Intelligent stratified injection and production tubing and process for carbon dioxide throughput

Abstract

This invention relates to a smart stratified injection-production string for carbon dioxide injection, comprising a first tubing and a second tubing connected by a backwash valve or a release tool. A hydraulic feedback pump is installed on the first tubing, and several packers are installed at intervals on the second tubing. A smart control switch tool is installed between two adjacent packers, each corresponding to an oil layer. An anchoring tool is also installed on the second tubing. This invention enables stratified injection, well shut-in, well release, and stratified production of carbon dioxide in any one or more layers without moving the injection-production string. This effectively improves the effective utilization rate of carbon dioxide, the degree of oil layer utilization, and the injection-production conversion efficiency, thereby increasing injection-production efficiency and oil recovery rate, reducing well workover work, well occupation time, and well cleaning and well layer contamination, and lowering operating costs.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of oil and gas exploitation, and particularly relates to a carbon dioxide huff and puff intelligent zonal injection and production string and a process method. BACKGROUND

[0002] Carbon dioxide has good viscosity reduction and oil displacement effects, and good oil increasing effects have been achieved in low-permeability reservoirs and high-viscosity oil reservoirs, which can effectively improve the oil recovery ratio. However, there is no reliable zonal injection and production control tool to control carbon dioxide zonal injection, zonal soak, efficient injection and production conversion and zonal oil production at present, so that the carbon dioxide huff and puff production mode is general injection and general lifting, the oil layers with large interlayer property differences interfere with each other seriously during carbon dioxide huff and puff, so that part of the relatively low-permeability oil layers cannot be effectively developed, and in the multi-cycle carbon dioxide huff and puff operation, repeated well repair operations are needed for injection and production conversion, the well shut-in time is long, the well killing operation is easy to pollute the oil layer, the operation cost is high, the production efficiency is low, and the production demand cannot be met. SUMMARY

[0003] The application provides a carbon dioxide huff and puff intelligent zonal injection and production string and a process method, solves the technical problems of carbon dioxide injection into a single layer in a general huff and puff well, low effective utilization rate, low injection and production conversion efficiency, and uneven oil layer development degree, can realize multi-cycle carbon dioxide zonal huff and puff and efficient injection and production conversion without moving the injection and production string, improves the carbon dioxide huff and puff production efficiency and the oil recovery ratio, reduces the well repair operation amount and the well occupation time, avoids oil layer pollution, and reduces the operation cost.

[0004] The application solves the technical problems by adopting the following technical scheme:

[0005] The carbon dioxide huff and puff intelligent zonal injection and production string comprises a first oil pipe and a second oil pipe, the first oil pipe and the second oil pipe are connected through a reverse well killing valve or a releasing tool, a hydraulic feedback pump is installed on the first oil pipe, a plurality of packers are installed on the second oil pipe at intervals, an intelligent control switch tool is installed between two adjacent packers, the intelligent control switch tools correspond to oil layers respectively, and an anchoring tool is further installed on the second oil pipe.

[0006] Further, the intelligent control switch tool comprises an outer shell and a control switch module installed in the outer shell.

[0007] The control switch module comprises a protection shell and an overflow valve, one end of the protection shell is fixedly connected with the outer shell, the other end is fixedly connected with the overflow valve, the other end of the overflow valve is through connection with the overflow hole on the side wall of the outer shell, and the inside of the outer shell can form a through liquid channel in the axial direction; a micro-processing module and a driving mechanism are installed in the protection shell, the driving mechanism is fixedly connected with an injection and sampling valve seat through a transmission shaft, a movable injection and sampling valve is fixedly installed on the injection and sampling valve seat, a fixed injection and sampling valve is also fixedly installed in the protection shell, the contact surface of the fixed injection and sampling valve and the movable injection and sampling valve is sealingly matched, a radial through bridge channel is arranged through the protection shell and the injection and sampling valve seat, an axial through movable hole is arranged in the movable injection and sampling valve, an axial through fixed hole is arranged in the fixed injection and sampling valve, the bridge channel is in through connection with the movable hole, and the fixed hole is in through connection with the overflow valve; when the driving mechanism drives the movable injection and sampling valve to rotate, the movable hole and the fixed hole are periodically communicated or staggered.

[0008] A positioning and angle sensor is also installed on the injection and sampling valve seat, the positioning and angle sensor is circuit-connected with the micro-processing module, and the micro-processing module is circuit-connected with the driving module and can control the working of the driving module.

[0009] Further, a pressure sensor is also included, the pressure sensor can detect the pressure in the liquid channel, and the pressure sensor is circuit-connected with the microprocessor and transmits the detected pressure signal to the microprocessor.

