An underground coal gasification simulation device

Abstract

The application discloses a coal underground gasification simulation device, which comprises a gasification furnace, a plurality of jacks arranged in the gasification furnace, a bearing plate arranged on the jacks, a sample coal seam arranged above the bearing plate, a gasification channel arranged in the sample coal seam, an air inlet pipeline and an air outlet pipeline arranged at two ends of the gasification channel respectively, wherein the air inlet pipeline and the air outlet pipeline extend to the surface of the gasification furnace, a plurality of thermocouples arranged on the two sides of the sample coal seam, and the thermocouples connected to the gasification furnace; and a gasification agent generating assembly connected to the air inlet pipeline through a pipeline and used for injecting gas into the gasification furnace. The application further discloses a coal underground gasification simulation method. The application can adjust the coal seam inclination, simulate the gasification process of different inclination coal seams under geological conditions, adjust the water injection amount and distribution characteristics in the gasification process, maintain the stability of the gasification process and improve the gasification efficiency.

Description

Technical Field

[0001] This invention relates to the field of underground coal gasification simulation experiment technology, and in particular to an underground coal gasification simulation device. Background Technology

[0002] Underground coal gasification technology primarily involves "igniting" coal in situ underground, causing an oxidation-reduction reaction that produces large quantities of combustible gas that is transported to the surface for utilization. Underground coal gasification is influenced by numerous factors, particularly the structural characteristics of the coal seam and the type of gasifying agent; currently, experiments are mainly conducted using simulation devices.

[0003] Current simulation devices and experimental methods for underground coal gasification rarely simulate the underground coal gasification process under different inclination angles. Furthermore, the gasification process exhibits weak stability, short duration, low conversion efficiency, and poor calorific value and composition of the coal gas. Therefore, developing an underground coal gasification simulation device is an urgent need in the field of underground coal gasification technology. Summary of the Invention

[0004] The purpose of this invention is to provide a coal underground gasification simulation device to address the problems that current coal underground gasification simulation devices cannot simulate the coal underground gasification process under different inclination angles, and that the gasification process is unstable, has a short duration of continuous gasification, and has low gasification conversion efficiency.

[0005] To achieve the above objectives, in one respect, the present invention provides a coal underground gasification simulation device, comprising:

[0006] A gasifier is provided, which contains multiple jacks, each with a support plate. A sample coal layer is located above the support plate, and a gasification channel is provided within the sample coal layer. An inlet pipe and an outlet pipe are respectively provided at both ends of the gasification channel, and both the inlet pipe and the outlet pipe extend to the surface of the gasifier. Several thermocouples are provided on both sides of the sample coal layer and are connected to the gasifier.

[0007] A gasifying agent generating assembly, which is connected to the gas inlet pipe via a pipeline for injecting gas into the gasifier;

[0008] A water supply assembly, comprising a water injection port disposed in the gasifier, the water injection port being connected to a plurality of atomizing nozzles inside the gasifier, the atomizing nozzles being located within the gasification channel;

[0009] An ignition device is provided, located near the bottom of the air intake pipe, for igniting the sample coal seam.

[0010] As a further description of the above technical solution:

[0011] The vaporizing agent generating assembly includes a nitrogen cylinder, an oxygen cylinder, and an air cylinder, and valves are provided between the nitrogen cylinder, the oxygen cylinder, and the air cylinder and the pipeline.

[0012] As a further description of the above technical solution:

[0013] At least one airflow baffle is provided in the vaporization channel, and the airflow baffle is connected to a roller, which is movably connected in the vaporization channel.

[0014] As a further description of the above technical solution:

[0015] Both the air inlet pipe and the air outlet pipe are equipped with flow meters.

[0016] As a further description of the above technical solution:

[0017] A compressible sealing ring is provided between the support plate and the gasifier.

[0018] As a further description of the above technical solution:

[0019] The gasifier includes a gasifier body and a furnace cover, the furnace cover being detachably connected to the gasifier body.

