System for reducing viscosity of thickened oil
By injecting non-coagulable gas and methanol solution into the heavy oil layer, the viscosity of the heavy oil is reduced, and the problems of high energy consumption and high carbon emissions during the heavy oil mining process are solved, thereby achieving a thick oil mining effect with lower energy consumption and low carbon emissions.
Patent Information
- Application Number
- CN202520154200.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-20
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2035-01-20
AI Technical Summary
The problems of high energy consumption and high carbon emissions during heavy oil mining.
The non-coagulable gas injection system and the methanol solution injection system are used to reduce the viscosity of the thick oil by injecting non-coagulable gas and methanol solution into the thick oil layer.
Without increasing carbon emissions, the viscosity of heavy oil is reduced, the permeability is improved, and energy consumption is reduced, and the problems of high energy consumption and high carbon emissions are solved during heavy oil mining.
Smart Images
Figure CN222863375U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of heavy oil exploitation, in particular to a system for reducing the viscosity of heavy oil. Background Art
[0002] Oil field exploitation includes onshore oil exploitation and underwater oil exploitation.
[0003] At present, most conventional oil fields are in the late stage of exploitation. With the reduction of conventional crude oil reserves, offshore oil field exploitation is gradually developing from shallow sea to deep sea, and from conventional crude oil to heavy oil. Deep sea heavy oil exploitation is becoming more and more important. Effective heavy oil exploitation technology is of great significance to the long-term dependence on imported oil.
[0004] Heavy oil is different from conventional crude oil. The content of light components in heavy oil is low, but the content of colloid and asphalt is high. The viscosity and density are much higher than those of ordinary crude oil. These properties determine that heavy oil has poor fluidity and is difficult to mine.
[0005] At present, when heavy oil reservoirs are mined, thin oil blending viscosity reduction technology, steam huff and puff, steam flooding, oil layer burning, thermochemical method and other mining methods are usually used. With the reduction of thin oil resources, thin oil blending viscosity reduction technology is difficult to meet the needs of heavy oil mining. Thermal viscosity reduction has serious heat loss after multiple rounds of thermal mining in the same oil reservoir. Steam huff and puff or steam flooding mining methods have high energy consumption and high carbon emissions, and some heavy oil wells are not suitable for steam huff and puff or steam flooding.
[0006] In the context of dual carbon emissions, heavy oil extraction needs to seek a low-energy, low-carbon emission method. Utility Model Content
[0007] The main purpose of the utility model is to provide a system for reducing the viscosity of heavy oil, aiming to solve the problems of high energy consumption and high carbon emission in the heavy oil production process.
[0008] In order to achieve the above-mentioned purpose, the system for reducing the viscosity of heavy oil proposed in the utility model comprises a non-condensable gas injection system and a methanol solution injection system;
[0009] The non-condensable gas injection system comprises a gas inlet for inputting non-condensable gas, and the non-condensable gas injection system further comprises a gas outlet for injecting non-condensable gas into the oil well casing, so as to inject non-condensable gas into the heavy oil layer through the oil well casing;
[0010] The methanol solution injection system comprises a solution inlet for inputting methanol solution, and the methanol solution injection system also comprises a solution outlet for injecting methanol solution into the oil well casing, so as to inject methanol solution into the heavy oil layer through the oil well casing.
[0011] Optionally, the non-condensable gas injection system includes a compressor, a gas storage device and a first regulating valve which are connected in sequence, the gas inlet is connected to the compressor; and the opening of the gas outlet is adjusted by the first regulating valve.
[0012] Optionally, the methanol solution injection system comprises a booster pump, a solution storage device and a second regulating valve which are connected in sequence; the solution inlet is connected to the booster pump, and the solution outlet is adjusted in opening by the second regulating valve.
[0013] Optionally, a first pressure detection unit is provided between the compressor and the gas storage device, and a first temperature detection unit is provided for the gas storage device; and a first flow meter is provided between the gas storage device and the gas outlet.
[0014] Optionally, a first safety pressure relief unit and / or a first program-controlled valve is further provided between the gas storage device and the gas outlet.
[0015] Optionally, a second pressure detection unit is provided between the booster pump and the solution storage device, and a second temperature detection unit is provided for the solution storage device; and a second flow meter is provided between the solution storage device and the solution outlet.
[0016] Optionally, a second safety pressure relief unit and / or a second program-controlled valve is further provided between the solution storage device and the solution outlet.
[0017] Optionally, the gas storage device is a gas storage tank; and / or the solution storage device is a solution storage tank.
