SAGD (Steam Assisted Gravity Drainage) injection and production method and device for deep super heavy oil reservoir and computer equipment

Abstract

The embodiment of the invention provides a deep super heavy oil reservoir SAGD injection and production method and device and computer equipment, the method comprises the steps that a horizontal well and vertical wells in a vertical and horizontal combined well pattern are preheated, the vertical and horizontal combined well pattern comprises one horizontal well and a plurality of vertical wells, and the vertical wells are symmetrically distributed on the two sides of the horizontal well; judging whether preheating treatment is completed or not; and when preheating treatment is completed, steam is injected into at least part of the multiple vertical wells in turns, and SAGD oil extraction is conducted through the horizontal wells. According to the method provided by the embodiment of the invention, heat loss caused by burial depth during exploitation of the deep super heavy oil reservoir can be made up; the rising speed and overlying height of the steam cavity of an individual steam injection well point are effectively controlled, steam single-point breakthrough is prevented, and development of the steam cavity is improved; exploiting of the deep super heavy oil reservoir is achieved, and the recovery rate of the deep-layer-like oil reservoir is greatly guaranteed.

Description

Technical Field

[0001] The embodiments of this specification relate to the field of oil reservoir development technology, and in particular to a SAGD injection and production method, device and computer equipment for deep super heavy oil reservoirs. Background Art

[0002] SAGD (Steam Assisted Gravity Drainage) development technology is a cutting-edge technology for developing super-heavy oil. Its production mechanism is as follows: high-dryness steam is injected into the steam injection well, and the steam overlaps upward in the formation to form a steam chamber, which expands upward and laterally to exchange heat with the crude oil in the oil layer; the heated and reduced-viscosity crude oil and steam condensate rely on gravity to be produced in the horizontal production well below, and the steam chamber continues to expand and continuously occupies the volume of crude oil. This technology has been successfully implemented in super-heavy oil reservoirs and has achieved good development results, greatly reversing the situation of continuous decrease in annual oil production due to steam throughput. It has a high oil production rate and low production cost, and is considered to be one of the thermal recovery development technologies with the highest recovery rate.

[0003] However, deep (referring to those buried below 1000 to 1500 meters in the formation) ultra-heavy oil reservoirs generally adopt the huff-and-puff development method due to their depth. The recovery rate of this development method is only 25%, which has huge potential for increased production. Under the existing steam injection and insulation process conditions, the bottom hole steam dryness can only reach 40% at a well depth of 1500 meters; the edge and bottom water pressure of deep oil reservoirs is high, and high steam chamber pressure operation is required to balance the edge and bottom water and prevent water intrusion, resulting in the deep SAGD effectively heating the oil layer less than half of the shallow layer, and it is difficult to effectively form a steam chamber; after high-cycle steam huff-and-puff development, the oil layer is seriously heterogeneous, and after switching to SAGD steam injection, the steam chamber quickly rises to the top of the oil, and it is difficult to expand the steam chamber evenly. In other words, the existing SAGD development method is difficult to apply to the development and injection of deep ultra-heavy oil reservoirs.

[0004] In view of this, the present specification aims to provide a SAGD injection and production method, device and computer equipment for deep ultra-heavy oil reservoirs. Summary of the invention

[0005] In view of the above problems in the prior art, the purpose of the embodiments of this specification is to provide a SAGD injection and production method, device and computer equipment for deep ultra-heavy oil reservoirs to solve the problem that the existing SAGD reservoir development injection and production methods are difficult to apply to deep ultra-heavy oil reservoirs.

[0006] In order to solve the above technical problems, the specific technical solutions of the embodiments of this specification are as follows:

[0007] In a first aspect, the embodiments of this specification provide a SAGD injection and production method for a deep ultra-heavy oil reservoir, comprising:

[0008] Preheating the horizontal wells and vertical wells in a straight-horizontal combination well pattern, wherein the straight-horizontal combination well pattern includes a horizontal well and a plurality of vertical wells, wherein the plurality of vertical wells are symmetrically distributed on both sides of the horizontal well;

[0009] Determining whether the preheating treatment is completed;

[0010] When the preheating treatment is completed, steam is injected into at least part of the plurality of vertical wells in rotation, and the horizontal wells are used to switch to SAGD oil production.

[0011] In some preferred embodiments, the plurality of vertical wells include at least two first vertical wells and at least two second vertical wells, the first vertical wells and the second vertical wells located on the same side of the horizontal well are alternately arranged, and a pair of vertical wells symmetrically separated on both sides of the horizontal well are the first vertical well and the second vertical well respectively; the step of alternately injecting steam into at least part of the plurality of vertical wells includes:

[0012] Steam is injected into all the first vertical wells or all the second vertical wells in rotation for a preset time respectively until the oil production of the horizontal well is completed or a preset rotation round is reached.

[0013] In some preferred embodiments, after the preheating treatment is completed, steam is injected into at least part of the plurality of vertical wells in turn, and the horizontal wells are used to switch to SAGD oil production, including:

[0014] adjusting injection parameters when rotating steam injection into at least a portion of the plurality of vertical wells; and

[0015] The production parameters when converting the horizontal well to SAGD oil production are adjusted.

[0016] In some preferred embodiments, the injection parameters include at least the steam quality, injection rate and injection period of the injected steam, and the production parameters include at least the production-injection ratio and the operating pressure of the steam chamber formed between the horizontal well and the vertical well.

[0017] In some preferred embodiments, adjusting the injection parameters when rotating the steam injection into at least part of the plurality of vertical wells, and adjusting the production parameters when switching to SAGD oil production using the horizontal wells, further comprises:

[0018] Conduct sensitivity analysis on various injection parameters and production parameters;

[0019] According to the results of sensitivity analysis, determine the order of adjustment between various injection parameters and various production parameters;

[0020] The injection parameters and production parameters are adjusted according to the sequence.

[0021] In some preferred embodiments, the steam dryness is adjusted to be greater than 65%, the steam injection rate is adjusted to 120-140 t / d, the production-injection ratio is adjusted to 1.2, the operating pressure is adjusted to 4.5-6 MPa, and the steam injection cycle is adjusted to 2-3 months.

[0022] In some preferred embodiments, determining whether the preheating treatment is completed further includes:

[0023] Acquiring the interwell temperature and interwell formation pressure between the horizontal well and the vertical well;

[0024] Determining whether the inter-well temperature has reached a preset temperature and whether the inter-well formation pressure has reached a preset pressure;

[0025] If yes, the preheating process is complete.

[0026] In some preferred embodiments, determining whether the preheating treatment is completed further includes:

[0027] Obtaining the underground temperature field distribution between the horizontal well and the vertical well through oil well temperature measurement results and / or numerical simulation methods;

[0028] According to the temperature field distribution, determining whether the horizontal well and the vertical well are thermally connected;

[0029] If yes, the preheating process is complete.