[0010] Further, an overflow valve core is arranged in the overflow valve, a through injection throat is arranged on the overflow valve core; the fluid entering through the bridge channel can enter the overflow hole through the injection throat, or the fluid entering from the overflow hole can push away the overflow valve core and enter the liquid channel through the bridge channel.

[0011] Further, a power supply is also installed in the protection shell, the power supply is circuit-connected with the pressure sensor, the microprocessor, the driving mechanism and the positioning and angle sensor and supplies power for them.

[0012] Further, the protection shell comprises a protection cover, an upper protection shell and a lower protection shell, one end of the protection cover is fixedly connected with the outer shell, the other end is fixedly connected with one end of the upper protection shell, a pressure sensor compartment is fixedly installed between the other end of the upper protection shell and the lower protection shell, the other end of the lower protection shell is fixedly connected with the overflow valve, and the pressure sensor is installed in the pressure sensor compartment.

[0013] Further, the outer shell comprises an upper joint, an outer cylinder and a lower joint, the upper joint, the outer cylinder and the lower joint are fixedly connected in sequence, one end of the protection cover is fixedly connected with the inner wall of the upper joint, and the overflow hole is arranged on the side wall of the lower joint.

[0014] Further, the driving mechanism comprises a driving motor, an output end of the driving motor is connected with a speed reducer, and an output end of the speed reducer is fixedly connected with the transmission shaft.

[0015] Further, the fixed injection-production valve is fixed on the sidewall of the lower protective housing by means of a pin.

[0016] The carbon dioxide huff and puff intelligent layered injection-production process method comprises the following steps:

[0017] The carbon dioxide huff and puff intelligent layered injection-production string is lowered into a well, the packer and the anchoring tool are set, and the carbon dioxide huff and puff intelligent layered injection-production string is anchored on the casing.

[0018] Carbon dioxide layered injection / huff and puff: the corresponding intelligent control switch tool of the carbon dioxide injection layer is controlled to be opened, while the corresponding intelligent control switch tool of other layers is controlled to be closed, carbon dioxide is injected through a tubing, the corresponding layer is injected, the huff and puff of the layer is realized by controlling the corresponding intelligent control switch tool of the carbon dioxide injection layer to be closed, and the like is sequentially realized, so that the carbon dioxide layered rotation injection and huff and puff of any layer or multiple layers are realized.

[0019] Carbon dioxide huff and puff injection / recovery conversion: when production is needed after the carbon dioxide layered injection and huff and puff are completed, the intelligent control switch tool of the carbon dioxide injection target layer is controlled to be opened to form an injection-production channel, while the intelligent control switch tool of other layers is controlled to be closed to form an injection-production channel, the sucker rod is lowered on the ground and connected with the hydraulic feedback pump, and the hydraulic feedback pump is controlled to be moved up and down to produce oil.

[0020] The steps of the carbon dioxide layered injection / huff and puff and the carbon dioxide huff and puff injection / recovery conversion can realize the carbon dioxide injection and oil production process of any layer or multiple layers.

[0021] The advantages and positive effects of the present application are as follows:

[0022] The present application can control the carbon dioxide layered injection, layered huff and puff, layered blowout and layered production of any layer or multiple layers without moving the injection-production string, effectively improves the carbon dioxide utilization rate, the oil layer producing degree and the injection-production conversion efficiency, improves the injection-production efficiency and the crude oil recovery rate, reduces the workover operation amount, the occupied well time, the pollution of the oil layer during the well cleaning and pressure testing, and the operation cost. BRIEF DESCRIPTION OF DRAWINGS

[0023] The technical solutions of the present application will be further described in detail below by combining the drawings and examples, but it should be known that the drawings are designed for the purpose of explanation, and thus are not regarded as the limitation of the scope of the present application. In addition, unless specifically indicated, the drawings are only intended to conceptually illustrate the structural configuration described herein, and are not necessarily drawn according to the scale.

[0024] Figure 1 is a structural schematic diagram of the carbon dioxide huff and puff intelligent layered injection and production pipe column in a carbon dioxide injection state provided by the embodiment of the present application;

[0025] Figure 2 is a structural schematic diagram of the carbon dioxide huff and puff intelligent layered injection and production pipe column in an oil production state provided by the embodiment of the present application;

[0026] Figure 3 is a structural schematic diagram of the carbon dioxide huff and puff intelligent layered injection and production pipe column in a releasing state provided by the embodiment of the present application;

[0027] Figure 4 is a structural schematic diagram of the intelligent control switch tool of the carbon dioxide huff and puff intelligent layered injection and production pipe column provided by the embodiment of the present application; DETAILED DESCRIPTION

[0028] First of all, it should be noted that the specific structure, features and advantages of the present application will be specifically described below in an exemplary manner, however, all the descriptions are only for illustration and should not be understood as any limitation on the present application. In addition, any single technical feature described or implied in the embodiments mentioned in the present application, or any single technical feature shown or implied in the drawings, can still continue to be combined or deleted between these technical features (or their equivalents), so as to obtain more other embodiments of the present application which can not be directly mentioned in the present application. In addition, in order to simplify the drawing, the same or similar technical features can only be marked in one place in the same drawing.

