A co-well jet injection and production device and its usage method

Abstract

The present invention relates to the technical field of injection-production engineering in oil and gas field development, and particularly relates to a jet injection-production device in the same well and a usage method thereof. The technical solution is as follows: A jet pump is connected to the surface wellhead through an oil pipe and a small-diameter oil pipe. A retrievable pump core is installed in the jet pump. The lower part is connected to a jet injection pump through an oil-blocking and water-filtering device. The outlet pipe of the mixed liquid is located in the water injection layer below the packer. A part of the high-pressure power liquid injected from the ground enters the jet pump and entrains and sucks the low-water-cut crude oil to the ground. The remaining high-pressure power liquid passes through the retrievable pump core in the jet pump and enters the jet injection pump, entrains and sucks the formation water that has been deoiled and filtered by the oil-blocking and water-filtering device and injects it into the water injection layer. The beneficial effects are as follows: The structure is simple, the failure rate is low, the operation is reliable, the pump inspection period is long, it is convenient for well washing and pump inspection, the investment and operation costs are saved, and it is more suitable for large-angle wells, infill wells in the middle and late stages of exploitation, multi-layer separate injection-production development in the high-water-cut period, and meets the essential requirements of energy conservation and consumption reduction.

Description

Technical Field

[0001] The present invention relates to the technical field of injection-production engineering in oil and gas field development, and particularly relates to a same-well jet production-injection device and a using method thereof. Background Art

[0002] For multi-layer reservoirs, in order to improve the production speed and efficiency, a same-well production-injection string is adopted, which can realize dual functions of injection and production in one well, effectively reduce the injection-production cost, and improve the production efficiency. The existing same-well injection-production process string, especially the same-well production-up and injection-down string, mostly consists of an underground double-stage submersible electric pump and an underground separator injection-production system, which requires a dedicated underground oil-water separation device to be configured. After the water content in the produced fluid is separated by cyclone and then injected into the same-well injection layer, its separation effect is difficult to be stable due to the restriction of the cyclone speed. The underground device has a complex structure, and it is difficult to coordinate the two sets of electric pump injection-production systems. Moreover, the double-stage submersible electric pump in the same well also has problems such as a complex string structure, high investment, high workover operation cost, and difficulty in adapting to the well conditions of underground corrosion, scaling, sand production, high gas-oil ratio, and large deviation. Summary of the Invention

[0003] The purpose of the present invention is to provide a same-well jet production-injection device and a using method thereof for the above-mentioned defects existing in the prior art. By adopting a double-stage jet pump of a jet oil production pump and a jet water injection pump, oil production in the upper layer and water injection in the lower layer of the same well are realized. It has a simple structure, low failure rate, reliable operation, long workover period, is convenient for well flushing and workover, reduces the liquid lifting and surface treatment workload, and saves investment and operation costs.

[0004] A same-well jet production-injection device mentioned in the present invention has the following technical solution: It includes a packer, and the packer is installed between the oil production layer and the water injection layer underground. Among them, it also includes a small-diameter oil pipe, a jet oil production pump, a jet water injection pump, and an oil-blocking and water-filtering device. The jet oil production pump is connected to the ground wellhead through an oil pipe and a small-diameter oil pipe. A retrievable pump core is installed in the jet oil production pump. The oil-blocking and water-filtering device is connected to the lower part of the jet oil production pump through an oil pipe, and the jet water injection pump is connected to the lower part of the oil-blocking and water-filtering device through an oil pipe. The mixed liquid outlet pipe of the jet water injection pump is located in the water injection layer below the packer. The high-pressure power liquid injected from the ground descends through the small-diameter oil pipe. A part of it enters the jet oil production pump and entrains and sucks the low-water-content crude oil in the annular space between the oil pipe and the casing, and then rises to the ground along the annular space between the oil pipe and the small-diameter oil pipe. The remaining high-pressure power liquid passes through the retrievable pump core in the jet oil production pump and the connected oil pipe below and continues to descend into the jet water injection pump, entrains and sucks the formation water filtered by the oil-blocking and water-filtering device. The formed mixed water is injected into the water injection layer together through the mixed liquid outlet pipe and the lower oil pipe, realizing same-well injection-production.

[0005] Preferably, the above jet pump is a double-tube positive-circulation jet pump, which includes a pump barrel, a nozzle section, a formation fluid inlet, a throat section, a retrievable pump core, a diffuser section, and a pump core seat. A formation fluid inlet is provided in the middle of the pump barrel and is connected to the throat section. The nozzle section is located above the throat section. The nozzle section is an annular structure formed by the retrievable pump core and the inner wall of the pump barrel. The lower part of the throat section is the diffuser section, and the lower end outlet of the diffuser section is connected to the mixed liquid outlet cavity. A pump core seat is installed at the lower part of the inner cavity of the pump barrel to support the retrievable pump core through the pump core seat. A lateral liquid inlet is provided at the top of the retrievable pump core.

