Ultra-heavy oil low-carbon cyclic mining method and system

Abstract

The invention provides a method and system for achieving ultra-heavy oil low-carbon cycle exploitation, and relates to the technical field of oil exploitation. According to the method, clean energy is utilized for power generation, and then the obtained electric energy is used for super-heavy oil layer exploitation and electrolytic hydrogen production. The produced super-heavy oil is modified by using hydrogen produced by electrolysis, and a light hydrocarbon solvent and light oil are produced and separated. And then the light hydrocarbon solvent replaces steam and is injected into the oil layer again for exploitation. And the mined super heavy oil is modified. In addition, the electric energy and the hydrogen energy are stored by the energy storage equipment, and power is provided when needed. The method also adopts a crude oil treatment device to recover the light hydrocarbon solvent, and an intelligent control system performs whole-process monitoring. In the whole process, super-heavy oil circulation recovery driven by clean energy is achieved. Compared with the prior art, the method utilizes clean energy to efficiently exploit super-heavy oil, and meanwhile, energy consumption and carbon emission are greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of petroleum exploitation, and in particular to a method and system for low-carbon cyclic exploitation of super-heavy oil. Background Art

[0002] The global reserves of extra-heavy oil are huge, and it is the raw material for many chemical products that cannot be replaced by fossil energy. However, at present, the exploitation of extra-heavy oil has the following problems:

[0003] First, the mining is difficult, the energy consumption and emissions generated per unit of recovery are high, and the viscosity of super-heavy crude oil is greater than 50,000 centipoise and the density of crude oil is greater than 0.95g / cm 3 First, the traditional extraction method of steam injection can only achieve a low recovery rate, and the unit carbon emission reaches more than 1.8 tons of carbon / ton of oil; second, the ultra-heavy oil extracted is of poor quality and has an obvious price disadvantage. The sales price of ultra-heavy oil products is 400-1000 yuan / ton lower than that of light crude oil, and it is always at the lowest end of the value chain.

[0004] One existing solution is to use clean energy such as wind and solar energy to extract super-heavy oil to achieve energy conservation and emission reduction, but clean energy is highly volatile and cannot be directly and stably used in oil field extraction, which will affect extraction efficiency. Clean energy is difficult to combine with oil field extraction technology. Summary of the invention

[0005] The purpose of the present invention is to propose a method and system for realizing low-carbon cyclic exploitation of ultra-heavy oil in view of the problems of high energy consumption, high carbon dioxide emission and poor oil quality in the existing steam injection development of ultra-heavy oil reservoirs, so as to make full use of clean energy in the oilfield exploitation process, improve the oil quality of ultra-heavy oil, improve the recovery rate of ultra-heavy oil reservoirs and reduce carbon emissions.

[0006] To achieve the above object, the present invention is implemented through the following technical solutions:

[0007] A low-carbon cycle production method for ultra-heavy oil comprises the following steps:

[0008] S1: Power generation: using wind and / or solar energy to generate electricity;

[0009] S2: Oil recovery: Inject steam into the oil layer to recover extra-heavy oil resources;

[0010] S3: Hydrogen production: using the electricity generated in S1 to produce hydrogen by electrolysis;

[0011] S4: Upgrading: Using the hydrogen produced in S3 to upgrade the super heavy oil produced in S2, obtain and separate light hydrocarbon solvent and light oil;

[0012] S5: Harvest light oil; inject the light hydrocarbon solvent separated in S4 into the oil layer instead of the steam in S2 to exploit the super heavy oil resources.

[0013] Furthermore: S1 also includes storing the obtained electric energy using an electric storage device.

[0014] Going one step further: using the stored electrical energy for extra-heavy oil production operations in S2.

[0015] Furthermore: S3 also includes compressing and storing the produced hydrogen using a hydrogen storage device.

[0016] Furthermore, after S5, the process further includes: recovering the light hydrocarbon solvent in the produced extra heavy oil resources, and re-investing the recovered light hydrocarbon solvent in S2 to inject it into the oil layer for producing extra heavy oil.

[0017] Furthermore: the process of S1-S5 is controlled by an intelligent control system.

