Same-well layered injection and production device

Abstract

The utility model provides a same-well layered injection and production device which comprises a casing pipe and a layered injection and production mechanism arranged in the casing pipe, and the layered injection and production mechanism comprises a first oil pipe and a second oil pipe concentrically arranged in the first oil pipe; wherein an oil extraction channel allowing oil gas to flow is formed in the casing pipe, and a bridge type connector corresponding to the oil extraction channel is arranged on the side wall of the second oil pipe.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of oil and gas reservoir development, and particularly relates to a same-well separate layer injection and production device. BACKGROUND

[0002] At present, oil and gas reservoir development is all carried out according to a development mode of layer-by-layer evaluation from bottom to top, and due to the demand for well pattern matching, some single wells need long-term water / gas injection, which will result in that the oil and gas potential layer in the upper part of the water / gas injection layer cannot contribute to the production capacity in time, thereby seriously affecting the oilfield production.

[0003] At present, the research on the same-well separate layer injection and production technology in the industry is still in the embryonic stage, and the above problems can be well solved by using the oil production wellhead and downhole concentric pipe technology in cooperation and through the same-well separate layer injection and production technology.

[0004] Therefore, it is hoped in the field to provide a same-well separate layer injection and production device to simultaneously realize the technical effects of lower water / gas injection and upper oil / gas production. CONTENT OF THE UTILITY MODEL

[0005] The purpose of the present application is to provide a same-well separate layer injection and production device, which is a matching technology of integrated well completion process and can realize lower liquid / gas injection and upper oil / gas production, thereby forming a set of unique separate layer injection and production process technology.

[0006] According to the present application, a same-well separate layer injection and production device is provided, which comprises a casing pipe, and

[0007] A separate layer injection and production mechanism is arranged in the casing pipe, the separate layer injection and production mechanism comprises a first oil pipe, and a second oil pipe arranged concentrically in the first oil pipe;

[0008] Wherein, an oil production channel allowing oil and gas to flow is formed on the casing pipe, and a bridge joint corresponding to the oil production channel is arranged on the side wall of the second oil pipe.

[0009] In one embodiment, an annular chamber for injecting fluid downhole is formed between the first oil pipe and the second oil pipe.

[0010] In one embodiment, a pumping unit is arranged in the second oil pipe, and after the fluid is injected downhole through the annular chamber, the pumping unit can lift the upward returning oil and gas to the ground.

[0011] In one embodiment, a sealing sleeve is arranged on the top of the bridge joint, and the bottom of the second oil pipe is nested in the sealing sleeve.

[0012] In one embodiment, the same-well separate layer injection and production device further comprises an injection pipe arranged below the first oil pipe, and a pressure holding ball seat for plugging the injection pipe.

[0013] In one embodiment, the injection pipe comprises a first pipe body configured in the form of a hollow cone, and a second pipe body configured in the form of a hollow sleeve and arranged below the first pipe body, wherein the pressure containment ball seat is within the range of the second pipe body.

[0014] In one embodiment, a packer for setting the casing is sleeved outside the second pipe body.

[0015] In one embodiment, an injection valve for communicating with the annular cavity is arranged above the casing, and a production valve for communicating with the second tubing is arranged above the casing.

[0016] In one embodiment, the fluid comprises any one of gas and liquid.

[0017] Compared with the prior art, the utility model has the advantages that:

[0018] Firstly, the utility model is a complete set of well completion technology, which can realize injection of fluid and gas downward and production of oil and gas upward, thereby forming a set of unique separate layer injection and production technology.

[0019] Secondly, the device has the advantages that the pressure of fluid injection downward is not limited and the packer is easy to be unsealed, thereby effectively assisting efficient development of oil and gas reservoirs and having extremely important significance for promoting progress of oil production technology, and can be applied to other oil fields in China. BRIEF DESCRIPTION OF DRAWINGS

[0020] The utility model will be described in detail below in combination with the drawings, in which:

[0021] Figure 1 The structure of the separate layer injection and production device in the same well according to the utility model is schematically shown;

[0022] Figure 2 is Figure 1 a partial enlarged view.