[0006] Preferably, the above mixed liquid outlet cavity is an arc-shaped cavity structure located on the inner wall of the pump barrel and is not connected to the formation fluid inlet. The mixed liquid outlet cavity communicates upward along the outer wall of the pump barrel with the annulus formed by the inner tube and the outer tube, so that the mixed liquid continues to rise along the annulus of the tubing and the small-diameter tubing and is produced to the ground.

[0007] Preferably, the above retrievable pump core includes a pump core body, a fishing head, a conical adapter, an inclined liquid inlet, and a lateral liquid inlet. A fishing head is provided at the top of the pump core body, and a conical adapter is provided at the lower end. The conical adapter is connected and matched with the pump core seat. A plurality of lateral liquid inlets are provided in the upper part of the pump core body, and a plurality of inclined liquid inlets are provided on the lower side of the fishing head, so that the high-pressure power liquid is divided into two parts. One part is sprayed out along the annular structure formed by the retrievable pump core and the inner wall of the pump barrel, and the other part enters the inner cavity of the pump core body along the inclined liquid inlet and the lateral liquid inlet.

[0008] Preferably, the above jet injection pump is a downhole jet injection pump, which includes a pump body, an upper joint of the pump body, a retrievable nozzle, a throat, a power liquid inlet to the pump, a water intake, and a mixed liquid outlet. The upper end of the pump body is connected to the upper joint of the pump body. A power liquid inlet to the pump is provided at the top of the upper joint of the pump body, and the retrievable nozzle is installed in the inner cavity of the upper joint of the pump body. A water intake is provided on the upper side of the pump body, a throat is installed in the inner cavity of the pump body, a diffuser cavity is located below the throat, and a mixed liquid outlet is provided at the lower end of the pump body.

[0009] Preferably, a sealing ring is installed at the lower end of the above upper joint of the pump body, and a set screw is installed on the upper wall of the pump body. The pump body and the upper joint of the pump body are connected and locked through the set screw.

[0010] Preferably, the above retrievable nozzle includes a retrievable nozzle body, a nozzle fishing head, a nozzle liquid inlet, a nozzle body support part, and a nozzle. A nozzle fishing head is provided at the top of the retrievable nozzle body. The inner cavity of the retrievable nozzle body is a hollow structure, and a nozzle liquid inlet is provided on the lower side of the nozzle fishing head. The middle and lower part of the retrievable nozzle body is a conical nozzle body support part, which contacts the conical inner wall of the middle and lower part of the upper joint of the pump body to support the retrievable nozzle body. A nozzle is provided at the lower end of the retrievable nozzle body.

[0011] Preferably, the above oil-blocking and water-filtering device includes a central pipe, a central screen pipe, an upper protection ring, an upper fixing ring, a multi-layer water-filtering and oil-blocking elastic screen, an oil-blocking and water-filtering material, a lower fixing ring, a leather cup seal, and a diversion hole. The central pipe is installed inside the inner cavity of the central screen pipe. The oil-blocking and water-filtering material is installed on the outer wall of the central screen pipe. A multi-layer water-filtering and oil-blocking elastic screen is arranged outside the oil-blocking and water-filtering material. The lower ends of the oil-blocking and water-filtering material and the multi-layer water-filtering and oil-blocking elastic screen are fixed by the lower fixing ring, and the upper ends are fixed by the upper protection ring and the upper fixing ring. A leather cup seal is arranged on the lower side of the central screen pipe, and a diversion hole is arranged in the lower part of the central screen pipe.

[0012] Preferably, the outer diameter of the above central pipe is smaller than the inner diameter of the central screen pipe, and an annular space is formed between the central pipe and the central screen pipe. After the oil-water mixture passes through the multi-layer water-filtering and oil-blocking elastic screen and the oil-blocking and water-filtering material, it enters the annular space between the central pipe and the central screen pipe, and then flows out through the diversion hole, and then is injected into the injection layer through a jet injection water pump.

