Device and method for testing and evaluating health degree of sand-carrying jet pump for sand production well

Abstract

The invention discloses a sand-carrying jet pump health degree test evaluation device and method for a sand production well. The test evaluation device comprises a power liquid supply mechanism, a sand-containing liquid supply mechanism and a solid-liquid separation mechanism, wherein the power liquid supply mechanism and the sand-containing liquid supply mechanism are communicated with an inlet of a sand-carrying jet pump tool, and the solid-liquid separation mechanism is communicated with an outlet of the sand-carrying jet pump tool. The evaluation method comprises the following steps: simulating actual underground pressure and flow through the power liquid supply mechanism to output high-pressure power liquid; sand-containing fluid is supplied to the sand-carrying jet pump tool through the sand-containing fluid supply mechanism; the fluid mixed by the sand-carrying jet pump tool is output to the solid-liquid separation mechanism, and the liquid flows to the power liquid supply mechanism and the sand-containing liquid supply mechanism for recycling after passing through the solid-liquid separation mechanism; after continuous testing, the erosion wear degree of the throat pipe is measured, the wall thickness reduction of the throat pipe is obtained, and then the change trend of the health degree of the jet pump is obtained. The method can effectively predict the operation condition of the jet pump, guarantees the continuous production of an offshore jet pump production well, and improves the operation time rate of the oil well.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas exploitation, and particularly relates to a health test evaluation device and evaluation method for a sand-carrying jet pump used in sand-producing wells. Background Art

[0002] As a lifting method with strong adaptability, the jet pump plays an important role in the lifting of offshore oilfields. However, the operation of the jet pump depends on the continuous conversion of high-pressure power fluid energy. During the energy conversion process, the fluid will continuously wear the nozzle, resulting in an increase in the inner diameter of the nozzle and a decrease in the pump efficiency. However, after the nozzle wears to a certain extent, the operating parameters of the pump are quite different from the actual design parameters, and the pump failure rate increases accordingly.

[0003] There is no fault prediction method for existing jet pump production wells in the offshore area. Only the method of replacing the pump after a fault can be used for maintenance, which not only reduces the production time rate of oil wells but also wastes energy due to the long-term inefficient production of the pump. Therefore, an effective evaluation method for predicting the health of jet pumps in offshore production wells is of great significance for maintaining production efficiency and improving operation efficiency. Summary of the Invention

[0004] The present invention is proposed to solve the problems existing in the prior art, and its purpose is to provide a health test evaluation device and evaluation method for a sand-carrying jet pump used in sand-producing wells.

[0005] The present invention is achieved by the following technical solutions:

[0006] A health test evaluation device for a sand-carrying jet pump used in sand-producing wells includes a power fluid supply mechanism and a sand-containing fluid supply mechanism respectively connected to the inlet of the sand-carrying jet pump tooling, and a solid-liquid separation mechanism connected to the outlet of the sand-carrying jet pump tooling; the power fluid supply mechanism includes a water tank, a No. I centrifugal pump, and a No. I throttle valve connected in sequence through a high-pressure pipeline; the sand-containing fluid supply mechanism includes a sand supply box and a sand-liquid mixing device connected to each other; the solid-liquid separation mechanism includes a filter tank and a No. II centrifugal pump connected to each other through a high-pressure pipeline, and the outlet of the No. II centrifugal pump is respectively connected to a No. II throttle valve and a No. III throttle valve through a high-pressure pipeline; the outlet end of the No. II throttle valve is connected to the water tank, and the outlet end of the No. III throttle valve is connected to the sand-liquid mixing device.

[0007] In the above technical solution, the power fluid supply mechanism further includes a No. I flowmeter, and the No. I flowmeter is arranged between the No. I centrifugal pump and the No. I throttle valve.

[0008] In the above technical solution, the sand-containing fluid supply mechanism further includes a No. II flowmeter, and the No. II flowmeter is arranged on the pipeline at the outlet section of the sand-liquid mixing device.

[0009] In the above technical solution, a filter screen is arranged inside the filter tank; the connection between the filter tank and the outlet of the sand-carrying jet pump tooling is arranged above the filter screen; the connection between the filter tank and the No. II centrifugal pump is arranged below the filter screen.

