Steam enhanced thermal reaction apparatus and method for oil recovery

Abstract

This invention discloses a steam-enhanced thermal reaction device and method for oil production, relating to the field of petrochemical technology. The invention involves a chemical reaction within a reactor's reaction unit, with the heat generated used to heat steam in a steam channel. By organically combining multiple chemical reactors with a steam system, the synergistic effect of the exothermic chemical reaction and the heat generated by the steam significantly improves reservoir heating efficiency. This device is particularly suitable for the extraction of heavy oil, extra-heavy oil, and oil sands, offering advantages such as high reaction efficiency, good thermal energy utilization, and flexible operation. Practical application has shown that this invention utilizes a multi-chemical reactor within the wellbore, combined with a steam-enhanced thermal reaction device, for catalytically heated oil sands extraction. This device and method have a wide range of applications, suitable for deep, complex, and low-grade oil reservoirs.

Description

Technical Field

[0001] This invention relates to the field of petrochemical technology, and more specifically, to a steam-enhanced thermal reaction apparatus and method for oil extraction. Background Technology

[0002] Oil sands are sandy deposits containing crude oil, primarily composed of bitumen, water, clay, and sand. According to the classification standards recommended by the United Nations Training and Research Agency (UNITAR), bitumen refers to degassed crude oil with a viscosity greater than 10,000 mPa·s at the original reservoir temperature or a density greater than 1,000 kg / m³ at 15.6 °C and atmospheric pressure. 3 Crude oil. Due to its high content of gum and asphaltene, it has high viscosity and poor fluidity, which also increases the difficulty of its extraction, development costs, and large amounts of CO2 emissions.

[0003] Depending on the specific conditions of the oil sands deposits, the internationally accepted extraction methods typically include open-pit mining, circulating steam stimulation (CSS), solvent-assisted extraction (VAPEX), and steam-assisted gravity drainage (SAGD). Each oil sands extraction technology has its own advantages and disadvantages. Open-pit mining is a mature technology with a recovery rate reaching 90%, but it severely damages the surface ecosystem, and tailings ponds are difficult to manage in the long term. CSS technology is suitable for shallow, tight oil sands, but its recovery rate is relatively low (approximately 25%-35%), requiring multiple cycles. VAPEX technology is currently in the experimental stage and can effectively reduce energy consumption by 30%, but solvent recovery costs are high. SAGD technology is the mainstream technology for deep oil sands (>200 meters), but it consumes large amounts of natural gas and water resources. Furthermore, heat loss is significant during steam injection, with bottomhole steam dryness typically less than 50%. To maintain effective steam dryness and heat, high-temperature steam needs to be generated on the surface and injected into the bottomhole to heat the reservoir, a process that releases a large amount of CO2. Moreover, SAGD technology has low thermal efficiency and poor extraction effect in reservoirs with thin layers, poor physical properties, edge and bottom water, and interlayers. SAGD also has problems such as low oil-gas ratio, large heat loss, and large investment.

[0004] Chinese invention patent application CN114658403A discloses an experimental apparatus and method for simulating multidimensional chemical reactions in porous media. The apparatus includes an injection unit, a model unit, a production unit, and an electric heating unit. The model unit simulates the effects of multidimensional chemical reactions in porous media, while the electric heating unit facilitates the chemical reaction of a multidimensional chemical catalyst, using the generated heat for oil displacement. This invention effectively utilizes the heat released from the chemical reaction, reducing external heat input and improving oil displacement efficiency. However, it suffers from problems such as high energy consumption of the electric heating unit, inconvenient operation, and safety hazards.

[0005] Therefore, there is an urgent need to develop downhole operating equipment and processes for oil production in order to reduce extraction costs while significantly increasing oil sands recovery rates.

[0006] In view of this, the present invention is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide a steam-enhanced thermal reaction device and method for oil extraction, which aims to reduce extraction costs while significantly increasing oil sands recovery rate.

