Heavy oil thermal recovery steam injection device and heavy oil thermal recovery method

Abstract

The present invention relates to the technical field of heavy oil recovery equipment, and in particular to a heavy oil thermal recovery steam injection device and a heavy oil thermal recovery method, comprising a high-temperature steam generator, a high-temperature steam pipeline, a delivery pump, a biomass liquefaction pipe and a biomass delivery pipe. The high-temperature steam generator is used to generate steam. The high-temperature steam pipeline is placed in a wellbore and is used to receive the steam generated by the high-temperature steam generator. The delivery pump is used to transport biomass. The biomass liquefaction pipe is placed in the high-temperature steam pipeline. The biomass delivery pipe is used to receive the biomass transported by the delivery pump and is located in the biomass liquefaction pipe. The device of the present invention is used for heavy oil recovery and improves recovery efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of heavy oil recovery equipment, and in particular to a heavy oil thermal recovery steam injection device and a heavy oil thermal recovery method. Background Art

[0002] In the field of oil production, heavy oil is an important crude oil resource and is irreplaceable. my country's crude oil production is high, but heavy oil extraction is difficult and requires advanced oil extraction technology. With the development of social economy, the research and application of heavy oil extraction technology has been continuously deepened, aiming to improve oil extraction efficiency and reduce energy consumption. Heavy oil in-situ extraction technology is a method of extracting crude oil from heavy oil reservoirs using underground thermal energy or other means. This technology can be divided into two categories: thermal extraction and non-thermal extraction.

[0003] Thermal recovery technologies mainly include steam stimulation (Steam Assisted Gravity Drainage, SAGD) (Zeng Quanshu, Wang Zhiming, Sun Liwei, Gao Qingchun, Tang Aichun. Steam stimulation effect and water breakthrough time prediction considering anisotropy [J]. Fault Block Oil and Gas Field, 2022, Vol. 29 (3): 395-398, 403), steam assisted gravity drainage (Cyclic Steam Stimulation, CSS) (Gao Yunfeng, Fan Tingen, Gao Jinghuai, Li Hui, Dong Hongchao, Ma Shigang, Yue Qingfeng. Steam chamber monitoring of steam assisted gravity drainage based on temperature-sensitive characteristics of oil sands [J]. Petroleum Exploration and Development, 2021, Vol. 48 (6): 1224-1231), steam flooding (Steam These technologies reduce the viscosity of heavy oil by injecting high-temperature and high-pressure steam or heat medium to improve the fluidity of crude oil, but they also have many defects. First, the energy consumption is large, requiring a large amount of thermal energy to heat the reservoir, consuming fuel or electricity, and bringing economic and environmental burdens. Second, the cost is high. The implementation of the technology requires the construction of complex equipment and infrastructure, such as steam generation devices, steam injection wells and oil production wells, which increases the cost of the project. In addition, heavy oil in-situ thermal recovery technology requires a large amount of water to generate steam or as a solvent, which may cause water supply problems in areas with water shortages, affecting the local ecological environment and social sustainable development. The gradual loss of heat during thermal recovery will lead to a decrease in energy efficiency. At the same time, the emission of greenhouse gases such as carbon dioxide generated by fuel combustion and thermal recovery also has a negative impact on climate change. Finally, the geological challenges during the mining process cannot be ignored, as it can easily damage the strata and cause them to collapse.

[0004] Non-thermal recovery technologies mainly include solvent assisted biten extraction (SABER) (Li Mu, Ma Dabo, Bian Fangxia. Steam solvent injection test of heavy oil in Lengjiabao oilfield [J]. Special Oil and Gas Reservoirs, 1995, (2): 50-55), extrusion oil extraction (VAPEX), etc. These technologies change the properties of crude oil, reduce viscosity, promote flow, and achieve oil recovery by injecting solvents or diluents. However, compared with thermal recovery technology, non-thermal recovery technology has a lower recovery rate. The high viscosity of heavy oil limits the effectiveness of non-thermal recovery technology in improving fluidity and enhancing recovery. Compared with thermal recovery technology, non-thermal recovery technology requires more process and equipment investment, such as the use of large amounts of solvents and chemicals, involving complex injection and displacement processes, thereby increasing oil recovery costs. Some non-thermal recovery technologies may use solvents or chemicals, which have potential negative impacts on the environment. Solvents involve storage and handling issues, and chemicals may cause groundwater and soil pollution.