[0013] The usage method of the co-well jet injection-production device mentioned in the present invention includes the following processes:

[0014] (1) Lower the co-well jet injection-production device into the well. Start the surface high-pressure injection water pump. First, wash the well forward to clean the liquid stored in the wellbore, and then introduce it into the co-well jet injection-production process. The high-pressure power liquid descends along the small-diameter oil pipe and enters the jet oil extraction pump, and then aspirates the low-water-cut crude oil in the annular space between the oil pipe and the casing and rises to the surface along the annular space between the oil pipe and the small-diameter oil pipe; the remaining high-pressure power liquid passes through the retrievable pump core in the jet oil extraction pump and the oil pipe connected below and continues to descend into the jet injection water pump, aspirating the formation water filtered by the oil-blocking and water-filtering device. The formed mixed water is injected into the injection layer through the mixed liquid outlet pipe and the oil pipe below, realizing the functions of co-well oil production and water injection;

[0015] (2) When it is necessary to inspect and replace the jet oil extraction pump, lower a fishing tool connected by wire into the small-diameter oil pipe to lift out the retrievable pump core. After overhaul, lower the repaired retrievable pump core into the well from the small-diameter oil pipe to resume injection-production, without the need for workover equipment;

[0016] When it is necessary to replace and overhaul the retrievable nozzle in the lower jet injection water pump, first lift out the retrievable pump core in the jet oil extraction pump, and then lower a fishing tool connected by wire to fish out the retrievable nozzle of the jet injection water pump from the well for inspection and replacement. After overhaul, lower it into the well from the small-diameter oil pipe. The outer diameter of the retrievable pump core of the upper jet oil extraction pump is larger than the outer diameter of the retrievable nozzle of the lower jet injection water pump to ensure the smooth fishing up and down of the retrievable nozzle;

[0017] (3) Well flushing operation: After injecting and producing from the same well for a period of time, when it is necessary to clean the oil stains in the annular space between the tubing and the casing at the lower part of the wellbore and the outer wall of the oil-blocking and water-filtering device, and increase the cleanliness of the injected water, first stop injecting the high-pressure power fluid, close the annular wellhead gate of the small-diameter tubing and the surface wellhead, open the casing gate, then use the high-pressure backflow water from the injection layer to wash the oil stains on the inner wall of the annular space between the oil-blocking and water-filtering device, tubing and casing for reverse well flushing operation, and wash out the blockages and oil stains to the ground.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. The present invention uses a two-stage jet pump of a jet oil production pump and a jet water injection pump to realize oil production from the upper layer and water injection from the lower layer in the same well. Compared with the existing submersible electric pump and other injection and production systems, it has a simple structure, no relative moving parts, low failure rate, reliable operation, long pump inspection period, convenient well flushing and pump inspection, reduces the workload of liquid production lifting and surface treatment, saves investment and operation costs, realizes dual use of injection and production in one well, and is more suitable for large-angle wells, infill wells in the middle and late stages of exploitation, multi-layer separate injection and production development in the high water cut period, and meets the essential requirements of energy conservation and consumption reduction;

[0020] 2. The present invention utilizes the long-spacing oil casing annular space between the oil production layer and the water injection layer, and its high-temperature condition as an oil-water gravity separator, and uses a water-filtering and oil-blocking device as a fine oil remover for the injected water to assist in purifying the water quality. Compared with other downhole oil-water separators, it has a simple structure, good oil-water separation effect, reliable operation, energy conservation, environmental protection, and economic applicability;

[0021] 3. The annular jet oil production pump and the retrievable nozzle jet water injection pump of the present invention have a novel and convenient structure, can repair and replace the nozzles of the double pumps without moving the tubing string, are convenient for operation and management. The streamline-shaped flow channels inside greatly reduce the hydraulic friction resistance, ensure a high pump efficiency and good scale and corrosion inhibition effects. The tubing string structure of the present invention has the functions of reverse well flushing and self-cleaning oil-blocking and water-filtering device, and its operation is simple and the operation is reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the overall structural schematic diagram of the present invention;

[0023] Figure 2 is the structural schematic diagram of the jet oil production pump;

[0024] Figure 3 is Figure 2 the A-A cross-sectional schematic diagram of

[0025] Figure 4 is the structural schematic diagram of the retrievable pump core;

[0026] Figure 5 is the structural schematic diagram of the jet water injection pump;

[0027] Figure 6 It is a structural schematic diagram of a retrievable nozzle;

[0028] Figure 7 It is a structural schematic diagram of an oil-blocking and water-filtering device;