[0008] This invention is implemented as follows: In a first aspect, the present invention provides a steam-enhanced thermal reaction apparatus for oil extraction, comprising: The well shaft has a top plate and a bottom plate connected to it, and both the top plate and the bottom plate are sealed to the well shaft. An air inlet is provided on the top plate and an air outlet is provided on the bottom plate. The reactor is located inside the well shaft and includes a feeding unit, a reaction unit, and a production unit. The inlet of the reaction unit is connected to the feeding unit, and the outlet of the reaction unit is connected to the production unit. A steam channel is formed between the outer wall of the reactor and the inner wall of the well shaft. The heat released by the reaction of the raw materials in the reaction unit is used to heat the steam in the steam channel. The steam enters the steam channel through the inlet, is heated by the steam channel, and is then output through the outlet to the production unit to mix with the products of the reaction unit.

[0009] In an optional embodiment, a reaction channel is provided inside the reaction unit, and the reaction channel is filled with a catalyst.

[0010] In an optional embodiment, the catalyst is selected from at least one of metal oxide catalysts and molecular sieve catalysts; And / or, the reaction unit consists of at least one reaction tube, the length of which is 1m-10m.

[0011] In an optional embodiment, the feeding unit is located at the top of the reactor, and the top of the feeding unit is provided with a feed inlet to inject reaction gas into the reaction unit through the feed inlet.

[0012] In an optional embodiment, a gas distributor is provided inside the feed inlet.

[0013] In an optional implementation, the wellbore is located in either the vertical shaft portion or the horizontal shaft portion of the gas injection well; And / or, there are multiple air intakes, distributed at the edge of the top plate; And / or, the top and bottom plates are connected to the reactor via multiple flanges, and the top and bottom plates are connected to the wellbore via multiple flanges; And / or, it also includes temperature and pressure sensors for real-time monitoring of temperature and pressure inside the reactor and in the steam passage.

[0014] Secondly, the present invention provides an oil extraction method, which uses any of the steam-enhanced thermal reaction devices for oil extraction in the foregoing embodiments to treat steam, the steps of which are as follows: Steam is introduced into the steam channel through the air inlet on the top plate to preheat the reactor; The reaction gas is injected into the reactor through the feed unit. The reaction gas undergoes a chemical reaction in the reaction unit and generates heat. The heat released by the reaction is absorbed by the steam in the steam channel. After the steam is heated, it is output from the vent on the bottom plate and enters the production unit to mix with the products from the reaction unit and then injected into the reservoir.

[0015] In an optional embodiment, the steam temperature introduced into the steam passage is 250°C-350°C; And / or, the introduced steam is selected from at least one of saturated steam and superheated steam; And / or, the oil product to be extracted is selected from at least one of heavy oil, extra-heavy oil and oil sands.

[0016] In an optional embodiment, the reactant gas is selected from at least one of hydrogen, carbon monoxide, carbon dioxide, and low-carbon hydrocarbon gases.

[0017] In an optional embodiment, the reaction gas is a mixture of hydrogen and carbon monoxide, with a volume ratio of hydrogen to carbon monoxide of (1-5):1. And / or, the volume ratio of the introduced steam to the reactant gas is (10-90):100.

[0018] This invention offers the following advantages: The chemical reaction takes place within the reactor's reaction unit, and the heat generated is used to heat steam in the steam channel. By organically combining multiple chemical reactors with a steam system, the synergistic effect of the exothermic chemical reaction and the heat generated by the steam significantly improves reservoir heating efficiency. This device is particularly suitable for the extraction of heavy oil, extra-heavy oil, and oil sands, offering advantages such as high reaction efficiency, good thermal energy utilization, and flexible operation.

[0019] Through practice, this invention utilizes a reaction device with multiple chemical reactors in the wellbore and steam-enhanced heating for catalytic thermal extraction of oil sands. This device and method have a wide range of applications and can be used in deep, complex, and low-grade oil reservoirs. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A front view of a steam-enhanced thermal reactor used for oil extraction; Figure 2 A top view of a steam-enhanced thermal reactor used for oil extraction; Figure 3 Front view of the reactor layout well.

[0022] Icons: 1-Reactor; 2-Well shaft; 3-Top plate; 4-Bottom plate; 5-Steam channel; 11-Feed unit; 12-Reaction unit; 13-Production unit; 111-Feed inlet; 112-Gas distributor; 121-Reaction channel; 131-Product outlet; 31-Gas inlet. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0024] This invention organically combines multiple chemical reactors with a steam system, significantly improving reservoir heating efficiency through the synergistic effect of exothermic chemical reactions and thermal steam. This device is particularly suitable for the extraction of heavy oil, extra-heavy oil, and oil sands, offering advantages such as high reaction efficiency, good thermal energy utilization, and flexible operation.