[0005] Heavy oil in-situ recovery technology plays an important role in the development of heavy oil resources and can improve the recovery rate and mining effect. The specific technology selection needs to consider factors such as geological conditions, reservoir characteristics and economic feasibility.

[0006] Based on literature research, it was found that there is no relevant report on the device for continuous preparation of heavy oil thermal recovery additives through pipeline modification. Summary of the invention

[0007] In order to solve the above technical problems, an embodiment of the present invention provides a heavy oil thermal recovery steam injection device and a heavy oil thermal recovery method.

[0008] To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

[0009] The present invention provides a heavy oil thermal recovery steam injection device, comprising a high-temperature steam generator, a high-temperature steam pipeline, a delivery pump, a biomass liquefaction pipe and a biomass delivery pipe. The high-temperature steam generator is used to generate steam. The high-temperature steam pipeline is placed in a wellbore and is used to receive the steam generated by the high-temperature steam generator. The delivery pump is used to transport biomass. The biomass liquefaction pipe is placed in the high-temperature steam pipeline. The biomass delivery pipe is used to receive the biomass transported by the delivery pump and is located in the biomass liquefaction pipe.

[0010] In some embodiments, a heavy oil thermal recovery steam injection device further includes a first one-way valve, which is installed on a pipeline connecting the delivery pump and the biomass delivery pipe to allow biomass to flow into the biomass delivery pipe in a one-way manner.

[0011] In some embodiments, a heavy oil thermal recovery steam injection device further includes a second one-way valve, which is installed on a pipe connecting the high-temperature steam generator and the high-temperature steam pipe to allow steam to flow into the high-temperature steam pipe in one direction.

[0012] In some embodiments, a heavy oil thermal recovery steam injection device further includes a third one-way valve installed at the bottom of the biomass liquefaction pipe to allow steam to flow into the biomass liquefaction pipe in one direction.

[0013] The present invention also provides a heavy oil thermal recovery method based on a heavy oil thermal recovery steam injection device, comprising the following steps:

[0014] A. preparing biomass into slurry, conveying it to the biomass conveying pipe through a conveying pump and a first one-way valve, and conveying it to the biomass liquefaction pipe through the bottom of the biomass conveying pipe;

[0015] B. The steam generated by the high-temperature steam generator is transported to the high-temperature steam pipeline through the second one-way valve, and is transported to the biomass liquefaction pipe through the third one-way valve at the bottom of the biomass liquefaction pipe. The slurry in the biomass liquefaction pipe is reacted with the steam and the catalyst in the biomass liquefaction pipe to obtain bio-oil. The bio-oil flows upward with the steam, passes through the sieve holes at the top of the biomass liquefaction pipe with the steam, and then enters the oil layer.

[0016] In some embodiments, in step A, the particle size of the biomass is 100 nm-500 μm.

[0017] In some embodiments, in step B, the particle size of the catalyst is 0.5 μm-500 μm.

[0018] In some embodiments, in step B, the catalyst comprises a molecular sieve or a silica-supported catalyst.

[0019] In some embodiments, in step B, the temperature of the steam is 280-380°C.

[0020] The invention discloses a heavy oil thermal recovery steam injection device, which is a device for improving the efficiency of heavy oil recovery on the basis of steam throughput, and injecting mixed bio-oil and steam to improve the recovery efficiency; the device is arranged at the part below the wellhead, and only an injection pump and part of the transmission pipeline are added, thus saving the cost and space of building the device on the ground; in addition, the biomass comes from a wide range of sources, including not only wood, branches and sawdust from agricultural and forestry waste, but also corn stalks, wheat straw, sugarcane bagasse from agriculture, and distiller's grains, pulp and vegetable leaves from domestic waste.

[0021] The temperature required for biomass liquefaction is 280-380°C, which is completely provided by the steam generated by the high-temperature steam generator before injection into the formation, and the heat of the steam can be more reasonably utilized; the device of the present invention has a wide range of use, and can be used in offshore heavy oil thermal recovery, and can also be used in land high-temperature boiler injection; the device of the present invention is a dynamic reaction process during operation, and bio-oil is continuously generated during the reaction. The inorganic potassium salt, calcium salt and silicon dioxide released in the process are all natural catalysts; the device is a wellbore tool, and the injection well is partially modified, which will not affect the heavy oil recovery process.

