Heavy oil in-situ low-temperature oxidation channeling sealing method

Abstract

The invention provides a thick oil in-situ low-temperature oxidation channeling sealing method. The method comprises the steps that S10, a dominant channel or a steam channeling channel between an injection well and a production well around the injection well is determined; s20, determining the temperature range T1 to T2 of low-temperature oxidation coking of the production well which has a dominant channel or a steam channeling channel with the injection well; s30, testing the bottom hole temperature T and the bottom hole pressure P of the production well having the dominant channel or the steam channeling channel with the injection well, and selecting a corresponding plugging method for plugging according to the bottom hole temperature T and the bottom hole pressure P; and S40, detecting the production well which has a dominant channel or a steam channeling channel with the injection well so as to determine the plugging effect. The problems that in the prior art, after a steam channeling channel is blocked, the temperature resistance is poor, and the blocking cost is high are solved.

Description

Technical Field

[0001] The invention relates to the technical field of heavy oil development, and in particular to a method for sealing heavy oil in-situ low-temperature oxidation. Background Art

[0002] In the process of oilfield development, three generations of technological revolutions have been experienced, including steam huff-and-puff, steam flooding, SAGD (steam-assisted gravity drainage) + fire flooding, to achieve comprehensive utilization of ordinary heavy oil, extra-heavy oil and super-heavy oil. Due to formation heterogeneity, steam overburden and other reasons, with the continuous injection of steam, serious steam channeling problems will occur. Therefore, the development of efficient methods to control steam channeling is crucial to the uniform utilization of oil reservoirs and the improvement of recovery.

[0003] Since the early 1990s, research has been conducted on the use of tannin extracts, alkali lignin, etc. to prepare temperature-resistant gels to prevent steam channeling. Among the three types of materials, tannin extracts, alkali lignin, and lignin, tannin extracts have the best gelling properties, the best gel stability, and the highest gel strength. It is the most commonly used plugging material for plugging steam channeling in China in the early days. However, with the rise in tannin extract prices in recent years, its application in oil fields has been limited. Another cross-linked polymer used to plug steam channeling is phenolic gel prepared from synthetic polymers. The earlier cross-linking agents were phenol and formaldehyde, which were later gradually replaced by a combination system of hydroquinone and hexamethylenetetramine or water-soluble phenolic resin. The temperature resistance of this type of gel mainly depends on the use of polymers and fillers. The gelling time of polymers used as gelling agents at 200°C is less than 1 hour, which is difficult to meet the requirements of plugging steam channeling in deep formations during thermal recovery. Therefore, it is necessary to propose a low-cost, high-efficiency, and temperature-resistant steam channel plugging method to overcome the defects in the existing technology, improve the uniform utilization of the oil layer, and achieve the purpose of increasing production and efficiency. Summary of the invention

[0004] The main purpose of the present invention is to provide a method for blocking heavy oil in-situ low-temperature oxidation, so as to solve the problems of poor temperature resistance and high blocking cost after blocking the steam channel in the prior art.

[0005] In order to achieve the above-mentioned object, according to one aspect of the present invention, a method for plugging heavy oil in-situ low-temperature oxidation, comprising: step S10: determining a dominant channel or steam channeling channel between an injection well and production wells around the injection well; step S20: determining a temperature range T1 to T2 for low-temperature oxidation coking of the production well having a dominant channel or steam channeling channel with the injection well; step S30: testing the bottom hole temperature T and the bottom hole pressure P of the production well having a dominant channel or steam channeling channel with the injection well, and selecting a corresponding plugging method for plugging according to the bottom hole temperature T and the bottom hole pressure P; step S40: testing the production well having a dominant channel or steam channeling channel with the injection well to determine the plugging effect.

[0006] Furthermore, step S10 includes: injecting a marker substance into the injection well; regularly monitoring and recording the parameters and output components of the injection well and the production wells around the injection well; when the parameters of one or more production wells around the injection well show a linkage reaction with the parameters of the injection well or the marker substance is detected in the output of the production well, it proves that there is a dominant channel or a steam channel between the one or more production wells and the injection well; and determining the position of the dominant channel or the steam channel in relationship to the oil layer and the dynamic liquid level of the production well.

[0007] Furthermore, in determining the positional relationship between the dominant channel or steam channeling channel and the oil layer and dynamic liquid level of the production well, the positional relationship between the dominant channel or steam channeling channel and the oil layer and dynamic liquid level of the production well is determined by a method of finding channeling by lowering a packer and / or a method of measuring the dynamic liquid level.