[0030] In some preferred embodiments, determining whether the preheating treatment is completed further includes:

[0031] Obtaining the crude oil viscosity of the deep ultra-heavy oil reservoir;

[0032] Determining whether the viscosity of the crude oil is less than or equal to a preset viscosity threshold;

[0033] If yes, the preheating process is complete.

[0034] In some preferred embodiments, determining whether the preheating treatment is completed includes:

[0035] Acquire the recovery degree of the deep super-heavy oil reservoir after the horizontal well and the vertical well complete the current round of preheating during the preheating process;

[0036] Determining whether the recovery degree is greater than a preset recovery degree threshold;

[0037] If yes, then obtaining the interwell temperature and interwell formation pressure between the horizontal well and the vertical well;

[0038] Determining whether the inter-well temperature has reached a preset temperature and whether the inter-well formation pressure has reached a preset pressure;

[0039] If yes, the preheating treatment is completed;

[0040] If not, the horizontal well and the vertical well continue to be preheated.

[0041] In some preferred embodiments, the horizontal wells and vertical wells in the vertical-horizontal combination well pattern are preheated by using a throughput preheating method.

[0042] In some preferred embodiments, the throughput preheating rounds are 2-5 rounds.

[0043] In some preferred embodiments, before preheating the horizontal wells and vertical wells in the vertical-horizontal combination well pattern, the method further comprises:

[0044] Establishing a three-dimensional geological model for the deep ultra-heavy oil;

[0045] Calculating the well spacing between horizontal wells and each of the vertical wells, and between vertical wells in the vertical-horizontal combined well pattern according to the plane grid division of the three-dimensional geological model;

[0046] Calculating the horizontal wells in the vertical-horizontal combination well pattern and the formations where the vertical wells are located according to the vertical grid division of the three-dimensional geological model;

[0047] According to the calculation results, a straight and horizontal combined well pattern is set in the deep ultra-heavy oil reservoir.

[0048] In some preferred embodiments, the straight-horizontal combination well pattern further includes auxiliary drainage wells, which are connected to the horizontal wells to assist in oil production and drainage of the horizontal wells.

[0049] In a second aspect, the embodiments of this specification provide a SAGD injection and production method for a deep ultra-heavy oil reservoir, including:

[0050] A processing module, used for preheating horizontal wells and vertical wells in a straight-horizontal combination well pattern, wherein the straight-horizontal combination well pattern comprises a horizontal well and a plurality of vertical wells, wherein the plurality of vertical wells are symmetrically distributed on both sides of the horizontal well;

[0051] A judging module, used for judging whether the preheating process is completed;

[0052] The injection and production module is used for rotatingly injecting steam into at least part of the plurality of vertical wells when the preheating treatment is completed, and utilizing the horizontal wells to switch to SAGD oil production.

[0053] In some preferred embodiments, the device further comprises:

[0054] Establish a module for building a three-dimensional geological model of deep ultra-heavy oil;

[0055] A first calculation module is used to calculate the well spacing between the horizontal wells and each of the vertical wells, and between the vertical wells in the vertical-horizontal combination well pattern according to the plane grid division of the three-dimensional geological model;

[0056] A second calculation module is used to calculate the horizontal wells in the vertical and horizontal combined well pattern and the formations where the vertical wells are located according to the vertical grid division of the three-dimensional geological model;

[0057] The setting module is used to set a straight and horizontal combination well pattern in the deep super heavy oil reservoir according to the calculation results.

[0058] In a third aspect, an embodiment of the present specification also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method provided by the above technical solution when executing the computer program.

[0059] In a fourth aspect, an embodiment of the present specification further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method provided by the above technical solution is implemented.

[0060] In a fifth aspect, the embodiments of this specification also provide a computer program product, comprising at least one instruction or at least one program, wherein the at least one instruction or the at least one program is loaded and executed by a processor to implement the method provided by the above technical solution.

[0061] By adopting the above technical scheme, a SAGD injection and production method, device and computer equipment for deep ultra-heavy oil reservoirs provided in the embodiments of this specification are provided. By symmetrically arranging multiple vertical wells on both sides of the horizontal well to form a vertical and horizontal combined well network, and after the preheating of the horizontal wells and the vertical wells is completed, steam is injected into at least part of the vertical wells by rotating steam injection, thereby compensating for the heat loss caused by the burial depth during the exploitation of deep ultra-heavy oil reservoirs; effectively controlling the steam cavity rising speed and overburden height of individual steam injection well points, preventing single-point breakthrough of steam, and improving the development of steam cavity; solving the technical problem that the existing SAGD exploitation technology is difficult to apply to deep ultra-heavy oil reservoirs, realizing the exploitation of deep ultra-heavy oil reservoirs and greatly ensuring the recovery rate of similar deep reservoirs.

[0062] In order to make the above and other purposes, features and advantages of the embodiments of this specification more obvious and easy to understand, the following specifically cites preferred embodiments and describes them in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0064] Figure 1 A schematic diagram of the steps of a SAGD injection and production method for a deep super heavy oil reservoir provided in an embodiment of this specification is shown;

[0065] Figure 2 A schematic diagram of the structure of a straight and horizontal combined well pattern in an embodiment of this specification is shown;

[0066] Figure 3 The simulated daily oil production curves of deep super heavy oil reservoirs using a rotating steam injection method and a continuous steam injection method are shown;

[0067] Figure 4 The figure shows the comparison of the degree of recovery and the cumulative oil-gas ratio of deep super-heavy oil reservoirs when the rotation steam injection method and the continuous steam injection method are simulated;

[0068] Figure 5 A schematic diagram showing the steps of adjusting injection parameters and production parameters in the embodiment of this specification is shown;

[0069] Figure 6 The schematic diagram of the change of the SAGD oil recovery degree and the cumulative oil-gas ratio of the production well under different simulated steam chamber operating pressures is shown;

[0070] Figure 7 The following is a diagram showing the daily oil production curve of the SAGD oil production of the production well under different simulated steam chamber operating pressures;

[0071] Figure 8 The schematic diagram of steam cavity development under different simulated steam cavity operating pressures is shown;

[0072] Fig. 9 The following is a diagram showing the daily oil production curve of the SAGD oil production of the production well under different steam injection dryness simulated;

[0073] Fig.10 The schematic diagram of the simulated SAGD oil recovery degree and cumulative oil-gas ratio change of the production well under different steam injection dryness is shown;

[0074] Fig.11 The simulated curves of the SAGD oil recovery and the cumulative oil-gas ratio of the production well under different steam injection dryness are shown;