[0025] This invention provides a steam-enhanced thermal reaction device for oil extraction, such as... Figures 1-3 As shown, the system includes a reactor 1 and a wellbore 2. The reactor 1 is located inside the wellbore 2, and a steam channel 5 is formed between the outer wall of the reactor 1 and the inner wall of the wellbore 2. The reactor 1 is used to carry out multiple chemical reactions that release heat. The steam introduced into the steam channel 5 absorbs heat to increase the temperature and dryness of the steam. It is then mixed with the reaction products output from the reactor 1 and enters the reservoir to increase the reservoir temperature and crude oil fluidity.

[0026] This invention significantly improves thermal energy utilization efficiency through the synergistic effect of multiple exothermic chemical reactions and steam injection. It can also reduce oil sand viscosity, improve crude oil fluidity, and greatly increase oil sand recovery rate. The reactor 1 is located in the wellbore 2. By introducing multiple exothermic chemical reactions, the temperature and dryness of the steam are increased, which can reduce steam consumption, energy consumption and carbon emissions, and reduce extraction costs.

[0027] A top plate 3 and a bottom plate 4 are connected to the shaft 2, and both the top plate 3 and the bottom plate 4 are sealed to the inner wall of the shaft 2. The reactor 1 is installed in the space formed between the top plate 3 and the bottom plate 4, and the reactor 1 and the shaft 2 are connected by the top plate 3 and the bottom plate 4. Figure 1 and Figure 2 As shown, the top plate 3 is provided with multiple air inlets 31, distributed along the edges of the top plate 3; the bottom plate 4 is provided with air outlets. High-temperature steam enters the steam channel 5 through the air inlets 31 for heating, and then exits through the air outlets on the bottom plate 4. Specifically, both the top plate 3 and the bottom plate 4 can be porous or have other sieve-like perforations to allow the flow of steam and reaction products. The sealing connection between the top plate 3, the bottom plate 4, and the inner wall of the wellbore 2 is not limited; for example, flange connections can be used. Specifically, the top plate 3 and the bottom plate 4 are connected to the reactor 1 through multiple flanges, and the top plate 3 and the bottom plate 4 are connected to the wellbore 2 through multiple flanges, ensuring the sealing and disassembly of the device. A modular flange connection structure is adopted to facilitate installation, disassembly, and maintenance. The wellbore 2 can be located in the vertical or horizontal section of the gas injection well to adapt to different reservoir development needs.

[0028] Reactor 1 is located inside wellbore 2. Reactor 1 includes a feed unit 11, a reaction unit 12, and a production unit 13, which are connected sequentially via pipelines. The inlet of reaction unit 12 is connected to feed unit 11, and the outlet of reaction unit 12 is connected to production unit 13. The reactants enter reaction unit 12 from feed unit 11 to react. The heat generated by the reaction is absorbed by steam in steam channel 5. Production unit 13 is used to collect the reacted material and discharge the reacted material from reactor 1 through product outlet 131, and together with the steam, it is introduced into the oil reservoir.

[0029] The exothermic reaction of the raw materials in reaction unit 12 is used to heat the steam in steam channel 5. The steam enters steam channel 5 through the inlet, is heated by steam channel 5, and is then output through the outlet to the production unit 13 to mix with the products after the reaction in reaction unit 12.

[0030] In some embodiments, a reaction channel 121 is provided inside the reaction unit 12, and the reaction channel 121 is filled with a catalyst. The catalyst in the reaction channel 121 is used to catalyze the reaction. The structure of the reaction channel 121 is not limited and can be adjusted according to different reaction raw materials. For example, the reaction unit 12 can be composed of at least one reaction tube with a length of 1m-10m, such as 1m, 2m, 3m, 4m, 5m, 6m, 7m, 8m, 9m, 10m, etc., to adapt to different well depths and reaction requirements. Specifically, multiple reaction channels 121 can be uniformly arranged in a tubular configuration.

[0031] Catalysts are used to promote multiple chemical reactions and improve thermal efficiency. There are no restrictions on the type of catalyst. For example, the catalyst can be selected from at least one of metal oxide catalysts and molecular sieve catalysts. That is, the catalyst can be a metal oxide catalyst (such as an iron-based catalyst), a molecular sieve catalyst, or a composite catalyst formed by metal oxide catalysts and molecular sieve catalysts.

