A method, system and application for promoting uniform distribution of heavy oil aquathermal cracking catalyst

Abstract

The present invention relates to the technical field of heavy oil production, specifically a method, system and application for promoting uniform distribution of heavy oil aquathermolysis catalyst, the application comprising the following steps: selecting an oil-soluble aquathermolysis catalyst and its injection layer according to reservoir formation conditions; injecting the oil-soluble aquathermolysis catalyst into the formation from a vertical well, injecting the first section of steam at the same position, placing a packer, and shutting in the well according to the needs of the oil-soluble aquathermolysis catalyst; sequentially injecting oil-based foam and the second section of steam into the perforated section along the perforated section below the packer, and removing the packer after the injection is completed; after the well is shut in for reaction, the well is opened for steam drive production until the production is completed; the placement position of the packer is the middle and lower part of the steam injection perforated section. Through the selection of the catalyst and its carrier and the regulation of the injection process, the uniform distribution of the aquathermolysis catalyst in the formation is achieved, which greatly improves the coupling efficiency of steam and catalyst.

Description

Technical Field

[0001] The invention relates to the technical field of heavy oil production, and in particular to a method, a system and an application of promoting uniform distribution of a heavy oil aquathermal cracking catalyst. Background Art

[0002] Heavy oil steam development is one of the main technologies for developing high-viscosity heavy oil reservoirs. Traditional methods such as steam stimulation, steam flooding and steam-assisted gravity drainage (SAGD) use steam injection to increase the temperature of the reservoir, reduce the viscosity of crude oil, and thus increase its fluidity. Steam stimulation has become a more commonly used technology in heavy oil development due to its simplicity and relatively low cost, especially in shallow heavy oil reservoirs. However, with the increase in steam injection cycles, the pressure of the reservoir gradually decreases, and the recovery factor will gradually decrease. Over time, the steam injection efficiency and oil production have decreased significantly, and it is necessary to increase the amount of steam or use chemical additives to maintain economic benefits. Unlike steam stimulation technology, steam flooding is to continuously inject steam into the reservoir to push the heavy oil to the production well through displacement; SAGD greatly improves oil recovery efficiency through injection and production coordination of horizontal wells. However, these methods rely on a large amount of energy consumption and water resources, and are accompanied by environmental problems and economic feasibility challenges.

[0003] In this context, the in-situ heavy oil modification technology came into being. By directly thermally cracking or chemically modifying heavy oil underground, high-viscosity heavy oil can be converted into light oil products, which can not only effectively improve the recovery rate, but also significantly reduce the amount of steam injection, energy consumption and environmental load. The promotion and application of in-situ heavy oil modification can not only make up for the shortcomings of traditional heavy oil steam development technology, but also provide new ideas for the green development of heavy oil and extra-heavy oil in the future. At present, the combination of catalytic aquathermolysis and steam thermal recovery is a hot technology for improving the quality and efficiency of heavy oil development. Steam can provide reaction temperature for the catalyst while heating the formation.

[0004] The key to improving the effect of catalytic aquathermolysis is to make the catalyst and crude oil come into effective contact. To achieve this effect, the prior art has proposed several improvement methods. For example, Chinese patent document CN 115992680 A (application number 202111225013.5) discloses an underground in-situ catalytic cracking and upgrading process for heavy oil for steam drive, which uses regenerated solid waste catalyst and ground-filled quartz sand to promote the contact and mixing of catalyst and heavy oil. Another example is the journal document "Research Progress of Aquathermolysis Technology for Heavy Oil Production", Xu Fang, Nan Yu, et al. Guangdong Chemistry, 2022, 49(18):81-82. It introduces the improvement directions in this field, including catalysts, hydrogen donors and viscosity reduction mechanisms. It can be seen that the prior art is still limited to the selection and improvement of injected materials when catalytic aquathermolysis is carried out, but the problem of uneven distribution of catalysts in the formation caused by the gravity separation of steam and catalyst has not been solved. Compared with steam with lower density, catalysts in the form of fluids / particles are mostly distributed in the oil-water solution at the bottom of the formation; at the same time, the catalyst injected into the formation is affected by the interface characteristics and wettability, and the distribution targeting and balance are poor. Based on this, improving and adjusting the distribution of heavy oil aquathermal cracking catalysts and improving the coupling efficiency of catalysts and steam are the challenges facing this field.

[0005] Therefore, there is an urgent need to provide a method for improving the distribution effect of aquathermolysis catalysts. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a method and system for promoting uniform distribution of heavy oil aquathermolysis catalyst. By selecting the catalyst and its carrier and regulating the injection process, the uniform distribution of the aquathermolysis catalyst in the formation is achieved, which greatly improves the coupling efficiency of steam and catalyst.

[0007] In order to achieve the above technical effects, the present invention adopts the following technical solutions:

[0008] A method for promoting uniform distribution of a heavy oil aquathermal cracking catalyst comprises the following steps:

[0009] S1. Selecting an oil-soluble water thermal cracking catalyst and its injection position according to reservoir formation conditions;

[0010] S2. After injecting an oil-soluble water thermal cracking catalyst into the formation from a vertical well, injecting the first stage of steam at the same location and placing a packer;

[0011] S3. injecting oil-based foam and second-stage steam into the perforation sections determined in step S2 below the packer, and removing the packer after the injection is completed;

[0012] S4. After the well is shut down for reaction, the well is opened for steam drive production until the production is completed;

[0013] In step S2, the packer is placed in the middle and lower part of the steam injection perforation section;

[0014] In step S2, if the oil-soluble water thermal cracking catalyst needs a certain amount of time to be converted into a state with catalytic activity in the formation, the well needs to be shut down for treatment after the placement of the packer. For example, hexadecyl trimethylammonium heptamolybdate has catalytic activity only after it is decomposed into molybdenum disulfide, and the time required for the decomposition process is the shut-in time. If the oil-soluble water thermal cracking catalyst itself already has catalytic activity, there is no need to shut down the well for treatment.

[0015] In the process of aquathermolysis catalyst injection, hot steam exists in gaseous form, which is very easy to float in the formation, flow along the cap rock at the top of the reservoir, and present a funnel-like distribution around the injection well. Catalysts mostly exist in the form of fluids or particles, and their density is greater than that of steam. Most of them cannot be transported by steam, so more catalysts are concentrated in the lower part of the reservoir. This is the gravity separation of catalysts and steam. The high-temperature area of ​​the reservoir is the steam-affected area, which causes the catalyst in the lower part of the formation to be unable to be heated to the catalytic temperature, resulting in poor modification effect on heavy oil.