[0075] Fig.12The figure shows the relationship between different steam injection rates, different steam injection temperatures and bottom hole steam dryness under the condition of the simulated steam chamber operating pressure of 6MPa;

[0076] Fig.13 The oil-gas ratio and cumulative oil production curve of the SAGD production well under different simulated production-injection ratios are shown;

[0077] Fig.14 The schematic diagram of the stage recovery degree and cumulative oil-gas ratio change of horizontal well SAGD oil production under different simulated rotation steam injection cycles is shown;

[0078] Fig.15 A schematic diagram showing the steps of determining whether the preheating treatment is completed in the embodiment of this specification is shown;

[0079] Fig.16 A schematic diagram showing another step of determining whether the preheating treatment is completed in an embodiment of this specification;

[0080] Fig.17 A curve diagram showing the relationship between the simulated conversion drive recovery degree and the average daily oil production is shown;

[0081] Fig.18 A curve diagram showing the relationship between the simulated conversion drive recovery degree and the oil-gas ratio is shown;

[0082] Fig.19 The comparison diagram of recovery factor and oil-gas ratio at different simulated flooding times is shown;

[0083] Fig. 20 A schematic diagram showing the steps of setting a straight-horizontal combination well pattern in a deep ultra-heavy oil reservoir in an embodiment of this specification is shown;

[0084] Fig.21 A schematic diagram of the structure of a SAGD injection-production device for a deep super-heavy oil reservoir provided in an embodiment of this specification is shown;

[0085] Fig. 22 A schematic diagram of the structure of a computer device provided in an embodiment of this specification is shown.

[0086] Description of the accompanying symbols:

[0087] 10. Horizontal wells;

[0088] 20. Vertical well;

[0089] 21. The first straight well;

[0090] 22. Second vertical well;

[0091] 2110, processing module;

[0092] 2120, judgment module;

[0093] 2130, injection and production module;

[0094] 2202. Computer equipment;

[0095] 2204, processor;

[0096] 2206, memory;

[0097] 2208, driving mechanism;

[0098] 2210, input / output module;

[0099] 2212, input device;

[0100] 2214, output device;

[0101] 2216. Presentation equipment;

[0102] 2218. Graphical user interface;

[0103] 2220, network interface;

[0104] 2222, communication link;

[0105] 2224. Communication bus. DETAILED DESCRIPTION

[0106] The following will be combined with the drawings in the embodiments of this specification to clearly and completely describe the technical solutions in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this specification.

[0107] It should be noted that the terms "first", "second", etc. in this specification and claims 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 data used in this way can be interchanged where appropriate, so that the embodiments of this specification described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, device, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0108] The existing SAGD reservoir development injection and production methods are difficult to apply to deep ultra-heavy oil reservoirs. The steam chamber of deep ultra-heavy oil reservoirs is difficult to fully expand and stably drain oil, and cannot meet the requirements of high-dryness injection and large-displacement lifting. In order to solve the above problems, the embodiments of this specification provide a SAGD injection and production method and device for deep ultra-heavy oil reservoirs. Figure 1 This is a schematic diagram of the steps of a deep super-heavy oil reservoir SAGD injection and production method provided in the embodiment of this specification. This specification provides the method operation steps described in the embodiment or flow chart, but based on conventional or non-creative labor, more or fewer operation steps may be included. The order of steps listed in the embodiment is only one way of executing the order of many steps and does not represent the only execution order. When the system or device product is executed in practice, it can be executed in the order of the method shown in the embodiment or the figure or in parallel.

[0109] It should be noted that the SAGD injection and production method for deep ultra-heavy oil reservoirs provided in the embodiments of this specification is applicable to ultra-heavy oil and super-heavy oil, wherein the ultra-heavy oil refers to a reservoir with a viscosity greater than 10000 mPa.s, and the super-heavy oil refers to a reservoir with a viscosity greater than 50000 mPa.s; the deep layer refers to the burial depth of the reservoir within the range of 1000 to 1500 meters underground.

[0110] Specific as Figure 1 As shown, the method may include:

[0111] S110: preheating the horizontal wells and the vertical wells in the straight-horizontal combination well pattern, wherein the straight-horizontal combination well pattern comprises a horizontal well and a plurality of vertical wells, and the plurality of vertical wells are symmetrically distributed on both sides of the horizontal well.

[0112] like Figure 2 The figure is a schematic diagram of the structure of the straight and horizontal combination well network described in the embodiment of this specification.

[0113] It should be noted that, due to the influence of factors such as topography, the multiple vertical wells are symmetrically distributed on both sides of the horizontal well, which means that the number of vertical wells on both sides of the horizontal well is equal or the difference in the number of vertical wells on both sides is within a preset number difference range; and a pair of vertical wells symmetrically arranged on both sides of the horizontal well are at an equal distance from the horizontal well or the difference in distance is within a preset distance difference range, which is not necessarily completely symmetrical.

[0114] In the embodiments of this specification, the horizontal wells and each vertical well in the vertical-horizontal combination well network are preheated by injecting steam through injection pipes pre-installed in the horizontal wells and each vertical well, and the opening (including the opening degree) and closing of the injection pipes are computer controlled.

[0115] S120: Determine whether the preheating process is completed.

[0116] S130: When the preheating treatment is completed, steam is injected into at least part of the plurality of vertical wells in rotation, and the horizontal wells are used to switch to SAGD oil production.

[0117] In the embodiment of this specification, after preheating is completed, the horizontal well is used as a production well and the vertical well is used as an injection well; and when the vertical well is used to inject steam, a rotation steam injection method is adopted, that is, steam is first injected into at least part of the vertical well for a preset time, and then steam is injected into at least the remaining part of the vertical well for a preset time; and this is repeated until the horizontal well oil production is completed. Therefore, during the horizontal well production process, there is always a vertical well as an injection well for steam injection; but for the same vertical well, steam is injected intermittently during the horizontal well production process.

[0118] If continuous steam injection is adopted for all vertical wells during the horizontal well production process, the expansion morphology of the steam chambers at different steam injection well points is quite different due to the reservoir heterogeneity and the influence of continuous steam injection at the steam injection well points. The longitudinal expansion speed of the steam chamber formed gradually accelerates and exceeds its lateral expansion speed, and the lateral expansion mainly occurs in the upper part of the steam chamber, while the lateral expansion speed of the lower part of the steam chamber is very low; the steam chamber rising speed of individual steam injection well points is fast and the overburden height is high, which is prone to single-point steam breakthrough. The embodiment of this specification adopts the method of rotating steam injection, so that the steam chambers formed by the vertical well currently being injected with steam and the two adjacent wells that are not being injected with steam will gradually connect in the horizontal direction and expand into a larger steam chamber, which is conducive to the expansion and development of the steam chamber; with the expansion of the steam chamber, it is conducive to the enhancement of the oil well's oil drainage capacity, and the displacement of crude oil will gradually shift from steam displacement to steam-assisted gravity drainage, which is conducive to SAGD oil production operations.