[0008] Further, in step S10, the production wells around the injection well include production wells within a range of 50 meters to 200 meters from the injection well.

[0009] Furthermore, step S20 includes: sampling a production well having a dominant channel or a steam channel with the injection well; and measuring the temperature range T1 to T2 of low-temperature oxidation coking under the oil layer temperature and oil layer pressure indoors.

[0010] Furthermore, in the process of sampling the production well having a dominant channel or a steam channel with the injection well, the production well having a dominant channel or a steam channel with the injection well is sampled multiple times.

[0011] Furthermore, in the process of measuring the temperature range T1 to T2 of low-temperature oxidation coking under the oil layer temperature and oil layer pressure, an average value of the low-temperature oxidation temperatures measured multiple times is calculated.

[0012] Further, step S30 includes: if the bottom hole temperature T satisfies T1<T<T2, a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the injection well, and the bottom hole pressure P is controlled to remain unchanged, so as to form low-temperature coke and seal the gas channeling layer; if the bottom hole temperature T satisfies T<T1 or T>T2, the temperature in the steam channeling channel is adjusted to be between T1 and T2, and a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the injection well, and the bottom hole pressure P is controlled to remain unchanged, so as to seal the gas channeling layer.

[0013] Furthermore, if the bottom hole temperature T satisfies T<T1 or T>T2, the temperature in the steam channeling channel is adjusted to be between T1 and T2, and the injection well injects a first preset volume of crude oil containing heavy components and a second preset volume of air, while controlling the bottom hole pressure P to remain unchanged. The process of plugging the gas channeling layer includes: if the bottom hole temperature T satisfies T<T1, the first preset volume of crude oil containing heavy components and the second preset volume of air are injected from the injection well, and high-temperature steam of a preset temperature is injected from the production well to control the temperature in the steam channeling channel to be between T1 and T2, while controlling the bottom hole pressure P to remain unchanged, forming low-temperature coke, and plugging the gas channeling layer; if the bottom hole temperature T satisfies T>T2, the first preset volume of crude oil containing heavy components and the second preset volume of air are injected from the injection well, and the third preset volume of normal temperature clean water is injected from the production well to control the temperature in the steam channeling channel to be between T1 and T2, while controlling the bottom hole pressure P to remain unchanged, causing a low-temperature oxidation reaction, generating dense coke, and plugging the gas channeling layer.

[0014] Further, step S40 includes: injecting a marker substance into the injection well, and regularly detecting and recording the injection well; regularly monitoring and recording the parameters and output components of the injection well and the production wells around the injection well; if the production well no longer has a linkage reaction or the reaction is greatly weakened or the marker substance is no longer detected, the plugging is successful, otherwise the plugging fails.

[0015] By applying the technical solution of the present invention, the method for blocking heavy oil in-situ low-temperature oxidation includes: step S10: determining the dominant channel or steam channeling channel between the injection well and the production wells around the injection well; step S20: determining the temperature range T1 to T2 of low-temperature oxidation coking of the production well with the dominant channel or steam channeling channel with the injection well; step S30: testing the bottom hole temperature T and the bottom hole pressure P of the production well with the dominant channel or steam channeling channel with the injection well, and selecting a corresponding blocking method for blocking according to the bottom hole temperature T and the bottom hole pressure P; step S40: detecting the production well with the dominant channel or steam channeling channel with the injection well to determine the blocking effect.

[0016] The dominant channel or steam channel between the injection well and the surrounding production wells is determined to determine the location of the plugging, and then the temperature range of the low-temperature oxidation coking of the production well is determined, and the bottom hole temperature T and the bottom hole pressure P of the production well are measured at the same time. According to the measured bottom hole temperature T and the bottom hole pressure P, a suitable plugging method is selected to utilize the in-situ physical and chemical reaction of crude oil to generate coke with a certain plugging capacity, reduce the degree of steam channeling, improve the uniform utilization of the oil layer, improve the development effect of the oil reservoir, and improve the recovery degree, which has important practical significance for the thermal development of extra-heavy oil and super-heavy oil reservoirs. The method of in-situ low-temperature oxidation plugging of heavy oil in this application has low cost, high plugging efficiency and good temperature resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 A schematic flow chart of a method for sealing heavy oil in-situ low-temperature oxidation according to an optional embodiment of the present invention is shown;

[0019] Figure 2 The figure shows the position distribution diagram between the injection well and the production well according to the first embodiment of the present invention;

[0020] Figure 3 A flow chart of a method for in-situ low-temperature oxidation sealing of heavy oil according to embodiment 1 of the present invention is shown.

