inlet of the separation device is connected with the liquid extraction device, a liquid phase outlet of the separation device is connected with an inlet of the purification device, and an outlet of the purification device is connected with the methanol storage tank.
Preferably, the purification equipment is rectification purification equipment.
The iridium catalyst containing the 2-methyl phenanthroline ligand has the working principle that one of three carbon-hydrogen bonds in a methyl group is broken by virtue of iridium, namely, a hydrogen atom in the methyl group is cut off, then a boron compound is inserted, the boron compound can be easily substituted by other more complex chemical groups, the novel catalyst is easy to operate, and various chemical substances can be attached to any type of carbon-hydrogen bonds by virtue of a catalytic reaction generated by the novel catalyst. The catalyst can directly catalyze and oxidize methane into methanol.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the invention, a solution containing a catalyst is injected into a coal body through a high-pressure pump, so that on one hand, the coal body crack is enlarged, and the catalyst solution and the gas on a working face to be mined are fully reacted; on the other hand, the catalyst solution fully reacts with the gas in the coal body through the cracks, and the gas extraction efficiency is improved.
2. According to the invention, gas state gas is converted into liquid state methanol solution, the extraction safety is obviously improved, and the injected catalyst solution can not only react with free methane molecules, but also react with methane molecules attached to the surface of a coal body, so that the gas extraction efficiency is obviously improved; the solution containing the catalyst is injected into the coal body, so that the humidity of the coal body is improved, the fire hazard of the coal body is reduced, and meanwhile, the water absorbs heat, so that the hazard of gas disasters is reduced.
Drawings
FIG. 1 is a plan view of a catalyst withdrawal system;
FIG. 2 is a cross-sectional view of a drill site layout of a face to be mined;
in the figure: 1-rail climbing, 2-transportation climbing, 3-working face rail lane, 4-rubber belt transportation lane, 5-rail lane, 6-methanol storage tank, 7-purification equipment, 8-separation equipment, 9-stirring tank, 10-stirrer, 11-high pressure pump, 12-pumping controller, 13-water supply equipment, 14-catalyst preparation equipment, 15-liquid injection equipment, 16-drilling machine, 17-hole sealing material, 18-liquid pumping equipment, 19-air pressure pump, 20-chamber, 21-connection lane and 22-working face transportation lane.
Detailed Description
The invention is described in further detail below with reference to the figures and specific examples.
The embodiment provides a method for converting coal bed gas by using a novel catalyst, which comprises the following steps: (1) arranging a series of drilling sites on a coal seam to be mined, and arranging bedding drill holes on the coal seam through the drilling sites; (2) injecting a solution containing a catalyst into a coal seam to be mined along a drill hole by using a catalyst solution injection system, catalyzing gas in the coal seam into methanol and dissolving the methanol in the catalyst solution; (3) the catalyst solution containing the methanol is extracted from the coal bed through liquid extraction equipment, the methanol and the catalyst solution are separated through an underground separation system, the separated catalyst solution is injected into the coal body again, the catalyst solution is recycled, and the purified methanol solution is stored in a methanol storage tank.
Specifically, a catalyst drainage system is arranged in the track roadway chamber before gas extraction, as shown in fig. 1-2, and comprises a catalyst injection system, a liquid extraction device, a downhole separation system and a methanol storage tank 6. The catalyst injection system comprises raw material preparation equipment, mixing equipment, pumping equipment and liquid injection equipment 15, wherein the raw material preparation equipment comprises catalyst preparation equipment 14 and water supply equipment 13, the mixing equipment comprises a stirring pool 9 and a stirrer 10 and is used for mixing water and a catalyst, and the pumping equipment comprises a high-pressure pump 11 and a pumping controller 12 and is used for pumping a catalyst solution. The underground separation system comprises a separation device 8 and a purification device 7, wherein the separation device 8 is used for separating the catalyst from the reacted methanol solution, and the purification device 7 is used for purifying the methanol solution.
The output of equipment 14 is prepared to the catalyst and water supply equipment 13 communicates the feed end of stirring pond 9 respectively, and stirring pond 9 connects mixer 10, and the discharge gate of stirring pond passes through the entry of pipe connection high-pressure pump 11, and pipe connection notes liquid equipment 15 is passed through in the export of high-pressure pump 11, and notes liquid equipment 15 passes through the pipe connection and annotates the liquid mouth, and pumping controller 12 sets up on the pipeline between high-pressure pump 11 and notes liquid equipment 15, the entry of drawing liquid equipment 18 passes through the pipe connection and draws liquid mouth, and the exit linkage splitter 8 of drawing liquid equipment 18, the entry of the liquid phase exit linkage purification equipment 7 of splitter 8, the exit linkage methyl alcohol holding vessel 6 of purification equipment 7.
The catalyst solution injection system route is as follows: chamber → communication lane → rubber belt transportation lane → transportation mountain → working face transportation lane; the catalyst solution pumping system route is as follows: working face track lane → track mountain → track main lane → chamber, thereby forming a closed circulation system.
The method comprises the following specific steps:
(1) respectively injecting the catalyst and water into a stirring pool 9 by a catalyst preparation device 14 and a water supply device 13, turning on a switch of a stirrer 10 to fully mix the catalyst and the water to prepare a solution containing the catalyst, turning on a high-pressure pump 11 and a pumping controller 12, and injecting the solution containing the catalyst into the coal to be mined through a chamber 20, a connection roadway 21, a belt transportation main roadway 4, a transportation mountain 2 and a working face transportation roadway 22;
(2) arranging a series of drill sites on one side of a working face to be mined in advance, arranging bedding drill holes I, namely liquid injection holes, on the drill sites through a drilling machine 16, injecting a solution containing a catalyst into the working face to be mined through a liquid injection device 15, injecting fresh air into coal bodies through an air pressurizing pump 19 after liquid injection is completed, and sealing the liquid injection holes by using a hole sealing material 17 after the liquid injection is completed to prevent the solution containing the catalyst and air from flowing outwards;
(3) after reacting for a period of time, arranging a drill site and a bedding drilling hole II, namely a liquid pumping port, on the other side of the working face to be mined, pumping a methanol solution containing a catalyst by a liquid pumping device 18 through the drilling hole, sequentially delivering the methanol solution to a separation device 8 through a working face track roadway 3, a track ascending roadway 1, a track main roadway 5 and a chamber 20, separating the methanol solution from the catalyst by the separation device 8, re-injecting the catalyst into a stirring pool 9, further injecting the methanol separated by the separation device 8 into a purification device 7, increasing the concentration of the methanol, and storing the high-concentration methanol into a methanol storage tank 6.
The methanol is recovered from the methanol aqueous solution by generally adopting a rectification purification mode, and the purification equipment 7 is preferably rectification purification equipment.