[0018] Optionally, the system for reducing the viscosity of heavy oil also includes an intermediate storage tank for recovering methanol released from the mined crude oil, the intermediate storage tank being used to contain water so that the methanol input into the intermediate storage tank is dissolved into the water in the intermediate storage tank to form a methanol solution; the intermediate storage tank is used to communicate with the solution inlet.
[0019] Optionally, the non-condensable gas is CO 2 、N 2 , CO, flue gas and exhaust gas.
[0020] In the technical scheme of the utility model, non-condensable gas is injected into the oil well casing, thereby injecting into the heavy oil layer. After the injection, the well is shut down for a period of time, so that the gas diffuses inside the heavy oil for a period of time, reduces the viscosity of the heavy oil, reduces the surface tension of the heavy oil, and improves the overall permeability. Without increasing carbon emissions, the viscosity of the heavy oil can be reduced to a certain extent. Injecting methanol solution into the heavy oil layer, and shutting down the well for a period of time after the injection, the viscosity of the heavy oil can also be reduced; the injected methanol is used as a fuel. After being mined out of the well with the crude oil, as the pressure decreases, the methanol with a lower boiling point is released first, and after recovery, it can be returned to the oil production system or sold as a refining by-product. Therefore, the energy consumption and carbon emissions of the method of injecting methanol solution to reduce the viscosity of heavy oil are also lower than those of the existing method. This injection method can reduce surface tension, improve mobility ratio, and reduce the viscosity of heavy oil. Therefore, the technical scheme of the utility model is conducive to solving the problems of high energy consumption and high carbon emissions in the process of heavy oil mining. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.
[0022] Figure 1 It is a schematic diagram of a system for reducing the viscosity of heavy oil in the utility model;
[0023] Figure 2 It is a schematic diagram of the non-condensable gas injection system in the utility model;
[0024] Figure 3 It is a schematic diagram of the methanol solution injection system in the present invention.
[0025] Description of Figure Numbers:
[0026] 101-compressor; 102-gas storage device; 103-heavy oil layer; 104-first pressure detection unit; 105-first flow meter; 106-first regulating valve; 107-first temperature detection unit; 108-first safety pressure relief unit; 109-oil well casing; 110-first program-controlled valve;
[0027] 201 - compression pump; 202 - solution storage device; 204 - second pressure detection unit; 205 - second flow meter; 206 - second regulating valve; 207 - second temperature detection unit; 208 - second safety pressure relief unit; 210 - second program-controlled valve.
[0028] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION
[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0030] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.
[0031] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0032] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0033] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.
[0034] The utility model provides a system for reducing the viscosity of heavy oil.
[0035] Please refer to Figures 1 to 3, in order to achieve the above-mentioned purpose, the system for reducing the viscosity of heavy oil proposed by the utility model includes a non-condensable gas injection system and a methanol solution injection system;
[0036] The non-condensable gas injection system includes a gas inlet for inputting non-condensable gas, and the non-condensable gas injection system also includes a gas outlet for injecting non-condensable gas into the oil well casing 109, so as to inject non-condensable gas into the heavy oil layer 103 through the oil well casing 109;
[0037] The methanol solution injection system includes a solution inlet for inputting methanol solution, and the methanol solution injection system also includes a solution outlet for injecting methanol solution into the oil well casing 109 , so as to inject methanol solution into the heavy oil layer 103 through the oil well casing 109 .
[0038] In the technical solution of the utility model, non-condensable gas is injected into the oil well casing 109, and then injected into the heavy oil layer 103. After the injection, the well is shut down for a period of time, so that the gas diffuses inside the heavy oil for a period of time, the viscosity of the heavy oil is reduced, the surface tension of the heavy oil is reduced, and the overall permeability is improved. Without increasing carbon emissions, the viscosity of the heavy oil can be reduced to a certain extent. Injecting methanol solution into the heavy oil layer 103, and shutting down the well for a period of time after the injection, the viscosity of the heavy oil can also be reduced; the injected methanol is used as a fuel. After being mined out of the well with the crude oil, as the pressure decreases, the methanol with a lower boiling point is released first, and after recovery, it can be returned to the oil production system or sold as a refining by-product. Therefore, the energy consumption and carbon emissions of the method of injecting methanol solution to reduce the viscosity of heavy oil are also lower than those of the existing method. This injection method can reduce surface tension, improve mobility ratio, and reduce the viscosity of heavy oil. Therefore, the technical solution of the utility model is conducive to solving the problems of high energy consumption and high carbon emissions in the process of heavy oil mining.
