WO2021004163A1

WO2021004163A1 - Packing method for injection and production in same well and well completion structure

Info

Publication number: WO2021004163A1
Application number: PCT/CN2020/090967
Authority: WO
Inventors: 裴柏林; 聂建飞
Original assignee: 安东柏林石油科技（北京）有限公司
Priority date: 2019-07-11
Filing date: 2020-05-19
Publication date: 2021-01-14
Also published as: CN110242264B; CN110242264A

Abstract

A packing method for injection and production in the same well and a well completion structure, the packing method comprising the following steps: (1) lowering a double-flow-channel tubular column into a well; (2) filling an annular space (6) between the double-flow-channel tubular column and the well wall with packing particles until the packing particles fill the annular space and accumulate to form a continuous packing body (13); and (3) sealing the annular space. According to the packing method and the well completion structure, the continuous packing body formed by accumulating in a shaft may pile up tp fill the whole section, the sealing and isolation effects are good, and the high spatial self-adaptivity is achieved. During the process of lowering the tubular column, the well completion structure is not hindered by a packer that is preset on the tubular column, the construction process is easy, and the problem in which the packer is jammed in the shaft may be avoided. In addition, the tubular column may be retrieved.

Description

Packing method and completion structure for same well injection and production

Technical field

The invention belongs to the field of oil and natural gas exploitation, and relates to a same well injection and production oil and gas well, in particular to a packing method and a completion structure for the same well injection and production.

Background technique

In the process of oil and natural gas exploitation, in order to improve the production effect of the reservoir, the development method of water injection and gas injection is usually used to displace formation oil, accelerate the oil and gas production rate and increase the ultimate recovery rate. The commonly used method in practice is to set up special water injection wells around the production wells. Because this method requires special water injection wells, it will inevitably increase the production cost; on the other hand, the oil reservoirs with cracks are prone to water channeling and the water driving effect is poor. . Based on the above problems, people have proposed the same well injection and production method. For example, Chinese patent CN201810104442.9 discloses a method of using double-layer concentric tubing or parallel dual tubing as dual-channel tubing strings to produce tight oil through carbon dioxide huff and puff transfer; CN201510506961.4 discloses a horizontal well staged fracturing Same well injection-production oil production method; CN201480038110.5 discloses an improved hydrocarbon recovery method using multiple induced fractures; CN201610294730.6 discloses a horizontal well injection-production asynchronous (ie breathing) production in fractured reservoirs Method; CN201710078354.1 discloses a zipper type (that is, alternate odd and even) double-fracturing horizontal well water injection huff and puff oil production method; CN201510103268.2 discloses a low-permeability offshore oil reservoir development of thick oil layers with one well and multiple controls method.

In the above technical scheme, in order to achieve the same well injection and production, the injection fractured well section and the production fractured well section need to be isolated and sealed to prevent the displacement medium (water, gas, etc.) output from the injection channel from passing through the dual-channel string The annulus between the well wall and the well wall flows directly to the production fracture position in the annulus and enters the production flow channel. The prior art usually adopts the method of setting packers at suitable positions to isolate and seal different well sections. Commonly used packers include external expansion packers with piston pressure sealant cylinders, and liquid expansion packers. In actual use, since injection and production in the same well often need to isolate multiple fractures and multiple well sections, it is necessary to install a larger number of packers in the wellbore, which will cause the following problems: First, the isolation effect is relatively high. Poor, especially when the wall of the wellbore is irregular, it is often impossible to achieve effective isolation, and the isolation effect cannot be tested, and the unsealed problem of a packer cannot be found in time, and timely remedy cannot be performed; There are a large number of packers, and the probability of packers getting stuck is greatly increased; in addition, the string with the packer cannot be put forward after being run into the well, which will seriously affect the subsequent operations of the construction well; the third is for casing injection Well, if there is a channel outside the casing, the existing packer cannot seal the channel. The existence of the above technical problems seriously restricts the application of the same well injection-production technology in actual production.