[0022] The particle size of the catalyst can be adjusted. When a nanocatalyst is used, after catalytic hydrothermal liquefaction of biomass, the heavy oil can continue to be modified in situ as the bio-oil and steam enter the underground from the sieve holes at the top of the biomass liquefaction pipe. When a solid particle catalyst is used, the catalyst particle size is larger and can remain in the biomass liquefaction pipe to continuously catalyze the liquefaction reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a structural schematic diagram of a heavy oil thermal recovery steam injection device. DETAILED DESCRIPTION

[0024] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present disclosure.

[0025] In order to better understand the device of the present invention, the following is the preparation method of the device and the specific implementation process. It should be noted that the entire implementation method is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0026] Example

[0027] The present invention provides a heavy oil thermal recovery steam injection device, comprising a high-temperature steam generator 2, a high-temperature steam pipeline, a delivery pump 1, a biomass liquefaction pipe 4 and a biomass delivery pipe 6. The high-temperature steam generator 2 is used to generate steam. The high-temperature steam pipeline 5 is placed in a wellbore 3 and is used to receive the steam generated by the high-temperature steam generator 2. The delivery pump 1 is used to transport biomass. The biomass liquefaction pipe 4 is placed in the high-temperature steam pipeline 5. The biomass delivery pipe 6 is used to receive the biomass transported by the delivery pump 1 and is located in the biomass liquefaction pipe 4. By way of example, the high-temperature steam generator 2 can be a steam boiler.

[0028] In some embodiments, a heavy oil thermal recovery steam injection device further includes a first one-way valve, which is installed on a pipeline connecting the delivery pump 1 and the biomass delivery pipe 6 to allow the biomass to flow into the biomass delivery pipe in a one-way manner.

[0029] In some embodiments, a heavy oil thermal recovery steam injection device further includes a second one-way valve, which is installed on a pipe connecting the high-temperature steam generator 2 and the high-temperature steam pipeline 5 to allow steam to flow into the high-temperature steam pipeline 5 in one direction.

[0030] In some embodiments, a heavy oil thermal recovery steam injection device further includes a third one-way valve, which is installed at the bottom of the biomass liquefaction pipe 4 to allow steam to flow into the biomass liquefaction pipe 4 in one direction.

[0031] The heavy oil thermal recovery method using the above-mentioned heavy oil thermal recovery steam injection device specifically includes the following steps: the biomass can be selected from crop waste, forestry waste, processing waste and daily life waste, specifically, the forestry waste is scattered wood, branches, leaves and wood chips, wood and branches, sawdust, wood chips, tips in the processing process, fruit peels and fruit cores, agricultural waste such as corn stalks, sorghum stalks, wheat straw, rice straw, bean stalks and cotton stalks, rice husks, daily life waste such as wine lees, paper pulp, vegetable leaves, etc., and some livestock and poultry manure and other biomass. These biomasses are easy to transport and reduce production costs. The biomass is dried and mechanically crushed into small particles of 100nm-500μm, water is added to pre-treat it into a slurry state, and it is transported to the biomass transport pipe 6 through the transport 1. Since the pressure of the delivery pump 1 is greater than the pressure at the bottom of the biomass delivery pipe 6, the biomass enters the biomass liquefaction pipe 4 through the bottom of the biomass delivery pipe 6, which is filled with a solid catalyst (irregular catalyst with a particle size of 0.5μm-500μm, including molecular sieve catalyst, silica-loaded catalyst, etc.), and the steam generated by the steam boiler is discharged into the high-temperature steam pipe 5, and then the steam enters the biomass liquefaction pipe 4 through the third one-way valve at the bottom of the biomass liquefaction pipe 4. The steam reacts with the catalyst in the biomass liquefaction pipe 4 to liquefy the biomass, thereby liquefying the biomass. The ash obtained after liquefaction includes potassium, calcium, micron or even nanometer-level silica and bio-oil.