[0119] The embodiments of the present specification provide a SAGD injection and production method for deep ultra-heavy oil reservoirs. The method comprises the following steps: symmetrically arranging a plurality of vertical wells on both sides of a horizontal well to form a vertical and horizontal combination well pattern; and after preheating the horizontal wells and the vertical wells, performing steam injection into at least part of the vertical wells in a rotating steam injection manner. This method compensates for the heat loss caused by the burial depth during the exploitation of deep ultra-heavy oil reservoirs; effectively controls the steam cavity rising speed and overburden height of individual steam injection well points, prevents single-point breakthrough of steam, and improves the development of the steam cavity. This method solves the technical difficulty that the existing SAGD exploitation technology is difficult to apply to deep ultra-heavy oil reservoirs, realizes the exploitation of deep ultra-heavy oil reservoirs, and greatly guarantees the recovery rate of similar deep reservoirs.

[0120] Furthermore, if Figure 2As shown, the multiple vertical wells 20 include at least two first vertical wells 21 and at least two second vertical wells 22. The first vertical wells 21 and the second vertical wells 22 located on the same side of the horizontal well 10 are alternately arranged, and a pair of vertical wells 20 symmetrically separated on both sides of the horizontal well 10 are the first vertical wells 21 and the second vertical wells 22 respectively.

[0121] That is Figure 2 As shown, the second vertical well 22 is adjacent to any one of the first vertical wells 21 and is arranged relative to the first vertical well 21 and the horizontal well 10; similarly, the first vertical well 21 is adjacent to and relative to any one of the second vertical wells 22.

[0122] Then, in step S130, alternately injecting steam into at least part of the plurality of vertical wells may further be:

[0123] Steam is injected into all the first vertical wells or all the second vertical wells in rotation for a preset time respectively until the oil production of the horizontal well is completed or a preset rotation round is reached.

[0124] That is, in one rotation process, only one of any two adjacent vertical wells is in a steam injection state; and only one of a pair of vertical wells symmetrically separated on both sides of the horizontal well is in a steam injection state.

[0125] like Figure 3 As shown, it is a simulated daily oil production curve of the deep super heavy oil reservoir exploited by the rotating steam injection method provided in the embodiment of this specification and the existing continuous steam injection method. Figure 3 Point A is the end point of stable production of deep ultra-heavy oil reservoirs when continuous steam injection is used, and point B is the end point of stable production of deep ultra-heavy oil reservoirs when rotation steam injection is used. The end point of stable production refers to the time point when the steam chamber starts to slowly develop downward from the boundaries on both sides of the top of the oil layer. Figure 3 It can be seen that during the SAGD injection and production process, when the vertical well adopts the rotation steam injection method, the daily oil production of the horizontal well is higher than that of the horizontal well when the vertical well adopts the continuous steam injection method. And when the vertical well adopts the rotation steam injection method, the stable production end point time of the horizontal well is later than that of the horizontal well when the vertical well adopts the continuous steam injection method, which means that when the vertical well adopts the rotation steam injection method, the horizontal well has a longer stable production time and higher production efficiency.

[0126] Figure 4 The following is a comparison of the recovery degree and cumulative oil-gas ratio of deep ultra-heavy oil reservoirs when using the rotation steam injection method and the continuous steam injection method. Figure 4 It can be seen that when the vertical well adopts the rotation steam injection method, the recovery degree and cumulative oil-gas ratio of the horizontal well are higher than those of the horizontal well when the vertical well adopts the continuous steam injection method.

[0127] Therefore, adopting the vertical and horizontal combined well pattern provided in the embodiment of this specification and adopting the rotation steam injection method for each vertical well in the SAGD injection and production development stage is conducive to extending the stable production period of deep ultra-heavy oil reservoir exploitation in horizontal wells and improving the recovery rate.

[0128] Further, in the embodiment of this specification, step S130: after the preheating treatment is completed, injecting steam into at least part of the plurality of vertical wells in turn, and using the horizontal wells to switch to SAGD oil production, may include:

[0129] Adjusting injection parameters when rotating steam injection into at least part of the plurality of vertical wells, the injection parameters at least including steam quality, steam injection rate and steam injection period of the injected steam; and

[0130] The production parameters when the horizontal well is converted to SAGD oil production are adjusted, and the production parameters at least include the production-injection ratio and the operating pressure of the steam chamber formed between the horizontal well and the vertical well.

[0131] The production-injection ratio is the ratio between the oil production of the horizontal well and the steam volume injected into the vertical well; the operating pressure of the steam chamber refers to the pressure at which the formation is developed during the SAGD injection-production process. That is, the SAGD injection-production method for deep ultra-heavy oil reservoirs provided in the embodiments of this specification regulates the above injection and production parameters before or during the SAGD injection-production of the reservoir to improve the recovery rate of the reservoir.

[0132] It should be noted that in some other feasible embodiments, fewer or higher injection and production parameters may be adjusted, or other injection and production parameters may also be adjusted, for example, the steam temperature, superheat and steam injection pressure during steam injection may also be included.

[0133] Specifically, Figure 5 As shown, adjusting the injection parameters when rotating the steam injection into at least part of the plurality of vertical wells, and adjusting the production parameters when using the horizontal wells to switch to SAGD oil production, further includes:

[0134] S510: Conduct sensitivity analysis on each injection parameter and each production parameter.

[0135] Sensitivity analysis can be used to indicate the degree of influence of input variables on output variables. The degree of influence is called the sensitivity coefficient of the input variable. The sensitivity coefficient is used to characterize the importance of the input variable under study to the output variable. The larger the sensitivity coefficient, the greater the influence of the input variable on the output variable, and vice versa.

[0136] In the embodiments of this specification, the input variables are the steam quality, steam injection rate and steam injection period of the above-mentioned injected steam, as well as the production-injection ratio and the operating pressure of the steam chamber; the output variable can be set to one or more of the daily oil production and cumulative oil-steam ratio of the deep ultra-heavy oil reservoir.

[0137] The sensitivity analysis can be established based on the response surface analysis method in the design of experiment (Design of Experiment, DOE). The design of experiment is a method for scientifically formulating experimental plans, rationally planning the types and times of experiments to comprehensively analyze data, which can shorten the experimental cycle, reduce the cost of the experiment, and obtain satisfactory results. There are many methods of DOE: full factorial design, orthogonal experimental design, uniform design, response surface analysis method (RSM), artificial neural network (ANN) and genetic algorithm (GA), etc. In the embodiments of this specification, the sensitivity analysis method adopted is not specifically limited.