[0023] In the drawings, the same components use the same reference signs. The drawings are not drawn according to the actual scale. DETAILED DESCRIPTION

[0024] In order to make the technical scheme and advantages of the present application clearer, the exemplary embodiments of the present application will be further described in detail below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than an exhaustive enumeration of all embodiments. And in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0025] In the description of the present application, it should be understood that the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features with "first", "second" can be explicitly or implicitly included one or more features.

[0026] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements.

[0027] For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] The present application will be further described below with reference to the drawings.

[0029] Figure 1 The structure of the same well layering injection and production device 100 according to the present application is schematically shown;

[0030] Figure 2 For Figure 1 the local enlarged view.

[0031] As Figures 1-2 shown, according to the first aspect of the present application, a same well layering injection and production device 100 is provided, mainly comprising a casing 10, and a layering injection and production mechanism arranged concentrically in the casing 10. Preferably, the layering injection and production mechanism comprises a first oil pipe 11 arranged in the longitudinal direction, and a second oil pipe 12 arranged concentrically in the first oil pipe 11.

[0032] In an embodiment of the present application, as Figure 2 shown, an oil production channel 101 is formed on the inner wall of the casing 10, and the oil production channel 101 allows the oil and gas to flow outward, to facilitate the subsequent oil production work.

[0033] Preferably, as Figure 2As shown, the bridge joint 121 is arranged on the side wall of the second oil pipe 12, and the bridge joint 121 is arranged corresponding to the oil production channel 101, in other words, the opening direction of the bridge joint 121 is radially aligned with the oil production channel 101, and thus the downhole oil and gas can smoothly pass through the oil production channel 101 and the bridge joint 121 into the second oil pipe 12, to facilitate the subsequent lifting oil production work.

[0034] According to the utility model, Figure 2 As shown, the oil pump 14 is arranged in the second oil pipe 12. Therefore, the oil and gas returned to the second oil pipe 12 through the bridge joint 121 can be smoothly lifted to the ground by the oil pump 14, thereby completing the oil production work.

[0035] In an embodiment of the utility model, as shown in Figure 2 The annular chamber 130 is formed between the first oil pipe 11 and the second oil pipe 12. Preferably, the bottom of the annular chamber 130 is communicated with the casing 10, and fluid can be injected downward through the annular chamber 130 to realize the working environment of down injection and up production.

[0036] In the utility model, the annular chamber 130 formed between the first oil pipe 11 and the second oil pipe 12 can inject fluid into the well, thereby smoothly filling the well to replace the oil and gas in the well, to allow the oil and gas to enter the second oil pipe 12 in turn through the oil production channel 101 and the bridge joint 121. From this, the returned oil and gas can be smoothly lifted to the ground by the oil pump 14, thereby completing the working content of down injection fluid and up production.

[0037] In an embodiment, as shown in Figure 2 The sealing sleeve 122 is arranged at the top of the bridge joint 121 in the first oil pipe 11. And the bottom of the second oil pipe 11 is formed with a necked portion, and the inner diameter of the sealing sleeve 122 is not less than the outer diameter of the necked portion, so that the second oil pipe 11 can be inserted into the sealing sleeve 122 to form a back insertion seal with the first oil pipe 11.

[0038] In this way, not only the sealing property of the annular chamber 130 formed between the first oil pipe 11 and the second oil pipe 12 is ensured, thereby ensuring that the fluid injected downward and the oil and gas collected upward can have independent channels, to improve the working efficiency and working quality of the device; the overall structural stability of the device is also improved, to further prolong the service life of the device.

[0039] In an embodiment, as shown in Figure 2As shown, the same-well separate layer injection-production device 100 further comprises an injection pipe arranged below the first oil pipe 11, and a pressure-holding ball seat 15 for plugging the injection pipe. Preferably, the pressure-holding ball seat 15 is fixed in the injection pipe before the casing 10 is lowered, so as to ensure that the pressure-holding ball seat 15 can be successfully opened after the sealing test is passed, thereby further ensuring the safety and stability of the downhole operation.

