Steam-water separation device for gas pressure test of water-rich coal seam and use method thereof

Abstract

This invention belongs to the field of coal seam gas pressure testing technology, specifically relating to a steam-water separation device and its usage method for testing gas pressure in water-rich coal seams. It includes a separator layer within a tank, with a circular opening at the bottom center of the separator layer, and a hollow float on the circular opening. An end cap is detachably connected to the upper end of an upper water storage tank, connected to a water inlet pipe. A second circular opening is provided in the lower water storage tank, with another hollow float on the second circular opening. An outlet is formed on the outside of the second circular opening. Usage method: During pressure measurement, the interface is connected to the steam-water separation device. Gas enters the upper water storage tank, preferentially filling it. Water suspended by the first hollow float enters the lower water storage tank, where the second hollow float remains suspended, and water is discharged to the outside. This invention utilizes the different forces exerted by steam and water on the hollow float to achieve steam-water separation, eliminating the influence of coal seam water and meeting the requirements for precise direct measurement of gas pressure.

Description

Technical Field

[0001] This invention belongs to the field of coal seam gas pressure testing technology, specifically relating to a steam-water separation device and its usage method for testing gas pressure in water-rich coal seams. Background Technology

[0002] Coal seam gas pressure refers to the stress exerted on the coal face by a methane-based gas present in the pores and fractures of the coal seam during its free thermal motion. The original coal seam gas pressure before mining, gas extraction, and pressure relief is a crucial indicator for gas disaster prevention and control. Furthermore, coal seam gas pressure serves as a basis for predicting the risk of coal and gas outbursts, a prerequisite for implementing safety prevention measures in coal mines, and a foundation for ensuring safe mine production. Therefore, accurately measuring coal seam gas pressure is of paramount importance.

[0003] Currently, the most common method for measuring coal seam gas pressure in coal mines is the relatively mature borehole pressure measurement method. This method involves drilling a hole into the coal seam in a rock or coal roadway, followed by grouting and sealing the hole for pressure measurement, or using a capsule sealer. Although this borehole pressure measurement technology is relatively mature in my country, the success rate remains low due to the influence of various factors such as complex gas occurrence and geological structure. Sometimes, the surrounding rock of the coal seam is rich in water, or there is an aquifer in the nearby roof, which often allows water to rush into the pressure measurement borehole chamber through rock fissures, affecting the accuracy of the pressure measurement. When the water inflow is significant, the borehole pressure measurement is generally considered a failure. Therefore, based on existing borehole pressure measurement technology, how to accurately measure the true and effective coal seam gas pressure in water-rich coal seams is one of the important research topics at present. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a steam-water separation device for testing gas pressure in water-rich coal seams. This device utilizes the different forces exerted by steam and water on a hollow float to achieve steam-water separation, thereby eliminating the influence of coal seam water without leaking gas and meeting the requirement for precise direct measurement of gas pressure.

[0005] The specific technical solution adopted is as follows:

[0006] A steam-water separation device for testing gas pressure in water-rich coal seams includes a housing with a partition layer inside, dividing the housing into an upper water storage tank and a lower water storage tank. A circular opening (first) is located at the bottom center of the partition layer, connecting the upper and lower water storage tanks. A hollow float (first) is detachably attached to the upper surface of the circular opening (first). An end cap is detachably connected to the upper end of the upper water storage tank, and an inlet pipe is connected to the upper end of the end cap. A second circular opening (second) is located at the bottom of the lower water storage tank, and a second hollow float (second) is detachably attached to the upper surface of the second circular opening. An outlet is formed outside the housing from the second circular opening (second).

[0007] Furthermore, the upper section of the water storage tank is equipped with an upper section filter screen at the upper end of its interior, and the lower section of the water storage tank is equipped with a lower section filter screen at the upper end of its interior.

[0008] Furthermore, the box is provided with a rubber sealing ring one and a rubber sealing ring two; the rubber sealing ring one is sealed and fitted onto the circular opening one, and the rubber sealing ring two is sealed and fitted onto the circular opening two.

[0009] Furthermore, the upper water storage tank is detachably connected to the lower water storage tank.

[0010] Furthermore, a U-shaped cavity is formed at the bottom of the lower water storage tank, and a circular opening is located at the lower end of the U-shaped cavity, offset from the bottommost position.

[0011] Furthermore, a forked connection port is provided on the upper side of the water outlet. The forked connection port is formed by extending in the direction of the two water levels from a circular opening. A gas detector is connected to the forked connection port through a connecting pipe.