[0032] Furthermore, the feeding unit 11 is disposed at the top of the reactor 1, and the top of the feeding unit 11 is provided with a feed inlet 111 to inject the reaction gas into the reaction unit 12 through the feed inlet 111. A gas distributor 112 is disposed inside the feed inlet 111 to uniformly distribute the reaction gas and improve the reaction efficiency. The gas distributor 112 is an existing device, and its structure and principle can be found in the prior art.

[0033] In some embodiments, the steam-enhanced thermal reactor for oil extraction further includes temperature and pressure sensors for real-time monitoring of the temperature and pressure inside the reactor 1 and the steam channel 5 to optimize reaction conditions. The inclusion of temperature and pressure sensors facilitates real-time monitoring and control of the system, ensuring the safety and stability of the reaction process.

[0034] The steam-enhanced thermal reactor for oil production provided by this invention is adaptable to different well types and reservoir conditions, and has a wide range of applications. It can be simultaneously installed in the vertical or horizontal sections of injection wells, allowing for multi-point positioning control as needed based on reservoir conditions. In practice, the method of catalytically generating heat to extract oil sands using a multi-chemical reactor within the wellbore, in conjunction with a steam-enhanced thermal reactor, has a wide range of applications and can be used in deep, complex, and low-grade reservoirs.

[0035] The steam-enhanced thermal reaction device for oil extraction provided in this embodiment of the invention can be made of high-temperature and corrosion-resistant materials to ensure long-term stable operation under high-temperature and high-pressure environments.

[0036] This invention also provides an oil recovery method, which uses a steam-enhanced thermal reaction device for oil recovery provided in this invention to process steam and uses steam-assisted gravity drainage (SAGD) for oil extraction. This invention can significantly improve crude oil recovery rate by optimizing the device and process parameters.

[0037] The specific steps are divided into the following three stages: (1) Steam is introduced into the steam channel 5 through the air inlet on the top plate 3 to preheat the reactor 1; (2) Reaction gas is injected into the reactor 1 through the feed unit 11 of the reactor 1. The reaction gas undergoes a chemical reaction in the reaction unit 12 and generates heat. The heat released by the reaction is absorbed by the steam in the steam channel 5; (3) After the steam is heated, it is output from the air outlet on the bottom plate 4 and enters the production unit 13 to mix with the product after the reaction in the reaction unit 12 and inject it into the reservoir.

[0038] In some embodiments, the introduced steam is selected from at least one of saturated steam and superheated steam, and the steam can be any one or more of the above, specifically all of which can be water vapor. The steam temperature introduced into steam channel 5 is 250℃-350℃, such as 250℃, 260℃, 270℃, 280℃, 290℃, 300℃, 310℃, 320℃, 330℃, 340℃, 350℃, etc. Introducing steam into steam channel 5 has two functions: firstly, it provides the initial reaction temperature for the multi-chemical reactor; secondly, it can carry a large amount of reaction heat into the reservoir, preventing localized heat release in the multi-chemical reactor, thereby achieving targeted regulation of thermal hydrocarbon synergy.

[0039] In some embodiments, the apparatus provided by this invention is applicable to various multi-chemical reactions, including methanation, low-temperature methanol synthesis, Fischer-Tropsch synthesis, and olefin addition reactions. In this embodiment, the multi-chemical reaction is one or more of the above-mentioned reactions. Specifically, the reaction gas is selected from at least one of hydrogen, carbon monoxide, carbon dioxide, and low-carbon hydrocarbon gases, and the reaction gas can be any one or more of the above. The reaction gas enters the catalyst of the reaction unit 12 through the feed unit 11, and through the exothermic multi-chemical reaction, a hydrocarbon generation exothermic effect is achieved. The released heat further increases the temperature and dryness of the steam, and the generated hydrocarbon products enter the reservoir with the steam to reduce viscosity.

[0040] In a preferred embodiment, the reactant gas is a mixture of hydrogen and carbon monoxide, with a volume ratio of hydrogen to carbon monoxide of (1-5):1, such as 1:1, 2:1, 3:1, 4:1, 5:1, etc. The volume ratio of the introduced steam to the reactant gas is (10-90):100, such as 10:100, 20:100, 30:100, 40:100, 50:100, 60:100, 70:100, 80:100, 90:100, etc.