[0138] S520: Determine the order of adjustment between the injection parameters and the production parameters according to the sensitivity analysis results.

[0139] That is, the sensitivity coefficients of the above-mentioned input variables relative to the output variables are calculated, and the order of adjustment between the injection parameters and the production parameters is determined according to the size of the sensitivity coefficients: the larger the sensitivity coefficient, the higher the order, and vice versa.

[0140] S530: Adjusting each injection parameter and each production parameter according to the sequence.

[0141] In the examples of this specification, the deep super-heavy oil reservoir has a burial depth of 1400 to 1690 m, an average oil layer thickness of 160 m, a porosity of 18.1%, and a permeability of 1381×10 -3 μm 2 , the cumulative oil production is 354,000 tons, and the cumulative water production is 877,000 tons. The sensitivity analysis of each injection parameter and each production parameter of this deep ultra-heavy oil reservoir is carried out, and the sensitivity coefficient relationship of each parameter is obtained as follows:

[0142] Operating pressure of steam chamber > steam dryness > steam injection rate > production-injection ratio > steam injection cycle.

[0143] In the embodiment of this specification, step S520: determining the order of adjustment between each injection parameter and each production parameter according to the sensitivity analysis result may be:

[0144] The injection parameters and production parameters are adjusted in descending order according to the sensitivity coefficient results obtained from the sensitivity analysis.

[0145] It should be noted that the above sensitivity analysis results correspond to the above deep ultra-heavy oil reservoir targeted by the embodiments of this specification. For other reservoirs, their sensitivity analysis results may be different from the above sensitivity analysis results.

[0146] The steam chamber operating pressure is adjusted according to the above sensitivity analysis results. Figure 6 The schematic diagram of the change of the SAGD oil recovery degree and the cumulative oil-gas ratio of the production well under different simulated steam chamber operating pressures is shown in Figure 2. Figure 6 As shown, with the increase of the operating pressure of the steam chamber, the recovery rate gradually decreases and the cumulative oil-gas ratio gradually increases. However, when the operating pressure of the steam chamber increases to above 4.0 MPa, the reduction in recovery rate slows down and the cumulative oil-gas ratio decreases.

[0147] Figure 7 The following is a daily oil production curve of SAGD oil production of production wells under different simulated steam chamber operating pressures. Figure 7 As shown, as the steam chamber operating pressure increases, the SAGD peak daily oil production decreases.

[0148] Figure 8 The following is a schematic diagram of the steam cavity development under different simulated steam cavity operating pressures. Figure 8 As shown, with the increase of operating pressure, the rising speed of the steam cavity is accelerated, the heat loss to the top cover layer increases, the lateral expansion of the steam cavity becomes worse, and the swept volume becomes smaller.

[0149] The operating pressure of the steam chamber affects the heat carried by the steam. The higher the operating pressure, the lower the latent heat of vaporization. If the operating pressure is low, it is difficult to ensure the liquid production. Figures 6 to 8 According to the simulation results, in the SAGD injection and production stage, the steam chamber operating pressure of the deep ultra-heavy oil reservoir described in the embodiments of this specification is appropriately regulated within the range of 4.5-6MPa to achieve better liquid supply capacity and higher oil-gas ratio.

[0150] Furthermore, the steam dryness is adjusted. Fig. 9 The following is a simulated daily oil production curve of SAGD oil production in production wells under different steam injection dryness. Fig.10 The figure is a schematic diagram of the simulated SAGD oil recovery and cumulative oil-gas ratio changes of production wells under different steam injection dryness. Fig. 9 and Fig.10 As shown in the figure, with the increase of steam dryness, the daily oil production peak increases, the production time of SAGD injection and production stage is shortened, and the oil production rate is increased; the latent heat of vaporization increases, the swept volume increases, and the cumulative oil-steam ratio shows an increasing trend. However, when the steam dryness is greater than 65%, the sensitivity of SAGD cumulative oil production to steam dryness decreases; after the dryness exceeds 60%, the degree of production remains basically stable. Therefore, in the embodiment of this specification, the bottom hole steam dryness is adjusted to be greater than 65%.

[0151] Furthermore, the steam injection rate is adjusted. Fig.11 The following is a curve of the simulated SAGD oil recovery and cumulative oil-gas ratio change of production wells under different steam injection dryness. Fig.11 As shown in the figure, with the increase of steam injection rate, the stage recovery degree and the cumulative oil-steam ratio slightly decrease; when the steam injection rate exceeds 120t / d, the stage recovery degree and the oil-steam ratio remain stable.

[0152] Fig.12 The figure is a schematic diagram of the relationship between different steam injection rates, different steam injection temperatures and bottom hole steam dryness under a certain steam chamber operating pressure (6MPa). Fig.12 It can be seen that when the operating pressure of the steam chamber is constant, at the same steam injection temperature, the bottom hole steam dryness increases with the increase of steam injection rate; at the same steam injection rate, the bottom hole steam dryness increases with the increase of steam injection temperature.

[0153] Thus, comprehensive Fig.11 and Fig.12 In the embodiments of this specification, the steam injection rate for rotating steam injection in vertical wells is adjusted within the range of 120-140t / d.

[0154] Fig.13 The following is a curve of the oil-gas ratio and cumulative oil production of the SAGD production well under different simulated production-injection ratios. Fig.13 As shown in the figure, when the production-injection ratio is less than 1.2, the bottom hole pressure increases, affecting the expansion of the steam cavity, causing the oil drainage rate to decrease and the production effect to deteriorate; when the production-injection ratio exceeds 1.2, the steam cavity expansion rate does not change much, and the cumulative oil production and oil-gas ratio no longer increase. In the embodiment of this specification, the production-injection ratio of deep ultra-heavy oil is finally adjusted to be greater than or equal to 1.2.

[0155] It should be noted that in the embodiments of this specification, the vertical and horizontal combination well pattern includes multiple vertical wells. When performing SAGD injection and production, there are multiple vertical wells in a steam injection state, and the total amount of steam injected into the vertical wells is relatively large. Therefore, in order to ensure that the injection-production ratio between the oil production of the horizontal wells and the amount of steam injected into the vertical wells satisfies the condition of being greater than or equal to 1.2, the vertical and horizontal combination well pattern may also be provided with an auxiliary drainage well (not shown in the figure), which is connected to the horizontal wells and is used to assist the horizontal wells in oil production and drainage.