[0012] Furthermore, the diameter of the first hollow buoy is larger than the diameter of the first circular opening; the diameter of the second hollow buoy is larger than the diameter of the second circular opening; and the density of the first hollow buoy and the second hollow buoy is less than that of water.

[0013] Furthermore, the separating layer has a downward-curved structure; the bottom of the hollow float 2 is provided with a support block at an angle.

[0014] Furthermore, the upper outer surface of the upper section of the water storage tank is threadedly connected to the end cap; the upper end of the end cap is connected to the water inlet pipe through the water inlet nut.

[0015] A method of using a steam-water separation device for gas pressure testing in water-rich coal seams includes the following steps:

[0016] Step 1: After completing normal drilling, lowering the pressure testing pipe, and sealing the borehole in the coal seam requiring pressure testing, install a pressure testing pipe valve on the pressure testing pipe. The pressure testing pipe valve is connected to the pressure gauge and the water inlet pipe of the steam-water separator through an interface. Install pressure gauge valves and steam-water separator valves at the connection points of the pressure gauge and the steam-water separator, respectively. Set the steam-water separator vertically. Before starting the pressure test, close the steam-water separator valve; open the steam-water separator valve when the pressure gauge begins to display a value.

[0017] Step 2: The gas containing coal seam water is connected to the gas-water separator through the interface. The gas containing water flows into the upper water storage tank through the water inlet pipe. At this time, hollow float one is attached to circular opening one, and hollow float two is attached to circular opening two.

[0018] Step 3: When the water-containing gas flows into the upper water storage tank through the inlet pipe, the water-containing gas flows to the bottom of the partition layer as a water vapor mixture. The water flowing into the bottom of the partition layer causes the hollow float to rise, and the gas is retained in the upper part of the upper water storage tank.

[0019] Step 4: When the water level inside the upper water tank rises to a level that allows hollow float one to leave circular opening one, hollow float one floats up under the action of water. Some water flows into the lower water tank through circular opening one. The subsequent inflow of gas increases the gas pressure and water flow velocity, causing hollow float one to sink. When the gas content increases to a level that allows hollow float one to adhere to circular opening one, hollow float one and rubber sealing ring one adhere to each other inside the upper water tank, forming a sealed environment and achieving gas-water separation. When hollow float one floats up, hollow float two floats up under the action of water flow. Water flows out from the outlet to the outside. When hollow float one adheres to rubber sealing ring one, hollow float two sinks and adheres to rubber sealing ring two, achieving gas-water separation.

[0020] Step 5: During the separation process, the gas detector monitors the device.

[0021] The beneficial effects of this invention are:

[0022] This invention discloses a steam-water separation device for testing the gas pressure of water-rich coal seams. During underground coal seam gas pressure measurement, gas containing coal seam water enters the upper water storage tank through the steam-water separation device. Due to gravity, the water preferentially fills the upper water storage tank, causing a hollow float (1) located at the center of the tank to suspend. Water then enters the lower water storage tank, where a hollow float (2) also suspends. The water naturally drains to the outside, and the buoys, after falling, form a seal, preventing gas leakage. By utilizing the different forces exerted by steam and water on the hollow floats, steam-water separation is achieved, thus eliminating the influence of water in the coal seam without gas leakage. This meets the requirement of precise direct measurement of gas pressure, obtaining the true coal seam gas pressure. This has significant practical implications, scientifically and effectively addressing the influence of coal seam water on gas pressure. The steam-water separation device and measurement method are highly practical and have broad application value. Attached Figure Description

[0023] Figure 1 This is a cross-sectional structural schematic diagram of a steam-water separation device for testing gas pressure in water-rich coal seams according to the present invention.

[0024] Figure 2 This is a top view schematic diagram of a steam-water separation device for testing gas pressure in water-rich coal seams according to the present invention.

[0025] Figure 3 This is a schematic diagram of the structure of the steam-water separation device for testing gas pressure in a water-rich coal seam according to the present invention when no gas is introduced.

[0026] Figure 4 This is a schematic diagram of the gas-water separation device for testing gas pressure in water-rich coal seams according to the present invention when gas is introduced.