[0041] Furthermore, the apparatus provided in this embodiment of the invention is applicable to the extraction of heavy oil, extra-heavy oil, and oil sands. Through the synergistic effect of multiple chemical reactions generating hydrocarbons and releasing heat with steam, it significantly improves crude oil recovery. Generally, heavy oil has a viscosity of 50-10000 mPa·s and an API gravity of 10-20°; extra-heavy oil has a viscosity >10,000 mPa·s and an API gravity <10°.

[0042] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0043] Example 1 This embodiment provides a steam-enhanced thermal reaction device for oil extraction, such as... Figures 1-3As shown, the reaction apparatus includes a reactor 1, a wellbore 2, a top plate 3, and a bottom plate 4. The horizontal section of the wellbore 2 is located in the oil sand layer. The reactor 1 is fixed to the center of the wellbore 2 by multiple connectors, forming an annular gap between the reactor and the wellbore, i.e., a steam channel 5. The reactor 1 includes a feed unit 11, a reaction unit 12, and a production unit 13 from top to bottom. The feed unit 11 has a feed inlet 111 at the top, which is connected to a continuous tubing extending from the surface to the wellbore for transporting feed gas. The feed unit 11 is equipped with a gas distributor 112. The reaction unit 12 adopts a tubular fixed bed structure, with 20 parallel reaction tubes (reaction channels 121) evenly arranged inside. The reactor is filled with an iron-based Fischer-Tropsch synthesis catalyst supported on ZnO. The production unit 13 has a product outlet 131 at the bottom. Both the top plate 3 and the bottom plate 4 have multiple through holes. The top plate 3 is used to inject steam into the steam channel 5, and the bottom plate 4 is used to mix the reaction products with the steam before they enter the reservoir.

[0044] First, superheated steam (230 °C, 75% dryness) is injected from the ground through the top plate 3 into the annular void at a flow rate of 300 tons per day. The steam preheats reactor 1 as it flows through the annular void. After the system temperature stabilizes, syngas feedstock with a composition of H2:CO = 67:33 (molar ratio) is injected into the reactor through a continuous oil pipe and feed inlet 111. The volume ratio of the introduced steam to the reactant gas is 50:100. The feedstock gas is evenly distributed to each reaction channel 121 via gas distributor 112. The feedstock gas undergoes an exothermic Fischer-Tropsch synthesis reaction under the action of an iron-based catalyst. The heat released by the reaction is absorbed by the steam in the annular void. The hydrocarbon products generated (mainly C5-C20 light oil) are mixed with the high-temperature, high-dryness steam at the production unit 13 and the bottom plate 4 before being injected into the reservoir. The light hydrocarbons effectively dilute the asphaltene, reducing the viscosity of the heavy oil, while the high-temperature steam provides the driving energy.

[0045] Example 2 The basic structure of the device is the same as in Example 1. The main difference is that the wellbore 2 is the casing of a vertical injection well; the reactor 1 is modularly connected in series, and the total length is determined according to the oil layer thickness. The reaction channel 121 of the reaction unit 12 is filled with a nickel-based methanation catalyst supported on Al2O3. Steam is injected to preheat the system at a temperature of 250 °C. Feed gas with a composition of H2:CO = 75:25 (molar ratio) is injected through the feed unit 11. The feed gas undergoes a strongly exothermic methanation reaction on the catalyst (CO + 3H2 → CH4 + 2H2O, ΔH = -165 kJ / mol). The heat of reaction is absorbed by the steam, significantly increasing its enthalpy. The methane (CH4) generated by the reaction acts as an effective solvent gas, which, along with the high-temperature steam, is injected into the reservoir, not only replenishing formation energy but also significantly reducing the viscosity of the crude oil.

[0046] Example 3 The basic structure of the apparatus is the same as in Example 1. The main difference is that the reaction channel 121 of reaction unit 12 is filled with a CuZnZr / ZSM-5 bifunctional catalyst. Steam is injected to preheat the system at a temperature of 250 °C. Feed gas with a composition of H2:CO = 67:33 (molar ratio) is injected through feed unit 11. The feed gas undergoes a synthesis gas to dimethyl ether reaction on the catalyst (2CO + 4H2 → CH3OCH3 + H2O, ΔH = -204.9 kJ / mol). The heat of reaction is absorbed by the steam, significantly increasing its enthalpy. The dimethyl ether (CH3OCH3) produced by the reaction acts as an effective solvent gas, and when injected into the reservoir along with the high-temperature steam, it not only replenishes formation energy but also significantly reduces crude oil viscosity.