[0029] In the above figure: small-diameter oil pipe 1, oil pipe 2, jet oil production pump 3, jet water injection pump 4, oil-blocking and water-filtering device 5, packer 6, oil production layer 7, water injection layer 8, casing 9, pump barrel 3.1, nozzle section 3.2, formation fluid inlet 3.3, throat section 3.4, retrievable pump core 3.5, diffusion section 3.6, pump core seat 3.7, inner pipe 3.8, outer pipe 3.9, mixed liquid outlet cavity 3.10, pump core main body 3.5.1, fishing head 3.5.2, tapered adapter 3.5.3, inclined liquid inlet 3.5.4, lateral liquid inlet 3.5.5, pump body 4.1, upper joint of pump body 4.2, retrievable nozzle 4.3, throat 4.4, power liquid inlet to pump 4.5, water suction port 4.6, mixed liquid outlet 4.7, set screw 4.8, sealing ring 4.9, retrievable nozzle main body 4.3.1, nozzle fishing head 4.3.2, nozzle liquid inlet 4.3.3, nozzle main body support part 4.3.4, nozzle 4.3.5, central pipe 5.1, central screen pipe 5.2, tubing collar 5.3, upper protection ring 5.4, upper fixing ring 5.5, multi-layer water-filtering and oil-blocking elastic screen 5.6, oil-blocking and water-filtering filter material 5.7, lower fixing ring 5.8, cup seal 5.9, diversion hole 5.10. Specific embodiments

[0030] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0031] Example 1, referring to Figures 1 - 7, a simultaneous injection and production device with jet flow in the same well mentioned in the present invention includes a packer 6, and the packer 6 is installed between an oil production layer 7 and a water injection layer 8 underground. Among them, it further includes a small-diameter oil pipe 1, a jet pump 3, a jet water injection pump 4, and an oil-blocking and water-filtering device 5. The jet pump 3 is connected to the ground wellhead through an oil pipe 2 and the small-diameter oil pipe 1. A retrievable pump core 3.5 is installed in the jet pump 3. The oil-blocking and water-filtering device 5 is connected to the lower part of the jet pump 3 through the oil pipe 2, and the jet water injection pump 4 is connected to the lower part of the oil-blocking and water-filtering device 5 through the oil pipe 2. The mixed liquid outlet pipe of the jet water injection pump 4 is located in the water injection layer 8 below the packer 6; the high-pressure power liquid injected from the ground descends through the small-diameter oil pipe 1. A part of it enters the jet pump 3 and entrains and sucks the low-water-cut crude oil in the annular space between the oil pipe 2 and the casing 9, and then rises to the ground along the annular space between the oil pipe 2 and the small-diameter oil pipe 1; the remaining high-pressure power liquid passes through the retrievable pump core 3.5 in the jet pump 3 and the connected oil pipe 2 below and continues to descend into the jet water injection pump 4, entrains and sucks the formation water after being deoiled and filtered by the oil-blocking and water-filtering device 5. The formed mixed water is injected into the water injection layer 8 together through the mixed liquid outlet pipe and the oil pipe 2 below, realizing simultaneous injection and production in the same well.

[0032] Refer to Figures 2 - 4 , the jet pump 3 mentioned in the present invention adopts a double-pipe positive-circulation jet pump, which includes a pump barrel 3.1, a nozzle section 3.2, a formation liquid inlet 3.3, a throat section 3.4, a retrievable pump core 3.5, a diffuser section 3.6, and a pump core seat 3.7. A formation liquid inlet 3.3 is provided in the middle of the pump barrel 3.1 and is connected to the throat section 3.4. The nozzle section 3.2 is located above the throat section 3.4. The nozzle section 3.2 is an annular structure formed by the retrievable pump core 3.5 and the inner wall of the pump barrel 3.1. The lower part of the throat section 3.4 is the diffuser section 3.6, and the lower end outlet of the diffuser section 3.6 is connected to the mixed liquid outlet cavity 3.10; a pump core seat 3.7 is installed in the lower part of the inner cavity of the pump barrel 3.1 to support the retrievable pump core 3.5 through the pump core seat 3.7, and a lateral liquid inlet 3.5.5 is provided at the top of the retrievable pump core 3.5.

[0033] Among them, the above-mentioned mixed liquid outlet cavity 3.10 is an arc-shaped cavity structure, located on the inner wall of the pump barrel 3.1 and not connected to the formation liquid inlet 3.3. The mixed liquid outlet cavity 3.10 is connected to the annulus formed by the inner pipe 3.8 and the outer pipe 3.9 upward along the outer wall of the pump barrel 3.1, so that the mixed liquid continues to rise along the annulus between the oil pipe 2 and the small-diameter oil pipe 1 and is produced to the ground.