[0018] The present invention also provides a system for a low-carbon cycle development method for ultra-heavy oil, comprising a clean energy power generation system, a hydrogen production system, a mining system, and a reforming and separation system, wherein the clean energy power generation system is electrically connected to the hydrogen production system and the mining system, and the reforming and separation system is connected between the hydrogen production system and the mining system, wherein the outlet of the reforming and separation system is connected to the inlet of the mining system, the outlet of the mining system is connected to the inlet of the reforming and separation system, and a crude oil processing device is connected between the outlet of the mining system and the inlet of the separation system.

[0019] Furthermore, a backup power grid is also included, and the hydrogen production system is also connected to the backup power grid to maintain the continuity of hydrogen production by electrolysis.

[0020] Furthermore: it also includes an intelligent control system, which is connected to the clean energy power generation system, hydrogen production system, mining system, and reforming and separation system by electrical signals.

[0021] Furthermore: a solvent recovery device is connected between the crude oil processing device and the outlet of the production system, and the solvent recovery device is also connected to the inlet of the production system.

[0022] Compared with the original technology, the present invention has the following beneficial effects:

[0023] 1. Clean energy power generation can be used in super-heavy oil production and also for hydrogen production. After converting electrical energy into hydrogen energy, it can be converted into hydrogen energy that can be stably stored and used for super-heavy oil upgrading to improve oil quality. This effectively combines clean energy with super-heavy oil production projects and reduces carbon emissions.

[0024] 2. After ultra-heavy oil is modified, light hydrocarbon solvents are produced, which can replace steam and be introduced into the oil layer for mining operations. The oil recovery efficiency of light hydrocarbon solvents is higher than that of steam, which greatly reduces the amount of steam used, reduces the consumption of fossil energy, and improves the recovery rate of mining operations.

[0025] 3. Recover the light hydrocarbon solvents in the produced super-heavy oil fluid, recycle them and save resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the structure of a low-carbon cycle production system for ultra-heavy oil;

[0027] Figure 2 It is the working flow chart of the intelligent control system;

[0028] In the figure:

[0029] 1. Backup power grid; 2. Clean energy power generation system; 3. Hydrogen production system; 4. Mining system; 5. Reforming and separation system; 6. Intelligent control system; 7. Crude oil processing unit; 8. Solvent recovery unit; 9. Light oil harvesting unit. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0032] A low-carbon cycle production method for ultra-heavy oil comprises the following steps:

[0033] S1: Power generation: Use wind energy and / or solar energy to generate electricity, and use power storage equipment to store the resulting electricity;

[0034] S2: Oil production: Steam is injected into the oil layer to produce extra-heavy oil resources, and the electrical energy stored in S1 is used for extra-heavy oil production operations;

[0035] S3: Hydrogen production: The electricity generated in S1 is used for electrolysis to produce hydrogen, and the produced hydrogen is compressed and stored using hydrogen storage equipment;

[0036] S4: Upgrading: Using the hydrogen produced in S3 to upgrade the super heavy oil produced in S2, obtain and separate light hydrocarbon solvent and light oil;

[0037] S5: harvesting light oil; injecting the light hydrocarbon solvent separated in S4 into the oil layer instead of the steam in S2 to exploit the super-heavy oil resources;

[0038] S6: Recover the light hydrocarbon solvent in the extra heavy oil resources produced in S5, and re-invest the recovered light hydrocarbon solvent in S2 and inject it into the oil layer for extra heavy oil production.

[0039] The process of S1-S6 is controlled by the intelligent control system 6.

[0040] The present invention also provides a system for a low-carbon cycle development method for ultra-heavy oil, comprising a clean energy power generation system 2, a hydrogen production system 3, a mining system 4, a reforming and separation system 5, a backup power grid 1 and an intelligent control system 6; the clean energy power generation system 2 is electrically connected to the hydrogen production system 3 and the mining system 4, the reforming and separation system 5 is connected between the hydrogen production system 3 and the mining system 4, wherein the outlet of the reforming and separation system 5 is connected to the inlet of the mining system 4, and the outlet of the mining system 4 is connected to the inlet of the reforming and separation system 5; the outlet of the reforming and separation system 5 is also connected to a light oil harvesting device 9; a crude oil processing device 7 is connected between the outlet of the mining system 4 and the inlet of the separation system, a solvent recovery device 8 is connected between the crude oil processing device 7 and the outlet of the mining system 4, and the solvent recovery device 8 is also connected to the inlet of the mining system 4.