[0016] In the method provided by the present invention, by using an oil-soluble water thermal cracking catalyst and an oil-based foam as a catalyst transport carrier, the contact efficiency between the catalyst and the crude oil is significantly enhanced, and the interference of solubility, interface factors, etc. on the catalyst acting on the heavy oil is reduced. After the steam injected in step S2 preliminarily establishes a temperature field in the formation and the catalyst is in a reactive state, the oil-based foam is injected from below the packer. By optimizing the injection position of the oil-based foam, the gravity differentiation phenomenon of the catalyst and the steam is significantly controlled. On the basis of the optimized catalyst distribution, steam is continuously injected to consolidate the temperature field to meet the catalyst reaction conditions.

[0017] Preferably, in step S1, the reservoir formation conditions include reservoir thickness, heavy oil reserves in the reservoir, and pore volume in the reservoir;

[0018] The oil-soluble hydrothermal cracking catalyst includes a modified transition metal oxide, a modified transition metal sulfide or a transition metal organic acid salt and a complex thereof having catalytic activity for heavy oil, the transition metal concentration in the oil-soluble hydrothermal cracking catalyst is 20 μg / g-250 μg / g, the catalyst solvent in the oil-soluble hydrothermal cracking catalyst is diesel or catalytic diesel; the catalytic temperature of the oil-soluble hydrothermal cracking catalyst is lower than 300°C.

[0019] Specifically, the oil-soluble water thermal cracking catalyst can be selected from hexadecyl trimethylammonium heptamolybdate, iron oleate, nickel oleate or nano black card.

[0020] Preferably, in step S2, the amount of oil-soluble water thermal cracking catalyst used is 0.3wt%-1.5wt% of the heavy oil reserves in the reservoir, the injection amount of the first stage steam is 0.1PV-0.3PV, the injection amount of the first stage steam is measured by liquid water volume, the injection rate of the first stage steam is 100t / d-150t / d, and the temperature of the second stage steam is 250℃-350℃; further preferably, the injection amount of the first stage steam is 0.2PV.

[0021] The injection volume of the first stage steam should not be too much. When it exceeds 0.3PV, that is, more than 0.3 times the pore volume in the reservoir, more heat will be generated due to factors such as gravity differentiation, resulting in the steam being unable to be effectively used to provide the temperature field conditions required for the catalyst; when it is less than 0.1PV, that is, less than 0.1 times the pore volume in the reservoir, part of the injected catalyst cannot be effectively converted into an active and reactive state, requiring an increase in the subsequent soaking time, delaying the construction progress.

[0022] Preferably, in step S2, the placement position of the packer is specifically from the vertical middle section of the steam injection perforation section to the bottom end of the perforation section, which accounts for 1 / 4 of the total vertical length of the perforation section. If the perforation section is 1120 meters to 1160 meters underground, the placement position of the packer is from 1140 meters underground (the vertical middle section of the perforation section) to 1150 meters (i.e., the position from the bottom end of the perforation section to 1 / 4 of the total vertical length of the perforation section); further preferably, the placement position of the packer is from the bottom end of the perforation section to 1 / 4 of the total vertical length of the perforation section.

[0023] If the injection position of the oil-based foam is the full perforation section or the upper perforation section corresponding to the reservoir thickness, the catalyst located in the lower part of the reservoir cannot be effectively transported and carried because the density of the oil-based foam is lower than that of the catalyst. By limiting the injection position of the oil-based foam, the uniformity of the catalyst distribution in the reservoir is significantly improved.

[0024] Preferably, in step S3, the injection volume of the oil-based foam is 0.05PV-0.15PV, the foaming volume of the oil-based foam is ≥150mL, the liquid separation half-life is ≥180s, and the mass of the oil-based foam is 60%-80%, that is, the volume of gas in the oil-based foam accounts for 60%-80% of the total volume of the oil-based foam;

[0025] Oil-based foams consist of gas, surfactants and solvents.

[0026] The gas is selected from N2, CO2, flue gas or other commonly used additive gases in oil fields.

[0027] The surfactant is a single component of a fluorinated surfactant or a silicon-containing surfactant, or a composite component of a fluorinated surfactant or a silicon-containing surfactant and a phosphate ester or Span20.

[0028] Solvent kerosene or diesel.

[0029] Further preferably, when the surfactant is a single component, the mass ratio of the surfactant to the oil-based foam is 0.3wt%-0.35wt%; when the surfactant is a compound component, the mass ratio of the surfactant to the oil-based foam is 1.5wt%-2.5wt%.

[0030] Preferably, in step S3, the injection amount of the second stage steam is 0.08PV-0.12PV, the injection amount of the second stage steam is measured by liquid water volume, the injection rate of the second stage steam is 100t / d-150t / d, the temperature of the second stage steam is 250℃-350℃, and the temperature of the second stage steam is higher than the catalytic temperature of the oil-soluble water thermal cracking catalyst injected in step S2.

[0031] Further preferably, in step S3, the injection rate of the second stage steam is 100 t / d and the temperature is 320°C.

[0032] Preferably, in step S4, the well is shut down for 2 to 5 days, and the shut-in time is determined according to the optimal reaction time required for the oil-soluble water thermal cracking catalyst injected in step S2. For example, if the optimal catalytic time of nano black card is 2 days, when nano black card is used as the oil-soluble water thermal cracking catalyst, the well can be shut down for 2 days.

[0033] Preferably, in step S4, the injection rate of steam flooding is 150 t / d and the temperature is 300° C.;

[0034] The condition for the end of production is that the water content in the output fluid is ≥98.5%.

[0035] The present invention also provides a system for implementing the above method for promoting uniform distribution of heavy oil aquathermal cracking catalyst, comprising an oil-based foam injection module, a catalyst injection module and a steam injection module.