[0156] Furthermore, the steam injection cycle is adjusted. Fig.14 The figure is a schematic diagram of the stage recovery degree and cumulative oil-gas ratio changes of horizontal well SAGD oil production under different rotation steam injection cycles. Fig.14As shown in the figure, as the rotation steam injection cycle increases, the stage production degree decreases, while the cumulative oil-gas ratio remains stable. Therefore, in the embodiment of this specification, the rotation steam injection cycle of the vertical well is adjusted to 2-3 months. That is, after suspending steam injection to all second vertical wells and injecting steam to all first vertical wells for 2-3 months, suspending steam injection to all first vertical wells and injecting steam to all second vertical wells for 2-3 months, and repeating this process until the horizontal well oil production ends.

[0157] In summary, the optimized and adjusted injection and sampling parameters in the embodiments of this specification are shown in the following table:

[0158] Injection and Production Parameters Table

[0159] parameter Optimized value Steam chamber operating pressure 4.5-6MPa Steam dryness ≥65％ Steam injection rate 120-140t / d Production-injection ratio ≥1.2 Steam injection cycle February-March

[0160] By adjusting the injection parameters and production parameters during the conversion to SAGD injection and production, the deep ultra-heavy oil reservoirs can be utilized to the greatest extent, which is beneficial to improving the production and development efficiency of the deep ultra-heavy oil reservoirs.

[0161] After the preheating of the horizontal wells and each vertical well in the vertical-horizontal combination well pattern is completed, the SAGD injection and production can be switched. Therefore, judging whether the preheating treatment is completed is the key to switching to SAGD injection and production. Fig.15 As shown, in the embodiment of this specification, step S120: judging whether the preheating treatment is completed may include the following steps:

[0162] S1510: Obtain the inter-well temperature and inter-well formation pressure between the horizontal well and the vertical well.

[0163] The inter-well temperature can be monitored by using a plurality of thermocouples pre-set at the horizontal well and the vertical well, and the formation pressure can be monitored by using a pre-set pressure monitoring element.

[0164] S1520: Determine whether the inter-well temperature reaches a preset temperature and whether the inter-well formation pressure reaches a preset pressure.

[0165] Exemplarily, the preset temperature may be set to 80° C., and the preset pressure may be set to 4 MPa.

[0166] S1530: If yes, the preheating process is completed.

[0167] That is, when the interwell temperature reaches 80°C or above and the interwell formation pressure is less than 4MPa or below, it is judged that the preheating of the horizontal well and the vertical well is completed and can be switched to SAGD development.

[0168] like Fig.16 As shown, in some preferred embodiments, step S120: determining whether the preheating treatment is completed may include the following steps:

[0169] S1610: Acquire the degree of recovery of the deep extra heavy oil reservoir after the horizontal well and the vertical well complete the current round of throughput preheating during the preheating process.

[0170] In the embodiment of this specification, the horizontal wells and vertical wells in the vertical-horizontal combination well network are preheated by using a throughput preheating method, that is, steam is injected into the horizontal wells and all vertical wells at the same time and for a preheating cycle. The injected steam exchanges heat with the crude oil in the oil layer, and the crude oil is heated and viscosity-reduced, and the condensed water of the steam flows down to the horizontal wells under the action of gravity for production. One injection and one production completed within the preset cycle is a throughput preheating round. When the water content in the produced oil-water mixture is higher than the preset water content threshold, it is determined that the next round of throughput preheating can be carried out.

[0171] S1620: Determine whether the recovery degree is greater than a preset recovery degree threshold.

[0172] The recovery degree can be calculated by the oil content in the oil-water mixture produced after the current round of throughput preheating is completed and the initial oil storage capacity of the deep extra-heavy oil reservoir.

[0173] Fig.17 The relationship curve between the simulated conversion recovery degree and the average daily oil production is shown in Figure 2. Fig.18 The relationship between the simulated conversion recovery degree and the oil-gas ratio is shown in Figure 2. Fig.17 and 18 As shown, as the recovery degree increases when switching to SAGD production, the average daily oil production and oil-gas ratio gradually decrease; that is, the later the timing of switching to SAGD injection and production, the lower the recovery rate of the SAGD injection and production stage. Exemplarily, in this specification, the recovery degree threshold is set to 30% to ensure that the conversion to SAGD injection and production can have a higher recovery rate.

[0174] However, if the timing of switching to SAGD injection and production is too early, the preheating of horizontal wells and vertical wells has not been completed, which will also have an adverse effect on the recovery rate of the SAGD injection and production stage. Therefore, it is necessary to judge the preheating results while ensuring the recovery rate.

[0175] S1630: If yes, then obtain the inter-well temperature and inter-well formation pressure between the horizontal well and the vertical well.

[0176] S1640: Determine whether the inter-well temperature reaches a preset temperature and whether the inter-well formation pressure reaches a preset pressure.

[0177] S1650: If yes, the preheating process is completed.

[0178] Monitoring and judgment methods of interwell temperature and interwell formation pressure Fig.15The method shown is the same and will not be described again here. Switch to SAGD production, perform rotation steam injection on vertical wells, and produce oil on horizontal wells.

[0179] Fig.19 The comparison chart of recovery factor and oil-gas ratio at different simulated flooding times is shown in Figure 2. Fig.19 As shown in the figure, with the increase of the preheating rounds of the horizontal well and the vertical well, the recovery factor and the oil-gas ratio both increase first and then decrease, and both have a peak value when the preheating round is 2; while the stage recovery degree gradually decreases with the increase of the preheating rounds. Figures 17 to 19 According to the simulation results, in the embodiments of this specification, the preheating treatment of horizontal wells and vertical wells is carried out for 2-5 rounds of throughput preheating, and SAGD is switched when the oil reservoir recovery rate is about 30%, which can achieve a double improvement in SAGD development effect and economic benefits.

[0180] S1660: If not, the horizontal well and the vertical well need to continue to be preheated.

[0181] If the inter-well temperature does not reach the preset temperature and the inter-well formation pressure does not reach the preset pressure, it is determined that the preheating treatment is not completed, and the horizontal well and the vertical well need to continue the preheating treatment.

[0182] The embodiments of this specification provide Fig.16 The method for judging whether the preheating treatment is completed is to first judge the degree of production, so that when the degree of production has not reached the threshold value of the degree of production, the preheating treatment has not been completed, so there is no need to judge the inter-well temperature and the inter-well formation pressure, which can simplify the supervision of the operator; and when the degree of production reaches the threshold value of the degree of production, the inter-well temperature and the inter-well formation pressure are used to judge, so as to ensure that the judgment on the completion of the preheating treatment has a high accuracy while ensuring the economy of switching to SAGD injection and production.

[0183] In some other embodiments, other methods may be combined to determine whether the preheating treatment of the horizontal wells and the vertical wells in the vertical-horizontal combination well pattern is completed.