[0020] As a further description of the above technical solution:

[0021] A graphite sealing ring is provided between the furnace cover and the gasification furnace body.

[0022] As a further description of the above technical solution:

[0023] The sample coal seam is provided with a roof plate at the top and a bottom plate at the bottom, and a topsoil layer is provided on the roof plate.

[0024] As a further description of the above technical solution:

[0025] It also includes a computer, and the thermocouple, the jack and the atomizing nozzle are all connected to the computer for control.

[0026] On the other hand, the present invention also discloses a simulation method for an underground coal gasification simulation device, which specifically includes the following steps:

[0027] Step 1: Select the sample coal for the experiment, arrange the sample coal bed and gasification channel, and select the inclination angle for the experiment.

[0028] Step 2: Drill holes in the sample coal seam at the bottom of the gasification channel using an electric drill, and arrange several thermocouples. Connect the thermocouple signal lines to accurately identify the data measured by each thermocouple.

[0029] Step 3: Set up an airflow baffle, which is connected to a roller via a rope; the thermocouple feeds the temperature feedback to the computer, which processes the data to determine the moving distance, and the roller rotates to move the airflow baffle.

[0030] Step 4: Arrange the sample coal seam in the upper part of the gasification channel, drill holes using an electric drill, install several thermocouples and water injection pipes, and install atomizing nozzles in the upper part of the gasification channel;

[0031] Step 5: Arrange the coal seam roof and topsoil, place water injection pipes on the upper part of the roof, and place the furnace cover and graphite sealing ring at the same time. The furnace cover is connected to the gasifier body by a clamp.

[0032] Step Six: The gasifying agent generating component charges the gasifier with gas, and then the ignition device is activated to ignite the sample coal seam.

[0033] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0034] 1. In this invention, four adjustable jacks are added to enable precise angle control and simulate geological conditions at different angles, thereby more closely reflecting actual geological conditions.

[0035] 2. In this invention, the water injection device and the water injection point are changed, which has the following beneficial effects:

[0036] a. The water injection point is moved from the lower part of the top plate to the upper part of the gasification channel. The purpose is to be closer to the gasification working surface, so that water vapor can quickly participate in the gasification reaction while achieving precise control of the injected water volume, thereby enhancing the stability of the gasification process.

[0037] b. The water injection device is changed from an ordinary device to an atomizing injection device. The purpose is to vaporize water into fine and uniform particles. The atomized water particles are small and easily undergo phase change, which can quickly participate in the vaporization reaction, enhance the stability of the vaporization process, and maintain a longer vaporization time.

[0038] c. The atomizing device is equipped with 9 nozzles, which can achieve 360-degree atomization spray. Its purpose is to ensure that the gasification reaction in the oxidation zone is sufficient, while controlling the reasonable ratio of the three zones to provide sufficient energy for the reduction zone and the dry distillation zone.

[0039] 3. In this invention, a movable airflow baffle is added. The movement of the airflow baffle is achieved by a computer and rollers. The purpose is to ensure sufficient gasification and avoid heat loss, so as to obtain a higher quality coal gas component. Attached Figure Description

[0040] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the structure of an underground coal gasification simulation device.

[0042] Figure 2 A schematic diagram of the internal structure of an underground coal gasification simulation device. Figure 1 .

[0043] Figure 3 A schematic diagram of the internal structure of an underground coal gasification simulation device. Figure 2 .

[0044] Figure 4 This is a reference diagram of thermocouple arrangement in an underground coal gasification simulation device.