[0029] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the present application is usually placed, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0030] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0031] As Figures 1 to 4 , the carbon dioxide huff and puff intelligent layered injection and production pipe column provided by the embodiment includes a first oil pipe 2, a second oil pipe 22, and the like Figure 1As shown, the first tubing and the second tubing are connected through the reverse flushing well valve 9, or the first tubing and the second tubing are connected through the releasing tool 901, the first tubing is provided with the hydraulic feedback pump, the second tubing is provided with a plurality of packers at intervals, the adjacent two packers are provided with the intelligent control switch tool, the intelligent control switch tool corresponds to the oil layer respectively, and the second tubing is further provided with the anchoring tool.

[0032] Specifically, the hydraulic feedback pump comprises an upper hydraulic feedback pump plunger 4, a lower hydraulic feedback pump plunger 5, an upper hydraulic feedback pump cylinder 6, and a lower hydraulic feedback pump cylinder 8. The sucker rod 3 is threadedly connected with the upper hydraulic feedback pump plunger 4. The upper hydraulic feedback pump plunger 4 and the lower hydraulic feedback pump plunger 5 are integrated, and the outer diameter of the upper hydraulic feedback pump plunger 4 is greater than that of the lower hydraulic feedback pump plunger 5. The upper hydraulic feedback pump cylinder 6 and the lower hydraulic feedback pump cylinder 8 are integrated, and the inner diameter of the upper hydraulic feedback pump cylinder 6 is greater than that of the lower hydraulic feedback pump cylinder 8. The upper hydraulic feedback pump plunger 4 and the lower hydraulic feedback pump plunger 5 can be gap-fitted with the upper hydraulic feedback pump cylinder 6 and the lower hydraulic feedback pump cylinder 8 respectively. When the upper hydraulic feedback pump plunger 4 and the lower hydraulic feedback pump plunger 5 are separated from the upper hydraulic feedback pump cylinder 6 and the lower hydraulic feedback pump cylinder 8 respectively, an injection channel 7 can be formed. The reverse flushing well valve 9 is an outward one-way valve, which allows the fluid in the casing 1 to enter the tubing through the reverse flushing well valve 9, but prevents the fluid in the tubing from entering the casing 1 through the reverse flushing well valve 9. In this embodiment, as shown, Figure 1 As shown, the packers include a first packer 11, a second packer 13, and a third packer 15. The end of the second tubing is provided with a plug 17. The first intelligent control switch tool 12 is installed between the first packer 11 and the second packer 13. The second intelligent control switch tool 14 is installed between the second packer 13 and the third packer 15. The third intelligent control switch tool 16 is installed between the third packer 15 and the plug 17. The first intelligent control switch tool 12, the second intelligent control switch tool 14, and the third intelligent control switch tool 16 correspond to the first oil layer 19, the second oil layer 20, and the third oil layer 21 respectively. The anchoring tool is installed on the second tubing above the first packer 11. It should be noted that the process string is not limited to the separate layer injection and production of three oil layer sections. The number of packers and intelligent control switch tools can be adjusted according to the number of oil layer sections to realize the integrated production of carbon dioxide huff and puff in multiple oil layer sections.

[0033] After the carbon dioxide intelligent separate layer injection and production pipe column is lowered into the well, the ground pump truck pressurizes from the first oil pipe 2, simultaneously setting the anchoring tool 10, the first packer 11, the second packer 13 and the third packer 15, and anchoring the carbon dioxide intelligent separate layer injection and production pipe column on the casing 1, and after the sucker rod 3 is threadedly fixedly connected with the upper plunger 4 and the lower plunger 5 of the hydraulic feedback pump, the upper pump cylinder 6 and the lower pump cylinder 8 of the hydraulic feedback pump are respectively lowered into the hydraulic feedback pump from the oil pipe, and the ground installs the pumping unit, and the pumping unit is connected with the sucker rod.

[0034] The intelligent control switch tool comprises an outer shell and a control switch module installed in the outer shell.