[0184] For example, the underground temperature field distribution between the horizontal well and the vertical well can be obtained by using the oil well temperature measurement results and / or numerical simulation methods;

[0185] According to the temperature field distribution, determining whether the horizontal well and the vertical well are thermally connected;

[0186] If the horizontal well is thermally connected to the vertical well, the preheating treatment is completed.

[0187] For another example, the viscosity of crude oil after preheating treatment in deep ultra-heavy oil reservoirs can also be obtained;

[0188] Determining whether the viscosity of the crude oil is less than or equal to a preset viscosity threshold;

[0189] If so, it is determined that the preheating process is completed.

[0190] Combining the above judgment methods, the accuracy of judging whether the preheating treatment is completed can be improved, thereby improving the accuracy of the timing of switching to SAGD injection and production, which is beneficial to improving the development effect and economic benefits of the SAGD injection and production stage.

[0191] like Fig. 20 As shown, in the embodiment of this specification, before preheating the horizontal wells and vertical wells in the vertical-horizontal combination well pattern in step S110, the method may further include:

[0192] S2010: Establishing a three-dimensional geological model for the deep extra-heavy oil.

[0193] S2020: Calculate the well spacing between the horizontal wells and each of the vertical wells, and between the vertical wells in the vertical-horizontal combined well network according to the plane grid division of the three-dimensional geological model.

[0194] S2030: Calculate the horizontal wells in the vertical-horizontal combination well pattern and the formations where the vertical wells are located according to the vertical grid division of the three-dimensional geological model.

[0195] S2040: According to the calculation results, a straight-horizontal combination well pattern is set in the deep ultra-heavy oil reservoir.

[0196] By setting a straight and horizontal combination well pattern suitable for deep ultra-heavy oil reservoirs, SAGD injection and production of deep ultra-heavy oil reservoirs is facilitated.

[0197] like Fig.21 As shown, the embodiment of this specification also provides a SAGD injection and production device for a deep ultra-heavy oil reservoir, comprising:

[0198] Processing module 2110, for preheating horizontal wells and vertical wells in a straight-horizontal combination well pattern, wherein the straight-horizontal combination well pattern includes a horizontal well and a plurality of vertical wells, wherein the plurality of vertical wells are symmetrically distributed on both sides of the horizontal well;

[0199] A determination module 2120 is used to determine whether the preheating process is completed;

[0200] The injection and production module 2130 is used to rotate the steam injection into at least part of the multiple vertical wells when the preheating treatment is completed, and utilize the horizontal wells to switch to SAGD oil production.

[0201] Furthermore, the device also includes:

[0202] Establish a module for building a three-dimensional geological model of deep ultra-heavy oil;

[0203] A first calculation module is used to calculate the well spacing between the horizontal wells and each of the vertical wells, and between the vertical wells in the vertical-horizontal combination well pattern according to the plane grid division of the three-dimensional geological model;

[0204] A second calculation module is used to calculate the horizontal wells in the vertical and horizontal combined well pattern and the formations where the vertical wells are located according to the vertical grid division of the three-dimensional geological model;

[0205] The setting module is used to set a straight and horizontal combination well pattern in the deep super heavy oil reservoir according to the calculation results.

[0206] The beneficial effects obtained by the device provided in the embodiments of this specification are consistent with the beneficial effects obtained by the above method and will not be repeated here.

[0207] like Fig. 22 As shown, a computer device provided in an embodiment of this specification is provided. A deep super heavy oil reservoir SAGD injection and production device in this specification can be a computer device in this embodiment, and the above method of this specification is executed. The computer device 2202 may include one or more processors 2204, such as one or more central processing units (CPUs), and each processing unit may implement one or more hardware threads. The computer device 2202 may also include any memory 2206, which is used to store any kind of information such as code, settings, data, etc. Non-limiting, for example, the memory 2206 may include any one or more combinations of the following: any type of RAM, any type of ROM, flash memory device, hard disk, optical disk, etc. More generally, any memory can use any technology to store information. Further, any memory can provide volatile or non-volatile retention of information. Further, any memory can represent a fixed or removable component of the computer device 2202. In one case, when the processor 2204 executes an associated instruction stored in any memory or a combination of memories, the computer device 2202 can perform any operation of the associated instruction. The computer device 2202 also includes one or more drive mechanisms 2208 for interacting with any storage, such as a hard disk drive mechanism, an optical disk drive mechanism, etc.

[0208] The computer device 2202 may also include an input / output module 2210 (I / O) for receiving various inputs (via input device 2212) and for providing various outputs (via output device 2214). A specific output mechanism may include a presentation device 2216 and an associated graphical user interface (GUI) 2218. In other embodiments, the input / output module 2210 (I / O), input device 2212, and output device 2214 may not be included, and the computer device 2202 may be used as a computer device in a network. The computer device 2202 may also include one or more network interfaces 2220 for exchanging data with other devices via one or more communication links 2222. One or more communication buses 2224 couple the components described above together.

[0209] The communication link 2222 may be implemented in any manner, for example, through a local area network, a wide area network (e.g., the Internet), a point-to-point connection, etc., or any combination thereof. The communication link 2222 may include any combination of hardwired links, wireless links, routers, gateway functions, name servers, etc. governed by any protocol or combination of protocols.

[0210] Corresponding to Figure 1 , Figure 5 , Figure 15 to Figure 16 and Fig. 20 In addition to the method shown, an embodiment of the specification also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above method are executed.

[0211] The embodiment of the present specification also provides a computer-readable instruction, wherein when the processor executes the instruction, the program therein causes the processor to execute the following Figure 1 , Figure 5 , Figure 15 to Figure 16 and Fig. 20 The method shown.

[0212] The embodiments of the present specification also provide a computer program product, including at least one instruction or at least one program, wherein the at least one instruction or the at least one program is loaded and executed by a processor to implement the following Figure 1 , Figure 5 , Figure 15 to Figure 16 and Fig. 20 The method shown.

[0213] It should be understood that in the various embodiments of this specification, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this specification.

[0214] It should also be understood that in the embodiments of this specification, the term "and / or" is only a description of the association relationship of the associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this specification generally indicates that the associated objects before and after are in an "or" relationship.

[0215] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in this specification can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this specification.

[0216] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0217] In the several embodiments provided in this specification, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or it can be an electrical, mechanical or other form of connection.

[0218] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of this specification.

[0219] In addition, each functional unit in each embodiment of this specification may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0220] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this specification is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of this specification. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0221] Specific embodiments are used in this specification to illustrate the principles and implementation methods of this specification. The description of the above embodiments is only used to help understand the methods and core ideas of this specification. At the same time, for those skilled in the art, according to the ideas of this specification, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on this specification.