[0021] The above drawings include the following reference numerals:

[0022] 10. Injection well; 20. Production well. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0025] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0026] In order to solve the problems of poor temperature resistance and high plugging cost after plugging of steam channeling in the prior art, the present invention provides a method for plugging heavy oil channeling by in-situ low-temperature oxidation.

[0027] like Figures 1 to 3As shown, the method for blocking heavy oil in-situ low-temperature oxidation includes: step S10: determining the dominant channel or steam channeling channel between the injection well 10 and the production well 20 around the injection well 10; step S20: determining the temperature range T1 to T2 of low-temperature oxidation coking of the production well 20 with the dominant channel or steam channeling channel with the injection well 10; step S30: testing the bottom hole temperature T and the bottom hole pressure P of the production well 20 with the dominant channel or steam channeling channel with the injection well 10, and selecting a corresponding blocking method for blocking according to the bottom hole temperature T and the bottom hole pressure P; step S40: detecting the production well 20 with the dominant channel or steam channeling channel with the injection well 10 to determine the blocking effect.

[0028] The dominant channel or steam channel between the injection well 10 and the surrounding production wells 20 is determined to determine the location of the plugging, and then the temperature range of the low-temperature oxidation coking of the production well 20 is determined, and the bottom hole temperature T and the bottom hole pressure P of the production well 20 are measured at the same time. According to the measured bottom hole temperature T and the bottom hole pressure P, a suitable plugging method is selected to utilize the in-situ physical and chemical reaction of crude oil to generate coke with a certain plugging ability, reduce the degree of steam channeling, improve the uniform utilization of the oil layer, improve the development effect of the oil reservoir, and improve the recovery degree, which has important practical significance for the thermal development of extra-heavy oil and super-heavy oil reservoirs. The method of in-situ low-temperature oxidation plugging of heavy oil in this application has low cost, high plugging efficiency, and good temperature resistance.

[0029] Specifically, step S10 includes: injecting a marker substance into the injection well 10; regularly monitoring and recording the parameters and output components of the injection well 10 and the production wells 20 surrounding the injection well 10; when the parameters of one or more production wells 20 surrounding the injection well 10 react in a linkage reaction with the parameters of the injection well 10 or the marker substance is detected in the output of the production well 20, it is proved that there is a dominant channel or a steam channel between one or more production wells 20 and the injection well 10; and determining the position relationship between the position of the dominant channel or the steam channel and the oil layer and the dynamic liquid level of the production well 20. After the marker substance is injected into the injection well 10, the parameters and output components of the injection well 10 and the surrounding production wells 20 are regularly monitored to determine which production wells 20 have a dominant channel or a steam channel between them and the injection well 10, and determine the position relationship between the position of the dominant channel or the steam channel and the oil layer and the dynamic liquid level of the production well 20, so as to facilitate the subsequent measurement of the temperature range of low-temperature oxidation coking.

[0030] If the position of the dominant channel or the steam channel is above the dynamic liquid level, crude oil needs to be injected from the production well 20 for coking reaction. If the position of the dominant channel or the steam channel is below the dynamic liquid level, crude oil does not need to be injected, or the first preset volume of the injected first preset volume of crude oil is zero.

[0031] It should be noted that regular monitoring refers to monitoring at a preset cycle.

[0032] Specifically, in determining the positional relationship between the dominant channel or steam channel and the oil layer and dynamic liquid level of the production well 20, the positional relationship between the dominant channel or steam channel and the oil layer and dynamic liquid level of the production well 20 is determined by the method of finding channeling by lowering a packer and / or the method of measuring the dynamic liquid level.

[0033] Specifically, in step S10, the production wells 20 around the injection well 10 include production wells 20 within a range of 50 meters to 200 meters from the injection well 10. Production wells 20 within a range of 50 meters to 200 meters from the injection well can be used as production wells 20 for regular monitoring, and the specific range can be selected according to actual conditions.

[0034] Specifically, step S20 includes: sampling the production well 20 having a dominant channel or a steam channel with the injection well 10; measuring the temperature range T1 to T2 of low-temperature oxidation coking under the oil layer temperature and oil layer pressure indoors. After sampling, the sample is tested under the indoor temperature of the oil layer temperature and the indoor pressure of the oil layer pressure to test the temperature range of low-temperature oxidation coking of the sample.

