A gas-liquid-solid three-phase cyclone sand removal device
By designing a gas-liquid solid three-phase cyclone sand removal device, and using its own liquid flushing and automated control system, the high sand discharge frequency and safety hazards of traditional cyclone sand removal devices when dealing with liquid natural gas is solved, and a single The effect of continuous sand removal and reduction of project costs.
Patent Information
- Application Number
- CN202010239929.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2020-03-31
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2040-03-31
AI Technical Summary
When dealing with liquid natural gas, the traditional cyclone sand deduker has a high sand discharge frequency, requires external high-pressure water to flush, and is complex in operation, resulting in high engineering construction costs and safety hazards, and it is impossible to achieve a single continuous sand removal operation.
Design a gas-liquid solid three-phase cyclone sand removal device, including a cyclone separator, sand storage tank, shutdown valve, sand discharge valve, bypass pipe and flow limiter, and use the liquid in the bypass pipe for self-flushing , combine the level meter and PLC control system to achieve automatic sand discharge, ensuring continuous operation of a single device without external flushing water requirements.
The simultaneous separation of gas-liquid solid three-phase media is achieved, which reduces sand discharge frequency and engineering construction costs, reduces manual operations, ensures sand removal efficiency and safety, and avoids the use of external flushing water.
Smart Images
Figure CN111271045B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of sand removal devices, and in particular to a gas-liquid-solid three-phase cyclone sand removal device. Background Art
[0002] As the exploitation of natural gas fields in my country continues to deepen, the problem of sand production in gas wells in some areas, especially high-yield gas wells, has become increasingly serious, causing great harm to the ground gathering and processing systems. Installing a desander at the natural gas wellhead can effectively remove sand and gravel from the natural gas and protect downstream equipment well. However, due to the high wellhead pressure, complex media, and variable fluids, wellhead desanding is more difficult than desanding at gas gathering stations, metering stations, and transfer stations. Cyclone separation technology is widely used because of its simple equipment structure, small footprint, low cost, simple maintenance, low energy consumption, high efficiency, and environmental protection. It can flexibly, continuously, and reliably complete the separation task during the working process, and has a certain degree of automation and stability. Traditional cyclone desanders are usually only suitable for the separation of gas-solid and liquid-solid phases. When dealing with the task of desanding liquid natural gas, the frequency of sand discharge increases, resulting in an increase in workload. The treatment of a large amount of discharged liquid water is also a problem to be solved. In addition, a single traditional cyclone desander cannot perform continuous desanding operations. To ensure continuous desanding, two cyclone desanders are usually connected in parallel. When one cyclone desander is desanding, the other cyclone desander is turned on for desanding operations, which results in high engineering construction costs. At the same time, the sand discharge start-up time of the traditional cyclone desander needs to be calculated based on the water and sand content of the natural gas. When the water and sand content of the natural gas fluctuates greatly, the sand discharge start-up time cannot be accurately controlled. The sand discharge process requires the introduction of external high-pressure water to flush the sand storage tank. The sand discharge process requires manual operation. After the sand discharge is completed, the air in the sand storage tank is mixed with the natural gas injected in the subsequent separation process, causing safety hazards. Summary of the invention
[0003] The purpose of the present invention is to overcome the deficiencies in the above-mentioned prior art and to provide a cyclone sand removal device which can reduce the liquid water content in the discharged sand, does not require external supply of additional sand flushing water, and can perform sand removal operations continuously on a single unit.
[0004] To achieve the above object, the technical solution of the present invention is achieved as follows:
[0005] A gas-liquid-solid three-phase cyclone sand removal device comprises a cyclone separator, a vertical exhaust pipe and a horizontal liquid inlet pipe are passed through the top of the cyclone separator, a horizontal liquid discharge pipe is passed through the middle of the cyclone separator, the bottom port of the cyclone separator is connected with a sand storage tank through a shut-off valve, a bypass pipe is passed through the cyclone separator and the sand storage tank; a flow limiter is arranged on the bypass pipe; a sand discharge valve is arranged at the bottom port of the sand storage tank, and a level meter is vertically fixedly arranged on the sand storage tank.
[0006] Furthermore, the height of the cylindrical section of the cyclone separator is twice the height of the conical section.
[0007] Furthermore, the liquid discharge pipe is passed through the axis of the cyclone separator, and the pipe opening of the insertion end is vertically downward.
[0008] Furthermore, the bypass pipe is horizontally inserted into the axial position at one end of the cyclone separator and bent 90 degrees downward along the axis to be inserted into the conical section of the cyclone separator. The length of the bent vertical pipe section is 2 / 3 of the height of the conical section of the cyclone separator.
[0009] Furthermore, the shut-off valve and the sand discharge valve are both explosion-proof electrically controlled pneumatic ball valves.
[0010] Furthermore, the flow limiter is composed of a single-hole flow limiting orifice plate.