[0045] Legend:

[0046] 1. Gasifier; 2. Jack; 3. Support plate; 4. Sample coal seam; 5. Gasification channel; 6. Inlet pipe; 7. Outlet pipe; 8. Thermocouple; 9. Gasifying agent generating assembly; 10. Water injection port; 11. Atomizing nozzle; 12. Ignition device; 13. Airflow baffle; 14. Roller; 15. Flow meter; 16. Compressible sealing ring; 17. Furnace cover; 18. Top plate; 19. Bottom plate; 20. Computer. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0048] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0049] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0050] In the description of the embodiments of the present invention, it should be noted that the terms "upper" and "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0051] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0052] Please see Figure 1-4 This invention provides a coal underground gasification simulation device, comprising:

[0053] A gasifier 1 is provided, which contains multiple jacks 2. Each jack 2 is supported by a bearing plate 3. A sample coal layer 4 is placed above the bearing plate 3. A gasification channel 5 is provided inside the sample coal layer 4. An inlet pipe 6 and an outlet pipe 7 are respectively provided at both ends of the gasification channel 5. Both the inlet pipe 6 and the outlet pipe 7 extend to the surface of the gasifier 1. Several thermocouples 8 are provided on both sides of the sample coal layer 4 and are connected to the gasifier 1.

[0054] A gasifying agent generating component 9 is connected to the gas inlet pipe 6 via a pipe for injecting gas into the gasifier 1.

[0055] A water supply assembly includes a water inlet 10 disposed in the gasifier 1, the water inlet 10 being connected to a plurality of atomizing nozzles 11 inside the gasifier 1, the atomizing nozzles 11 being located inside the gasification channel 5; each atomizing nozzle has an independent valve for control, and the atomizing nozzle is connected to the outside through the water inlet;

[0056] Ignition device 12, which is located near the bottom of the air inlet pipe 6, is used to ignite the sample coal seam 4.

[0057] The gasifying agent generating assembly 9 includes a nitrogen cylinder, an oxygen cylinder, and an air cylinder, each with a valve connected to the pipeline. The oxygen and air cylinders provide the oxygen needed for igniting the sample coal seam, while the nitrogen cylinder is used for fire extinguishing. The valves facilitate the opening and closing of the respective cylinders.

[0058] At least one airflow baffle 13 is provided inside the vaporization channel 5. The airflow baffle 13 is connected to a roller 14, which is movably connected inside the vaporization channel 5. The airflow baffle is connected to the roller by a rope, and the roller rotates to move a distance. The airflow baffle is made of refractory and heat-insulating high-alumina brick and has a certain weight. Based on the temperature measured by several thermocouples, a movable airflow baffle is set in the lower part of the vaporization channel. The thermocouple information is transmitted to the computer, and the computer controls the roller to move the position of the airflow baffle.

[0059] Both the air inlet pipe 6 and the air outlet pipe 7 are equipped with flow meters 15. The flow meters are water vapor vortex flow meters.

[0060] A compressible sealing ring 16 is provided between the support plate 3 and the gasifier 1. The compressible sealing ring is made of refractory material.

[0061] The gasifier 1 includes a gasifier body and a furnace cover 17, the furnace cover 17 being detachably connected to the gasifier body. A graphite sealing ring is provided between the furnace cover 17 and the gasifier body. The furnace cover is fixed to the upper part of the gasifier body by a clamping plate and the graphite sealing ring. The gasifier includes an insulation layer and a refractory layer.

[0062] The sample coal seam 4 is provided with a roof plate 18 at its upper part and a bottom plate 19 at its lower part. A topsoil layer is provided on the roof plate 18.

[0063] It also includes a computer 20, and the thermocouple 8, the jack 2, and the atomizing nozzle 11 are all connected to the computer 20 for control. This facilitates control and operation.

[0064] A simulation method for an underground coal gasification simulation device includes the following steps:

[0065] Step 1: Select the sample coal for the experiment, arrange the sample coal bed and gasification channel, and select the inclination angle for the experiment.

[0066] Select the experimental coal sample, then arrange the base plate. After arranging the experimental coal sample at the bottom of the gasification channel, select the desired tilt angle. The four jacks can intelligently adjust the required height. At the same time, compressible sealing rings are connected to both ends of the plate. The compressible sealing rings are in contact with the gasifier body. Under the squeezing action, the compressible sealing rings deform to maintain the sealing of the gasification process.