Summary of the invention

The purpose of the present invention is to overcome the defects of the prior art and provide a packing for same well injection and production with simple structure, convenient use, strong self-adaptive ability of packing, good packing effect, low cost, and easy recovery of pipe string. Method and completion structure.

In order to achieve the above objectives, the present invention adopts the following technical solutions:

A packing method for the same well injection and production, including the following steps: (1) a double-channel pipe string is run into the well; the double-channel pipe string includes an injection channel and a production channel, the injection channel One or more injection ports are provided, and the production flow channel is provided with one or more production outlets; (2) Packing particles in the annulus between the dual-channel pipe string and the well wall until the particles are full The annulus and accumulation form a continuous packer; (3) the annulus is closed.

Further, the wellhead of the well is provided with a wellhead device or a Christmas tree; the method for packing and packing particles is: injecting a filling fluid carrying the packing particles into the annulus through the casing annulus of the wellhead device or the Christmas tree; The method for closing the annulus is: closing the wellhead device or the casing annulus valve of the Christmas tree.

Further, the heel end of the double-fluid pipe string is provided with a packer with a packing channel; the method for packing and packing particles is: injecting a packing carrying the packing particles into the annulus through the filling port of the packer with packing channel The method of closing the annulus is: closing the filling port of the packer with a filling channel.

Further, the heel end of the double-fluid pipe string is provided with a liquid swelling packer; the method for packing and packing particles is: injecting a filling fluid carrying the packing particles into the annulus from the wellhead; the closed annulus The method is: after the filling is completed, the expansion packer will continue to expand to close the annulus.

Further, the packing particles include one or more of sand, sand, quartz sand, gravel, ceramsite, hollow glass beads or fly ash.

Further: The packing particles are spherical or special-shaped structures made of polyethylene, polypropylene, polystyrene, polyvinyl chloride, nylon 66 or styrene-divinylbenzene cross-linked copolymer, and have a particle size of 50-300 meshes. The density is 0.8-1.4g/cm ³ .

Further, the method for filling the annulus with packing particles is: injecting a filling liquid carrying the packing particles into the annulus.

Further, the filling fluid is formation water, surface fresh water or seawater, and the volume ratio concentration of the packing particles in the filling fluid is 1-20%.

Further, the injection port and the extraction port are provided with filters.

Further, the injection port and/or the extraction port are provided with a flow control device.

Further, it also includes the following steps: (4) Recycling the dual-channel pipe string.

Further, the method for recovering the dual-fluid pipe string is as follows: (4.1) Establishing a flowback channel; (4.2) Injecting the back-drain liquid into the injection channel and/or production channel of the dual-fluid pipe string; (4.3) The packer particles are returned from the annulus to the wellhead; (4.4) a double-channel pipe string is extracted.

In order to achieve the above objective, the present invention also adopts the following technical solutions:

A completion structure for injection and production in the same well, comprising a double-channel pipe string arranged in a wellbore; the double-channel pipe string comprises an injection channel and a production channel, the injection channel is provided with one or more There are two injection ports, the production flow channel is provided with one or more production outlets, and the annulus between the double flow channel pipe string and the well wall is provided with a continuous packer formed by the accumulation of packing particles.

Further, the wellhead of the well is provided with a wellhead device or a Christmas tree; the casing annulus valve of the wellhead device or the Christmas tree is in a closed state, and the continuous packer is enclosed in the annulus.

Further, the heel end of the dual-fluid pipe string is provided with a packer with a packed channel; the packing port of the packer with a packed channel is in a closed state, and the continuous packer is enclosed in the annulus.

Further, the heel end of the double-fluid pipe string is provided with a liquid expansion packer to seal the continuous packer in the annulus.

Further, the packing particles are spherical or special-shaped structures made of polyethylene, polypropylene, polystyrene, polyvinyl chloride, nylon 66 or styrene-divinylbenzene cross-linked copolymer, and have a particle size of 50-300 meshes. The density is 0.8-1.4g/cm ³ .

Further, the injection port and the extraction port are provided with filters.