[0027] The components include: 1. Water inlet pipe; 2. Water inlet nut; 3. End cap; 4. Upper water storage tank; 5. Lower water storage tank; 6. Upper tank filter screen; 7. Hollow float one; 8. Rubber sealing ring one; 9. Lower tank filter screen; 10. Hollow float two; 11. Rubber sealing ring two; 12. Water outlet; 13. Gas detector; 14. Tank body; 15. Connecting pipe; 16. T-junction; 17. Pressure gauge valve. Detailed Implementation

[0028] To better explain and facilitate understanding of the present invention, the technical solution and effects of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] like Figures 1 to 4 As shown, this embodiment provides a steam-water separation device for testing the gas pressure of water-rich coal seams, including a housing 14. A partition layer is formed inside the housing 14, and the partition layer has a downward-facing arc-shaped structure. The partition layer divides the housing 14 into an upper water storage tank 4 and a lower water storage tank 5. A circular opening is provided at the bottom center of the partition layer, connecting the upper water storage tank 4 and the lower water storage tank 5. A hollow float 7 is detachably attached to the upper surface of the circular opening. The hollow float 7 can be in a fitted or detached state with the circular opening. The diameter of the hollow float 7 is larger than the diameter of the circular opening, ensuring that the hollow float 7 will not fall through the circular opening into the lower water storage tank 5, thus achieving a sealing effect. An end cap 3 is threadedly connected to the upper outer surface of the upper water storage tank 4. The end cap 3 can be removed from the upper water storage tank 4. The end cap 3 is connected to the inlet water pipe 1 via the inlet nut 2. The two ends of the end cap 3 serve as connecting ends for different structures, and have tubular structures with different diameters. The gas containing coal seam water enters the device's housing 14 through the inlet water pipe 1. A U-shaped cavity is formed at the bottom of the lower water storage tank 5. A circular opening 2 is provided at the lower end of the U-shaped cavity, offset from the lowest point, to facilitate horizontal connection of the circular opening 2. A hollow float 2 10 can be separably attached to the upper surface of the circular opening 2. A support block is provided at the bottom of the hollow float 2 10 at an angle to effectively attach the hollow float 2 10 to the circular opening 2, so that the hollow float 2 10 can be in a fitted state and a separated state with the circular opening 2. The diameter of the hollow float 2 10 is larger than the diameter of the circular opening 2, ensuring that the hollow float 2 10 can be attached to the circular opening 2, thus playing a sealing role.

[0030] In addition, the density of hollow float 7 and hollow float 10 is less than that of water. When water accumulates continuously on circular opening 1 or circular opening 2, hollow float 7 or hollow float 10 can float. Circular opening 2 forms a water outlet 12 on the outside of the box 14. In this embodiment, the water outlet 12 is set downward along circular opening 2, and the separated water is discharged to the outside from the water outlet 12.

[0031] In addition, to improve the sealing effect, rubber sealing ring 18 and rubber sealing ring 21 are installed inside the tank 14; rubber sealing ring 18 is sealed and fitted on the circular opening 1, and hollow float 17 is fitted with rubber sealing ring 18 to form a sealed environment inside the upper water storage tank 4; rubber sealing ring 21 is sealed and fitted on the circular opening 2, and hollow float 210 is fitted with rubber sealing ring 21 to form a sealed environment inside the lower water storage tank 5.

[0032] In a preferred embodiment, the upper section of the water storage tank 4 is provided with an upper section filter screen 6, and the lower section of the water storage tank 5 is provided with a lower section filter screen 9. Solid impurities exist in the gas containing coal seam water. By setting up the upper section filter screen 6 and the lower section filter screen 9, the solid impurities are separated. Using two filters makes the filtration of solid impurities more precise and fine, preventing solid impurities from clogging the path of the hollow float and causing it to malfunction.

[0033] In addition, to facilitate internal inspection and maintenance of the tank 14, the upper water storage tank 4 is detachably connected to the lower water storage tank 5. In this embodiment, the upper water storage tank 4 and the lower water storage tank 5 are connected by threads. When the device needs to be disassembled for inspection and maintenance, the internal inspection and maintenance of the tank 14 can be achieved by removing the end cover 3 and the upper water storage tank 4.

[0034] In a preferred embodiment, a forked connection port is provided on the upper side of the outlet 12, extending horizontally from the second circular opening. The forked connection port is connected to a gas detector 13 via a connecting pipe 15. The horizontal extension facilitates gas detection. The gas detector 13 will detect the liquid flowing out of the outlet 12. If there is a leak inside the upper water storage tank 4, the lower water storage tank 5 will act as a gas-water separator to ensure real-time monitoring of gas pressure. If there is a leak inside both the upper and lower tanks, the gas detector 13 will detect the gas and alarm for the abnormal signal, indicating that the device has completely failed and ensuring timely repair and replacement of the device.