[0035] Specifically, in the process of sampling the production well 20 having a dominant channel or a steam channel with the injection well 10 , the production well 20 having a dominant channel or a steam channel with the injection well 10 is sampled multiple times.

[0036] Specifically, in the process of measuring the temperature range T1 to T2 of low-temperature oxidation coking under the oil layer temperature and oil layer pressure, the average value of the low-temperature oxidation temperatures measured multiple times is calculated. The oil layer temperature and oil layer pressure refer to the temperature and pressure at the location of the dominant channel or the steam channel. In other words, it is necessary to simulate the temperature environment and pressure environment at the location of the dominant channel or the steam channel, and obtain the temperature range of low-temperature oxidation coking of the sample under this environment.

[0037] When each sample is tested, a temperature range for low-temperature oxidation to coke is obtained, and finally the temperature ranges for low-temperature oxidation to coke of multiple samples are averaged.

[0038] Specifically, step S30 includes: if the bottom hole temperature T satisfies T1<T<T2, a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the injection well 10, and the bottom hole pressure P is controlled to remain unchanged, so as to form low-temperature coke and seal the gas channeling layer; if the bottom hole temperature T satisfies T<T1 or T>T2, the temperature in the steam channeling channel is adjusted to be between T1 and T2, and the injection well 10 injects a first preset volume of crude oil containing heavy components and a second preset volume of air, and the bottom hole pressure P is controlled to remain unchanged to seal the gas channeling layer.

[0039] It should be noted that during the plugging process, dense coke is generated, and the coke slug volume Qj The through pore volume Q is 10% to 15% c , the volume of the pores through the channel is Q c =kπR 2 hФ, where K is the correction factor, generally 0.3-0.5 (because steam channeling is mainly part of the large pores, not the entire oil layer), R is the average plugging radius, generally 1.5-2m; h is the plugging layer thickness; Ф is the average porosity of the oil layer. The first preset volume of crude oil Q y =1800Q j / (985*0.08), the second preset volume Q of air k =180Q j / 2.4, where Q j , Q c , Q y , Q k The unit is m 3 The through pores refer to the dominant channels or steam through channels.

[0040] It should be noted that R is the average plugging radius, which is centered on the channel. The coke slug is a cylinder with a radius of R. h is the thickness of the plugging layer (the layer where the steam channel is located). After the steam channel is determined, the geological data is consulted to obtain this thickness value.

[0041] Specifically, if the bottom hole temperature T satisfies T<T1 or T>T2, the temperature in the steam channeling channel is adjusted to be between T1 and T2, and the injection well 10 injects a first preset volume of crude oil containing heavy components and a second preset volume of air, while controlling the bottom hole pressure P to remain unchanged. The process of plugging the gas channeling layer includes: if the bottom hole temperature T satisfies T<T1, the first preset volume of crude oil containing heavy components and the second preset volume of air are injected from the injection well 10, and high-temperature steam of a preset temperature is injected from the production well 20 to control the temperature in the steam channeling channel to be between T1 and T2, while controlling the bottom hole pressure P to remain unchanged, forming low-temperature coke, and plugging the gas channeling layer; if the bottom hole temperature T satisfies T>T2, the first preset volume of crude oil containing heavy components and the second preset volume of air are injected from the injection well 10, and the third preset volume of normal temperature clean water is injected from the production well 20 to control the temperature in the steam channeling channel to be between T1 and T2, while controlling the bottom hole pressure P to remain unchanged, causing a low-temperature oxidation reaction, generating dense coke, and plugging the gas channeling layer. By adjusting the bottom hole temperature to the range of T1 to T2, after introducing crude oil and air, the dominant channel or steam channel is oxidized in a low temperature environment to form dense coke. The porosity, permeability and other parameters of the coke are significantly reduced compared with the original oil layer, thereby blocking the dominant channel and steam channel, reducing steam channeling and improving the uniform utilization of the oil layer.

[0042] Among them, high-temperature steam refers to steam with a temperature between 200°C and 300°C. Normal-temperature clean water refers to clean water within the range of 20°C to 30°C.