[0011] Furthermore, the level meter is composed of a vibrating material density meter.
[0012] Compared with the prior art, the present invention has the following beneficial effects:
[0013] 1. The present invention can achieve simultaneous separation of gas, liquid and solid three-phase media. While maintaining the advanced performance of conventional cyclone separators, a shut-off valve is added between the cyclone separator and the sand storage pipe, which can achieve pressure sand discharge without stopping production of a single device, thereby reducing engineering construction costs. A single device can achieve continuous sand removal of tight gas wells without stopping production or reducing pressure.
[0014] 2. The cylindrical section of the cyclone separator is equipped with a drain pipe, which can discharge the separated liquid in time and reduce the frequency of sand discharge. The drain pipe design extending to the axis of the cyclone separator reduces the content of solid sand particles in the discharged liquid, ensuring the sand removal efficiency of the cyclone sand removal device. The early discharge of liquid reduces the liquid content in the discharged sand and reduces the difficulty and cost of effluent treatment.
[0015] 3. A bypass pipe is connected between the cyclone separator and the sand storage pipe. When the sand is discharged, the liquid accumulated in the cyclone separator is introduced to flush the sand storage tank. A single-hole flow-limiting orifice plate is provided on the bypass pipe to control the flow of the introduced sand flushing water to ensure the stable operation of the device. The sand discharge process does not require additional external flushing water, which reduces the cost of engineering construction and improves work efficiency. The sand removal process does not require manual operation, reducing the amount of manual work.
[0016] 4. A level meter is installed on the sand storage tank to detect the medium level in the sand storage tank and cooperate with the control system to control the start and stop of the sand discharge process. During the sand discharge process, the internal pressure of the device is always kept greater than the atmospheric pressure to ensure that external air cannot enter the cyclone sand removal device and eliminate safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a structural schematic diagram of the present invention;
[0018] Figure 2 It is a schematic diagram of the top structure of the present invention.
[0019] Description of reference numerals:
[0020] 1-cyclone separator, 2-sand storage tank, 3-shut-off valve, 4-sand discharge valve, 5-bypass pipe, 6-flow restrictor, 7-level meter, 11-liquid inlet pipe, 12-exhaust pipe, 13-liquid discharge pipe. DETAILED DESCRIPTION
[0021] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.
[0022] like Figure 1 and Figure 2 As shown, a gas-liquid-solid three-phase cyclone sand removal device comprises a cyclone separator 1, a vertical exhaust pipe 12 and a horizontal liquid inlet pipe 11 are penetrated at the top of the cyclone separator 1, a liquid discharge pipe 13 is penetrated horizontally in the middle of the cyclone separator 1 to the axial position of the cyclone separator 1, the insertion end of the liquid discharge pipe 13 is vertically downward, the bottom port of the cyclone separator 1 is connected to the sand storage tank 2 through a shut-off valve 3, a bypass pipe 5 is penetrated between the cyclone separator 1 and the sand storage tank 2, the cylindrical section height of the cyclone separator 1 is twice the height of the conical section; the bypass pipe 5 is A flow limiter 6 is provided, and the bypass pipe 5 is horizontally inserted to the axial position at one end of the cyclone separator 1 and bent 90° downward along the axis and inserted into the conical section of the cyclone separator 1, and the length of the vertical pipe section after bending is 2 / 3 of the height of the conical section of the cyclone separator 1; a sand discharge valve 4 is provided at the bottom port of the sand storage tank 2, and a level meter 7 is vertically fixed on the sand storage tank 2, and the level meter 7 is composed of a vibrating material density meter; the shut-off valve 3 and the sand discharge valve 4 are both explosion-proof electrically controlled pneumatic ball valves; the flow limiter 6 is composed of a single-hole flow limiting orifice plate.
[0023] The process steps for the liquid-containing natural gas of the present invention are as follows: open the shut-off valve 3, close the sand discharge valve 4, and the cyclone separator 1 and the sand storage tank 2 are internally connected and have the same pressure, so that the liquid-containing natural gas to be treated enters the cyclone separator 1 from the liquid inlet pipe 11, so that the solid particles and liquid are separated from the gas, liquid and solid in the cyclone separator 1 by the action of centrifugal force and gravity, so that the solid and a small amount of liquid are settled from the shut-off valve 3 to the sand storage tank 2, and the clean gas natural gas is discharged from the exhaust pipe 12 at the top of the cyclone separator 1, so that the gas is phase-separated and transported out. The settled solids and liquids are continuously accumulated in the sand storage tank 2, with the solid phase at the bottom and the liquid phase at the top, and the liquid level will gradually rise to the discharge pipe 13 in the middle of the cyclone separator 1, so that the discharge pipe 13 continuously flows out the liquid phase, so that the liquid is phase-separated and transported out. At the same time, since the drain pipe 13 acts as a liquid level limiter, the liquid level will not continue to rise, ensuring that the cyclone flow field space of the cyclone separator 1 above the drain pipe 13 is not occupied, thus meeting the conditions for continuous cyclone separation.