[0032] The pressure at the upper end of the biomass conveying pipe 6 is greater than the top pressure of the biomass liquefaction pipe 4, while the bottom pressure of the biomass liquefaction pipe 4 is greater than the top pressure of the biomass liquefaction pipe 4. Under the action of the pressure difference, the bio-oil and ash after the biomass liquefaction enter the biomass liquefaction pipe 4 and flow upward. At this time, the sieve hole at the top of the biomass liquefaction pipe 4 passes through the sieve hole diameter of 0.5μm-500μm together with the steam. Since the sieve hole diameter is 0.5μm-500μm, the catalyst particle size is 0.5μm-500μm. In order to allow the catalyst to participate in the liquefaction reaction in the biomass liquefaction pipe 4 and the catalyst does not enter the oil layer through the sieve hole, it is necessary to have a catalyst particle size larger than the aperture size of the sieve hole to meet the needs. The particle size and sieve hole diameter of the catalyst can be selected according to actual needs. In summary, the catalyst acts in the biomass liquefaction pipe 4, the steam and the bio-oil merge, and enter the oil layer together to achieve in-situ reforming.

[0033] After being liquefied at high temperature, biomass produces various small molecular compounds. For example, compounds containing methoxy groups and hydroxyl groups can play a good role in hydrogen supply. When entering the formation, they produce cracking reactions after contacting with heavy oil macromolecules. Due to the certain temperature of the injected steam and the oil layer itself, the heavy oil can be hydrothermally cracked in the oil layer. Moreover, after the bio-oil enters the second half of the production well, due to the decrease in temperature, other small molecules of bio-oil are liquefied and then dilute into the heavy oil, which can be diluted to a certain extent. And the modified wellbore device can be filled with catalysts to accelerate the liquefaction process. And because of the re-injection of underground modified heavy oil. When biomass enters the oil layer, due to the high efficiency of hydrogen supply of biomass liquefaction products, a small amount of steam can play a good modification role. The amount of biomass injected is generally 1 / 5-1 / 10 of the amount of steam. Bio-oil without modification can dilute heavy oil macromolecules and reduce the viscosity of heavy oil.

[0034] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0035] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A heavy oil thermal recovery steam injection device, characterized in that: include: A high temperature steam generator for generating steam; A high-temperature steam pipeline is placed in the wellbore and is used to receive the steam generated by the high-temperature steam generator; A delivery pump for delivering biomass; The biomass liquefaction pipe is placed in the high-temperature steam pipeline; A biomass delivery pipe, used for receiving the biomass delivered by the delivery pump and located in the biomass liquefaction pipe; A first one-way valve is installed on a pipeline connecting the delivery pump and the biomass delivery pipe to allow the biomass to flow into the biomass delivery pipe in one direction; A second one-way valve is installed on the pipe connecting the high-temperature steam generator and the high-temperature steam pipe to allow steam to flow into the high-temperature steam pipe in one direction; A third one-way valve is installed at the bottom of the biomass liquefaction pipe to allow steam to flow into the biomass liquefaction pipe in one direction; The heavy oil thermal recovery method of the heavy oil thermal recovery steam injection device comprises the following steps: A. preparing biomass into slurry, conveying it to the biomass conveying pipe through a conveying pump and a first one-way valve, and conveying it to the biomass liquefaction pipe through the bottom of the biomass conveying pipe; B. The steam generated by the high-temperature steam generator is transported to the high-temperature steam pipeline through the second one-way valve, and is transported to the biomass liquefaction pipe through the third one-way valve at the bottom of the biomass liquefaction pipe. The slurry in the biomass liquefaction pipe is reacted with the steam and the catalyst in the biomass liquefaction pipe to obtain bio-oil. The bio-oil flows upward with the steam, passes through the sieve holes at the top of the biomass liquefaction pipe with the steam, and then enters the oil layer.

2. A heavy oil thermal recovery steam injection device according to claim 1, characterized in that: In step A, the particle size of the biomass is 100 nm-500 μm.

3. A heavy oil thermal recovery steam injection device according to claim 1, characterized in that: In step B, the particle size of the catalyst is 0.5 μm-500 μm.

4. A heavy oil thermal recovery steam injection device according to claim 1, characterized in that: In step B, the catalyst comprises a molecular sieve or a silica-supported catalyst.

5. A heavy oil thermal recovery steam injection device according to claim 1, characterized in that: In step B, the temperature of the steam is 280-380°C.

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