[0039] my country's oil fields are generally in the third heavy oil production stage. The heavy oil has high colloid and asphaltene content. At the oil layer temperature, the ground degassing viscosity is above 100mPa.s, which makes it difficult to produce. In order to further improve the production rate, certain methods need to be used to effectively reduce the viscosity of heavy oil.
[0040] Non-condensable gas refers to gas that cannot be converted into liquid by compression or cooling under certain pressure and temperature conditions. The heavy oil refers to heavy crude oil buried 350m to 2500m below the ground or deep sea with a viscosity of 100mPa.s to 15000mPa.s.
[0041] The methanol solution can be an aqueous solution of methanol, which has low cost. Of course, the solvent in the methanol solution can also be other available types. The volume concentration of the methanol solution is 20% to 90%. The pressure of the methanol solution injected into the oil well casing 109 is greater than the pressure value at the bottom of the oil layer. Specifically, the pressure of the methanol solution can be 3.5MPa to 25MPa, and the temperature of the methanol solution can be 120°C to 238°C.
[0042] Specifically, the steps of injecting the methanol solution and injecting the non-condensable gas may be switched in order.
[0043] The utility model provides two viscosity reducing substances: non-condensable gas and methanol coupling. These two substances are simple in composition, common and easy to obtain, have mature preparation technology, and are relatively cheap. After methanol is dissolved in the oil layer, it can be recovered after being mined simultaneously with crude oil. This method is suitable for heavy oil mining scenarios.
[0044] Injecting non-condensable gas into heavy oil can reduce the viscosity of heavy oil through gas drive.
[0045] The hydroxyl group (-OH) in the methanol molecule has a strong polarity and can form hydrogen bonds with water molecules. This hydrogen bonding helps to destroy the interaction between the original solvent molecules, thereby reducing the viscosity of the solution. At the same time, methanol, as a solvent, can reduce the interaction between solute molecules, making it easier for solute molecules to move in the solvent. This solvent effect helps to reduce the viscosity of the solution and improve the flow performance.
[0046] Optionally, the non-condensable gas injection system includes a compressor 101 , a gas storage device 102 and a first regulating valve 106 which are connected in sequence, the gas inlet is connected to the compressor 101 ; and the opening of the gas outlet is adjusted by the first regulating valve 106 .
[0047] Specifically, the non-condensable gas is pressurized to a specified pressure by the compressor 101 and then stored in the gas storage device 102 . The non-condensable gas is quantitatively injected into the heavy oil layer 103 through the first regulating valve 106 , and the well is shut down for a period of time.
[0048] The inlet of the compressor 101 is connected to an external gas delivery pipeline, the outlet of the compressor 101 is connected to the inlet of the gas storage device 102 through a pipeline, and the outlet of the gas storage device 102 is connected to the injection well through a pipeline.
[0049] Optionally, the methanol solution injection system includes a booster pump, a solution storage device 202 and a second regulating valve 206 which are connected in sequence; the solution inlet is connected to the booster pump, and the solution outlet is adjusted in opening by the second regulating valve 206 .
[0050] Specifically, methanol is pressurized to a specified pressure by a booster pump and then stored in the solution storage device 202 , and the methanol solution is quantitatively injected into the heavy oil layer 103 through the second regulating valve 206 .
[0051] The inlet of the booster pump is connected to an external methanol solution delivery pipeline, the outlet of the booster pump is connected to the inlet of the solution storage component through a pipeline, and the outlet of the solution storage component is connected to the injection well through a pipeline.
[0052] Optionally, a first pressure detection unit 104 is provided between the compressor 101 and the gas storage device 102, and a first temperature detection unit 107 is provided on the gas storage device 102; and a first flow meter 105 is provided between the gas storage device 102 and the gas outlet.
[0053] Optionally, a first safety pressure relief unit 108 and / or a first program-controlled valve 110 is further provided between the gas storage device 102 and the gas outlet.
[0054] Specifically, a remote pressure gauge is installed on the pipeline between the compressor 101 outlet and the gas storage device 102 inlet, a remote thermometer is installed on the main body of the gas storage device 102, and a regulating valve, a program-controlled valve and a flow meter are installed on the outlet pipeline of the gas storage device 102.
[0055] Optionally, a second pressure detection unit 204 is provided between the booster pump and the solution storage device 202, and a second temperature detection unit 207 is provided on the solution storage device 202; and a second flow meter 205 is provided between the solution storage device 202 and the solution outlet.