The present invention is a packing method and completion structure for injection and production in the same well. Compared with the traditional packer, the continuous packer is formed by the accumulation of particles during the filling, which can fill the entire section and seal and isolate It has good effect and strong spatial adaptability. Even if there are channeled casing perforated wells outside the casing, the invention can also realize the same well injection and production, which greatly expands the application range of the same well. In the process of running the pipe string, it is not hindered by the packer preset on the pipe string, and can directly use the existing equipment to run the pipe string up and down the well. The construction process is easy and there will be no problem of the packer jamming in the wellbore. . When the string is recovered, the packing particles can be returned to the outside of the wellhead, making the recovery of the string from impossible to possible.

Description of the drawings

Fig. 1 is a schematic flow chart of a packing method for injection-production in the same well according to the present invention;

Figure 2 is a schematic diagram of the overall structure and working process of a well completion structure used in the same well for injection and production of the present invention.

Description of Reference Signs: 1-surface; 2-wellhead seal; 3-casing; 4-cement ring; 5-casing annulus valve; 6-annulus; 7-injection string; 8-production string; 9-injection port; 10- mining outlet; 11-injection fracture; 12-production fracture; 13-continuous packer formed by packing particles in annulus.

Detailed ways

In the following, with reference to FIG. 1, a specific implementation of the isolation method and completion structure for the same well injection and production of the present invention will be further described. The isolation method and completion structure for the same well injection and production of the present invention are not limited to the description of the following embodiments.

Example 1:

This embodiment provides a packing method for injection and production in the same well.

As shown in Figure 1, it includes the following steps: (1) Run a dual-channel tubing string into the well; the dual-channel tubing string includes an injection channel and a production channel, and the injection channel is provided with one or more injection channels. Inlet, the production flow channel is provided with one or more production outlets; (2) Packing packing particles into the annulus between the double-flow channel pipe string and the well wall until the packing particles fill the annulus and accumulate to form a continuous seal Partition; (3) Close the annulus; so that the packing particles are fixed in the annulus to form a relatively stable structure to avoid the pressure difference and the flow of the packing particles when the flow channel is injected into the displacement medium during the production process It moves from the packing section to the direction of the wellhead, thereby destroying the continuous packer, resulting in the failure of the continuous packer's isolation between the injection and production sections; (4) After the end of production or when needed, the double-channel pipe string Recycling; specifically including the following steps: (4.1) Establishing a flowback channel; (4.2) Injecting the flowback fluid into the injection channel and/or production channel of the dual-fluid pipe string; (4.3) Removing the packer particles from the ring The air flows back to the outside of the wellhead; (4.4) a double-channel pipe string is extracted.

The working principle of this method is as follows: as shown in Figure 2, the wellbore vertically penetrates through multiple fractures (including artificial fractures or natural fractures); according to preset settings, some fractures are set as injection fractures, and the injection port corresponds to it, and some fractures It is set to produce a production crack, and the production outlet corresponds to it; at this time, each group of production outlets and adjacent injection ports form a group of injection-production units. If the adjacent injection port and the production outlet are not sealed and isolated, the displacement medium injected into the wellbore annulus from the injection port will directly pass through the wellbore annulus and flow to the production outlet, causing a "short circuit" between the injection port and the production outlet. According to the above technical solution, by filling the annulus with the packing particles and sealing them in the annulus, a continuous packer filled with the annulus is formed, thereby isolating the adjacent injection port and the mining outlet from each other and preventing the outflow from the injection port The displacement medium flows in the wellbore annulus, and it also allows the displacement medium to flow radially from the injection port to the injection fracture under the action of the pressure difference, and allows the displacement medium injected into the fracture to flow from the injection fracture under the pressure difference. Flow through the formation to the production fracture, and then flow from the production fracture to the production outlet. In the production process, under the effect of pressure difference, when the displacement medium enters the injection fracture, it will enter the formation of the injection-production unit and displace the oil and gas in the formation to the production fracture with lower pressure, and finally enter through the production outlet The runner is mined and mined.