[0035] The control switch module comprises a protective shell and an overflow valve, one end of the protective shell is fixedly connected with the outer shell, the other end is fixedly connected with the overflow valve, the other end of the overflow valve is in through connection with an overflow hole on the side wall of the outer shell, and an axial through liquid passage can be formed in the inner part of the outer shell; a micro-processing module and a driving mechanism are installed in the protective shell, the driving mechanism is fixedly connected with an injection-production valve seat through a transmission shaft, a movable injection-production valve is fixedly installed on the injection-production valve seat, a fixed injection-production valve is also fixedly installed in the protective shell, and the contact surface of the movable injection-production valve and the fixed injection-production valve is in sealing cooperation; a radial through bridge passage is arranged through the protective shell and the injection-production valve seat, an axial through movable hole is arranged in the movable injection-production valve, an axial through fixed hole is arranged in the fixed injection-production valve, the bridge passage is in through connection with the movable hole, and the fixed hole is in through connection with the overflow valve; when the driving mechanism drives the movable injection-production valve to rotate, the movable hole and the fixed hole are periodically connected or staggered.

[0036] A positioning and angle sensor is also installed on the injection-production valve seat, the positioning and angle sensor is in circuit connection with the micro-processing module, the micro-processing module is in circuit connection with the driving module and can control the working of the driving module; it should be noted that the microprocessor can adopt an existing product, as long as the signal receiving and control functions are realized, and it is not necessary to be limited to a specific product model.

[0037] A pressure sensor is also included, the pressure sensor can detect the pressure in the liquid passage, and the pressure sensor is in circuit connection with the microprocessor and transmits the detected pressure signal to the microprocessor.

[0038] The over-flow valve is internally provided with an over-flow valve core, and the over-flow valve core is provided with a through injection throat; the fluid entering through the bridge channel can enter the over-flow hole through the injection throat, or the fluid entering from the over-flow hole can push away the over-flow valve core and enter the liquid channel through the bridge channel; it should be noted that in the embodiment, the over-flow valve core 124 is a long cone structure, and the height of the cone is greater than the maximum aperture of the over-flow valve 123, which avoids the over-flow valve core 124 from turning over in the hole of the over-flow valve 123, guarantees the one-way sealing of the over-flow valve core 124 and the hole of the over-flow valve 123 in the high-deviation well and the horizontal well, and makes the layered injection and production intelligent control switch tool applicable to the straight well, the high-deviation well and the horizontal well; in addition, the injection throat 125 can be arranged at the center of the over-flow valve core 124 or on the circumferential wall of the over-flow valve core 124, and is not limited to one injection throat.

[0039] Specifically, as Figure 1As shown, the protective shell includes a protective cover 104, an upper protective shell 105, a lower protective shell 112, one end of the protective cover is fixedly connected with the outer shell, the other end is fixedly connected with one end of the upper protective shell, the other end of the upper protective shell is fixedly installed with a pressure sensor compartment 108 between the lower protective shell, the other end of the lower protective shell is fixedly connected with the overflow valve 123, the pressure sensor 109 is installed in the pressure sensor compartment, the battery 106 is installed in the upper protective shell 105, and the battery is connected with the pressure sensor, the microprocessor, the driving mechanism, the positioning and angle sensor circuit and is powered by the power supply line 107 and the power supply and signal line 113; It should be noted that the protective cover 104, the upper protective shell 105 and the lower protective shell 112 can be made of stainless steel, which can ensure strength and certain corrosion resistance; The upper end of the pressure sensor compartment 108 is threadedly and sealingly connected with the lower end of the upper protective shell 105, and the lower end is threadedly and sealingly connected with the upper end of the lower protective shell 112; The pressure sensor 109 and the pressure signal line 110 are fixedly installed on the pressure sensor compartment 108; The pressure sensor 109 transmits the pressure value in the liquid channel 102 to the microprocessor 111 through the pressure signal line 110; The lower end of the lower protective shell 112 is sealingly connected with the upper end of the overflow valve 123; The lower protective shell 112 has the microprocessor 111, the power supply and signal line 113, the driving mechanism, the transmission shaft 115, the positioning and angle sensor 116, the injection and sampling valve seat 117, the movable injection and sampling valve 120 and the fixed injection and sampling valve 121; The microprocessor 111 can accurately control the rotation angle of the driving motor and the speed reducer through the feedback signal of the positioning and angle sensor 116; The driving mechanism includes a driving motor, the output end of the driving motor is connected with a speed reducer, the output end of the speed reducer is fixedly connected with the transmission shaft, the driving motor 114, the speed reducer, the transmission shaft 115, the injection and sampling valve seat 117 and the movable injection and sampling valve 120 are sequentially fixedly connected, the transmission shaft 115 transmits the power output by the driving motor and the speed reducer to control the rotation of the injection and sampling valve seat 117 and the movable injection and sampling valve 120; The positioning and angle sensor 116 is on the injection and sampling valve seat 117, accurately records the rotation angle and position of the injection and sampling valve seat 117, and transmits the recorded data to the microprocessor 111 through the power supply and signal line 113; The movable injection and sampling valve 120 is fixed on the injection and sampling valve seat 117, and the upper bridge type channel 118 is in communication with the movable hole 119 on the movable injection and sampling valve 120; The fixed injection and sampling valve 121 is fixed on the lower protective shell 112 by a pin, and is sealingly matched with the end surface of the movable injection and sampling valve 120, the fixed hole 122 rotates with the movable injection and sampling valve 120 to periodically communicate or disconnect with the movable hole 119; The fixed hole 122 is in communication with the inner hole of the overflow valve 123;The overflow valve core 124 is on the overflow valve 123 channel, and an injection throat 125 with a smaller diameter than the inner hole of the overflow valve 123 is arranged on the overflow valve core 124; the injection throat 125 has a smaller diameter to ensure smooth injection of carbon dioxide from the injection throat 125 and has sufficient throttling effect; the lower connector 126 is threadedly and sealingly connected with the outer cylinder 103, and an overflow hole 127 is arranged on the lower connector 126 and communicates with the injection throat 125;