[0036] The oil-injection-based foam module comprises a gas storage device, a surfactant storage device, a foam generator and a first pressurizing device, the gas storage device and the surfactant storage device are connected to the foam generator, a gas flow meter is provided between the gas storage device and the foam generator, and the foam generator is connected to the first pressurizing device;

[0037] The catalyst injection module includes a catalyst storage device and a second pressurizing device connected in sequence;

[0038] The steam injection device comprises a steam generator and a third pressurizing device connected in sequence;

[0039] The first booster device is used to inject oil-based foam into the formation, the second booster device is used to inject catalyst into the formation, and the third booster device is used to inject steam into the formation.

[0040] In the above system, the gas flow meter is used to control the foam quality during oil-based foam injection, so that the foam is injected into the formation in a more stable form and with higher strength, effectively carrying the decomposed catalytically active particles to enhance the catalytic aquathermal cracking effect of the catalyst, thereby effectively improving the recovery rate.

[0041] The present invention also provides the use of the method for promoting uniform distribution of heavy oil aquathermal cracking catalyst or the system for promoting uniform distribution of heavy oil aquathermal cracking catalyst in heavy oil production. In the application, the steam injection well for heavy oil production is a vertical well.

[0042] The beneficial effects of the present invention are as follows:

[0043] 1. The present invention innovatively couples the injection of heavy oil aquathermal cracking catalyst with foam technology, which is divided into two key stages to improve the distribution balance of the catalyst. First, in the steam injection stage, the catalyst and heavy oil are better soluble and in contact with each other through the injection of oil-soluble catalysts, thereby improving the targeting of the catalyst in the formation. Secondly, by utilizing optimized reservoir isolation technology and oil-based foam, in the foam injection stage, the special effects of oil-based foam, such as low density, high fluidity, and no defoaming when encountering oil, are utilized to carry the catalyst upward, weaken the gravity differentiation phenomenon of steam and catalyst, and improve the distribution balance of the catalyst dispersed in the heavy oil in the middle and lower parts of the reservoir in the reservoir, so that the catalyst can be better coupled with steam and give full play to the catalytic reaction. At the same time, steam cross-flow is suppressed, the thermal sweep range of steam is expanded, and the smooth progress of the heavy oil aquathermal cracking reaction is ensured, which significantly improves the modification effect of heavy oil.

[0044] 2. The present invention optimizes the temperature field in the formation and the reaction environment of the catalyst, and improves the overall thermal recovery efficiency. Injecting oil-soluble catalysts and oil-based foams at different stages improves the targeting and distribution uniformity of catalyst migration, reduces the waste of steam and catalysts, reduces production costs, and is widely applicable to thermal recovery development of heavy oil reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a schematic diagram of the use of the system for implementing the method for promoting uniform distribution of heavy oil aquathermal cracking catalyst provided in Example 1;

[0046] Among them, 1. gas storage device; 2. gas flow meter; 3. surfactant storage device; 4. foam generator; 5. first booster device; 6. catalyst storage device; 7. second booster device; 8. steam generator; 9. third booster device; 10. injection well; 11. packer; 12. perforation. DETAILED DESCRIPTION

[0047] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0048] The raw materials and devices used in the embodiments and comparative examples are all commercially available raw materials and devices in the art, and their specific sources are not described in detail here.

[0049] In a first aspect of the present invention, there is provided a method for promoting uniform distribution of a heavy oil aquathermal cracking catalyst, comprising the following steps:

[0050] S1. Selecting an oil-soluble water thermal cracking catalyst and its injection position according to reservoir formation conditions;

[0051] S2. After injecting an oil-soluble water thermal cracking catalyst into the formation from a vertical well, injecting the first stage of steam at the same location and placing a packer;

[0052] S3. injecting oil-based foam and second-stage steam into the perforation sections determined in step S2 below the packer, and removing the packer after the injection is completed;

[0053] S4. After the well is shut down for reaction, the well is opened for steam drive production until the production is completed;

[0054] In step S2, the packer is placed in the middle and lower part of the steam injection perforation section;

[0055] In step S2, if the oil-soluble water thermal cracking catalyst needs a certain amount of time to be converted into a state with catalytic activity in the formation, the well needs to be shut down for treatment after the placement of the packer. For example, hexadecyl trimethylammonium heptamolybdate has catalytic activity only after it is decomposed into molybdenum disulfide, and the time required for the decomposition process is the shut-in time. If the oil-soluble water thermal cracking catalyst itself already has catalytic activity, there is no need to shut down the well for treatment.

[0056] In step S1, the reservoir formation conditions include reservoir thickness, heavy oil reserves in the reservoir, and pore volume in the reservoir;

[0057] The oil-soluble hydrothermal cracking catalyst includes a modified transition metal oxide, a modified transition metal sulfide or a transition metal organic acid salt and a complex thereof having catalytic activity for heavy oil, the transition metal concentration in the oil-soluble hydrothermal cracking catalyst is 20 μg / g-250 μg / g, the catalyst solvent in the oil-soluble hydrothermal cracking catalyst is diesel or catalytic diesel; the catalytic temperature of the oil-soluble hydrothermal cracking catalyst is lower than 300°C. The oil-soluble hydrothermal cracking catalyst can be selected from hexadecyl trimethylammonium heptamolybdate, iron oleate, nickel oleate or nano black card, etc.

[0058] In step S2, the amount of oil-soluble water thermal cracking catalyst used is 0.3wt%-1.5wt% of the heavy oil reserves in the reservoir, the injection amount of the first stage steam is 0.1PV-0.3PV, the injection amount of the first stage steam is measured by liquid water volume, the injection rate of the first stage steam is 100t / d-150t / d, and the temperature of the second stage steam is 250℃-350℃; further preferably, the injection amount of the first stage steam is 0.2PV.

[0059] In step S2, the placement position of the packer is specifically from the vertical middle section of the steam injection perforation section to the bottom end of the perforation section, which accounts for 1 / 4 of the total vertical length of the perforation section. If the perforation section is 1120 meters to 1160 meters underground, the placement position of the packer is from 1140 meters underground (the vertical middle section of the perforation section) to 1150 meters (that is, the bottom end of the perforation section accounts for 1 / 4 of the total vertical length of the perforation section). More preferably, the placement position of the packer is from the bottom end of the perforation section to 1 / 4 of the total vertical length of the perforation section.