In the technical solution of this embodiment, for different wellbore structures, different methods can be adopted to pack the packing particles to form a continuous packer, as follows: For wells with wellhead devices or Christmas trees at the wellhead, packing packing particles The method is: injecting the packing fluid carrying the packing particles into the annulus through the casing annulus channel of the wellhead device or the Christmas tree; the method of closing the annulus is: closing the casing annulus valve of the wellhead device or the Christmas tree. When recovering the double-fluid pipe string, only need to open the casing annulus valve to establish the flowback channel. During the production process, when the injection string is injecting the displacement medium, the annulus should be pressurized to no less than the injection pressure of the injection string to avoid the pressure at the injection port of the horizontal section being higher than the annulus pressure, so that the packing particles are directed towards the wellhead Directional movement destroys the sealing performance of the continuous packer. For wells that have been run into a dual-channel string and equipped with a fluid expansion packer at the heel end of the dual-channel string, the method of packing and packing particles is: directly injecting the packing fluid carrying the packing particles into the annulus from the wellhead; The method of the annulus is to close the annulus by a liquid-expandable packer installed at the heel end of the dual-channel pipe string. This technical solution uses a liquid expansion packer to seal the particles in the annulus. Since the liquid expansion packer does not have a flowback function, it is necessary to use drilling and other methods when recovering a dual-channel pipe string , Establish a flowback channel in the fluid expansion packer. For the well with a packing channel packer at the heel end of the dual-fluid pipe string; the method of packing and packing particles is: injecting the packing fluid carrying the packing particles into the annulus through the filling port of the packing channel packer; The method of closing the annulus is: closing the filling port of the packer with filling channel. When recovering the double-fluid pipe string, it is only necessary to open the packing port of the packing channel packer to establish the flowback channel. The above three technical solutions can easily realize the packing and flowback of the packed particles, and facilitate the running and recovery of the double-fluid pipe string.

In the technical solution of this embodiment, dual-fluid pipe strings of different structures can be used, for example, the double-layer concentric tubing or parallel dual tubing adopted in Chinese Patent CN201810104442.9. The advantage of using double-layer concentric tubing is that the overall shape of the tubing string is cylindrical, which is convenient for running into the wellbore. The technology and equipment for running the tubing string and raising the tubing string are very mature, and the existing packer can be used directly on the heel end. Closed; but the internal structure of the double-layer concentric tubing is more complicated, and the isolation between the inner and outer layers is difficult. The advantage of using double tubing is that the injection channel and the production channel can be established once the pipe is down, but because its cross-sectional shape is not circular, special down-pipe equipment is required for auxiliary construction. It is also possible to directly use two existing tubing pipes to be run into the well one after the other, respectively as the injection channel and the production channel. There is no need to customize the dual-fluid pipe string. When the pipe is run, the next one can be the next one, and the construction is relatively simple; However, this method is not easy to use conventional packers to seal the heel end.

In the technical solution of this embodiment, the method of filling the annulus with packing particles can refer to the international patent application (application number: PCT/CN2010/002014) named "Oil and Gas Well Production Section Anti-channeling Packing Particles, In the "Completion Method and Oil Production Method Using Such Particles" patent, the method of filling the annulus with packing particles is to inject the packing fluid carrying the packing particles into the annulus, so that the packing particles are accumulated in the annulus. Specifically, the filling fluid may be formation water, surface fresh water or seawater, and the volume ratio concentration of the packing particles in the filling fluid is 1-20%; the packing particles may be sand, sand, gravel, quartz sand , Ceramsite, hollow glass beads or fly ash; more preferably, the packing particles are polyethylene, polypropylene, polystyrene, polyvinyl chloride, nylon 66 or styrene Spherical or special-shaped structure of vinylbenzene cross-linked copolymer, particle size of 50-300 mesh, true density of 0.8-1.4g/cm ³ ; more preferably, the true density of the spacer particles is 1.00-1.10g/cm ^3. It is closer to the density of water to facilitate filling and flowback.