[0040] The outer shell body comprises an upper connector, an outer cylinder, and a lower connector, which are sequentially fixedly connected; one end of the protective cover body is fixedly connected with the inner wall of the upper connector, and the overflow hole is arranged on the side wall of the lower connector; the upper connector 101 is threadedly and sealingly connected with the outer cylinder 103; the outer cylinder 103 is threadedly and sealingly connected with the lower connector 125; the upper end of the protective cover body 104 is threadedly fixed with the lower end of the upper connector 101, and the lower end of the protective cover body 104 is threadedly and sealingly connected with the upper end of the upper protective steel sleeve 105.

[0041] The layered injection and production intelligent control switch tool is lowered into the well along with the pipe column after several groups of timing opening and closing times are set in the microprocessor in advance according to the operation requirement, and in addition, the opening or closing of the layered injection and production intelligent control switch tool can also be controlled by different pressure signals.

[0042] As an example, when carbon dioxide injection construction is performed: the microprocessor 111 of the layered injection and production intelligent control switch tool intelligently controls the driving motor and the reducer to rotate by a certain angle according to the timing opening time set in advance or the corresponding pressure signal received by the pressure sensor 109 from the liquid channel 102 according to the corresponding pressure signal applied by the ground, drives the transmission shaft 115, the injection and production valve seat 117, and the movable injection and production valve 120 to rotate together, makes the movable hole 119 communicate with the fixed hole 122, and thus makes the liquid channel 102, the bridge channel 118, the inner hole of the overflow valve 123, the injection throat 125, and the overflow hole 127 communicate, that is, the injection and production channel is opened, carbon dioxide is injected into the oil layer from the liquid channel 102, the bridge channel 118, the injection throat 125 on the overflow valve core 124, and the overflow hole 127, and the injection throat 125 has a smaller diameter to ensure smooth injection of carbon dioxide from the injection throat 125 and has sufficient throttling effect, so that the ground pump truck can quickly rise and send a pressure signal;

[0043] When the carbon dioxide injection is followed by oil production operation: after the carbon dioxide is injected into the layer and the well is left to soak, the microprocessor 111 opens according to the preset timing or identifies the corresponding pressure signal applied by the pressure sensor 109 from the liquid passage 102, and intelligently controls the driving motor and the reducer to rotate a certain angle, which drives the transmission shaft 115, the injection-production valve seat 117 and the movable injection-production valve 120 to rotate, so that the movable hole 119 and the fixed hole 122 are communicated, thereby making the central passage 102, the bridge passage 118, the inner hole of the overflow valve 123, the injection throat 125 and the overflow hole 127 communicated, i.e. the injection-production passage is opened, the oil liquid enters the overflow hole 127, pushes away the overflow valve core 124, and then flows through the larger aperture between the overflow valve core 124 and the overflow valve 123, and then flows into the oil pipe column through the bridge passage 118 and the liquid passage 102, and is lifted to the ground, thereby avoiding the blockage of the injection throat 125 by thick oil.

[0044] It should be noted that when the ground injection pump truck sends a pressure signal to control the opening or closing of the corresponding intelligent control switch tool, the change of the opening or closing state of the intelligent control switch tool can be determined by the pressure relief speed of the injection pump truck; if the pressure rise speed of the injection pump truck becomes faster and the pressure relief speed becomes slower, it indicates that the corresponding intelligent control switch tool has been closed; if the pressure rise speed of the injection pump truck becomes slower and the pressure relief speed becomes faster, it indicates that the corresponding intelligent control switch tool has been opened.