[0041] The hydrogen production system 3 is also connected to a backup power grid 1 to maintain the continuity of hydrogen production by electrolysis. The hydrogen production system 3 by electrolysis is usually coupled with other equipment and control systems, such as water treatment equipment, gas treatment equipment, and automatic control systems. These equipment and systems may have certain requirements for the power supply stability of the hydrogen production system 3 by electrolysis to ensure the coordinated operation of the entire system. Unstable power supply may cause failure or performance degradation of other equipment, thereby affecting the efficiency and reliability of the entire system.

[0042] The intelligent control system 6 is electrically connected to the clean energy power generation system 2, the hydrogen production system 3, the mining system 4, and the reforming and separation system 5. The intelligent control system 6 includes four modules: a data monitoring module, a production data collection module, a big data AI analysis module, and a production parameter intelligent control module.

[0043] Among them, the data monitoring module is used to monitor the production status of each subsystem and provide real-time production warning;

[0044] The production data collection module is used to collect power generation data, hydrogen production rate, light hydrocarbon production rate, hydrogen consumption rate, super heavy oil production data, and light hydrocarbon recovery rate in real time;

[0045] The big data AI analysis module is used to formulate the best matching parameters for the backup power grid 1, hydrogen production, reforming, separation, oil production and other systems based on the data collected by the above-mentioned production data collection module;

[0046] The production parameter intelligent control module is used to adjust the production of each system according to the parameters calculated by the above-mentioned big data AI analysis module.

[0047] The advantages of the present invention are described below by some embodiments:

[0048] Example 1

[0049] A clean energy power generation and storage system of 1.2 square kilometers will be built, with an annual production time of 300 days and an annual power generation of 75 million kWh. The reforming and separation system 5 will hydrogenate and reform 100 tons of crude oil every day and process 30,000 tons of extra-heavy oil annually. The extra-heavy oil will be reformed at a hydrogenation ratio of 3% (mass). Through the optimization of the intelligent control system 6, it will ensure that the hydrogen production system 3 can stably produce 3 tons of hydrogen every day and 900 tons of green hydrogen annually.

[0050] According to the existing hydrogen production process level of electrolysis of alkaline water, 1.0Nm 3 Hydrogen consumes an average of 5 kWh of electricity. The intelligent control system 6 implements real-time intelligent scheduling, clean energy power generation and storage system, and backup power grid 1 automatically switch according to seasonal changes in light intensity and duration, changes in day and night, or changes in wind speed. 50 million kWh of green electricity is consumed locally throughout the year, and the remaining 25 million kWh of electricity is used for oil field production and operation, reducing the scale of thermal power generation.

[0051] The reforming and separation system 5 produces 10 tons of light hydrocarbon solvents per day, and produces 3,000 tons of light hydrocarbon solvents, 27,300 tons of light oil, and 600 tons of residual oil per year. The 10 tons of light hydrocarbon solvents produced per day can be injected into one well group to carry out solvent-assisted SAGD to produce heavy oil.

[0052] The intelligent control system 6 monitors and warns of security risks of the connected system in real time, automatically identifies and judges abnormal parameters, intelligently matches the optimal operating parameters, reduces energy consumption, and realizes green and low-carbon operation.

[0053] The newly mined extra-heavy oil is transported to the crude oil processing equipment and undergoes processes such as dehydration, desalting, and impurity removal before entering the upgrading and separation system 5 as a raw material to continue producing light hydrocarbon solvents and light oil. The light hydrocarbon solvent is injected into the mining system 4 for the green and low-carbon mining of heavy oil. The 27,300 tons of light oil produced annually is directly sold to the sales system. When the international oil price is US$100 per barrel, the price of light oil is RMB 800 per ton higher than that of heavy oil, and the direct sales revenue increases by RMB 21.84 million per year.

[0054] Light hydrocarbon injection production system 4 can reduce steam consumption by 10,800 tons and reduce 720,000 Nm per year 3Natural gas consumption is equivalent to reducing CO2 emissions by 1,360 tons. The market price of steam is 100 yuan / ton, saving 1.08 million yuan in steam costs each year. The estimated recovery rate of 41 SAGD well groups in the mining system will increase from 45% to 60% over the entire life cycle, which can increase crude oil production by 37,500 tons and directly generate 188 million yuan in crude oil revenue, effectively reducing the emission intensity of greenhouse gases such as CO2 and significantly improving the efficiency of heavy oil production and the economic benefits of heavy oil resources.