[0067] Step 2: Drill holes in the sample coal seam at the bottom of the gasification channel using an electric drill, and arrange several thermocouples. Connect the thermocouple signal lines to accurately identify the data measured by each thermocouple.

[0068] Step 3: Set up an airflow baffle, which is connected to a roller via a rope; the thermocouple feeds the temperature feedback to the computer, which processes the data to determine the moving distance, and the roller rotates to move the airflow baffle.

[0069] Twenty-five thermocouples are set up during the gasification process, nine of which are located at the bottom of the gasification channel. The thermocouples feed the temperature back to the computer, which processes the data to determine the moving distance. The rollers rotate to move the distance.

[0070] Step 4: Arrange the sample coal seam in the upper part of the gasification channel, drill holes using an electric drill, install several thermocouples and water injection pipes, and install atomizing nozzles in the upper part of the gasification channel;

[0071] Each atomizing nozzle has an independent valve, allowing for control of the water injection rate based on feedback from several thermocouples. This enables precise control of the oxidation (reduction) zone area, ensuring sufficient energy for the entire vaporization process. Each atomizing nozzle has nine injection ports, such as... Figure 3 As shown, fine and uniform particles are sprayed in all directions in a 360° pattern, with the atomizing nozzle as the center.

[0072] Step 5: Arrange the coal seam roof and topsoil, place water injection pipes on the upper part of the roof, and place the furnace cover and graphite sealing ring at the same time. The furnace cover is connected to the gasifier body by a clamp.

[0073] Step Six: The gasifying agent generating component charges gasifier 1, and then the ignition device is activated to ignite the sample coal seam.

[0074] Taking a specific thermocouple as an example, such as Figure 4 As shown, when the thermocouple temperature is 1200℃ or the gasification reaction in the oxidation zone is too fast, the atomizing nozzles near the thermocouple should be opened or enlarged appropriately. When the temperature is 1000℃ or the energy provided by the oxidation zone is insufficient to maintain the gasification reaction in the oxidation zone, the atomizing nozzles near the thermocouple should be reduced or even closed. This will allow for reasonable control of the oxidation zone and the acquisition of higher quality coal gas components.

[0075] Vortex flow meters enable comprehensive control of water vapor during the gasification process. Water vapor content significantly impacts the gasification process. Different coal grades have vastly different water vapor requirements; both excessive and insufficient water vapor can negatively affect the gasification process.

[0076] Working Principle: A gasification channel with a certain angle is set in the lower part of the sample coal body. Inlet and outlet pipes are provided on both sides of the gasification channel, penetrating the coal seam, roof, and topsoil. A steam vortex flow meter is installed outside the gasifier. An ignition device is installed at the lower part of the inlet pipe, and an atomizing nozzle is installed at the upper part of the gasification channel, connected to the outside via a water injection port. An airflow baffle is installed in the lower part of the gasification channel, its position changing due to the rotation of rollers. Four jacks are installed inside the gasifier, connected to a steel bearing plate. The pressure plate is pressurized... The shrinking sealing ring contacts the gasifier body to maintain a tight seal, ensuring the gasification process is airtight. A thermocouple is installed and fixed to the gasifier body, sealed by the sealing ring. The thermocouple is connected to a thermocouple signal line to transmit the measured temperature signal to the computer for subsequent control of the airflow baffle and atomizing nozzle. The gasifier body contains an insulation layer and a refractory layer, as well as top soil, a top plate, and a bottom plate, to ensure the smooth operation of the gasification process. The thermocouple and roller are connected to the computer via a signal line. The inlet and outlet pipes are connected to the gasifying agent generating component and the gas treatment device via flexible hoses, respectively.