Preferably, in order to prevent the packed particles from entering the injection channel or the production channel through the inlet or the production outlet, it is necessary to adopt an injection port and a production outlet provided with a filter structure, and the filter adopts an outer protective cover Filter structure. In order to achieve simultaneous production of multiple fluid-producing sections in the wellbore, it is desirable that the injection flow rate of the displacement medium at each injection port and the fluid production flow rate at the production outlet be the same or uniform; or for the presence of large leakage fractures in the wellbore, avoid the displacement of the medium The large leakage is wasted in the cracks, and it is necessary to artificially reduce the displacement medium flow rate of the injection port and the production liquid flow rate of the production outlet; based on the above requirements, it is necessary to set the flow rate of each injection port and production outlet reasonably. The flow control device can be installed at the injection port and the production outlet; there are three installation methods for the flow control device, one is to install only at the injection port, the other is to install only at the production outlet, and the third is to install both at the injection port and the production outlet. The flow control device may be nozzles with different aperture sizes. As a more specific implementation, the injection flow channel or the production flow channel can be directly implemented by a water control screen in the prior art, including a water control screen that has no additional flow resistance function to the flow of water relative to oil. Pipes (ICD) and water control screens (AICD) with additional flow resistance to water relative to oil flow, etc.

Example 2:

This embodiment provides a well completion structure formed by the method described in Embodiment 1 for the same well injection and production. As shown in Figure 2, it includes a dual-channel pipe string arranged in the wellbore; the dual-channel pipe string includes an injection channel and a production channel, the injection channel is provided with one or more injection ports, and the production The outlet flow channel is provided with one or more mining outlets; the annulus between the double flow channel pipe string and the well wall is provided with a continuous packer formed by the accumulation of packing particles. The wellbore structure, double-fluid pipe string, and packing particles used in this embodiment are set with reference to Embodiment 1.

Example 3:

This embodiment provides a specific application of the technical solutions described in Embodiments 1 and 2.

As shown in Figure 2, an oil well with a thickness of 10 meters and a low-permeability formation with a permeability of only 1 millidarcy; the horizontal section of the well has a diameter of 8.5 inches and a horizontal section length of 1,000 meters. The production section of the horizontal section of the wellbore is an open hole. The wall and the horizontal section have 20 artificial fracturing fractures with an interval of about 50 meters between adjacent fractures. The 20 fracture intervals are set as injection fractures and production fractures, and the production section is divided into 10 injection-production units. Separate injection string and production string are run into the wellbore as the injection channel and production channel respectively; the injection string and production string are equipped with the corresponding positions of the injection and production fractures with flow control function Nozzle. The wellhead is provided with a wellhead device (not shown in the figure), the injection pipe string and the production pipe string are connected with the external pipeline of the wellhead device, and the annulus valve is connected with the wellhead device. (With reference to Fig. 2, the relevant content of the reference numerals will be explained.)

If the traditional packer method is used, at least 20 packers must be used. At the same time, in this embodiment, the injection string and the production string are arranged independently, and it is very difficult to seal and isolate the existing packer, because the relative positional relationship between the injection string and the production string in the downhole horizontal section is Arbitrarily, if it is a plane arrangement relationship, it may be a top-down arrangement relationship, or a twisted relative position relationship, etc., the packer not only needs to seal the outer circumference of the injection string and the outer circumference of the production string, but also seal the 8.5-inch open hole wall In this way, the isolation effect is poor. In addition, two strings with 20 packers need to be run in parallel at the same time. The possibility of jamming during the construction process is extremely high. In the future, it will also be used when 20 packers and injection-production strings are recovered. It will be very difficult.

This embodiment adopts the following steps to realize the sealing isolation between multiple injection ports and production outlets: (1) Insert 2 7/8 inch injection pipe string and production pipe string; specifically, use existing wellhead pipe string To run the equipment, first run the injection string with 10 injection ports to a suitable position, and then run the production string with 10 production ports to a suitable position; then, install the wellhead device at the wellhead. The two pipe strings are run separately, and the two pipe strings are run separately, and the two pipes are run in parallel at the same time, making the construction easier. (2) Through the casing annulus channel of the wellhead device, inject the packing fluid carrying the packing particles into the wellbore annulus until the packing particles fill the horizontal section annulus and accumulate to form a continuous packer with a length of 1000 meters; Yes, the filling fluid uses formation water, and the packing particles are made of spherical styrene-divinylbenzene cross-linked copolymer with a particle size of about 150 meshes and a true density of 1.05 g/cm ³ . (3) Close the casing annulus valve of the wellhead device to form a completion structure.