[0010] A method for evaluating the health degree of a sand-carrying jet pump for a sand-producing well includes the following steps:

[0011] S1. Open all throttle valves in the test evaluation device, and simulate the actual downhole pressure and flow rate through the centrifugal pump of the power fluid supply mechanism to output high-pressure power fluid;

[0012] S2. Open the sand-liquid mixing device in the sand-containing liquid supply mechanism, mix and stir the sand conveyed by the sand supply box and the water conveyed by the solid-liquid separation mechanism, and the mixed and stirred fluid enters the sand-carrying jet pump tooling;

[0013] S3. The fluid mixed by the sand-carrying jet pump tooling is output to the solid-liquid separation mechanism. After passing through the solid-liquid separation mechanism, the liquid flows to the power fluid supply mechanism and the sand-containing liquid supply mechanism for recycling;

[0014] S4. Test a set of nozzle and throat combinations under fixed power fluid pressure, power fluid flow rate, and sand-containing liquid flow rate;

[0015] S5. After 1 day of sand washing test with the sand-containing liquid, close the device, take out the nozzle and throat in the sand-carrying jet pump tooling, measure the erosion and wear degree of the throat, obtain the reduction amount of the throat wall thickness, and further obtain the health degree of the jet pump.

[0016] S6. Repeat steps S4 and S5, continuously test for N days, record the health degree of the jet pump every day, and linearly fit to predict the change trend of the jet pump health degree.

[0017] In the above technical solution, the sand content rate of the fluid after mixing and stirring in step S2 is adjusted as required.

[0018] In the above technical solution, the calculation formula for the health degree of the jet pump is:

[0019]

[0020] In the formula: H o is the health degree of the jet pump, dimensionless; S ch is the original wall thickness of the throat, with the unit of m; d c is the reduction amount of the throat wall thickness, with the unit of m.

[0021] In the above technical solution, the evaluation standard for the health degree of the jet pump is:

[0022] H o ≤0.01, the health degree evaluation is "excellent", and the operation state is good;

[0023] 0.04 > H o > 0.02, the health assessment is "good" and the operating status is relatively good;

[0024] 0.06 > H o ≥ 0.04, the health assessment is "medium" and requires real-time attention;

[0025] H o ≥ 0.06, the health assessment is "poor", and it is recommended to repair and replace in time.

[0026] The beneficial effects of the present invention are:

[0027] The present invention provides a health test and evaluation device and method for a sand-carrying jet pump for sand production wells, which can effectively predict the operating conditions of the jet pump, help oilfield workers understand the operating conditions of the jet pump, help workers make pre-plans in advance, find the direction of process optimization and improvement, reduce the operation waiting period, reduce the production suspension caused by pump failures, improve the effective operation period and stability of the jet pump, ensure the continuous production of offshore jet pump production wells to the greatest extent, improve the operation efficiency of oil wells, and provide technical support for increasing reserves and production in offshore oilfields. Brief Description of the Drawings

[0028] Figure 1 It is a schematic structural diagram of the health test and evaluation device for a sand-carrying jet pump for sand production wells of the present invention.

[0029] Among them:

[0030] 1. Power fluid supply mechanism; 11. Water tank; 12. No. I centrifugal pump; 13. No. I flowmeter; 14. No. I throttle valve;

[0031] 2. Sand-containing fluid supply mechanism; 21. Sand supply box; 22. Sand-liquid mixing device; 23. No. II flowmeter;

[0032] 3. Solid-liquid separation mechanism; 31. Filter tank; 32. No. II centrifugal pump; 33. No. II throttle valve; 34. No. III throttle valve;

[0033] 4. Sand-carrying jet pump tooling; 41. Nozzle; 42. Throat tube.

[0034] For those of ordinary skill in the art, without creative efforts, other relevant drawings can be obtained based on the above drawings. Detailed Embodiments

[0035] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be further described below with reference to the accompanying drawings of the specification and through specific embodiments.

[0036] Example 1

[0037] As Figure 1 shown, a health evaluation device for a sand-carrying jet pump in a sand-producing well includes a power fluid supply mechanism 1 and a sand-containing fluid supply mechanism 2 that are respectively connected to the inlet of the sand-carrying jet pump tooling 4, and a solid-liquid separation mechanism 3 that is connected to the outlet of the sand-carrying jet pump tooling 4;

[0038] The power fluid supply mechanism 1 includes a water tank 11, a No. I centrifugal pump 12, a No. I flowmeter 13, and a No. I throttle valve 14 that are connected in sequence through high-pressure pipelines;

[0039] The sand-containing fluid supply mechanism 2 includes a sand supply box 21, a sand-fluid mixing device 22, and a No. II flowmeter 23 that are connected to each other;

[0040] The sand-fluid mixing device 22 is a conventional mixing tank with a stirring function;

[0041] The connection method between the sand supply box 21 and the sand-fluid mixing device 22 can adopt any method that can realize sand transportation, such as a conveyor belt;