[0060] In step S3, the injection volume of the oil-based foam is 0.05PV-0.15PV, the foaming volume of the oil-based foam is ≥150mL, the liquid separation half-life is ≥180s, and the mass of the oil-based foam is 60%-80%, that is, the volume of gas in the oil-based foam accounts for 60%-80% of the total volume of the oil-based foam;

[0061] Oil-based foams consist of gas, surfactants and solvents.

[0062] The gas is selected from N2, CO2, flue gas or other commonly used additive gases in oil fields.

[0063] The surfactant is a single component of a fluorinated surfactant or a silicon-containing surfactant, or a composite component of a fluorinated surfactant or a silicon-containing surfactant and a phosphate ester or Span20.

[0064] The solvent is kerosene or diesel.

[0065] When the surfactant is a single component, the mass ratio of the surfactant to the oil-based foam is 0.3wt%-0.35wt%; when the surfactant is a compound component, the mass ratio of the surfactant to the oil-based foam is 1.5wt%-2.5wt%.

[0066] In step S3, the injection amount of the second stage steam is 0.08PV-0.12PV, the injection amount of the second stage steam is measured by liquid water volume, the injection rate of the second stage steam is 100t / d-150t / d, the temperature of the second stage steam is 250℃-350℃, and the temperature of the second stage steam is higher than the catalytic temperature of the oil-soluble water thermal cracking catalyst injected in step S2.

[0067] In step S3, the injection rate of the second stage steam is 100 t / d and the temperature is 320°C.

[0068] In step S4, the well is shut down for 2 to 5 days. The shut-in time is determined according to the optimal reaction time required for the oil-soluble water thermal cracking catalyst injected in step S2. For example, if the optimal catalytic time of nano black card is 2 days, when nano black card is used as the oil-soluble water thermal cracking catalyst, the well can be shut down for 2 days.

[0069] Preferably, in step S4, the injection rate of steam flooding is 150 t / d and the temperature is 300° C.;

[0070] The condition for the end of production is that the water content in the output fluid is ≥98.5%.

[0071] In a second aspect of the present invention, a system for implementing the above-mentioned method for promoting uniform distribution of heavy oil aquathermal cracking catalyst is provided, comprising an oil-based foam injection module, a catalyst injection module and a steam injection module.

[0072] The oil-injection-based foam module comprises a gas storage device, a surfactant storage device, a foam generator and a first pressurizing device, the gas storage device and the surfactant storage device are connected to the foam generator, a gas flow meter is provided between the gas storage device and the foam generator, and the foam generator is connected to the first pressurizing device;

[0073] The catalyst injection module includes a catalyst storage device and a second pressurizing device connected in sequence;

[0074] The steam injection device comprises a steam generator and a third pressurizing device connected in sequence;

[0075] The first booster device is used to inject oil-based foam into the formation, the second booster device is used to inject catalyst into the formation, and the third booster device is used to inject steam into the formation.

[0076] The third aspect of the present invention provides the use of the above method for promoting uniform distribution of heavy oil aquathermal cracking catalyst or the system for promoting uniform distribution of heavy oil aquathermal cracking catalyst in heavy oil production. In the application, the steam injection well for heavy oil production is a vertical well.

[0077] Example 1

[0078] A system for implementing a method for promoting uniform distribution of a heavy oil aquathermal cracking catalyst, such as Figure 1 As shown, it includes an oil-based foam injection module, a catalyst injection module and a steam injection module.

[0079] The oil-injection-based foam module comprises a gas storage device 1, a surfactant storage device 3, a foam generator 4 and a first pressurizing device 5, wherein the gas storage device 1 and the surfactant storage device 3 are connected to the foam generator 4, a gas flow meter 2 is provided between the gas storage device 1 and the foam generator 4, and the foam generator 4 is connected to the first pressurizing device 5;

[0080] The catalyst injection module comprises a catalyst storage device 6 and a second supercharging device 7 connected in sequence;

[0081] The steam injection device comprises a steam generator 8 and a third booster device 9 connected in sequence;

[0082] The first booster device 5 is used to inject oil-based foam into the formation, the second booster device 7 is used to inject catalyst into the formation, and the third booster device 9 is used to inject steam into the formation. In this embodiment, the first booster device 5, the second booster device 7 and the third booster device 9 are all connected to the injection well 10, the injection well 10 is provided with perforations 12, and the injection well is provided with a packer 11 as needed.

[0083] Example 2

[0084] A method for promoting uniform distribution of a heavy oil aquathermal cracking catalyst, the specific steps of the method are as follows:

[0085] S1. According to the reservoir position of the reservoir formation, the reservoir thickness is 6m, the porosity is 32%, and the permeability is 1700×10 -3 μm 2 , heavy oil reserves are 775 t, and the pore volume in the reservoir is 1235 m 3 In this embodiment, hexadecyl trimethylammonium heptamolybdate is selected as the oil-soluble aquathermolysis catalyst, and the injection position of the oil-soluble aquathermolysis catalyst into the formation is the perforation section of the entire heavy oil reservoir;

[0086] In this embodiment, the concentration of transition metal is 250 μg / g, and the catalyst solvent is diesel;

[0087] S2. After injecting 0.3wt% of the heavy oil reserve mass of hexadecyl trimethylammonium heptamolybdate into the formation from a vertical well, inject 0.1PV of the first stage steam at an injection rate of 150t / d, with a temperature of 350°C, and place a packer at 1 / 4 of the total vertical length of the perforated section at the bottom of the reservoir where the heavy oil is located. Since hexadecyl trimethylammonium heptamolybdate needs to be decomposed in the formation before it can have catalytic activity, the well needs to be shut in for 12 hours after the packer is set, and then the well is opened to continue subsequent operations;

[0088] S3. Inject 0.05PV of oil-based foam and 0.08PV of second-stage steam from the perforation section below the packer. After the injection is completed, remove the packer.

[0089] The second stage steam injection rate is 100t / d and the temperature is 350℃.

[0090] The oil-based foam includes gas, surfactant and solvent. In this embodiment, the gas is N2, the surfactant is a fluorine-containing surfactant accounting for 0.35wt% of the total mass of the oil-based foam, specifically a fluorocarbon polymer C(-R2)(COO-(CH2)N-(CF2-CF2)-R1)-CH2, and the solvent is diesel. When the oil-based foam is evaluated using the Warning-Blender method, the foaming volume is 200mL, the liquid separation half-life is 262s, and the foam quality is 70%;

[0091] S4. After shutting in the well for 5 days, the well is opened for steam drive production from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d, and the temperature is 300℃.