After the completion of the above-mentioned completion structure, water is injected from the wellhead and the pipe string is extracted from the wellhead to produce high-yield crude oil. In this embodiment, the isolation effect of a continuous packer with a length of 1000 meters provides a key role for high oil production flow. The continuous packer with a length of 1000 meters makes the entire horizontal section of the wellbore no channel for flow. The isolation effect of the continuous packer separates the entire horizontal section into 10 independent injection-production units, and each injection-production unit corresponds to a set of injection fractures and production fractures. The injected water of the injection string flows through the injection port to the injection fracture, and through the entire fracture surface, the injected water seeps to the production fracture surface, and the seepage of the injected water drives the formation oil to flow to the production fracture. The wall surface of the injected and produced fractures is 10 meters high, 150 meters long on one side and 300 meters long on both sides. The area of each crack is about 3000 square meters. This kind of seepage area is very large, which can greatly increase oil production. In addition, the distance between fractures is only 50 meters, and the displacement seepage distance in each injection-production unit is short, so that the oil production is further improved. During the injection process, 10 injection ports correspond to 10 fractures, all of which are injecting water, and 10 production outlets are injecting displaced oil. This horizontal well has 10 injection-production units producing at the same time, and the oil production rate is increased by 10 times. In this embodiment, the isolation effect of the continuous packer with a length of 1000 meters provides a key role for the high-yield oil flow of the horizontal well. The continuous packer continuously seals the horizontal section up to 1000 meters, avoiding the short circuit of the fluid flow between the injection port and the outflow port, so that the pressure difference between the injection port and the extraction port can be formed during the liquid injection process, so that the pressure of each flow unit There is an injection-production pressure difference on a pair of injection-production fracture surfaces, and the 1000-meter-long horizontal section is continuously sealed. At the same time, 10 injection-production flow units are established for simultaneous injection and simultaneous oil production.

The above content is a further detailed description of the present invention in combination with specific preferred embodiments, and it cannot be considered that the specific implementation of the present invention is limited to these descriptions. The technical scheme of the present invention is not only applicable to horizontal wells, but also to vertical wells or inclined wells; not only can the internal annulus of the wellbore be integrally filled to form a continuous packer, but also can only be used for the production section of the wellbore annulus or specific One or more sections of wellbore annulus are filled locally. During the production process, the injected displacement medium is usually water, which also includes nitrogen, carbon dioxide, dry gas, and rich gas, as well as other displacement agents that enhance oil recovery, such as polymer solutions and surfactant solutions. The fractures in the technical scheme of the present invention include natural fractures and artificial fractures, but should not be ruled out. The present invention can also be applied to wells without fractures. For those of ordinary skill in the technical field to which the present invention belongs, a number of simple deductions or substitutions can be made without departing from the concept of the present invention, and these should be regarded as belonging to the protection scope of the present invention.

Claims

A packing method for injection and production in the same well is characterized in that it comprises the following steps:

(1) Run a dual-channel pipe string into the well; the dual-channel pipe string includes an injection channel and a production channel, the injection channel is provided with one or more injection ports, and the production channel is provided with One or more mining outlets;

(2) Pack packing particles into the annulus between the double-fluid pipe string and the well wall until the packing particles fill the annulus and accumulate to form a continuous packer;

(3) Close the annulus.
The isolation method for same-well injection and production according to claim 1, wherein the wellhead of the well is provided with a wellhead device or a Christmas tree;

The method for packing and packing particles is: injecting a filling fluid carrying packing particles into the annulus through a casing annulus passage of a wellhead device or a Christmas tree;

The method for closing the annulus is: closing the wellhead device or the casing annulus valve of the Christmas tree.
The packing method for same well injection and production according to claim 1, characterized in that: the heel end of the double-fluid pipe string is provided with a packer with a filling channel;