[0042] The solid-liquid separation mechanism 3 includes a filter tank 31 and a No. II centrifugal pump 32 that are connected to each other through high-pressure pipelines. The outlet of the No. II centrifugal pump 32 is respectively connected to a No. II throttle valve 33 and a No. III throttle valve 34 through high-pressure pipelines; the outlet end of the No. II throttle valve 33 is connected to the water tank 11, and the outlet end of the No. III throttle valve 34 is connected to the sand-fluid mixing device 22;

[0043] A filter screen is arranged inside the filter tank 31;

[0044] The connection between the filter tank 31 and the outlet of the sand-carrying jet pump tooling 4 is arranged above the filter screen; the connection between the filter tank 31 and the No. II centrifugal pump 32 is arranged below the filter screen;

[0045] The sand-carrying jet pump tooling 4 includes a nozzle 41 and a throat 42. There is a liquid inlet channel between the upper end of the nozzle 41 and the throat 42. The upper end of the nozzle 42 is connected to the power fluid supply mechanism, and the lower end of the throat 42 is connected to the solid-liquid separation mechanism.

[0046] The power fluid supply mechanism transports high-pressure power fluid to the sand-carrying jet pump tooling through high-pressure pipelines, mixes and absorbs the sand-containing fluid in the sand-containing fluid supply mechanism, and is connected to the solid-liquid separation mechanism. Through the filtration and separation of the solid-liquid separation mechanism, the liquid is circulated to test the wear of the jet pump throat under the erosion of the sand-containing fluid, judge the health of the jet pump, and then predict and guide the workover operation, providing technical guarantee for improving the recovery rate to the greatest extent.

[0047] Example 2

[0048] In late 2022, a jet pump was installed for lifting production in Well A of the offshore oilfield. In January 2023, the produced fluid of the well was tested and found to contain 0.05% sand. Nozzles and throat pipes of the same model as those in this well were selected to conduct a sand-carrying production health evaluation test.

[0049] Connect the sand-carrying jet pump health evaluation test device according to Example 1. The test steps are as follows:

[0050] S1. Open all throttle valves in the test evaluation device, and use the centrifugal pump in the power fluid supply mechanism to simulate the actual downhole pressure and flow rate to output high-pressure power fluid.

[0051] S2. Open the sand-liquid mixing device in the sand-containing liquid supply mechanism, mix and stir the sand transported by the sand supply box and the water transported by the solid-liquid separation mechanism. The fluid after mixing and stirring enters the sand-carrying jet pump tooling, and the sand content rate in the fluid is set to 0.05%.

[0052] S3. The fluid mixed by the sand-carrying jet pump tooling is output to the solid-liquid separation mechanism. After solid-liquid separation, the liquid flows to the power fluid supply mechanism and the sand-containing liquid supply mechanism for recycling.

[0053] S4. Test a set of nozzle and throat pipe combinations under fixed power fluid pressure, power fluid flow rate, and sand-containing liquid flow rate.

[0054] S5. After 1 day of sand washing test with the sand-containing liquid, turn off the device, take out the nozzles and throat pipes in the sand-carrying jet pump tooling, measure the erosion and wear degree of the throat pipe, obtain the reduction amount of the throat pipe wall thickness, and then obtain the health degree of the jet pump.

[0055] S6. Repeat steps S4 and S5, continuously test for 30 days, record the health degree of the jet pump every day, and linearly fit to predict the change trend of the jet pump health degree.

[0056] Combined with the jet pump health degree calculation formula, the health degree and fitting results for 30 days are as follows:

[0057] Table: Health degree test results for 30 days

[0058] Time / day Health level Time / day Health level Time / day Health level 1 0.000123 11 0.001387 21 0.002617 2 0.000204 12 0.001624 22 0.002714 3 0.000392 13 0.001631 23 0.002921 4 0.000579 14 0.001788 24 0.0029648 5 0.000595 15 0.001995 25 0.003175 6 0.000662 16 0.002132 26 0.003202 7 0.000959 17 0.002179 27 0.003529 8 0.001026 18 0.002196 28 0.003556 9 0.001149 19 0.002513 29 0.003683 10 0.00137 20 0.00259 30 0.00381

[0059] The linear fitting test results show the following relationship between the health degree and the production days

[0060] H 0 = 0.0001d + 0.00002

[0061] Where: H o is the health degree of the jet pump; d is the number of days.

[0062] Combined with the fitting results of health and production days, with a health threshold of 0.06, it is predicted that the jet pump in Well A needs to replace the nozzle and throat pipe after 599 days. To prevent overall failure of the jet pump caused by excessive wear of the nozzle and throat pipe, the nozzle and throat pipe components were replaced on-site 615 days after sand production in September 2024, and the reduction amount d of the throat pipe wall thickness was measured after removal. c It was 0.8 mm, and the health was 0.0625, which was basically consistent with the predicted results, effectively verifying the reliability of the evaluation device and evaluation method of this application.