[0043] Specifically, step S40 includes: injecting a marker substance into the injection well 10, regularly detecting and recording the injection well 10; regularly monitoring and recording the parameters and output components of the injection well 10 and the production wells 20 around the injection well 10; if the production well 20 no longer has a linkage reaction or the reaction is greatly weakened or the marker substance is no longer detected, the plugging is successful, otherwise the plugging fails. After the coke is formed, the plugging effect needs to be verified to determine whether the plugging is successful. If the plugging is unsuccessful, repeat the above steps until the plugging is successful.

[0044] The following is a detailed description with reference to a specific embodiment.

[0045] Embodiment 1

[0046] The well locations of the injection well 10 and the surrounding production wells 20 are shown in Figure 2 As shown, in Figure 2 Among them, well h000 is injection well 10, well h001 is production well No. 1, well h002 is production well No. 2, well h003 is production well No. 3, well h004 is production well No. 4, well h005 is production well No. 5, well h006 is production well No. 6, and the row spacing is between 50 meters and 150 meters. The method of in-situ low-temperature oxidation sealing of heavy oil is as follows:

[0047] Step 1: Inject de-oiled hot water or isotopes into well h000, and regularly monitor and record the parameters and output composition of well h000 and surrounding wells h001 to h006;

[0048] When the parameters of production wells 20 around the injection well 10, such as well H001, show a linkage reaction with the injection parameters of the injection well 10, or injected substances such as isotopes are detected in the output of well H001, it means that a dominant channel or a steam channel exists between well H001 and well H000, and the position of the dominant channel or the steam channel and its relationship with the oil layer and the dynamic liquid level of well H001 should be determined by methods such as lowering a packer to find channeling and measuring the dynamic liquid level.

[0049] Step 2: Determine the temperature of low-temperature oxidation coking for sealing channeling. For well h001 which has a dominant channel or steam channel with injection well 10, take samples three times, and measure the low-temperature oxidation coking temperature range T1-T2 under the reservoir temperature and reservoir pressure in indoor experiments. Calculate the average value of the three measured low-temperature oxidation temperatures.

[0050] Step 3: The bottom hole temperature and bottom hole pressure of the h001 well are tested to obtain the bottom hole temperature T and the bottom hole pressure P. If T1<T<T2, a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the h000 well, and the bottom hole pressure is controlled to be P, so as to form low-temperature coke and plug the gas channeling layer; if T<T1, a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the h000 well, and high-temperature steam of a preset temperature is injected from the h001 well, and the temperature in the steam channeling channel is controlled to be between T1-T2, and the bottom hole pressure is controlled to be P, so as to form low-temperature coke and plug the gas channeling layer; if T>T2, a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the h000 well, and a third preset volume of normal temperature clean water is injected from the h001 well, and the temperature in the steam channeling channel is controlled to be between T1-T2, and the bottom hole pressure is controlled to be P, so as to form dense coke and plug the gas channeling layer.

[0051] While determining the steam channeling channels in heavy oil reservoirs, a new method for blocking the steam channeling channels is provided. It has the characteristics of low cost, high efficiency and good temperature resistance. It can be used as an important supporting technology for thermal recovery of extra-heavy oil and super-heavy oil, and also provides strong support for the development of similar oil reservoirs, thereby reducing the degree of steam channeling, improving the uniform utilization of oil layers, and improving the development effect of oil reservoirs.

[0052] The present invention proposes a method for solving steam channeling by utilizing in-situ physicochemical reaction of crude oil after steam channeling in heavy oil reservoirs, which fills the gap that cannot be achieved by the prior art, has the characteristics of low cost, high efficiency and good temperature resistance, and can provide a theoretical basis for improving the uniform utilization degree of oil layers, improving the development effect of oil reservoirs, and increasing the recovery degree.

[0053] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0054] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0055] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for sealing heavy oil in-situ low-temperature oxidation, characterized in that: include: Step S10: determining a dominant channel or a steam channel between the injection well (10) and the production wells (20) surrounding the injection well (10); Step S20: determining a temperature range T1 to T2 for low-temperature oxidation coking of the production well (20) having a dominant channel or a steam channel with the injection well (10); Step S30: testing the bottom hole temperature T and the bottom hole pressure P of the production well (20) having a dominant channel or a steam channel with the injection well (10), and selecting a corresponding plugging method for plugging according to the bottom hole temperature T and the bottom hole pressure P; Step S40: Detecting the production well (20) having a dominant channel or a steam channel with the injection well (10) to determine the plugging effect.