[0047] Example 4 The basic structure of the device is the same as in Example 1. The reaction channel 121 of reaction unit 12 is filled with a FeAl / SSZ13 bifunctional catalyst. Steam is injected to preheat the system at a temperature of 300 °C. Feed gas with a composition of H2:CO = 70:30 (molar ratio) is injected through feed unit 11. The feed gas undergoes a synthesis gas to liquefied petroleum gas reaction on the catalyst. The heat of reaction is absorbed by the steam, significantly increasing its enthalpy. The propane and butane produced in the reaction, as effective solvent gases, are injected into the reservoir along with the high-temperature steam, not only replenishing formation energy but also significantly reducing crude oil viscosity.

[0048] Example 5 The only difference from Example 1 is the type of reactant gas injected into the reactor through inlet 111. This example utilizes captured CO2 and green hydrogen (H2) as reactant gases to simulate carbon recycling. The injected feed gas composition is H2:CO2 = 75:25 (molar ratio). The reaction channel 121 of reaction unit 12 is filled with a methanation catalyst with Ni / Al2O3 as the active component. At 300°C, CO2 and H2 undergo a strongly exothermic methanation reaction (CO2 + 4H2 → CH4 + 2H2O, ΔH = -165 kJ / mol). The high-temperature CH4 generated by the reaction is mixed with steam and injected into the reservoir, achieving thermal recovery while converting the greenhouse gas CO2 into useful fuel and storing it underground.

[0049] Example 6 The only difference from Example 1 is the type of reactant gas injected into the reactor through inlet 111: the reactant gas injected into the reactor through inlet 111 is a mixture of methane (CH4) and carbon dioxide (CO2) in a volume ratio of 1:1. The reaction channel 121 of reaction unit 12 is filled with a Ni-Ce / ZSM-5 catalyst. Steam is injected to preheat the system at a temperature of 350°C. The feed gas undergoes a dry reforming reaction on the catalyst (CH4 + CO2 → 2CO + 2H2, ΔH = +247 kJ / mol), which is a strongly endothermic reaction. However, the device continuously supplies heat through the steam channel, transforming the endothermic reaction into stable operation. The generated high-temperature synthesis gas (CO + H2) is injected into the reservoir with the steam, significantly improving the quality and reducing the viscosity of heavy oil.

[0050] Example 7 The only difference from Example 1 is that the volume ratio of the introduced steam to the reactant gas is 100:100.

[0051] Example 8 The only difference from Example 1 is that the volume ratio of the introduced steam to the reactant gas is 1:100.

[0052] Comparative Example 1 In an adjacent well within the same reservoir as in Example 1, steam was injected into the reservoir solely through the casing; no reaction equipment was installed in the wellbore, and no reaction gas was introduced. The steam parameters (temperature, dryness, pressure, and flow rate) were identical to the injection conditions in Example 1.

[0053] Comparative Example 2 A chemical reactor was installed in the same well as in Example 1, but steam injection was shut off, and the annular void was a static air layer. Only the same feed gas as in Example 1 was injected into the reactor, and the initial heat for the reaction was provided by an electric heater.

[0054] Comparative Example 3 The same reaction apparatus was installed in the same well as in Example 1, but no catalyst was loaded into the reaction channel 121 of reaction unit 12. Other operating conditions were exactly the same as in Example 1 (injection of 230 °C steam and synthesis gas).

[0055] Experimental Example 1 The oil recovery effects of the test examples and comparative examples are shown in Table 1.

[0056] Test Method: A three-dimensional physical simulation experimental system was used for testing. The apparatus and process parameters of the examples and comparative examples were applied to model wells filled with cores of the target oil reservoir (oil sands). The model dimensions were 600mm (length) × 300mm (width) × 400mm (height), simulating the injection-production well pattern. Working medium was injected at the injection end according to the conditions of each example, while a constant bottomhole flowing pressure was maintained at the production end. The oil production and water production at the production end were recorded in real time, and the recovery rate (%) was calculated. Simultaneously, thermocouples were placed at the reactor inlet and outlet and inside the model to measure and calculate the heat release (KJ / Kg syngas). Steam dryness was obtained through online sampling and thermodynamic calculations. The steam outlet temperature was the measured temperature of the bottomhole mixed fluid before entering the reservoir. Each experiment was repeated three times, and the average value was taken.