[0077] The jack adjustment steps are as follows: determine the desired adjustment angle, input the command into the computer, and the four jacks intelligently adjust to the required height. The angle control is achieved by simulating geological conditions using the four jacks. Atomizing nozzles are installed at the top of the gasification channel. These nozzles have nine atomizing ports, allowing for 360° atomization. All nozzles are made of refractory material. The spraying process involves the following steps: identifying the oxidation and reduction zones based on thermocouple feedback; determining the nozzle position and size as needed; performing atomization spray; adjusting the spray volume according to temperature; a movable airflow baffle is installed in the lower part of the gasification channel. Thermocouple information is transmitted to the computer, which controls the rollers to move the baffle position; 19 thermocouples are fixedly connected to the gasifier body and sealed with graphite sealing rings. The thermocouples are connected to thermocouple wires and are used to test the temperature changes of the entire gasifier body during the experiment. The thermocouple signal lines transmit the temperature signals to the subsequent processing computer.

[0078] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A coal underground gasification simulation device, characterized in that, include: A gasifier is provided, which contains multiple jacks, each with a support plate. A sample coal layer is located above the support plate, and a gasification channel is provided within the sample coal layer. An inlet pipe and an outlet pipe are respectively provided at both ends of the gasification channel, and both the inlet pipe and the outlet pipe extend to the surface of the gasifier. Several thermocouples are provided on both sides of the sample coal layer and are connected to the gasifier. A gasifying agent generating assembly, which is connected to the gas inlet pipe via a pipeline for injecting gas into the gasifier; A water supply assembly, comprising a water injection port disposed in the gasifier, the water injection port being connected to a plurality of atomizing nozzles inside the gasifier, the atomizing nozzles being located in the upper middle part of the gasification channel; An ignition device is provided, located near the bottom of the air inlet pipe, for igniting the sample coal seam. At least one airflow baffle is provided in the vaporization channel, the airflow baffle is connected to a roller, and the roller is movably connected in the vaporization channel; It also includes a computer, and the thermocouple, the jack and the atomizing nozzle are all connected to the computer for control; the thermocouple feeds back the temperature to the computer, the computer processes the data to determine the moving distance, and the roller rotates to move the airflow baffle.

2. The underground coal gasification simulation device according to claim 1, characterized in that, The vaporizing agent generating assembly includes a nitrogen cylinder, an oxygen cylinder, and an air cylinder, and valves are provided between the nitrogen cylinder, the oxygen cylinder, and the air cylinder and the pipeline.

3. The underground coal gasification simulation device according to claim 1, characterized in that, Both the air inlet pipe and the air outlet pipe are equipped with flow meters.

4. The underground coal gasification simulation device according to claim 1, characterized in that, A compressible sealing ring is provided between the support plate and the gasifier.

5. The underground coal gasification simulation device according to claim 1, characterized in that, The gasifier includes a gasifier body and a furnace cover, the furnace cover being detachably connected to the gasifier body.

6. The underground coal gasification simulation device according to claim 5, characterized in that, A graphite sealing ring is provided between the furnace cover and the gasification furnace body.

7. The underground coal gasification simulation device according to claim 1, characterized in that, The sample coal seam is provided with a roof plate at the top and a bottom plate at the bottom, and a topsoil layer is provided on the roof plate.

8. The simulation method for an underground coal gasification simulation device according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Select the sample coal for the experiment, arrange the sample coal bed and gasification channel, and select the inclination angle for the experiment. Step 2: Drill holes in the sample coal seam at the bottom of the gasification channel using an electric drill, and arrange several thermocouples. Connect the thermocouple signal lines to accurately identify the data measured by each thermocouple. Step 3: Set up an airflow baffle, which is connected to a roller via a rope; the thermocouple feeds the temperature feedback to the computer, which processes the data to determine the moving distance, and the roller rotates to move the airflow baffle. Step 4: Arrange the sample coal seam in the upper part of the gasification channel, drill holes using an electric drill, install several thermocouples and water injection pipes, and install atomizing nozzles in the upper part of the gasification channel; Step 5: Arrange the coal seam roof and topsoil, place water injection pipes on the upper part of the roof, and place the furnace cover and graphite sealing ring at the same time. The furnace cover is connected to the gasifier body by a clamp. Step Six: The gasifying agent generating component charges the gasifier with gas, and then the ignition device is activated to ignite the sample coal seam.

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