[0045] When the carbon dioxide huff and puff intelligent layered injection-production string is used for operation, the following steps are included:

[0046] Carbon dioxide layered injection / soaking: the sucker rod 3 is lifted on the ground, the upper plunger 4 and the lower plunger 5 of the hydraulic feedback pump are lifted out of the upper pump cylinder 6 and the lower pump cylinder 8 of the hydraulic feedback pump respectively, and the injection passage 7 is in an open state, as shown in Figure 1; through precise timing or from tubing pressure signal, control the carbon dioxide injection into the target layer of the intelligent control switch tool to open the injection and production channel, while controlling the intelligent control switch tool of other layers to close the injection and production channel; so as to realize the carbon dioxide injection and layering; for example: carbon dioxide is injected into the first oil layer 19, and through precise timing or from the tubing pressure signal, the first intelligent control switch tool 12 is intelligently controlled to open the injection and production channel, while the second intelligent control switch tool 14 and the third intelligent control switch tool 16 corresponding to the second oil layer 20 and the third oil layer 21 are intelligently controlled to close the injection and production channel (hibernate); carbon dioxide is injected from the tubing, and through the injection channel 7, from the outside of the upper plunger 4 and the lower plunger 5 of the hydraulic feedback pump to the bottom of the upper pump cylinder 6 and the lower pump cylinder 8 of the hydraulic feedback pump, and then through the tubing 2, the reverse flushing well valve 9, the anchoring tool 10 and the center tube of the packer, into the first oil layer 19 from the injection and production channel of the first intelligent control switch tool 12; when the second oil layer 20 is needed, the first intelligent control switch tool 12 and the third intelligent control switch tool 16 are intelligently controlled to close the injection and production channel (hibernate), while the second intelligent control switch tool 14 corresponding to the second oil layer 20 is intelligently controlled to open the injection and production channel; carbon dioxide is injected from the tubing, and through the injection channel 7, from the outside of the upper plunger 4 and the lower plunger 5 of the hydraulic feedback pump to the bottom of the upper pump cylinder 6 and the lower pump cylinder 8 of the hydraulic feedback pump, and then through the tubing and the reverse flushing well valve 9, the anchoring tool 10 and the center tube of the packer, into the second oil layer 20 from the injection and production channel of the second intelligent control switch tool 14; other layers are sequentially used to realize the carbon dioxide injection and hibernation of any layer or multiple layers; it should be noted that corrosion inhibitors can be injected from the casing 1 into the tubing to reduce the corrosion of the string.

[0047] Carbon dioxide injection / production conversion: after the carbon dioxide injection and hibernation of the layers are completed, when production is needed, the ground lowers the pumping rod 3, so that the upper plunger 4 and the lower plunger 5 of the hydraulic feedback pump are respectively placed in the upper pump cylinder 6 and the lower pump cylinder 8 of the hydraulic feedback pump at the normal production position, so that the upper plunger 4 and the lower plunger 5 of the hydraulic feedback pump move up and down for normal oil pumping production, and the injection channel 7 is always in a closed state (such as Figure 2); when layered oil production, through the precise timing from the tubing pressure signal, intelligent control of carbon dioxide injection into the target layer of intelligent control switch tool to open injection and production channel, and intelligent control of the corresponding intelligent control switch tool of other oil layers to close injection and production channel, so as to realize layered lifting production; for example: when the first oil layer 19 is produced, through the precise timing or from the tubing pressure signal, the first intelligent control switch tool 12 is intelligently controlled to open the injection and production channel, and the second oil layer 20 and the third oil layer 21 corresponding to the intelligent control switch tool are intelligently controlled to close the injection and production channel. When the upper and lower plunger 4 and the lower plunger 5 of the hydraulic feedback pump move normally to produce oil, under the action of suction, the liquid flow in the first oil layer 19 enters the injection and production channel of the first intelligent control switch tool 12, flows into the tubing, and then flows to the lower pump cylinder 8 and the upper pump cylinder 6 of the hydraulic feedback pump through the center pipe of the packer, the anchoring tool 10 and the reverse flushing valve 9, and is lifted to the ground; when the second oil layer 20 needs to be changed to produce oil, through the precise timing or from the tubing pressure signal, the second intelligent control switch tool 14 is intelligently controlled to open the injection and production channel, and the first oil layer 19 and the third oil layer 21 corresponding to the intelligent control switch tool are intelligently controlled to close the injection and production channel; when the upper and lower plunger 4 and the lower plunger 5 of the hydraulic feedback pump move normally to produce oil, under the action of suction, the liquid flow in the second oil layer 20 enters the injection and production channel of the second intelligent control switch tool 14, flows into the tubing, and then flows to the lower pump cylinder 8 and the upper pump cylinder 6 of the hydraulic feedback pump through the center pipe of the packer, the anchoring tool 10 and the reverse flushing valve 9, and is lifted to the ground; other similar, realize any one or more layers of layered rotation production; it should be noted that when the gas content in the pipe string is high, which affects the pump efficiency, the well flushing fluid can be injected from the oil sleeve annulus 18, enters the tubing from the reverse flushing valve 9, and is circulated by the hydraulic feedback pump to displace the gas in the tubing, so as to realize the circulation of well flushing and degassing;