[0057] Table 1. Process Comparison of Examples and Comparative Examples

[0058] It can be seen that the embodiments of the present invention can significantly improve the oil recovery rate compared to the comparative examples. Embodiments (1-7) of the present invention, compared to the comparative examples, can significantly improve the steam outlet temperature, dryness, and oil recovery rate. Examples 8, Comparative Examples 2, and 3, from different perspectives, verify the key roles of the technical features of the present invention, such as the synergistic effect of steam and chemical reaction and the necessity of the catalyst.

[0059] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A steam-enhanced thermal reaction device for oil extraction, characterized in that, include: A well shaft, on which a top plate and a bottom plate are connected, and both the top plate and the bottom plate are sealed to the well shaft; an air inlet is provided on the top plate and an air outlet is provided on the bottom plate; A reactor is located inside the well shaft. The reactor includes a feeding unit, a reaction unit, and a production unit. The inlet of the reaction unit is connected to the feeding unit, and the outlet of the reaction unit is connected to the production unit. A steam channel is formed between the outer wall of the reactor and the inner wall of the well shaft. The exothermic reaction of the raw materials in the reaction unit is used to heat the steam in the steam channel. The steam enters the steam channel through the air inlet, is heated by the steam channel, and then exits through the air outlet into the production unit to mix with the products of the reaction unit.

2. The steam-enhanced thermal reaction apparatus for oil extraction according to claim 1, characterized in that, The reaction unit is equipped with a reaction channel, which is filled with a catalyst.

3. The steam-enhanced thermal reaction apparatus for oil extraction according to claim 2, characterized in that, The catalyst is selected from at least one of metal oxide catalysts and molecular sieve catalysts; And / or, the reaction unit consists of at least one reaction tube, the length of which is 1m-10m.

4. The steam-enhanced thermal reaction apparatus for oil extraction according to claim 1, characterized in that, The feeding unit is located at the top of the reactor, and the top of the feeding unit is provided with a feed inlet to inject reaction gas into the reaction unit through the feed inlet.

5. The steam-enhanced thermal reaction apparatus for oil extraction according to claim 4, characterized in that, A gas distributor is installed inside the feed inlet.

6. The steam-enhanced thermal reaction apparatus for oil extraction according to claim 1, characterized in that, The wellbore is located in the vertical or horizontal section of the gas injection well; And / or, there are multiple air inlets, which are distributed at the edge of the top plate; And / or, the top plate and the bottom plate are connected to the reactor via multiple flanges, and the top plate and the bottom plate are connected to the wellbore via multiple flanges; And / or, it also includes temperature sensors and pressure sensors for real-time monitoring of the temperature and pressure inside the reactor and the steam passage.

7. An oil extraction method, characterized in that, The steam is treated using the steam-enhanced thermal reactor for oil extraction as described in any one of claims 1-6, with the following steps: Steam is introduced into the steam channel through the air inlet on the top plate to preheat the reactor; The reaction gas is injected into the reactor through the feed unit. The reaction gas undergoes a chemical reaction in the reaction unit and generates heat. The heat released by the reaction is absorbed by the steam in the steam channel. After the steam is heated, it is output from the vent on the bottom plate and enters the production unit to mix with the products of the reaction unit and then injected into the oil reservoir.

8. The oil extraction method according to claim 7, characterized in that, The temperature of the steam introduced into the steam channel is 250℃-350℃; And / or, the introduced steam is selected from at least one of saturated steam and superheated steam; And / or, the oil product to be extracted is selected from at least one of heavy oil, extra-heavy oil and oil sands.

9. The oil extraction method according to claim 7, characterized in that, The reactant gas is selected from at least one of hydrogen, carbon monoxide, carbon dioxide, and low-carbon hydrocarbon gases.

10. The oil extraction method according to claim 9, characterized in that, The reactant gas is a mixture of hydrogen and carbon monoxide, with a volume ratio of hydrogen to carbon monoxide of (1-5):

1. And / or, the volume ratio of the introduced steam to the reactant gas is (10-90):100.

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