2. The method for sealing heavy oil in-situ low-temperature oxidation according to claim 1, characterized in that: The step S10 includes: Injecting a marker substance into the injection well (10); Regularly monitoring and recording the parameters and output components of the injection well (10) and the production wells (20) surrounding the injection well (10); When the parameters of one or more of the production wells (20) around the injection well (10) show a linkage reaction with the parameters of the injection well (10) or the marker substance is detected in the output of the production well (20), it is proved that there is a dominant channel or a steam channel between the one or more production wells (20) and the injection well (10); The positional relationship between the position of the dominant channel or the steam channel and the oil layer and the dynamic liquid level of the production well (20) is determined.

3. The method for sealing heavy oil in-situ low-temperature oxidation according to claim 2, characterized in that: In the process of determining the positional relationship between the position of the dominant channel or the steam channel and the oil layer and the dynamic liquid level of the production well (20), the positional relationship between the position of the dominant channel or the steam channel and the oil layer and the dynamic liquid level of the production well (20) is determined by a method of finding channeling by lowering a packer and / or a method of measuring the dynamic liquid level.

4. The method for sealing heavy oil in-situ low-temperature oxidation according to claim 1, characterized in that: In the step S10, the production wells (20) around the injection well (10) include the production wells (20) within a range of 50 meters to 200 meters from the injection well (10).

5. The method for sealing heavy oil in-situ low-temperature oxidation according to claim 1, characterized in that: The step S20 includes: Sampling the production well (20) having a dominant channel or a steam channel with the injection well (10); The temperature range of low temperature oxidation coking under the oil layer temperature and oil layer pressure is measured indoors, which is from T1 to T2.

6. The method for sealing heavy oil in-situ low-temperature oxidation according to claim 5, characterized in that: In the process of sampling the production well (20) having a dominant channel or a steam channel with the injection well (10), the production well (20) having a dominant channel or a steam channel with the injection well (10) is sampled multiple times.

7. The method for sealing heavy oil in-situ low-temperature oxidation according to claim 6, characterized in that: In the process of measuring the temperature range T1 to T2 of low-temperature oxidation coking under the oil layer temperature and oil layer pressure indoors, an average value of the low-temperature oxidation temperatures measured multiple times is calculated.

8. The method for sealing heavy oil in-situ low-temperature oxidation according to any one of claims 1 to 7, characterized in that: The step S30 comprises: If the bottom hole temperature T satisfies T1<T<T2, a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the injection well (10), while the bottom hole pressure P is controlled to remain unchanged, so as to form low-temperature coke and seal the gas channeling layer; If the bottom hole temperature T satisfies T<T1 or T>T2, the temperature in the gas channel is adjusted to be between T1 and T2, and the injection well (10) injects a first preset volume of crude oil containing heavy components and a second preset volume of air, while controlling the bottom hole pressure P to remain unchanged, thereby blocking the gas channeling layer.

9. The method for sealing heavy oil in-situ low-temperature oxidation according to claim 8, characterized in that: If the bottom hole temperature T satisfies T<T1 or T>T2, the temperature in the gas channeling channel is adjusted to be between T1 and T2, the injection well (10) injects a first preset volume of crude oil containing heavy components and a second preset volume of air, and at the same time controls the bottom hole pressure P to remain unchanged, and the process of plugging the gas channeling layer includes: If the bottom hole temperature T satisfies T<T1, a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the injection well (10), and high-temperature steam of a preset temperature is injected from the production well (20) to control the temperature in the steam channeling channel to be between T1 and T2, and at the same time control the bottom hole pressure P to remain unchanged, so as to form low-temperature coke and block the gas channeling layer; If the bottom hole temperature T satisfies T>T2, a first preset volume of crude oil containing heavy components and a second preset volume of air are injected from the injection well (10), and a third preset volume of clean water at room temperature is injected from the production well (20) to control the temperature in the steam channeling channel to be between T1 and T2, and at the same time control the bottom hole pressure P to remain unchanged, so that a low-temperature oxidation reaction occurs, dense coke is generated, and the gas channeling layer is blocked.

10. The method for sealing heavy oil in-situ low-temperature oxidation according to any one of claims 1 to 7, characterized in that: The step S40 comprises: Injecting a marker substance into the injection well (10), and regularly detecting and recording the injection well (10); Regularly monitoring and recording the parameters and output components of the injection well (10) and the production wells (20) surrounding the injection well (10); If the production well (20) no longer shows a linkage reaction or the reaction is greatly weakened or the marker substance is no longer detected, the plugging is successful; otherwise, the plugging fails.

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