[0092] Example 3

[0093] A method for promoting uniform distribution of a heavy oil aquathermal cracking catalyst, the specific steps of the method are as follows:

[0094] S1. According to the reservoir thickness of 8m, porosity of 30%, and permeability of 1600×10 -3 μm 2 , heavy oil reserves are 750 t, and the pore volume in the reservoir is 1210 m 3 In this embodiment, nano black card is selected as the oil-soluble water thermal cracking catalyst, and the injection position of the oil-soluble water thermal cracking catalyst into the formation is the perforation section of the entire heavy oil reservoir;

[0095] In this embodiment, the concentration of transition metal is 20 μg / g, and the catalyst solvent is diesel;

[0096] S2. After injecting 1.5wt% of the heavy oil reserves into the formation through a vertical well, 0.3PV of the first stage steam is injected at an injection rate of 100t / d at a temperature of 250°C, and a packer is placed in the middle of the perforated section of the heavy oil reservoir, accounting for 1 / 2 of its total vertical length. Since the nano-black card itself has catalytic activity, subsequent operations can be carried out without shutting down the well after the packer is set;

[0097] S3. Inject 0.15PV oil-based foam and 0.12PV second-stage steam from the perforation section below the packer. After the injection is completed, remove the packer.

[0098] The second stage steam injection rate is 150t / d and the temperature is 250℃.

[0099] The oil-based foam includes gas, surfactant and solvent. In this embodiment, the gas is N2, the surfactant is a fluorinated surfactant and a Span20 composite surfactant accounting for 2.5wt% of the total mass of the oil-based foam, wherein the fluorinated surfactant is specifically FSA-99, and the solvent is diesel. When the oil-based foam is evaluated by the Warning-Blender method, the foaming volume is 400mL, the liquid separation half-life is 1200s, and the foam quality is 80%;

[0100] S4. After shutting in the well for reaction for 2 days, the well is opened for steam drive production from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d, and the temperature is 300℃.

[0101] Example 4

[0102] A method for promoting uniform distribution of a heavy oil aquathermal cracking catalyst, the specific steps of the method are as follows:

[0103] S1. According to the reservoir thickness of 10m, porosity of 25%, and permeability of 1800×10 -3 μm 2 , heavy oil reserves are 550 t, and the pore volume in the reservoir is 970 m 3 In this embodiment, iron oleate is selected as the oil-soluble aquathermolysis catalyst, and the injection position of the oil-soluble aquathermolysis catalyst into the formation is the perforated section of the entire heavy oil reservoir;

[0104] In this embodiment, the concentration of transition metal is 100 μg / g, and the catalyst solvent is catalytic wood;

[0105] S2. After injecting 0.8wt% of the heavy oil reserves into the formation from a vertical well, inject 0.1PV of the first stage steam at an injection rate of 150t / d, and place a packer at 1 / 3 of the total vertical length of the perforated section at the bottom of the heavy oil reservoir. Since iron oleate itself has catalytic activity, subsequent operations can be carried out without shutting in the well after setting the packer;

[0106] S3 injects 0.10PV of oil-based foam and 0.10PV of second-stage steam from the perforation section below the packer. After the injection is completed, the packer is removed.

[0107] The second stage steam injection rate is 130t / d and the temperature is 300℃.

[0108] The oil-based foam includes gas, surfactant and solvent. In this embodiment, the gas is N2, the surfactant is a composite surfactant of a silicon-containing surfactant and a phosphate ester accounting for 1.8wt% of the total mass of the oil-based foam, wherein the silicon-containing surfactant is specifically BM-I, and the solvent is kerosene. When the oil-based foam is evaluated by the Warning-Blender method, the foaming volume is 250mL, the liquid separation half-life is 300s, and the foam quality is 60%;

[0109] S4. After shutting in the well for 4 days, the well is opened for steam drive production from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d, and the temperature is 300℃.

[0110] Experimental Example 1

[0111] Under simulated experimental conditions, the heavy oil catalytic aquathermolysis process was used to develop heavy oil reservoirs. The model used was a two-dimensional sand filling oil displacement device. The simulated reservoir temperature was 50°C, the permeability was 5150mD, the oil saturation was 90.8%, the porosity was 35.10%, and the heavy oil viscosity was 2350mPa·s at 50°C. The model outlet back pressure was set to 1MPa, the experimental oil displacement model was 50cm long, 40cm wide, and 1cm deep. The specific operation steps are as follows:

[0112] S1. According to the model parameters, hexadecyl trimethylammonium heptamolybdate is selected as the oil-soluble aquathermolysis catalyst, the injection position of the oil-soluble aquathermolysis catalyst is the perforated section of the entire heavy oil reservoir, the concentration of the transition metal in the catalyst is 250 μg / g, and the catalyst solvent is diesel;

[0113] S2. After injecting 0.3wt% of the heavy oil reserve mass of hexadecyl trimethylammonium heptamolybdate into the formation from a vertical well, inject 0.2PV of the first stage steam at an injection rate of 150t / d at a temperature of 350°C, and place a packer at the 1 / 4 position below the perforated section of the reservoir where the heavy oil is located. Since hexadecyl trimethylammonium heptamolybdate needs to be decomposed in the formation before it can have catalytic activity, the well needs to be shut in for 12 hours after the packer is set. After the well is shut in, the well is opened to continue subsequent operations;

[0114] S3. Inject 0.05PV of oil-based foam and 0.08PV of second-stage steam from the perforation section below the packer. After the injection is completed, remove the packer. The injection rate of the second-stage steam is 100t / d and the temperature is 350℃.

[0115] The oil-based foam includes gas, surfactant and solvent. In this embodiment, the gas is N2, the surfactant is a fluorinated surfactant and a Span20 composite surfactant accounting for 2.5wt% of the total mass of the oil-based foam, wherein the fluorinated surfactant is specifically FSA-99, and the solvent is diesel. When the oil-based foam is evaluated by the Warning-Blender method, the foaming volume is 400mL, the liquid separation half-life is 1200s, and the foam quality is 80%;

[0116] S4. After shutting in the well for reaction for 2 days, the well is opened for steam drive production from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d, and the temperature is 350℃.