[0056] Optionally, a second safety pressure relief unit 208 and / or a second program-controlled valve 210 is further provided between the solution storage device 202 and the solution outlet.
[0057] A remote pressure gauge is installed on the booster pump outlet and the solution storage device 202 inlet pipeline, a remote thermometer is installed on the solution storage device 202 body, and a regulating valve, a program-controlled valve and a flow meter are installed on the outlet pipeline of the solution storage device 202.
[0058] Furthermore, the first safety pressure relief unit 108 and the second safety pressure relief unit 208 may be safety valves respectively.
[0059] Optionally, the gas storage device 102 is a gas storage tank; and / or the solution storage device 202 is a solution storage tank.
[0060] Optionally, the system for reducing the viscosity of heavy oil also includes an intermediate storage tank for recovering methanol released from the mined crude oil, the intermediate storage tank being used to contain water so that the methanol input into the intermediate storage tank is dissolved into the water in the intermediate storage tank to form a methanol solution; the intermediate storage tank is used to communicate with the solution inlet.
[0061] The methanol solution injected into the oil well casing 109 is also used as a fuel. After being extracted from the well together with the crude oil, as the pressure decreases, the methanol with a lower boiling point is released first. After recovery, it can be returned to the oil production system or sold as a refining by-product.
[0062] Optionally, the non-condensable gas is CO 2 、N 2 , CO, flue gas and exhaust gas. Specifically, the non-condensable gas in the present invention is preferably CO 2 , the purity of non-condensable gas can be 50% to 99%.
[0063] Specifically, non-condensable gases (such as CO 2 ) The injection volume Q is determined by the oil layer thickness σ, the equivalent radius r of the oil layer to be produced, and the average porosity of the oil layer. And the volume ratio p of the injected non-condensable gas to the pores of heavy oil hydrocarbons is determined by:
[0064]
[0065] Where Q is the amount of non-condensable gas injected, in m 3 ; σ is the thickness of the oil layer to be produced, in m; r is the equivalent radius of the oil layer to be produced, in m; is the average porosity of the oil layer to be produced, in %, and p is the volume ratio of the injected non-condensable gas to the pores of heavy oil hydrocarbons.
[0066] The above volume ratio may be 0.2 to 0.8, preferably, the volume ratio is 0.2 to 0.5.
[0067] Furthermore, CO 2 The single diffusion time is 15h to 180h depending on the different conditions of the oil field.
[0068] The methanol injection volume W is determined by the mass of the heavy oil and the methanol-heavy oil mass ratio, and the relationship between them is:
[0069]
[0070] Where W is the amount of methanol (100% methanol) injected, in m 3 ; b is the mass ratio of methanol to heavy oil, ρ is the density of heavy oil, unit is kg / m 3 .
[0071] Specifically, the methanol solution in the utility model can be a methanol-water solution, and the methanol injection amount (excluding water): the mass ratio of the heavy oil to be produced is 1:20 to 1:60. Furthermore, the methanol injection amount (excluding water): the mass ratio of the heavy oil to be produced is preferably 1:28 to 1:45.
[0072] CO 2 It comes from industrial waste gas capture, biomass combustion, air capture, etc. and is renewable.
[0073] As a preferred option, methanol is derived from CO 2 Add H 2 Synthesis, H 2 The methanol produced by photovoltaic electrolysis of water is green methanol.
[0074] The methanol in the utility model is produced by combining green hydrogen and renewable CO 2 Synthesized as green methanol.
[0075] Preferably, the methanol solution is obtained by the following method: injecting methanol into an intermediate tank filled with a certain amount of water to dissolve the methanol in the water to obtain the methanol aqueous solution.
[0076] Compared with the prior art, the present invention has the following beneficial effects:
[0077] 1. The methanol solution used in this scheme is made of renewable CO 2 (Industrial waste gas capture, biomass combustion, air capture, etc.) and green hydrogen (hydrogen produced by wind power or photovoltaic water electrolysis) are synthesized into green methanol. The cost of the entire production chain is low, zero carbon emissions can be achieved, and the social benefits are significant;
[0078] 2. This scheme uses renewable CO 2 The first step is to reduce the viscosity of heavy oil, reduce the surface tension of heavy oil, and improve the overall permeability. Without increasing carbon emissions, the viscosity of heavy oil can be reduced to a certain extent;
[0079] 3. The injected methanol solution is also used as a fuel. After it is extracted from the well along with the crude oil, as the pressure decreases, the methanol with a lower boiling point is released first. After recovery, it can be returned to the oil production system or sold as a refining by-product.