[0034] Refer to Figure 4, the retrievable pump core 3.5 mentioned in the present invention includes a pump core main body 3.5.1, a fishing head 3.5.2, a conical adapter 3.5.3, an inclined liquid inlet 3.5.4, and a lateral liquid inlet 3.5.5. A fishing head 3.5.2 is provided at the top of the pump core main body 3.5.1, and a conical adapter 3.5.3 is provided at the lower end, which is cooperatively connected with the pump core seat 3.7 through the conical adapter 3.5.3; a plurality of lateral liquid inlets 3.5.5 are provided in the upper part of the pump core main body 3.5.1, and a plurality of inclined liquid inlets 3.5.4 are provided on the lower side of the fishing head 3.5.2, so that the high-pressure power liquid is divided into two parts. One part sprays out along the annular structure formed between the retrievable pump core 3.5 and the inner wall of the pump barrel 3.1, and the other part enters the inner cavity of the pump core main body 3.5.1 along the inclined liquid inlet 3.5.4 and the lateral liquid inlet 3.5.5.

[0035] Refer to Figure 5 , the jet injection pump 4 mentioned in the present invention adopts a downhole jet injection pump. The downhole jet injection pump includes a pump body 4.1, an upper joint of the pump body 4.2, a retrievable nozzle 4.3, a throat pipe 4.4, a power liquid inlet to the pump 4.5, a water suction port 4.6, and a mixed liquid outlet 4.7. The upper end of the pump body 4.1 is connected to the upper joint of the pump body 4.2. A power liquid inlet to the pump 4.5 is provided at the top of the upper joint of the pump body 4.2, and a retrievable nozzle 4.3 is installed in the inner cavity of the upper joint of the pump body 4.2; a water suction port 4.6 is provided on the upper side of the pump body 4.1, a throat pipe 4.4 is installed in the inner cavity of the pump body 4.1, the lower side of the throat pipe 4.4 is a diffuser cavity, and a mixed liquid outlet 4.7 is provided at the lower end of the pump body 4.1.

[0036] Among them, a sealing ring 4.9 is installed at the lower end of the above-mentioned upper joint of the pump body 4.2, and a set screw 4.8 is installed on the upper wall of the pump body 4.1. The pump body 4.1 and the upper joint of the pump body 4.2 are connected and locked through the set screw 4.8.

[0037] Refer to Figure 6 , the retrievable nozzle 4.3 mentioned in the present invention includes a retrievable nozzle main body 4.3.1, a nozzle fishing head 4.3.2, a nozzle liquid inlet 4.3.3, a nozzle main body support part 4.3.4, and a nozzle 4.3.5. A nozzle fishing head 4.3.2 is provided at the top of the retrievable nozzle main body 4.3.1. The inner cavity of the retrievable nozzle main body 4.3.1 is a hollow structure, and a nozzle liquid inlet 4.3.3 is provided on the lower side of the nozzle fishing head 4.3.2. The middle and lower part of the retrievable nozzle main body 4.3.1 is a conical nozzle main body support part 4.3.4, which contacts the conical inner wall of the middle and lower part of the upper joint of the pump body 4.2 to support the retrievable nozzle main body 4.3.1; a nozzle 4.3.5 is provided at the lower end of the retrievable nozzle main body 4.3.1.

[0038] Refer to Figure 7, the oil-blocking and water-filtering device 5 mentioned in the present invention includes a central pipe 5.1, a central screen pipe 5.2, a tubing coupling 5.3, an upper guard ring 5.4, an upper fixing ring 5.5, a multi-layer water-filtering and oil-blocking elastic screen 5.6, an oil-blocking and water-filtering material 5.7, a lower fixing ring 5.8, a leather cup seal 5.9, and a diversion hole 5.10. The central pipe 5.1 is installed in the inner cavity of the central screen pipe 5.2. The oil-blocking and water-filtering material 5.7 is installed on the outer wall of the central screen pipe 5.2. A multi-layer water-filtering and oil-blocking elastic screen 5.6 is arranged outside the oil-blocking and water-filtering material 5.7. The lower ends of the oil-blocking and water-filtering material 5.7 and the multi-layer water-filtering and oil-blocking elastic screen 5.6 are fixed by the lower fixing ring 5.8, and the upper ends are fixed by the upper guard ring 5.4 and the upper fixing ring 5.5. A leather cup seal 5.9 is arranged on the lower side of the central screen pipe 5.2, and a diversion hole 5.10 is arranged at the lower part of the central screen pipe 5.2. The top of the central screen pipe 5.2 is connected to the upper tubing 2 through the tubing coupling 5.3.

[0039] Among them, the outer diameter of the central pipe 5.1 is smaller than the inner diameter of the central screen pipe 5.2, and an annulus is formed between the central pipe 5.1 and the central screen pipe 5.2. After the oil-water mixture passes through the multi-layer water-filtering and oil-blocking elastic screen 5.6 and the oil-blocking and water-filtering material 5.7, it enters the annulus between the central pipe 5.1 and the central screen pipe 5.2, and then flows out through the diversion hole 5.10, and then is injected into the water injection layer 8 through the jet injection water pump 4.