[0117] Experimental Example 2

[0118] Under simulated experimental conditions, the heavy oil catalytic aquathermolysis process was used to develop heavy oil reservoirs. The model used was a two-dimensional sand filling oil displacement device. The simulated reservoir temperature was 50°C, the permeability was 5100mD, the oil saturation was 91%, the porosity was 35.5%, and the heavy oil viscosity was 2350mPa·s at 50°C. The model outlet back pressure was set to 1MPa, the experimental oil displacement model was 50cm long, 40cm wide, and 1cm deep. The specific operation steps are as follows:

[0119] S1. The solid particle catalyst obtained by mixing the cracking waste catalyst and quartz sand are filled within 2 cm near the injection well of the model, and the rest of the model is filled with conventional quartz sand. The solid particle catalyst is a waste of platinum group metal catalyst supported by alumina, and the transition metal concentration in the mixture with quartz sand is 250μg / g.

[0120] S2. The well is opened and steam drive is carried out from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d and the temperature is 350℃.

[0121] Experimental Example 3

[0122] Under simulated experimental conditions, the heavy oil catalytic aquathermolysis process was used to develop heavy oil reservoirs. The model used was a two-dimensional sand filling oil displacement device. The simulated reservoir temperature was 50°C, the permeability was 5050mD, the oil saturation was 90.3%, the porosity was 34.5%, and the heavy oil viscosity was 2350mPa·s at 50°C. The model outlet back pressure was set to 1MPa, the experimental oil displacement model was 50cm long, 40cm wide, and 1cm deep. The specific operation steps are as follows:

[0123] S1. According to the model parameters, ammonium tetrathiomolybdate is selected as a water-soluble aquathermolysis catalyst, the injection position of the water-soluble aquathermolysis catalyst into the formation is the perforated section of the entire heavy oil reservoir, the concentration of transition metal in the catalyst is 250 μg / g, and the catalyst solvent is diesel;

[0124] S2. After injecting 0.3wt% of the heavy oil reserve mass of ammonium tetrathiomolybdate into the formation from a vertical well, inject 0.2PV of the first stage steam at an injection rate of 150t / d, the temperature is 350℃, and place a packer at the 1 / 4 position of the lower part of the perforated section of the reservoir where the heavy oil is located. Since hexadecyl trimethylammonium heptamolybdate needs to be decomposed in the formation before it can have catalytic activity, the well needs to be shut in for 12h after the packer is set, and then the well is opened to continue the subsequent operation;

[0125] S3. Inject 0.05PV of oil-based foam and 0.08PV of second-stage steam from the perforation section below the packer. After the injection is completed, remove the packer. The injection rate of the second-stage steam is 100t / d and the temperature is 350℃.

[0126] The oil-based foam includes gas, surfactant and solvent. In this embodiment, the gas is N2, the surfactant is a fluorinated surfactant and a Span20 composite surfactant accounting for 2.5wt% of the total mass of the oil-based foam, wherein the fluorinated surfactant is specifically FSA-99, and the solvent is diesel. When the oil-based foam is evaluated by the Warning-Blender method, the foaming volume is 400mL, the liquid separation half-life is 1200s, and the foam quality is 80%;

[0127] S4. After shutting in the well for reaction for 2 days, the well is opened for steam drive production from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d, and the temperature is 350℃.

[0128] Experimental Example 4

[0129] Under simulated experimental conditions, the heavy oil catalytic aquathermolysis process was used to develop heavy oil reservoirs. The model used was a two-dimensional sand filling oil displacement device. The simulated reservoir temperature was 50°C, the permeability was 5200mD, the oil saturation was 91.5%, the porosity was 36.10%, and the heavy oil viscosity was 2350mPa·s at 50°C. The model outlet back pressure was set to 1MPa, the experimental oil displacement model was 50cm long, 40cm wide, and 1cm deep. The specific operation steps are as follows:

[0130] S1. According to the model parameters, hexadecyl trimethylammonium heptamolybdate is selected as the oil-soluble aquathermolysis catalyst, the injection position of the oil-soluble aquathermolysis catalyst is the perforated section of the entire heavy oil reservoir, the concentration of the transition metal in the catalyst is 250 μg / g, and the catalyst solvent is diesel;

[0131] S2. After injecting 0.3wt% of the heavy oil reserve mass of hexadecyl trimethylammonium heptamolybdate into the formation from a vertical well, inject 0.2PV of the first stage steam at an injection rate of 150t / d at a temperature of 350°C, and place a packer at the 1 / 4 position below the perforated section of the reservoir where the heavy oil is located. Since hexadecyl trimethylammonium heptamolybdate needs to be decomposed in the formation before it can have catalytic activity, the well needs to be shut in for 12 hours after the packer is set. After the well is shut in, the well is opened to continue subsequent operations;

[0132] S3. Inject 0.05PV of oil-based foam and 0.08PV of second-stage steam from the perforation section below the packer. After the injection is completed, remove the packer. The injection rate of the second-stage steam is 100t / d and the temperature is 350℃.

[0133] The oil-based foam includes gas, surfactant and solvent. In this embodiment, the gas is N2, the surfactant is prepared by using a high-stability water-based surfactant system UTL-2, wherein the mass fractions of UT8-2, LS-2024 and P(AM-DMDAAC) are 0.17%, 0.34% and 0.6%, respectively, and the solvent is deionized water. When the water-based foam is evaluated by the Warning-Blender method, the foaming volume is 495 mL, the liquid separation half-life is greater than 30 min, and the foam quality is 80%;

[0134] S4. After shutting in the well for reaction for 2 days, the well is opened for steam drive production from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d, and the temperature is 350℃.