[0080] In a specific embodiment, in order to achieve the above purpose, the utility model patent adopts a two-step chemical flooding mining method, and the specific steps are as follows:
[0081] S1: Start the compressor 101 to transfer the CO 2 After being pressurized, it is stored in the gas storage device 102. When gas needs to be injected, the first program-controlled valve 110 is opened, and CO 2The high-pressure gas is quantitatively delivered to the oil well casing 109 through the pipeline. After the accumulated amount of the first flow meter 105 reaches a given amount, the first program-controlled valve 110 is closed.
[0082] S2: Start the booster pump 201 to pressurize the delivered methanol solution and store it in the solution storage device 202. When the methanol solution needs to be injected, the second program-controlled valve 210 is opened, and the methanol solution is quantitatively delivered to the oil well casing 109 through the pipeline. After the accumulated amount of the second flow meter 205 reaches a given amount, the second program-controlled valve 210 is closed.
[0083] Embodiment 1:
[0084] For the heavy oil from an oil field in the east, the viscosity is 2050mPa.s, the pressure is 11MPa, the porosity is 28%, the specific gravity is 0.94, and the weight of the heavy oil in a single experiment is 50kg. According to the first step S1 of the method, the compressor 101 is started to convert CO 2 The gas is pressurized to 12 MPa and 102°C, transported through pipelines, and stored in gas storage equipment 102. When injection is required, the first programmable valve 110 is opened, and CO 2 The heavy oil is injected through the injection pipe at the radius center of the heavy oil equipment, and the injection pipe is 200 mm from the bottom. After the injected volume reaches a given amount, the first program-controlled valve 110 is closed, and the viscosity of the heavy oil is measured after it is sealed for 24 hours.
[0085] In this embodiment, CO 2 The purity is 95% (the remaining components can be N 2 and CO), injecting CO 2 The volume ratio is 0.1.
[0086] Embodiment 2:
[0087] As described in Example 1, CO 2 The methods for reducing the viscosity of heavy oil are different in that:
[0088] In this example, CO is injected 2 The volume ratio is 0.2.
[0089] Embodiment 3:
[0090] As described in Example 1, CO 2 The methods for reducing the viscosity of heavy oil are different in that:
[0091] In this example, CO is injected 2 The volume ratio is 0.3.
[0092] Embodiment 4:
[0093] As described in Example 1, CO 2 The methods for reducing the viscosity of heavy oil are different in that:
[0094] In this example, CO is injected 2 The volume ratio is 0.5.
[0095] Embodiment 5:
[0096] As described in Example 1, CO 2 The methods for reducing the viscosity of heavy oil are different in that:
[0097] In this example, CO is injected 2 The volume ratio is 0.7.
[0098] Table 1 shows the different CO 2 Viscosity measurement results of heavy oil in the case of volume ratio:
[0099] Table 1:
[0100] name Example 1 Example 2 Example 3 Example 4 Example 5 Viscosity, mPa.S 1763 1517 1086 1045 1011
[0101] As shown in Table 1, the injection of CO 2 The viscosity of the heavy oil decreased slightly. 2 As the volume ratio increases, the viscosity of heavy oil further decreases. However, when the volume ratio is greater than 0.5, the viscosity reduction rate decreases significantly, and the corresponding volume ratio has poor economic benefits.
[0102] Embodiment 6:
[0103] In the first step of this embodiment, CO 2 The methods for reducing the viscosity of heavy oil are different in that:
[0104] This example uses CO 2 In combination with the method for reducing the viscosity of heavy oil by using methanol, after the first step S1, according to the second step S2 of the method of the present invention, the booster pump 201 is started to pressurize the methanol to 12 MPa, and the methanol is transported through a pipeline and stored in a solution storage device 202. When methanol needs to be injected, the second program-controlled valve 210 is opened, and the methanol is injected through the injection pipe at the radial center of the heavy oil equipment, and the injection pipe is 200 mm from the bottom. After the injection amount reaches a given amount, the second program-controlled valve 210 is closed, and the viscosity of the heavy oil is measured after it is sealed for 48 hours.
[0105] In this embodiment, the methanol:heavy oil mass ratio is 1:30, and the methanol temperature is controlled at 50°C.
[0106] Embodiment 7:
[0107] As described in Example 6, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0108] In this embodiment, the methanol temperature is controlled at 80°C.
[0109] Embodiment 8:
[0110] As described in Example 6, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0111] In this embodiment, the methanol temperature is controlled at 120°C.