The method for packing and packing particles is as follows: injecting a filling liquid carrying the packing particles into the annulus through a filling port of a packer with a packing channel;

The method for closing the annulus is: closing the filling port of the packer with a filling channel.
The packing method for same well injection and production according to claim 1, characterized in that: the heel end of the double-fluid pipe string is provided with a liquid-contact expansion packer;

The method for packing and packing particles is: injecting a filling fluid carrying packing particles into the annulus from the wellhead;

The method for closing the annulus is as follows: after the filling is completed, the liquid-expanded packer continues to expand to seal the annulus.
The isolation method for injection-production in the same well according to claim 1, wherein the isolation particles include sand, sand, quartz sand, gravel, ceramsite, hollow glass beads or fly ash. One or more.
The isolation method for same-well injection and production according to claim 1, wherein the isolation particles are polyethylene, polypropylene, polystyrene, polyvinyl chloride, nylon 66 or styrene divinylbenzene. The cross-linked copolymer has a spherical or special-shaped structure with a particle size of 50-300 mesh and a true density of 0.8-1.4 g/cm 3 .
The isolation method for same-well injection and production according to claim 1, wherein the method of filling the annulus with isolation particles is: injecting a filling fluid carrying the isolation particles into the annulus.
The isolation method for same-well injection and production according to claim 7, wherein the filling fluid is formation water, surface fresh water or seawater, and the volume ratio concentration of the isolation particles in the filling fluid is 1- 20%.
The isolation method for same well injection and production according to claim 1, characterized in that: the injection port and the production outlet are provided with filters.
The isolation method for injection-production in the same well according to claim 1, wherein the injection port and/or the production outlet is provided with a flow control device.
The isolation method for same well injection and production according to claim 1, characterized in that it further comprises the following steps: (4) recovering the dual-fluid pipe string.
The isolation method for same-well injection and production according to claim 11, characterized in that: the method for recovering the dual-channel pipe string is as follows:

(4.1) Establish flow-back channels;

(4.2) Inject flowback liquid into the injection channel and/or production channel of the dual-channel pipe string;

(4.3) Return the packer particles from the annulus to the wellhead;

(4.4) The double-channel pipe string is extracted from the upper part.
A completion structure for injection and production in the same well, comprising a double-channel pipe string arranged in a wellbore; the double-channel pipe string comprises an injection channel and a production channel, the injection channel is provided with one or more The production flow channel is provided with one or more production outlets, and is characterized in that: the annulus between the double flow channel pipe string and the well wall is provided with a continuous packer formed by the accumulation of packing particles .
The completion structure for same-well injection and production according to claim 13, characterized in that: the wellhead of the well is provided with a wellhead device or a Christmas tree; the casing annulus valve of the wellhead device or the Christmas tree is closed State, the continuous packer is enclosed in the annulus.
The completion structure for same well injection and production according to claim 13, characterized in that: the heel end of the dual-fluid pipe string is provided with a packer with a packed channel; the packer with a packed channel The mouth is closed, and the continuous packer is enclosed in the annulus.
The completion structure for the same well injection and production according to claim 13, characterized in that: the heel end of the double-fluid pipe string is provided with a fluid expansion packer to seal the continuous packer in the annulus.
The completion structure for injection and production in the same well according to claim 13, wherein the packing particles include sand, sand, quartz sand, gravel, ceramsite, hollow glass beads or fly ash. One or more.
The completion structure for same-well injection and production according to claim 13, characterized in that the packing particles are polyethylene, polypropylene, polystyrene, polyvinyl chloride, nylon 66 or styrene divinylbenzene The cross-linked copolymer has a spherical or special-shaped structure with a particle size of 50-300 mesh and a true density of 0.8-1.4 g/cm 3 .
The completion structure for the same well injection and production according to claim 13, wherein the injection port and the production outlet are provided with filters.
The completion structure for same well injection and production according to claim 13, characterized in that: the injection port and/or the production outlet is provided with a flow control device.