[0135] Experimental Example 5

[0136] Under simulated experimental conditions, the heavy oil catalytic aquathermolysis process was used to develop heavy oil reservoirs. The model used was a two-dimensional sand filling oil displacement device. The simulated reservoir temperature was 50°C, the permeability was 5210mD, the oil saturation was 90.7%, the porosity was 35.6%, and the heavy oil viscosity was 2350mPa·s at 50°C. The model outlet back pressure was set to 1MPa, the experimental oil displacement model was 50cm long, 40cm wide, and 1cm deep. The specific operation steps are as follows:

[0137] S1. According to the model parameters, hexadecyl trimethylammonium heptamolybdate is selected as the oil-soluble aquathermolysis catalyst, the injection position of the oil-soluble aquathermolysis catalyst is the perforated section of the entire heavy oil reservoir, the concentration of the transition metal in the catalyst is 250 μg / g, and the catalyst solvent is diesel;

[0138] S2. After injecting 0.3wt% of the heavy oil reserves into the formation through a vertical well, 0.1PV of the first stage steam was injected at an injection rate of 150t / d at a temperature of 350°C, and the well was shut in for 12h. After shutting in, the well was opened to continue the subsequent operation;

[0139] S3. Inject 0.05 PV of oil-based foam and 0.08 PV of second-stage steam from the entire heavy oil reservoir perforation section, where the injection rate of the second-stage steam is 100 t / d and the temperature is 350°C.

[0140] The oil-based foam includes gas, surfactant and solvent. In this embodiment, the gas is N2, the surfactant is a fluorinated surfactant and a Span20 composite surfactant accounting for 2.5wt% of the total mass of the oil-based foam, wherein the fluorinated surfactant is specifically FSA-99, and the solvent is diesel. When the oil-based foam is evaluated by the Warning-Blender method, the foaming volume is 400mL, the liquid separation half-life is 1200s, and the foam quality is 80%;

[0141] S4. After shutting in the well for reaction for 2 days, the well is opened for steam drive production from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d, and the temperature is 350℃.

[0142] Experimental Example 6

[0143] Under simulated experimental conditions, the heavy oil catalytic aquathermolysis process was used to develop heavy oil reservoirs. The model used was a two-dimensional sand filling oil displacement device. The simulated reservoir temperature was 50°C, the permeability was 5030mD, the oil saturation was 91.3%, the porosity was 35.4%, and the heavy oil viscosity was 2350mPa·s at 50°C. The model outlet back pressure was set to 1MPa, the experimental oil displacement model was 50cm long, 40cm wide, and 1cm deep. The specific operation steps are as follows:

[0144] S1. According to the model parameters, hexadecyl trimethylammonium heptamolybdate is selected as the oil-soluble aquathermolysis catalyst, the injection position of the oil-soluble aquathermolysis catalyst is the perforated section of the entire heavy oil reservoir, the concentration of the transition metal in the catalyst is 250 μg / g, and the catalyst solvent is diesel;

[0145] S2. After injecting 0.3wt% of the heavy oil reserve mass of hexadecyl trimethylammonium heptamolybdate into the formation from a vertical well, inject 0.1PV of the first stage steam at an injection rate of 150t / d at a temperature of 350°C, and place a packer at the 1 / 4 position below the perforated section of the reservoir where the heavy oil is located. Since hexadecyl trimethylammonium heptamolybdate needs to be decomposed in the formation before it can have catalytic activity, subsequent operations are continued after the packer is set;

[0146] S3. Inject 0.05PV of oil-based foam and 0.08PV of second-stage steam from the perforation section below the packer. After the injection is completed, remove the packer. The injection rate of the second-stage steam is 100t / d and the temperature is 350℃.

[0147] The oil-based foam includes gas, surfactant and solvent. In this embodiment, the gas is N2, the surfactant is a fluorinated surfactant and a Span20 composite surfactant accounting for 2.5wt% of the total mass of the oil-based foam, wherein the fluorinated surfactant is specifically FSA-99, and the solvent is diesel. When the oil-based foam is evaluated by the Warning-Blender method, the foaming volume is 400mL, the liquid separation half-life is 1200s, and the foam quality is 80%;

[0148] S4. After shutting in the well for reaction for 2 days, the well is opened for steam drive production from the injection well to the vertical well until the water content in the output fluid is ≥98.5%, and the production is terminated; the injection rate of steam drive is 150t / d, and the temperature is 350℃.

[0149] The experimental results of the above experimental examples are as follows:

[0150] Table 1 Experimental results statistics

[0151]

[0152] Combined with the data in Table 1, the data comparison of Experimental Example 1 and Experimental Example 2 shows that the method provided by the present invention regulates the distribution of the oil-soluble catalyst through oil-based foam. Compared with the underground in-situ catalyst cracking and reforming process of heavy oil in the ground filling method, it increases the sweep efficiency of the catalyst while improving the reforming efficiency and recovery rate of the heavy oil. The key advantage of the ground filling method is the resource utilization of waste, which has strong economy and catalyst targeting, but the catalytic effect and deep extension effect are relatively weak. This method utilizes the special properties of oil-based foam to improve the targeting and distribution uniformity of the catalyst, and the reasonable opening and closing measures also ensure the success rate of the construction method.

[0153] Comparison of the data of Experimental Example 1 and Experimental Example 3 shows that the method provided by the present invention regulates the distribution of the oil-soluble catalyst through oil-based foam, which effectively improves the contact efficiency between the catalyst and the crude oil compared with the use of the oil-soluble catalyst. According to the data in the table, when the sweep efficiency of Experimental Example 3 is not much different from that of Experimental Example 1, the modification effect and recovery rate are significantly lower than those of Experimental Example 1, reflecting that the water-soluble catalyst fails to effectively contact the heavy oil in the reservoir.

[0154] Comparison of the data of Experimental Example 1 and Experimental Example 4 shows that the method provided by the present invention regulates the distribution of the oil-soluble catalyst by oil-based foam, which effectively improves the sweep efficiency of the oil-soluble catalyst compared to regulating the distribution of the oil-soluble catalyst by water-based foam. According to the data in the table, the modification effect of Experimental Example 4 is slightly worse than that of Experimental Example 1, but the sweep efficiency is very different, which also reflects that the oil-based foam is crucial for the distribution balance of the catalyst. Because water-based foam and oil will defoam, the high fluidity characteristics will also disappear after mixing with oil, and it cannot effectively carry the oil-soluble catalyst that is already miscible with crude oil.