[0055] Example 2

[0056] Build a 5 square kilometer clean energy power generation and storage system, with an annual production time of 300 days and an annual power generation of 314 million kWh; the reforming and separation system 5 hydrogenates and reforms 500 tons of crude oil every day and processes 150,000 tons of extra-heavy oil annually. The extra-heavy oil is reformed at a hydrogenation ratio of 3% (mass). Through the optimization of the intelligent control system 6, ensure that the hydrogen production system 3 produces 15 tons of hydrogen every day and 4,500 tons of green hydrogen annually.

[0057] According to the existing hydrogen production process level of electrolysis of alkaline water, 1.0Nm 3 Hydrogen consumes an average of 5 kWh of electricity. The intelligent control system 6 implements real-time intelligent scheduling, clean energy power generation and storage system, and backup power grid 1 automatically switch according to seasonal changes in light intensity and duration, changes in day and night, or changes in wind speed. It consumes 252 million kWh of green electricity on site throughout the year, and the remaining 62 million kWh of electricity is used for oil field production and operation, reducing the scale of thermal power generation.

[0058] The reforming and separation system 5 produces 50 tons of light hydrocarbon solvents per day, and produces 15,000 tons of light hydrocarbon solvents, 136,500 tons of light oil, and 3,000 tons of residual oil per year. The 50 tons of light hydrocarbon solvents produced per day can be injected into 5 well groups to produce heavy oil by solvent-assisted SAGD, electric heating solvent extraction, etc.

[0059] The intelligent control system 6 monitors and warns of security risks of the connected system in real time, automatically identifies and judges abnormal parameters, intelligently matches the optimal operating parameters, reduces energy consumption, and realizes green and low-carbon operation.

[0060] The newly mined extra-heavy oil is transported to the crude oil processing equipment and then goes through processes such as dehydration, desalting, and impurity removal before entering the upgrading and separation system 5 as a raw material to continue producing light hydrocarbon solvents and light oil. The light hydrocarbon solvent is injected into the mining system 4 for mining heavy oil in a green and low-carbon manner. The 136,500 tons of light oil produced annually are directly sold to the outside world. When the international oil price is US$80 per barrel, the price of light oil is RMB 600 per ton higher than that of heavy oil, and the direct sales revenue increases by RMB 81.9 million per year.

[0061] Light hydrocarbon injection production system 4 can reduce steam consumption by 54,000 tons and 3.6 million Nm per year 3Natural gas consumption is equivalent to reducing CO2 emissions by 6,800 tons. The market price of steam is 100 yuan / ton, saving 5.4 million yuan in steam costs each year. The estimated recovery rate of the 45 SAGD well groups in the mining system will increase from 45% to 60% over the entire life cycle, which can increase crude oil production by 187,500 tons and generate direct income of 750 million yuan. It will significantly reduce the emission intensity of greenhouse gases such as CO2 and significantly improve the efficiency of heavy oil production and the economic benefits of heavy oil resources.

[0062] Example 3

[0063] Build an 8 square kilometer clean energy power generation and storage system, with an annual production time of 300 days and an annual power generation of 500 million kWh; the reforming and separation system 5 hydrogenates and reforms 1,500 tons of crude oil every day and processes 450,000 tons of extra-heavy oil annually. The extra-heavy oil is reformed at a hydrogenation ratio of 3% (mass). Through the optimization of the intelligent control system 6, ensure that the hydrogen production system 3 produces 45 tons of hydrogen every day and 13,500 tons of green hydrogen annually.

[0064] According to the existing proton exchange membrane water electrolysis hydrogen production process level, 1.0Nm 3 Hydrogen consumes an average of 4 kWh of electricity. The intelligent control system 6 implements real-time intelligent scheduling, automatic switching of the clean energy power generation and storage system and the backup power grid 1 according to seasonal changes in light intensity and duration, changes in day and night, or changes in wind speed. It can absorb 500 million kWh of green electricity locally throughout the year, and use 100 million kWh of electricity generated by green electricity or other means in other regions through the backup power grid 1.

[0065] The reforming and separation system 5 produces 150 tons of light hydrocarbon solvents per day, and produces 45,000 tons of light hydrocarbon solvents, 409,500 tons of light oil, and 9,000 tons of residual oil per year. The 150 tons of light hydrocarbon solvents produced per day can be injected into 15 well groups to carry out solvent-assisted SAGD, electric heating solvent extraction, solvent huff and puff, etc. to produce heavy oil.