[0040] Preferably, the pressure-holding ball seat 15 is used in cooperation with a ball, and the pressure-holding ball seat 15 can be opened by ball pressing after the setting and sealing test of the packer 17 (to be described below) is completed.

[0041] In one embodiment of the present application, as shown in Figure 2 The injection pipe comprises a first pipe body 161 and a second pipe body 162 arranged below the first pipe body 161. Preferably, the first pipe body 161 is configured in a hollow cone form, so as to abut against the packer 17 to complete the downhole setting work, and the second pipe body 162 is configured in a hollow sleeve form, so as to install the packer 17 on the outer wall thereof.

[0042] Preferably, the pressure-holding ball seat 15 is within the range of the second pipe body 162, in other words, the pressure-holding ball seat 15 is fixedly installed inside the second pipe body 162, so as to effectively prevent the premature unsealing during the lowering process.

[0043] In one embodiment, as shown in Figure 2 The packer 17 is arranged outside the second pipe body 162. Preferably, when the device is lowered to the predetermined position, i.e., when the bridge joint 121 is radially aligned with the production channel 101, the annular chamber 130 formed between the first oil pipe 11 and the second oil pipe 12 is pressed, so as to cause the packer 17 to set the casing 10, thereby completing the downhole setting work.

[0044] In one embodiment, as shown in Figure 1 The injection valve 18 for communicating with the annular chamber 13 is arranged above the casing 10. Preferably, the injection valve 18 can be used to inject fluid (such as gas or liquid) into the downhole, thereby achieving the work of injecting fluid downward.

[0045] In one embodiment, as shown in Figure 1 The production valve 19 for communicating with the second oil pipe 12 is arranged above the casing 10. Preferably, the production valve 19 and the oil pump 14 can be used to lift the upflowing oil and gas to the ground, thereby completing the work of producing oil upward.

[0046] According to the second aspect of the present application, an injection-production process is provided, which utilizes the same-well separate layer injection-production device according to the above, and comprises the following steps:

[0047] First, determine the specific gravity of the well killing fluid, pipe scraping, and well washing;

[0048] Then, the first tubing 11 is lowered to a predetermined position first, and the second tubing 12 is lowered and back-plugged with the sealing sleeve 122 and the first tubing 11;

[0049] After that, the annular chamber 13 formed between the first tubing 11 and the second tubing 12 is pressurized, so as to make the packer 17 set in the casing 10, thereby limiting the axial position of the device in the casing 10.

[0050] Preferably, at this time, the bridge joint 121 is radially aligned with the production channel 101, thereby ensuring that the oil and gas returned from the production channel 101 can smoothly pass through the bridge joint 121 into the second tubing 12.

[0051] After that, after the sealing is qualified, continue to pressurize to knock down the pressure holding ball seat 15.

[0052] Finally, fluid is injected into the annular chamber 13 formed between the first tubing 11 and the second tubing 12, and the downhole oil and gas is lifted to the ground through the oil pump 14 in sequence through the production channel 101 and the bridge joint 121, thereby completing the separate layer injection and production work.

[0053] It is worth noting that the above-mentioned fluid includes any one of gas and liquid.

[0054] Example one

[0055] If the downwardly injected fluid is gas, the calculation process of the throttling pressure difference of the gas is as follows:

[0056] According to the isentropic principle of the gas nozzle, for the subcritical flow state, the relationship between the gas flow and the pressure ratio is as follows:

[0057]

[0058] The equivalent diameter of the annular cross-sectional area of the annular chamber 13 is set to 45.7 mm, so the throttling pressure difference generated by the nitrogen injection of the annular chamber 13 with a length of 5000 m is calculated by the gas flow formula when P1=40 MPa.

[0059] In this embodiment, the annular chamber 13 meets the gas injection requirements: ΔP single string = P1-P2 = 0.0003 MPa; ΔP = ΔP single string * 500 = 0.15 MPa.

[0060] qsc—volumetric flow rate through the choke (at standard conditions), 104m3 / d; P1, P2—pressure before and after the choke, MPa; d—choke orifice diameter, mm; T1—temperature before the choke, K; Z1—deviation factor at T1 and P1; γg—relative density of gas; K—adiabatic exponent; P2 / P1—pressure ratio.