[0155] Comparison of the data of Experimental Example 1 and Experimental Example 5 shows that the method provided by the present invention regulates the distribution of the oil-soluble catalyst through the oil-based foam, which effectively improves the sweep efficiency of the oil-soluble catalyst compared to not setting up a packer to control the injection position of the oil-based foam. According to the data in the table, the sweep efficiency, modification effect and recovery rate of Experimental Example 5 are slightly lower than those of Experimental Example 1, indicating that the setting of the packer in the selected layer is closely related to the high efficiency of the measure. This construction method overcomes the uneven distribution of the catalyst caused by gravity differentiation. However, when the oil-based foam is injected in the upper part of the perforation section or the steam perforation section, its density is relatively small, and it cannot effectively contact the catalyst liquid or particles deposited in the middle and lower parts of the heavy oil reservoir, so the effectiveness of the measure cannot be guaranteed.

[0156] Comparison of the data of Experimental Example 1 and Experimental Example 6 shows that the method provided by the present invention regulates the distribution of the oil-soluble catalyst by oil-based foam, and effectively improves the modification effect of the oil-soluble catalyst compared with non-selective well shut-in. According to the data in the table, the sweep efficiency of Experimental Example 6 is basically the same as that of Experimental Example 1, but the modification effect is lower than that of Experimental Example 1, indicating that not selecting well shut-in will result in the modification process of the heavy oil not being fully completed when some oil-based catalysts are used. Because some catalysts do not have catalytic activity in the form of entering the formation, it takes a certain amount of time to decompose and transform.

Claims

1. A method for promoting uniform distribution of a heavy oil aquathermal cracking catalyst, characterized in that: The steps include: S1. Selecting an oil-soluble water thermal cracking catalyst and its injection position according to reservoir formation conditions; S2. After injecting an oil-soluble water thermal cracking catalyst into the formation from a vertical well, injecting the first stage of steam at the same location and placing a packer; S3. injecting oil-based foam and second-stage steam into the perforation sections determined in step S2 below the packer, and removing the packer after the injection is completed; S4. After the well is shut down for reaction, the well is opened for steam drive production until the production is completed; In step S1, the reservoir formation conditions include reservoir thickness, heavy oil reserves in the reservoir, and pore volume in the reservoir; In step S2, the packer is placed in the middle and lower part of the steam injection perforation section; In step S2, if the oil-soluble water thermal cracking catalyst needs a certain time to be converted into a state with catalytic activity in the formation, the well needs to be shut down for treatment after placing the packer; if the oil-soluble water thermal cracking catalyst itself has catalytic activity, then there is no need to shut down the well for treatment; In step S3, the injection volume of the oil-based foam is 0.05PV-0.15PV, the foaming volume of the oil-based foam is ≥150mL, the liquid separation half-life is ≥180s, and the mass of the oil-based foam is 60%-80%, that is, the volume of gas in the oil-based foam accounts for 60%-80% of the total volume of the oil-based foam; Oil-based foams consist of gas, surfactants and solvents. The gas is selected from N2, CO2 or flue gas, The surfactant is a single component of a fluorinated surfactant or a silicon-containing surfactant, or a composite component of a fluorinated surfactant or a silicon-containing surfactant and a phosphate ester or Span20. The solvent is kerosene or diesel; when the surfactant is a single component, the mass ratio of the surfactant to the oil-based foam is 0.3wt%-0.35wt%; when the surfactant is a compound component, the mass ratio of the surfactant to the oil-based foam is 1.5wt%-2.5wt%; The method for promoting uniform distribution of heavy oil aquathermal cracking catalyst is implemented by the following system, which includes an oil-based foam injection module, a catalyst injection module and a steam injection module. The oil-injection-based foam module comprises a gas storage device, a surfactant storage device, a foam generator and a first pressurizing device, the gas storage device and the surfactant storage device are connected to the foam generator, a gas flow meter is provided between the gas storage device and the foam generator, and the foam generator is connected to the first pressurizing device; The catalyst injection module includes a catalyst storage device and a second pressurizing device connected in sequence; The steam injection module comprises a steam generator and a third boosting device connected in sequence; The first booster device is used to inject oil-based foam into the formation, the second booster device is used to inject catalyst into the formation, and the third booster device is used to inject steam into the formation.

2. The method for promoting uniform distribution of heavy oil aquathermal cracking catalyst according to claim 1, characterized in that: The oil-soluble hydrothermal cracking catalyst includes a modified transition metal oxide, a modified transition metal sulfide or a transition metal organic acid salt and a complex thereof having catalytic activity for heavy oil, the transition metal concentration in the oil-soluble hydrothermal cracking catalyst is 20 μg / g-250 μg / g, the catalyst solvent in the oil-soluble hydrothermal cracking catalyst is diesel or catalytic diesel; the catalytic temperature of the oil-soluble hydrothermal cracking catalyst is lower than 300°C.

3. The method for promoting uniform distribution of heavy oil aquathermal cracking catalyst according to claim 1, characterized in that: In step S2, the amount of oil-soluble water thermal cracking catalyst used is 0.3wt%-1.5wt% of the heavy oil reserves in the reservoir, the injection amount of the first stage steam is 0.1PV-0.3PV, the injection amount of the first stage steam is measured by liquid water volume, the injection rate of the first stage steam is 100t / d-150t / d, and the temperature of the second stage steam is 250℃-350℃.

4. The method for promoting uniform distribution of heavy oil aquathermal cracking catalyst according to claim 1, characterized in that: In step S2, the placement position of the packer is specifically from the vertical middle section of the steam injection perforation section to the bottom end of the perforation section, which occupies 1 / 4 of the total vertical length of the perforation section.

5. The method for promoting uniform distribution of heavy oil aquathermal cracking catalyst according to claim 1, characterized in that: In step S3, the injection amount of the second stage steam is 0.08PV-0.12PV, the injection amount of the second stage steam is measured by liquid water volume, the injection rate of the second stage steam is 100t / d-150t / d, the temperature of the second stage steam is 250℃-350℃, and the temperature of the second stage steam is higher than the catalytic temperature of the oil-soluble water thermal cracking catalyst injected in step S2.

6. The method for promoting uniform distribution of heavy oil aquathermal cracking catalyst according to claim 1, characterized in that: In step S4, the well is shut down for 2 to 5 days; In step S4, the injection rate of steam flooding is 150 t / d and the temperature is 300°C; The condition for the end of production is that the water content in the output fluid is ≥98.5%.

7. Use of the method for promoting uniform distribution of heavy oil aquathermolysis catalyst according to any one of claims 1 to 6 in heavy oil production, wherein the steam injection well for heavy oil production is a vertical well.

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