[0066] The intelligent control system 6 monitors and warns of security risks of the connected system in real time, automatically identifies and judges abnormal parameters, intelligently matches the optimal operating parameters, reduces energy consumption, and realizes green and low-carbon operation.

[0067] The newly mined extra-heavy oil is transported to the crude oil processing equipment and undergoes processes such as dehydration, desalting, and impurity removal before entering the upgrading and separation system 5 as a raw material to continue producing light hydrocarbon solvents and light oil. The light hydrocarbon solvent is injected into the mining system 4 for the green and low-carbon mining of heavy oil. The 409,500 tons of light oil produced annually is directly sold to the sales system. When the international oil price is US$100 per barrel, the price of light oil is RMB 800 per ton higher than that of heavy oil, and the direct sales revenue increases by RMB 327 million per year.

[0068] Light hydrocarbon injection production system 4 can reduce steam consumption by 160,000 tons and 10.8 million Nm per year3 Natural gas consumption is equivalent to reducing CO2 emissions by 20,000 tons. The market price of steam is 100 yuan / ton, saving 16 million yuan in steam costs each year. The estimated recovery rate of 415 SAGD well groups in the mining system will increase from 45% to 60% over the entire life cycle, and the production of crude oil can be increased by 562,500 tons. The direct income from the increased production of crude oil is 2.83 billion yuan, which significantly reduces the emission intensity of greenhouse gases such as CO2 and significantly improves the efficiency of heavy oil production and the economic benefits of heavy oil resources.

[0069] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A low-carbon cycle production method for super heavy oil, characterized by: The following steps are involved: S1: Power generation: Use clean energy to generate electricity; S2: Oil recovery: Inject steam into the oil layer to recover extra-heavy oil resources; S3: Hydrogen production: using the electricity generated in S1 to produce hydrogen by electrolysis; S4: Upgrading: Using the hydrogen produced in S3 to upgrade the super heavy oil produced in S2, obtain and separate light hydrocarbon solvent and light oil; S5: Harvest light oil; inject the light hydrocarbon solvent separated in S4 into the oil layer instead of the steam in S2 to exploit the super heavy oil resources.

2. The method for low-carbon recycling of super heavy oil according to claim 1, characterized in that: The S1 also includes storing the obtained electric energy by using an electric storage device, and the clean energy includes wind energy and / or solar energy.

3. A low-carbon cycle production method for super heavy oil according to claim 2, characterized in that: The stored electrical energy is used for extra heavy oil production operations in S2.

4. The method for low-carbon recycling of super heavy oil according to claim 1, characterized in that: The S3 also includes compressing and storing the produced hydrogen using a hydrogen storage device.

5. The method for low-carbon recycling of super heavy oil according to claim 1, characterized in that: After S5, the process further includes: recovering the light hydrocarbon solvent in the produced extra heavy oil resources, and re-investing the recovered light hydrocarbon solvent in S2 to inject it into the oil layer for producing extra heavy oil.

6. The method for low-carbon recycling of super heavy oil according to claim 1, characterized in that: An intelligent control system is used to control the process of S1-S5.

7. A system for implementing the low-carbon cycle recovery method for ultra-heavy oil according to any one of claims 1 to 6, characterized in that: Including clean energy power generation system, hydrogen production system, mining system, reforming and separation system; The clean energy power generation system is electrically connected to the hydrogen production system and the mining system, and the reforming and separation system is connected between the hydrogen production system and the mining system, wherein the outlet of the reforming and separation system is connected to the inlet of the mining system, and the outlet of the mining system is connected to the inlet of the reforming and separation system, and a crude oil processing device is connected between the outlet of the mining system and the inlet of the separation system.

8. A system for a low-carbon cycle recovery method for ultra-heavy oil as claimed in claim 7, characterized in that: It also includes a backup power grid, to which the hydrogen production system is also connected.

9. A system for a low-carbon recycling method for super-heavy oil production as claimed in claim 7, characterized in that: It also includes an intelligent control system, which is connected to the clean energy power generation system, hydrogen production system, mining system, and reforming and separation system by electrical signals.

10. A system for a low-carbon cycle recovery method for ultra-heavy oil as claimed in claim 7, characterized in that: A solvent recovery device is connected between the crude oil processing device and the outlet of the production system, and the solvent recovery device is also connected to the inlet of the production system.

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