[0035] The specific steps for using the above-mentioned steam-water separation device for testing gas pressure in water-rich coal seams are as follows:

[0036] Step 1: After completing normal drilling, lowering the pressure testing pipe, and sealing the borehole in the coal seam requiring pressure testing, install a pressure testing pipe valve on the pressure testing pipe. The pressure testing pipe valve (not shown in the figure) is connected to a tee connector 16. The tee connector 16 is connected to the pressure gauge and the water inlet pipe 1 of the steam-water separator. Install a pressure gauge valve 17 and a steam-water separator valve (not shown in the figure) at the connection points of the pressure gauge and the steam-water separator, respectively. Hang the steam-water separator vertically beside the pressure testing borehole. Before starting the pressure test, close the steam-water separator valve. Open the valve when the pressure gauge starts displaying a value of 0.1. The coal seam water inside the borehole will automatically be discharged through the steam-water separator, thus preserving the gas pressure inside the borehole.

[0037] Step 2: The coal seam water-containing gas is connected to the gas-water separator through the three-way interface 16. The gas containing coal seam water in the pressure measuring tube during normal pressure measurement is connected to the gas-water separator. The water-containing gas flows into the upper water storage tank 4 through the water inlet pipe 1. At this time, the hollow float 1 7 is attached to the circular opening 1, and the hollow float 2 10 is attached to the circular opening 2.

[0038] Step 3: When the water-containing gas flows into the upper water storage tank 4 through the inlet pipe 1, inlet nut 2, and end cap 3, some solid impurities in the water-containing gas are filtered by the upper tank filter screen 6. The water-containing gas, as a water vapor mixture, flows to the bottom of the partition layer due to gravity. When the water flowing into the bottom of the partition layer causes the hollow float 7 to float, the gas is retained in the upper part of the upper water storage tank 4.

[0039] Step 4: When the water level inside the upper water storage tank 4 rises to a certain level, the hollow float 7 will move away from the circular opening 1. The hollow float 7 will float under the action of water, and some water will flow into the lower water storage tank 5 through the circular opening 1. As gas flows in, the gas pressure increases, which increases the flow velocity of the water flowing into the lower water storage tank 5, causing the hollow float 7 to sink. When the gas content increases to a certain level, the hollow float 7 will come into contact with the circular opening 1. The hollow float 7 and the rubber sealing ring 8 will then be in contact inside the upper water storage tank 4 to form a sealed environment, thus achieving gas-water separation. Similarly, when the hollow float 7 floats, the hollow float 10 floats under the action of water flow, and the water flows out to the outside from the outlet 12. When the hollow float 7 comes into contact with the rubber sealing ring 8, the hollow float 10 sinks and comes into contact with the rubber sealing ring 11, achieving gas-water separation.

[0040] Step 5: During the gas-water separation process, the gas detector 13 monitors the device. When there is a leak in the housing 14, the gas detector 13 will alarm on the abnormal signal.

[0041] Working principle of this device: This invention connects to a steam-water separator via a three-way interface 16 during pressure measurement. During normal pressure measurement, coal seam water and methane gas are present in the measuring tube. The methane gas containing coal seam water enters the upper water storage tank 4 through the steam-water separator. Due to gravity, water preferentially fills the upper water storage tank 4, causing the hollow float 7 at the center of tank 14 to suspend. Water enters the lower water storage tank 5, where the hollow float 10 also suspends, naturally draining the water. When the coal seam water and methane gas inside the inlet pipe 1 are about to be exhausted, the hollow float 7 at the center of the upper water storage tank 4 naturally falls, forming a seal with the rubber sealing ring 8 at the bottom of the upper water storage tank 4. The gas pressure also creates a downward pressure, thus achieving a complete seal. The lower water storage tank 5 similarly forms a seal, achieving the purpose of removing coal seam water without leaking methane gas, thereby accurately measuring the true and effective coal seam methane pressure.