[0061] Example two

[0062] If the downward injection fluid is liquid, the liquid throttling pressure difference calculation process is as follows:

[0063] According to Bernoulli equation and fluid continuity equation:

[0064]

[0065] The annular cross-sectional area equivalent diameter of the annular chamber 13 is set to 45.7 mm, and the formula is brought into calculation, and the throttling pressure difference generated by the water injection in the annular chamber 13 with a length of 5000 m.

[0066] In this embodiment, the annular chamber 13 meets the gas injection requirement: ΔP=0.43 MPa

[0067] P - pressure; ρ - density; V - velocity; h - plumb height; g - gravitational acceleration; C - constant

[0068] ΔP - nozzle throttling pressure difference, Pa; ρ - injection liquid density, kg / m3; Q - displacement, m3 / s; C_d^2 - nozzle flow coefficient, dimensionless; d - nozzle diameter, m.

[0069] Compared with the prior art, the advantages of the utility model lie in:

[0070] Firstly, the utility model is a complete well completion process matching technology, which can realize liquid and gas injection in the lower part and oil and gas production in the upper part, thereby forming a set of unique separate layer injection and production process technology. In addition, the utility model can effectively improve the injection and production well pattern, thereby fully excavating the remaining oil and gas in the well by downward injection of fluid.

[0071] Secondly, the device has the advantages that the downward injection fluid pressure is not limited and the packer 17 is easy to unblock, thereby effectively assisting the efficient development of oil and gas reservoirs, which has extremely important significance for promoting the progress of oil production process technology, and can be popularized and applied in other domestic oilfields.

[0072] The above is only the preferred embodiment of the utility model, but the protection scope of the utility model is not limited thereto. Those skilled in the art can easily make changes or variations within the disclosed scope of the utility model, and such changes or variations should be covered in the protection scope of the utility model. Therefore, the protection scope of the utility model should be subject to the protection scope of the claims.

Claims

1. A device for separate layer injection and production in the same well, characterized in that, Comprise: a casing (10), and a layered injection-production mechanism arranged in the casing (10), the layered injection-production mechanism comprising a first tubing (11) and a second tubing (12) concentrically arranged in the first tubing (11); wherein a production channel (101) allowing oil and gas to flow is formed on the casing (10), and a bridge joint (121) arranged corresponding to the production channel (101) is arranged on the side wall of the second tubing (12).

2. The separate layer injection and production device in the same well according to claim 1, characterized in that, An annular chamber (13) for injecting fluid downhole is formed between the first tubing (11) and the second tubing (12).

3. The separate layer injection and production device in the same well according to claim 2, characterized in that, A pump (14) is arranged in the second tubing (12), which can lift the oil and gas up to the ground after the fluid is injected downhole through the annular chamber (13).

4. The separate layer injection and production device of the same well according to claim 3, characterized in that, A sealing sleeve (122) is arranged at the top of the bridge joint (121), and the bottom of the second tubing (12) is nested in the sealing sleeve (122).

5. The separate layer injection and production device of the same well according to claim 4, characterized in that, The layered injection-production device in the same well further comprises an injection pipe arranged below the first tubing (11), and a pressure containment ball seat (15) for plugging the injection pipe.

6. The separate layer injection and production device of the same well according to claim 5, characterized in that, The injection pipe comprises a first pipe body (161) configured in the form of a hollow cone, and a second pipe body (162) arranged below the first pipe body (161) and configured in the form of a hollow sleeve, wherein the pressure containment ball seat (15) is within the range of the second pipe body (162).

7. The separate layer injection and production device of the same well according to claim 6, characterized in that, A packer (17) for setting the casing (10) is sleeved outside the second pipe body (162).

8. The separate layer injection and production device of the same well according to claim 7, characterized in that, An injection valve (18) for communicating with the annular chamber (13) is arranged above the casing (10), and a production valve (19) for communicating with the second tubing (12) is arranged above the casing (10).

9. The separate layer injection and production device of the same well according to claim 8, characterized in that, The fluid comprises any one of gas and liquid.

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