[0024] The whole cyclone sand removal device can be controlled by the PLC system in conjunction with the level meter 7. The top conical section of the sand storage tank 2 is set to a high level, and the bottom conical section of the sand storage tank 2 is set to a low level to cooperate with the PLC control system to realize the automatic start and stop of the sand discharge process. Under normal operating conditions, the shut-off valve 3 is opened, the bottom sand discharge valve 4 is closed, the cyclone separator 1 is connected to the inside of the sand storage tank 2, the pressure is consistent, and the solid and liquid mixture swirled out settles into the sand storage tank 2. When the solid level of the sand storage tank 2 reaches the high set point, the online sand discharge condition is started, the shut-off valve 3 is closed, and the sand discharge valve 4 is opened. A small atmospheric pressure storage tank is usually set downstream of the sand discharge valve 4 pipeline. At this time, since the sand storage tank 2 is pressurized and the back pressure is atmospheric pressure, a pressure difference is formed, and the sand-water mixture in the sand storage tank 2 will be discharged downstream, realizing the phase separation and external transmission of the solid phase. The pressure in the sand storage tank 2 gradually decreases as the mixture is discharged. At this time, since the cyclone separator 1 and the sand storage tank 2 are connected through the bypass pipe 5 with the flow restrictor 6, the cyclone separator 1 will also form a continuous pressure difference with the sand storage tank 2, and due to the flow limiting effect of the flow restrictor 6, a continuous pressure difference can be formed. Therefore, the liquid in the cyclone separator 1 can be used as flushing water and continuously flow to the sand storage tank 2 through the bypass pipe 5. When the solid level in the sand storage tank 2 reaches the low set point, the online sand discharge condition is completed, the shut-off valve 3 automatically opens, the sand discharge valve 4 automatically closes, and the equipment returns to normal operating conditions.
[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims
1. A method for using a gas-liquid-solid three-phase cyclone sand removal device, the gas-liquid-solid three-phase cyclone sand removal device comprising a cyclone separator, a vertical exhaust pipe and a horizontal liquid inlet pipe are provided on the top of the cyclone separator, characterized in that: A horizontal liquid discharge pipe is provided in the middle of the cyclone separator, the bottom port of the cyclone separator is connected to the sand storage tank through a shut-off valve, and a bypass pipe is provided between the cyclone separator and the sand storage tank; a flow limiter is provided on the bypass pipe; a sand discharge valve is provided at the bottom port of the sand storage tank, and a level meter is vertically fixed on the sand storage tank; the bypass pipe is horizontally inserted to the axis position at one end of the cyclone separator and bent 90° downward along the axis and inserted into the conical section of the cyclone separator, and the length of the bent vertical pipe section is 2 / 3 of the height of the conical section of the cyclone separator; the use method comprises: when the solid level in the sand storage tank reaches the high set point, the online sand discharge condition Start, the shut-off valve is closed, the sand discharge valve is opened, and the sand-water mixture in the sand storage tank will be discharged downstream, realizing the phase separation and external transmission of the solid phase. The pressure in the sand storage tank will gradually decrease as the mixture is discharged. At this time, since the cyclone separator is connected to the sand storage tank through a bypass pipe with a flow limiter, the cyclone separator will also form a continuous pressure difference with the sand storage tank, and due to the flow limiting effect of the flow limiter, a continuous pressure difference can be formed. Therefore, the liquid in the cyclone separator can be used as flushing water and continuously flows to the sand storage tank through the bypass pipe. When the solid level in the sand storage tank reaches the low set point, the online sand discharge condition is completed, the shut-off valve is automatically opened, the sand discharge valve is automatically closed, and the equipment returns to normal operating conditions.
2. The method for using the gas-liquid-solid three-phase cyclone sand removal device according to claim 1, characterized in that: The height of the cylindrical section of the cyclone separator is twice the height of the conical section.
3. The method for using the gas-liquid-solid three-phase cyclone sand removal device according to claim 1, characterized in that: The liquid discharge pipe is passed through to the axis position of the cyclone separator, and the pipe opening of the insertion end is vertically downward.
4. The method for using the gas-liquid-solid three-phase cyclone sand removal device according to claim 1, characterized in that: The shut-off valve and the sand discharge valve are both explosion-proof electrically controlled pneumatic ball valves.
5. The method for using the gas-liquid-solid three-phase cyclone sand removal device according to claim 1, characterized in that: The flow restrictor is composed of a single-hole flow restricting orifice plate.
6. The method for using the gas-liquid-solid three-phase cyclone sand removal device according to claim 1, characterized in that: The level meter is composed of a vibrating material density meter.