Claims

1. A steam-water separation device for testing gas pressure in water-rich coal seams, characterized in that: The device includes a housing with a partition layer inside, dividing the housing into an upper water storage tank and a lower water storage tank. A circular opening (first) is located at the bottom center of the partition layer, connecting the upper and lower water storage tanks. A hollow float (first) is detachably attached to the upper surface of the circular opening (first). An end cap is detachably connected to the upper end of the upper water storage tank, and a water inlet pipe is connected to the upper end of the end cap. A second circular opening (second) is located at the bottom of the lower water storage tank, and a second hollow float (second) is detachably attached to the upper surface of the second circular opening (second). A water outlet is formed outside the second circular opening (second). The upper water storage tank is detachably connected to the lower water storage tank; A forked connection port is provided on the upper side of the water outlet, extending horizontally from the second circular opening. The forked connection port is connected to a gas detector via a connecting pipe. The horizontal extension facilitates gas detection. The gas detector will detect the liquid flowing out of the water outlet. If there is a leak inside the upper water storage tank, the lower water storage tank will act as a gas-liquid separator to ensure real-time monitoring of gas pressure. If there is a leak inside both the upper and lower tanks, the gas detector will detect the gas and trigger an alarm for the abnormal signal.

2. The steam-water separation device for gas pressure testing in water-rich coal seams according to claim 1, characterized in that: The upper section of the water storage tank is equipped with an upper section filter screen at the upper end of its interior, and the lower section of the water storage tank is equipped with a lower section filter screen at the upper end of its interior.

3. The steam-water separation device for gas pressure testing in water-rich coal seams according to claim 1, characterized in that: The box is equipped with a rubber sealing ring one and a rubber sealing ring two; the rubber sealing ring one is sealed and fitted onto the circular opening one, and the rubber sealing ring two is sealed and fitted onto the circular opening two.

4. The steam-water separation device for gas pressure testing in water-rich coal seams according to claim 1, characterized in that: The bottom of the lower water storage tank has a U-shaped cavity, and the second circular opening is located at the lower end of the U-shaped cavity, offset from the bottommost position.

5. The steam-water separation device for gas pressure testing in water-rich coal seams according to claim 1, characterized in that: The diameter of the first hollow buoy is larger than the diameter of the first circular opening; the diameter of the second hollow buoy is larger than the diameter of the second circular opening; the density of the first hollow buoy and the second hollow buoy is less than that of water.

6. The steam-water separation device for gas pressure testing in water-rich coal seams according to claim 1, characterized in that: The separating layer has a downward-curved structure; the bottom of the hollow float 2 is provided with a support block at an angle.

7. The steam-water separation device for gas pressure testing in water-rich coal seams according to claim 1, characterized in that: The upper outer surface of the upper water storage tank is threadedly connected to the end cap; the upper end of the end cap is connected to the inlet water pipe through the inlet nut.

8. A method of using the steam-water separation device for gas pressure testing in water-rich coal seams as described in any one of claims 1-7, characterized in that: Includes the following steps: Step 1: After completing normal drilling, lowering the pressure testing pipe, and sealing the borehole in the coal seam requiring pressure testing, install a pressure testing pipe valve on the pressure testing pipe. The pressure testing pipe valve is connected to the pressure gauge and the water inlet pipe of the steam-water separator through an interface. Install pressure gauge valves and steam-water separator valves at the connection points of the pressure gauge and the steam-water separator, respectively. Set the steam-water separator vertically. Before starting the pressure test, close the steam-water separator valve; open the steam-water separator valve when the pressure gauge begins to display a value. Step 2: The gas containing coal seam water is connected to the gas-water separator through the interface. The gas containing water flows into the upper water storage tank through the water inlet pipe. At this time, hollow float one is attached to circular opening one, and hollow float two is attached to circular opening two. Step 3: When the water-containing gas flows into the upper water storage tank through the inlet pipe, the water-containing gas flows to the bottom of the partition layer as a water vapor mixture. The water flowing into the bottom of the partition layer causes the hollow float to rise, and the gas is retained in the upper part of the upper water storage tank. Step 4: When the water level inside the upper water tank rises to a level that allows hollow float one to leave circular opening one, hollow float one floats up under the action of water. Some water flows into the lower water tank through circular opening one. The subsequent inflow of gas increases the gas pressure and water flow velocity, causing hollow float one to sink. When the gas content increases to a level that allows hollow float one to adhere to circular opening one, hollow float one and rubber sealing ring one adhere to each other inside the upper water tank, forming a sealed environment and achieving gas-water separation. When hollow float one floats up, hollow float two floats up under the action of water flow. Water flows out from the outlet to the outside. When hollow float one adheres to rubber sealing ring one, hollow float two sinks and adheres to rubber sealing ring two, achieving gas-water separation. Step 5: During the separation process, the gas detector monitors the device.

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