[0048] Carbon dioxide huff and puff conversion: after the production is completed, when carbon dioxide needs to be injected into the target layer and stewed, the sucker rod 3 is lifted on the ground, the upper plunger 4 and the lower plunger 5 of the hydraulic feedback pump are lifted out of the upper pump cylinder 6 and the lower pump cylinder 8 respectively, and the injection channel 7 is in an open state (such as Figure 1 ); through the precise timing or from the tubing pressure signal, the intelligent control switch tool of carbon dioxide injection into the target layer is intelligently controlled to open the injection and production channel, and the corresponding intelligent control switch tool of other oil layers is intelligently controlled to close the injection and production channel, so as to realize the layered injection and layered stewing of carbon dioxide again.

[0049] The backwashing valve 9 in the carbon dioxide huff and puff intelligent layered injection and production integrated process and pipe string can be replaced by a releasing tool 901, the pump cylinder 6, the injection channel 7, the lower pump cylinder 8 of the hydraulic feedback pump, the releasing tool 901, the anchoring tool 10, the first packer 11, the first intelligent control switch tool 12, the second packer 13, the second intelligent control switch tool 14, the third packer 15, the third intelligent control switch tool 16, and the plug 17 are sequentially fixed and sealed in series from top to bottom by the oil pipe, and are sequentially lowered into the designed position in the casing 1; the ground pump truck pressurizes from the oil pipe, simultaneously sets the anchoring tool 10, the first packer 11, the second packer 13, and the third packer 15, and anchors the carbon dioxide huff and puff intelligent layered injection and production integrated pipe string on the casing 1, continues to pressurize after the first oil layer 19, the second oil layer 20, and the third oil layer 21 are sealed, and releases the releasing tool 901 to separate the first oil pipe from the second oil pipe, the anchoring tool 10, the first packer 11, the first intelligent control switch tool 12, the second packer 13, the second intelligent control switch tool 14, the third packer 15, the third intelligent control switch tool 16, and the plug 17 on the lower second oil pipe are fixed on the casing 1 and left in the well bottom, and the pump cylinder 6 and the lower pump cylinder 8 on the upper first oil pipe can be pulled out for maintenance or replacement, facilitating pump inspection operation (such as Figure 3 ); and the carbon dioxide layered injection, layered soak, injection / production conversion, and layered production mode remain unchanged.

[0050] The above embodiments have been described in detail, but the content described is only the preferred embodiments of the present application, and cannot be considered as limiting the implementation scope of the present application. Any equivalent changes and improvements made according to the scope of the present application should still belong to the patent coverage scope of the present application.