[0040] The usage method of the co-well jet injection-production device mentioned in the present invention includes the following processes:

[0041] (1) Lower the co-well jet injection-production device into the well. Start the surface high-pressure injection water pump. First, wash the well forward to clean the liquid stored in the wellbore, and then introduce it into the co-well jet injection-production process. The high-pressure power liquid descends through the small-diameter tubing 1 and enters the jet pump 3, and then aspirates the low-water-cut crude oil in the annular space between the tubing 2 and the casing 9, and then rises to the ground along the annular space between the tubing 2 and the small-diameter tubing 1; the remaining high-pressure power liquid passes through the retrievable pump core 3.5 in the jet pump 3 and the connected tubing 2 below and continues to descend into the jet injection water pump 4, aspirating the formation water filtered by the oil-blocking and water-filtering device 5. The formed mixed water is injected into the water injection layer 8 together through the mixed liquid outlet pipe and the lower tubing 2, realizing the functions of co-well oil production and water injection;

[0042] (2) When it is necessary to check and replace the jet pump 3, lower a fishing tool connected by wire into the small-diameter tubing 1 to lift out the retrievable pump core 3.5. After maintenance, put the repaired retrievable pump core 3.5 into the well from the small-diameter tubing 1 to resume injection-production, without the need for workover equipment;

[0043] When it is necessary to replace and overhaul the retrievable nozzle 4.3 in the lower jet injection pump 4, first lift out the retrievable pump core 3.5 in the jet oil extraction pump 3, and then lower a fishing tool connected by wire to fish out the retrievable nozzle 4.3 of the jet injection pump 4 for in-well maintenance and replacement. After the maintenance, it is put into the well through the small-diameter tubing 1. The outer diameter of the retrievable pump core 3.5 of the upper jet oil extraction pump 3 is larger than the outer diameter of the retrievable nozzle 4.3 of the lower jet injection pump 4 to ensure the smooth lifting and lowering of the retrievable nozzle 4.3.

[0044] (3) Well flushing operation: After injecting and producing in the same well for a period of time, when it is necessary to clean the oil stain on the outer wall of the annular space between the tubing 2 and the casing 9 at the lower part of the wellbore and the oil-blocking and water-filtering device 5 and increase the cleanliness of the injected water, first stop injecting the high-pressure power fluid and close the annulus wellhead gate of the small-diameter tubing 1 and the surface wellhead, and open the casing gate. Then, use the high-pressure backflow water of the injection layer 8 to wash the oil stain on the inner wall of the annular space between the oil-blocking and water-filtering device 5, the tubing 2 and the casing 9 for reverse well flushing operation, and wash out the blockage and oil stain to the ground.

[0045] The above are only some preferred embodiments of the present invention. Any person skilled in the art may modify the above-described technical solutions or modify them into equivalent technical solutions. Therefore, the corresponding simple modifications or equivalent transformations made according to the technical solutions of the present invention all fall within the scope of protection required by the present invention.

Claims

1. A jet injection and production device in the same well, comprising a packer (6), the packer (6) is installed between an oil production layer (7) and a water injection layer (8) underground, and is characterized in that: It also includes a small-diameter oil pipe (1), a jet pump (3), a jet water injection pump (4) and an oil-blocking and water-filtering device (5). The jet pump (3) is connected to the ground wellhead through an oil pipe (2) and the small-diameter oil pipe (1). A retrievable pump core (3.5) is installed in the jet pump (3). The oil-blocking and water-filtering device (5) is connected to the lower part of the jet pump (3) through the oil pipe (2), and the jet water injection pump (4) is connected to the lower part of the oil-blocking and water-filtering device (5) through the oil pipe (2). The mixed liquid outlet pipe of the jet water injection pump (4) is located in the water injection layer (8) below the packer (6). The high-pressure power liquid injected from the ground descends through the small-diameter oil pipe (1). A part of it enters the jet pump (3) and entrains and sucks the low-water-cut crude oil in the annular space between the oil pipe (2) and the casing (9), and then rises to the ground along the annular space between the oil pipe (2) and the small-diameter oil pipe (1). The remaining high-pressure power liquid passes through the retrievable pump core (3.5) in the jet pump (3) and the connected oil pipe (2) below and continues to descend into the jet water injection pump (4), entrains and sucks the formation water after oil removal and filtration by the oil-blocking and water-filtering device (5). The formed mixed water is injected into the water injection layer (8) together through the mixed liquid outlet pipe and the oil pipe (2) below, realizing simultaneous injection and production in the same well.