[0063] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0064] The applicant declares that the above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and disclosure scope of the present invention.

Claims

1. A sand-carrying jet pump health test and evaluation device for a sand production well, characterized by: The invention comprises a power liquid supply mechanism (1) and a sand-containing liquid supply mechanism (2) respectively connected to the inlet of a sand-carrying jet pump tooling (4), and a solid-liquid separation mechanism (3) connected to the outlet of the sand-carrying jet pump tooling (4); the power liquid supply mechanism (1) comprises a water tank (11), a No. I centrifugal pump (12) and a No. I throttle valve (14) which are sequentially connected through a high-pressure pipeline; the sand-containing liquid supply mechanism (2) comprises a sand supply box (21) and a sand-liquid mixing device (22) which are connected to each other; the solid-liquid separation mechanism (3) comprises a filter tank (31) and a No. II centrifugal pump (32) which are connected to each other through a high-pressure pipeline, and the outlet of the No. II centrifugal pump (32) is respectively connected to the No. II throttle valve (33) and the No. III throttle valve (34) through the high-pressure pipeline; the outlet end of the No. II throttle valve (33) is connected to the water tank (11), and the outlet end of the No. III throttle valve (34) is connected to the sand-liquid mixing device (22).

2. The health test and evaluation device for a sand-carrying jet pump for a sand production well according to claim 1 is characterized in that: The power fluid supply mechanism (1) further comprises a No. I flow meter (13), wherein the No. I flow meter (13) is arranged between the No. I centrifugal pump (12) and the No. I throttle valve (14).

3. The health test and evaluation device for a sand-carrying jet pump for a sand production well according to claim 1, characterized in that: The sand-containing liquid supply mechanism (2) further comprises a No. II flow meter (23), and the No. II flow meter (23) is arranged on the pipeline of the outlet section of the sand-liquid mixing device (22).

4. The health test and evaluation device for a sand-carrying jet pump for a sand production well according to claim 1, characterized in that: A filter screen is arranged inside the filter tank (31); the connection between the filter tank (31) and the outlet of the sand-carrying jet pump tooling (4) is arranged above the filter screen; and the connection between the filter tank (31) and the No. II centrifugal pump (32) is arranged below the filter screen.

5. An evaluation method using the health test and evaluation device for a sand-carrying jet pump for a sand production well according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Open all throttle valves in the test evaluation device, and output high-pressure power fluid through the centrifugal pump of the power fluid supply mechanism to simulate the actual downhole pressure and flow; S2, open the sand-liquid mixing device in the sand-containing liquid supply mechanism, mix and stir the sand transported by the sand supply box and the water transported by the solid-liquid separation mechanism, and the mixed and stirred fluid enters the sand-carrying jet pump tooling; S3, the fluid mixed by the sand-carrying jet pump tooling is output to the solid-liquid separation mechanism, and after passing through the solid-liquid separation mechanism, the liquid flows to the power liquid supply mechanism and the sand-containing liquid supply mechanism for recycling; S4, a set of nozzles and throats are tested under fixed power fluid pressure, power fluid flow rate, and sand-containing fluid flow rate; S5. After one day of sand-containing liquid sand flushing test, the device is turned off, the nozzle and throat in the sand-carrying jet pump tooling are taken out, the degree of erosion and wear of the throat is measured, the reduction in throat wall thickness is obtained, and then the health of the jet pump is obtained. S6. Repeat steps S4 and S5, test continuously for N days, record the health of the jet pump every day, and use linear fitting to predict the change trend of the health of the jet pump.

6. The method for testing and evaluating the health of a sand-carrying jet pump for a sand production well according to claim 5, characterized in that: The sand content of the fluid after mixing and stirring in step S2 is adjusted as needed.

7. The method for testing and evaluating the health of a sand-carrying jet pump for a sand production well according to claim 5, characterized in that: The calculation formula of the jet pump health is: Where: H o is the health of the jet pump, dimensionless; S ch is the original wall thickness of the throat, in m; d c is the reduction in throat wall thickness, in m.

8. The method for testing and evaluating the health of a sand-carrying jet pump for a sand production well according to claim 5, characterized in that: The evaluation criteria for the health of the jet pump are: H o ≤0.01, the health evaluation is excellent; 0.04>H o >0.02, the health evaluation is good; 0.06>H o ≥0.04, health evaluation is medium; H o ≥0.06, the health evaluation is poor.

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