Claims

1. A process method of intelligent zonal injection and production of carbon dioxide huff and puff, the process method is carried out by using the intelligent zonal injection and production string of carbon dioxide huff and puff, characterized in that, The carbon dioxide huff and puff intelligent layered injection and production pipe column comprises a first oil pipe and a second oil pipe, the first oil pipe and the second oil pipe are connected through a backwashing well valve or a releasing tool, a hydraulic feedback pump is installed on the first oil pipe, a plurality of packers are installed on the second oil pipe at intervals, an intelligent control switch tool is installed between two adjacent packers, the intelligent control switch tool corresponds to an oil layer respectively, and an anchoring tool is further installed on the second oil pipe; The intelligent control switch tool comprises an outer shell and a control switch module installed in the outer shell; The control switch module comprises a protective shell and an overflow valve, one end of the protective shell is fixedly connected with the outer shell, the other end is fixedly connected with the overflow valve, the other end of the overflow valve is through-connection with an overflow hole on the side wall of the outer shell, and an axial through liquid channel can be formed in the inner part of the outer shell; a microprocessor and a driving mechanism are installed in the protective shell, the driving mechanism is fixedly connected with an injection and production valve seat through a transmission shaft, a movable injection and production valve is fixedly installed on the injection and production valve seat, a fixed injection and production valve is further fixedly installed in the protective shell, the contact surface of the movable injection and production valve and the fixed injection and production valve is in sealing cooperation, a radial through bridge channel is arranged through the protective shell and the injection and production valve seat, an axial through movable hole is arranged in the movable injection and production valve, an axial through fixed hole is arranged in the fixed injection and production valve, the bridge channel is in through-connection with the movable hole, and the fixed hole is in through-connection with the overflow valve; when the driving mechanism drives the movable injection and production valve to rotate, the movable hole and the fixed hole are periodically communicated or staggered; A positioning and angle sensor is further installed on the injection and production valve seat, the positioning and angle sensor is in circuit connection with the microprocessor, and the microprocessor is in circuit connection with the driving module and can control the working of the driving module; A pressure sensor is further arranged, the pressure sensor can detect the pressure in the liquid channel, and the pressure sensor is in circuit connection with the microprocessor and transmits the detected pressure signal to the microprocessor; An overflow valve core is arranged in the overflow valve, and a through injection throat is arranged on the overflow valve core; the fluid entering through the bridge channel can enter the overflow hole through the injection throat, the fluid entering through the overflow hole can push away the overflow valve core, and then enter the liquid channel through the bridge channel; The method comprises the following steps: The carbon dioxide huff and puff intelligent layered injection and production pipe column is lowered into a well, the packers and the anchoring tool are set, and the carbon dioxide huff and puff intelligent layered injection and production pipe column is anchored on a casing; Carbon dioxide layered injection and huff and puff: the intelligent control switch tools corresponding to the oil layers are controlled to be opened, while the intelligent control switch tools corresponding to other oil layers are controlled to be closed, carbon dioxide is injected through the oil pipe, and the corresponding oil layers are injected, the huff and puff of the oil layers is realized by controlling the intelligent control switch tools corresponding to the injected carbon dioxide oil layers to be closed; other oil layers are sequentially injected and huffed and puffed in the same way, and the layered rotation injection and huff and puff of any one or more layers of carbon dioxide are realized. Carbon dioxide injection / production conversion: after the completion of carbon dioxide injection and soaking, when production is needed, the intelligent control switch tool controlling the carbon dioxide injection target layer opens the injection-production channel, while the intelligent control switch tool corresponding to other oil layers closes the injection-production channel. The ground lowers the sucker rod and connects it with the hydraulic feedback pump, and through the control operation of the hydraulic feedback pump, the oil production is carried out by moving up and down; The steps of repeated carbon dioxide injection / soaking and carbon dioxide injection / production conversion can realize carbon dioxide injection and oil production process in any one or more layers of oil reservoirs; When carbon dioxide injection is carried out: carbon dioxide is injected into the oil layer from the injection throat and overflow hole on the liquid channel, bridge channel and overflow valve core, and the injection throat has small aperture, which can not only ensure the smooth injection of carbon dioxide from the injection throat, but also has throttling effect, so that the ground pump truck can quickly rise pressure and send pressure signal; When carbon dioxide injection is carried out: carbon dioxide is injected into the oil layer from the injection throat and overflow hole on the liquid channel, bridge channel and overflow valve core, and the injection throat has small aperture, which can not only ensure the smooth injection of carbon dioxide from the injection throat, but also has throttling effect, so that the ground pump truck can quickly rise pressure and send pressure signal; 2. The intelligent zonal injection and production process method of carbon dioxide huff and puff according to claim 1, characterized in that: The protective shell further comprises a power supply, which is connected with the pressure sensor, microprocessor, driving mechanism, positioning and angle sensor circuit and supplies power for them.

3. The intelligent zonal injection and production process method of carbon dioxide huff and puff according to claim 1, characterized in that: The protective shell comprises a protective cover, an upper protective shell and a lower protective shell. One end of the protective cover is fixedly connected with the outer shell, and the other end is fixedly connected with one end of the upper protective shell. The pressure sensor compartment is fixedly installed between the other end of the upper protective shell and the lower protective shell. The other end of the lower protective shell is fixedly connected with the overflow valve. The pressure sensor is installed in the pressure sensor compartment.

4. The intelligent zonal injection and production process method of carbon dioxide huff and puff according to claim 3, characterized in that: The outer shell comprises an upper joint, an outer cylinder and a lower joint, which are fixedly connected in sequence. One end of the protective cover is fixedly connected with the inner wall of the upper joint. The overflow hole is located on the side wall of the lower joint.

5. The intelligent zonal injection and production process method of carbon dioxide huff and puff according to claim 1, wherein: The driving mechanism comprises a driving motor. The output end of the driving motor is connected with a speed reducer. The output end of the speed reducer is fixedly connected with the transmission shaft.

6. The intelligent zonal injection and production process method of carbon dioxide huff and puff according to claim 1, wherein: The fixed injection-production valve is fixed on the side wall of the lower protective shell by means of a pin.

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