2. The co-well jet injection and production device according to claim 1, characterized in that: The jet pump (3) adopts a double-pipe positive-circulation jet pump, which includes a pump barrel (3.1), a nozzle section (3.2), a formation fluid inlet (3.3), a throat section (3.4), a retrievable pump core (3.5), a diffuser section (3.6), and a pump core seat (3.7). A formation fluid inlet (3.3) is provided in the middle of the pump barrel (3.1) and is connected to the throat section (3.4). The nozzle section (3.2) is located above the throat section (3.4). The nozzle section (3.2) is an annular structure formed by the retrievable pump core (3.5) and the inner wall of the pump barrel (3.1). The lower part of the throat section (3.4) is the diffuser section (3.6), and the lower end outlet of the diffuser section (3.6) is connected to the mixed liquid outlet cavity (3.10). A pump core seat (3.7) is installed in the lower part of the inner cavity of the pump barrel (3.1) to support the retrievable pump core (3.5) through the pump core seat (3.7), and a lateral liquid inlet (3.5.5) is provided at the top of the retrievable pump core (3.5).

3. The co-well jet injection and production device according to claim 2, characterized in that: The mixed liquid outlet cavity (3.10) is an arc-shaped cavity structure, located on the inner wall of the pump barrel (3.1) and not connected to the formation fluid inlet (3.3). The mixed liquid outlet cavity (3.10) is connected to the annulus formed by the inner pipe (3.8) and the outer pipe (3.9) upward along the outer wall of the pump barrel (3.1), so that the mixed liquid continues to rise along the annulus between the oil pipe (2) and the small-diameter oil pipe (1) and is produced to the ground.

4. The co-well jet injection and production device according to claim 3, characterized in that: The retrievable pump core (3.5) includes a pump core body (3.5.1), a fishing head (3.5.2), a conical socket joint (3.5.3), an inclined liquid inlet (3.5.4), and a lateral liquid inlet (3.5.5). The fishing head (3.5.2) is provided at the top of the pump core body (3.5.1), and the conical socket joint (3.5.3) is provided at the lower end. The conical socket joint (3.5.3) is cooperatively connected with the pump core seat (3.7). A plurality of lateral liquid inlets (3.5.5) are provided in the upper part of the pump core body (3.5.1), and a plurality of inclined liquid inlets (3.5.4) are provided on the lower side of the fishing head (3.5.2), so that the high-pressure power liquid is divided into two parts. One part is ejected along the annular structure formed by the retrievable pump core (3.5) and the inner wall of the pump barrel (3.1), and the other part enters the inner cavity of the pump core body (3.5.1) along the inclined liquid inlet (3.5.4) and the lateral liquid inlet (3.5.5).

5. The co-well jet injection and production device according to claim 4, characterized in that: The jet injection pump (4) adopts a downhole jet injection pump, which includes a pump body (4.1), a pump body upper joint (4.2), a retrievable nozzle (4.3), a throat tube (4.4), a power liquid inlet to the pump (4.5), a water inlet (4.6), and a mixed liquid outlet (4.7). The upper end of the pump body (4.1) is connected to the pump body upper joint (4.2). The power liquid inlet to the pump (4.5) is provided at the top of the pump body upper joint (4.2), and the retrievable nozzle (4.3) is installed in the inner cavity of the pump body upper joint (4.2). The water inlet (4.6) is provided on the upper side of the pump body (4.1), the throat tube (4.4) is installed in the inner cavity of the pump body (4.1), the lower side of the throat tube (4.4) is a diffuser cavity, and the mixed liquid outlet (4.7) is provided at the lower end of the pump body (4.1).

6. The co-well jet injection and production device according to claim 5, characterized in that: A sealing ring (4.9) is installed at the lower end of the pump body upper joint (4.2), and a set screw (4.8) is installed on the upper wall of the pump body (4.1). The pump body (4.1) and the pump body upper joint (4.2) are connected and locked by the set screw (4.8).

7. The same-well jet injection and production device according to claim 6, characterized in that: The retrievable nozzle (4.3) includes a retrievable nozzle body (4.3.1), a nozzle fishing head (4.3.2), a nozzle liquid inlet (4.3.3), a nozzle body support part (4.3.4), and a nozzle (4.3.5). The nozzle fishing head (4.3.2) is provided at the top of the retrievable nozzle body (4.3.1). The inner cavity of the retrievable nozzle body (4.3.1) is a hollow structure, and the nozzle liquid inlet (4.3.3) is provided on the lower side of the nozzle fishing head (4.3.2). The middle and lower part of the retrievable nozzle body (4.3.1) is a conical nozzle body support part (4.3.4), which contacts the conical inner wall of the middle and lower part of the pump body upper joint (4.2) to support the retrievable nozzle body (4.3.1). The nozzle (4.3.5) is provided at the lower end of the retrievable nozzle body (4.3.1).