Claims

1. A SAGD injection and production method for deep ultra-heavy oil reservoirs, characterized in that: include: Preheating the horizontal wells and vertical wells in a straight-horizontal combination well pattern, wherein the straight-horizontal combination well pattern includes a horizontal well and a plurality of vertical wells, wherein the plurality of vertical wells are symmetrically distributed on both sides of the horizontal well; Determining whether the preheating treatment is completed; When the preheating treatment is completed, steam is injected into at least part of the plurality of vertical wells in rotation, and the horizontal wells are used to switch to SAGD oil production.

2. The method according to claim 1, characterized in that The plurality of vertical wells include at least two first vertical wells and at least two second vertical wells, the first vertical wells and the second vertical wells located on the same side of the horizontal well are alternately arranged, and a pair of vertical wells symmetrically separated on both sides of the horizontal well are the first vertical well and the second vertical well respectively; The step of rotating the steam injection into at least a portion of the plurality of vertical wells further comprises: Steam is injected into all the first vertical wells or all the second vertical wells in rotation for a preset time respectively until the oil production of the horizontal well is completed or a preset rotation round is reached.

3. The method according to claim 1, characterized in that: After the preheating treatment is completed, steam is injected into at least part of the plurality of vertical wells in turn, and the horizontal wells are used for SAGD oil production, further comprising: adjusting injection parameters when rotating steam injection into at least a portion of the plurality of vertical wells; and The production parameters when converting the horizontal well to SAGD oil production are adjusted.

4. The method according to claim 3, characterized in that The injection parameters at least include the steam quality, injection speed and injection period of the injected steam, and the production parameters at least include the production-injection ratio and the operating pressure of the steam chamber formed between the horizontal well and the vertical well.

5. The method according to claim 3, characterized in that: Adjusting the injection parameters when rotating the steam injection into at least part of the plurality of vertical wells, and adjusting the production parameters when switching to SAGD oil production using the horizontal wells, further comprises: Conduct sensitivity analysis on various injection parameters and production parameters; According to the results of sensitivity analysis, determine the order of adjustment between various injection parameters and various production parameters; The injection parameters and production parameters are adjusted according to the sequence.

6. The method according to claim 5, characterized in that According to the sensitivity analysis results, the order of adjustment between the injection parameters and the production parameters is determined, further including: The injection parameters and production parameters are adjusted in descending order according to the sensitivity coefficient results obtained from the sensitivity analysis.

7. The method according to claim 4, characterized in that The steam dryness is adjusted to be greater than 65%, the steam injection rate is adjusted to 120-140 t / d, the production-injection ratio is adjusted to 1.2, the operating pressure is adjusted to 4.5-6 MPa, and the steam injection cycle is adjusted to 2-3 months.

8. The method according to claim 1, characterized in that: Determining whether the preheating treatment is completed further includes: Acquiring the interwell temperature and interwell formation pressure between the horizontal well and the vertical well; Determining whether the inter-well temperature has reached a preset temperature and whether the inter-well formation pressure has reached a preset pressure; If yes, the preheating process is complete.

9. The method according to any one of claims 1 or 8, characterized in that: Determining whether the preheating treatment is completed further includes: Obtaining the underground temperature field distribution between the horizontal well and the vertical well through oil well temperature measurement results and / or numerical simulation methods; According to the temperature field distribution, determining whether the horizontal well and the vertical well are thermally connected; If yes, the preheating process is complete.

10. The method according to claim 9, characterized in that Determining whether the preheating treatment is completed further includes: Obtaining the crude oil viscosity of the deep ultra-heavy oil reservoir; Determining whether the viscosity of the crude oil is less than or equal to a preset viscosity threshold; If yes, the preheating process is complete.

11. The method according to claim 1, characterized in that: Determining whether the preheating treatment is completed includes: Acquire the recovery degree of the deep super-heavy oil reservoir after the horizontal well and the vertical well complete the current round of preheating during the preheating process; Determining whether the recovery degree is greater than a preset recovery degree threshold; If yes, then obtaining the interwell temperature and interwell formation pressure between the horizontal well and the vertical well; Determining whether the inter-well temperature has reached a preset temperature and whether the inter-well formation pressure has reached a preset pressure; If yes, the preheating treatment is completed; If not, the horizontal well and the vertical well continue to be preheated.

12. The method according to claim 11, characterized in that The horizontal wells and vertical wells in the vertical-horizontal combination well pattern are preheated by using the huff-and-puff preheating method.

13. The method according to claim 12, characterized in that The number of rounds of throughput preheating is 2-5 rounds.

14. The method according to claim 1, characterized in that Before preheating the horizontal wells and vertical wells in the vertical-horizontal combination well pattern, the method further comprises: Establishing a three-dimensional geological model for the deep ultra-heavy oil; Calculating the well spacing between horizontal wells and each of the vertical wells, and between vertical wells in the vertical-horizontal combined well pattern according to the plane grid division of the three-dimensional geological model; Calculating the horizontal wells in the vertical-horizontal combination well pattern and the formations where the vertical wells are located according to the vertical grid division of the three-dimensional geological model; According to the calculation results, a straight and horizontal combined well pattern is set in the deep ultra-heavy oil reservoir.

15. The method according to claim 14, characterized in that The straight-horizontal combination well pattern also includes auxiliary drainage wells, which are connected to the horizontal wells to assist in oil production and drainage of the horizontal wells.

16. A SAGD injection and production device for deep ultra-heavy oil reservoirs, characterized in that: include: A processing module, used for preheating horizontal wells and vertical wells in a straight-horizontal combination well pattern, wherein the straight-horizontal combination well pattern comprises a horizontal well and a plurality of vertical wells, wherein the plurality of vertical wells are symmetrically distributed on both sides of the horizontal well; A judging module, used for judging whether the preheating process is completed; The injection and production module is used for rotatingly injecting steam into at least part of the plurality of vertical wells when the preheating treatment is completed, and utilizing the horizontal wells to switch to SAGD oil production.

17. The device according to claim 16, characterized in that The device also includes: Establish a module for building a three-dimensional geological model of deep ultra-heavy oil; A first calculation module is used to calculate the well spacing between the horizontal wells and each of the vertical wells, and between the vertical wells in the vertical-horizontal combination well pattern according to the plane grid division of the three-dimensional geological model; A second calculation module is used to calculate the horizontal wells in the vertical and horizontal combined well pattern and the formations where the vertical wells are located according to the vertical grid division of the three-dimensional geological model; The setting module is used to set a straight and horizontal combination well pattern in the deep super heavy oil reservoir according to the calculation results.

18. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 15 is implemented.

19. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 15 is implemented.

20. A computer program product, characterized in that The method comprises at least one instruction or at least one program, wherein the at least one instruction or the at least one program is loaded and executed by a processor to implement the method according to any one of claims 1 to 15.

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