[0112] Embodiment 9:
[0113] As described in Example 6, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0114] In this embodiment, the methanol temperature is controlled at 150°C.
[0115] Embodiment 10:
[0116] As described in Example 6, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0117] In this embodiment, the methanol temperature is controlled at 180°C.
[0118] Embodiment 11:
[0119] As described in Example 6, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0120] In this embodiment, the methanol temperature is controlled at 200°C.
[0121] Embodiment 12:
[0122] As described in Example 6, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0123] In this embodiment, the methanol temperature is controlled at 230°C.
[0124] Embodiment 13:
[0125] As described in Example 9, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0126] In this embodiment, the mass ratio of methanol to heavy oil is 1:20.
[0127] Embodiment 14:
[0128] As described in Example 9, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0129] In this embodiment, the mass ratio of methanol to heavy oil is 1:40.
[0130] Embodiment 15:
[0131] As described in Example 9, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0132] In this embodiment, the mass ratio of methanol to heavy oil is 1:50.
[0133] Embodiment 16:
[0134] As described in Example 9, CO 2 The method of combining methanol to reduce the viscosity of heavy oil is different in that:
[0135] In this embodiment, the mass ratio of methanol to heavy oil is 1:60.
[0136] Table 2 shows the results of heavy oil viscosity measurement at different methanol temperatures and different mass ratios:
[0137] Table 2:
[0138]
[0139]
[0140] As shown in Table 2, the injection of CO 2 After injecting methanol, the viscosity of the heavy oil is further reduced, with the highest viscosity reduction rate reaching 90%.
[0141] The above are only preferred embodiments of the present invention, and do not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.
Claims
1. A system for reducing the viscosity of heavy oil, characterized in that: Including non-condensable gas injection system and methanol solution injection system; The non-condensable gas injection system comprises a gas inlet for inputting non-condensable gas, and the non-condensable gas injection system further comprises a gas outlet for injecting non-condensable gas into the oil well casing, so as to inject non-condensable gas into the heavy oil layer through the oil well casing; The methanol solution injection system comprises a solution inlet for inputting methanol solution, and the methanol solution injection system also comprises a solution outlet for injecting methanol solution into the oil well casing, so as to inject methanol solution into the heavy oil layer through the oil well casing.
2. The system for reducing the viscosity of heavy oil according to claim 1, characterized in that: The non-condensable gas injection system comprises a compressor, a gas storage device and a first regulating valve which are connected in sequence, the gas inlet is connected to the compressor; the gas outlet is opened by adjusting the first regulating valve.
3. The system for reducing the viscosity of heavy oil according to claim 2, characterized in that: The methanol solution injection system comprises a booster pump, a solution storage device and a second regulating valve which are connected in sequence; the solution inlet is connected to the booster pump, and the solution outlet is adjusted in opening by the second regulating valve.
4. The system for reducing the viscosity of heavy oil according to claim 2, characterized in that: A first pressure detection unit is arranged between the compressor and the gas storage device, and a first temperature detection unit is arranged on the gas storage device; and a first flow meter is arranged between the gas storage device and the gas outlet.
5. The system for reducing the viscosity of heavy oil according to claim 4, characterized in that: A first safety pressure relief unit and / or a first program-controlled valve are also arranged between the gas storage device and the gas outlet.
6. The system for reducing the viscosity of heavy oil according to claim 3, characterized in that: A second pressure detection unit is arranged between the booster pump and the solution storage device, and a second temperature detection unit is arranged on the solution storage device; and a second flow meter is arranged between the solution storage device and the solution outlet.
7. The system for reducing the viscosity of heavy oil according to claim 4, characterized in that: A second safety pressure relief unit and / or a second program-controlled valve is also provided between the solution storage device and the solution outlet.
8. The system for reducing the viscosity of heavy oil according to claim 3, characterized in that: The gas storage device is a gas storage tank; and / or the solution storage device is a solution storage tank.
9. The system for reducing the viscosity of heavy oil according to claim 1, characterized in that: The system for reducing the viscosity of heavy oil also includes an intermediate storage tank for recovering methanol released from the mined crude oil, the intermediate storage tank is used to contain water so that the methanol input into the intermediate storage tank is dissolved in the water in the intermediate storage tank to form a methanol solution; the intermediate storage tank is used to communicate with the solution inlet.
10. The system for reducing the viscosity of heavy oil according to any one of claims 1 to 9, characterized in that: The non-condensable gas is any one of CO2, N2, CO, flue gas and exhaust gas.