8. The same-well jet injection and production device according to claim 7, characterized in that: The oil-blocking and water-filtering device (5) includes a central pipe (5.1), a central screen pipe (5.2), an upper retaining ring (5.4), an upper fixing ring (5.5), a multi-layer water-filtering and oil-blocking elastic screen (5.6), an oil-blocking and water-filtering material (5.7), a lower fixing ring (5.8), a leather cup seal (5.9), and a diversion hole (5.10). The central pipe (5.1) is installed in the inner cavity of the central screen pipe (5.2). The oil-blocking and water-filtering material (5.7) is installed on the outer wall of the central screen pipe (5.2). A multi-layer water-filtering and oil-blocking elastic screen (5.6) is arranged outside the oil-blocking and water-filtering material (5.7). The lower ends of the oil-blocking and water-filtering material (5.7) and the multi-layer water-filtering and oil-blocking elastic screen (5.6) are fixed by the lower fixing ring (5.8), and the upper ends are fixed by the upper retaining ring (5.4) and the upper fixing ring (5.5). A leather cup seal (5.9) is arranged on the lower side of the central screen pipe (5.2), and a diversion hole (5.10) is arranged at the lower part of the central screen pipe (5.2).

9. The co-well jet injection and production device according to claim 8, characterized in that: The outer diameter of the central pipe (5.1) is smaller than the inner diameter of the central screen pipe (5.2), and an annulus is formed between the central pipe (5.1) and the central screen pipe (5.2). The oil-water mixture passes through the multi-layer water-filtering and oil-blocking elastic screen (5.6) and the oil-blocking and water-filtering material (5.7) and then enters the annulus between the central pipe (5.1) and the central screen pipe (5.2), and then flows out through the diversion hole (5.10), and then is injected into the water injection layer (8) through the jet injection water pump (4).

10. The method for using the co-well jet injection and production device according to claim 9, characterized in that: It includes the following processes: (1) Lower the co-well jet injection-production device into the well. Start the surface high-pressure injection water pump. First, wash the well forward to clean the liquid stored in the wellbore, and then introduce it into the co-well jet injection-production process. The high-pressure power fluid descends through the small-diameter oil pipe (1) and enters the jet pump (3), and then aspirates the low-water-cut crude oil in the annular space between the suction pipe (2) and the casing (9), and then rises to the surface along the annular space between the oil pipe (2) and the small-diameter oil pipe (1); the remaining high-pressure power fluid passes through the retrievable pump core (3.5) in the jet pump (3) and the connected oil pipe (2) below and continues to descend into the jet injection water pump (4), aspirating the formation water filtered by the oil-blocking and water-filtering device (5). The formed mixed water is injected into the water injection layer (8) together through the mixed liquid outlet pipe and the oil pipe (2) below, realizing the functions of co-well oil production and water injection; (2) When it is necessary to inspect and replace the jet pump (3), lower a fishing tool connected by wire into the small-diameter oil pipe (1) to lift out the retrievable pump core (3.5). After maintenance, lower the repaired retrievable pump core (3.5) into the well from the small-diameter oil pipe (1) to resume injection-production, without the need for workover equipment; When it is necessary to replace and overhaul the retrievable nozzle (4.3) inside the lower jet injection pump (4), first lift out the retrievable pump core (3.5) inside the jet oil production pump (3), and then lower a wire-connected fishing tool to fish out the retrievable nozzle (4.3) of the jet injection pump (4) from the well for overhaul and replacement. After the overhaul, it is put into the well from the small-diameter oil pipe (1). The outer diameter of the retrievable pump core (3.5) of the upper jet oil production pump (3) is larger than the outer diameter of the retrievable nozzle (4.3) of the lower jet injection pump (4) to ensure the smooth tripping of the retrievable nozzle (4.3). (III) Well flushing operation: After co-injection and production in the same well for a period of time, when it is necessary to clean the oil stains in the annular space between the lower oil pipe (2) and the casing (9) of the wellbore and the outer wall of the oil-blocking and water-filtering device (5) and increase the cleanliness of the injected water, first stop injecting the high-pressure power fluid and close the annulus wellhead gate of the small-diameter oil pipe (1) and the surface wellhead, and open the casing gate. Then, use the high-pressure backflow water from the injection layer (8) to wash the oil stains on the inner wall of the annular space between the oil-blocking and water-filtering device (5), the oil pipe (2), and the casing (9) for reverse well flushing operation to wash out the blockages and oil stains to the ground.

Images