Carbon-reduction-type SAGD plant system using green hydrogen

Abstract

The present invention relates to a carbon-reduction-type steam-assisted gravity drainage (SAGD) plant system using green hydrogen, in which, in recovering oil components from oil sands buried underground, on the basis of the most common SAGD technology among technologies for bitumen recovery from oil sands, instead of an expanding solvent-SAGD (ES-SAGD) method using steam and natural gas and using additives (solvents, etc.) so as to reduce a stem-oil ratio (SOR) that affects environmental pollution, by using only a natural gas mix and steam of eco-friendly hydrogen generated by a water electrolysis device, bitumen can be recovered while significantly reducing greenhouse gases, which have been pointed out as the biggest issue so far.

Description

Carbon-reducing SAGD plant system utilizing green hydrogen

[0001] The present invention relates to a carbon reduction type SAGD plant system, and more specifically, to a technology that replaces ES-SAGD (Expanding Solvent SAGD), which is a method of using steam, natural gas, and additives (solvents, etc.) to reduce SOR (Steam Oil Ratio) that affects environmental pollution when recovering oil components from oil sand buried underground based on the SAGD (steam-assisted gravity drainage) technology, which is the most common method of recovering bitumen from oil sand, and a method of using additives (solvents, etc.) to reduce SOR (Steam Oil Ratio) that affects environmental pollution. The present invention relates to a technology for a carbon reduction SAGD plant system that utilizes green hydrogen that can recover bitumen while significantly reducing greenhouse gases, which have been pointed out as the biggest problem in the past, by mixing eco-friendly hydrogen generated by a water electrolyzer with natural gas and only steam.

[0002] Recently, with the rise in oil prices and the war in Ukraine, the need for oil has resurfaced, and unconventional oils such as oil sands plants in extreme environmental conditions are receiving renewed attention.

[0003] Bitumen, a type of petroleum product composed of natural hydrocarbon compounds, is a black semi-solid or liquid substance that dissolves in carbon dioxide or liquid hydrocarbons at room temperature. Various methods are being applied to recover bitumen, a residue generated during petroleum refining, from underground. However, due to the nature of oil production, environmental pollution, including greenhouse gas emissions, continues to be a major issue. Therefore, long-term pollution reduction measures are necessary, which is also a critical factor in determining the sustainability of the oil sands business.

[0004] The SAGD method, which currently accounts for more than 80% of the bitumen production method, uses a large amount of water (steam) and gas, which are major causes of environmental pollution and greenhouse gases. To reduce this, ES-SAGD (Expanding Solvent SAGD), a method that mixes high-grade refined oil such as solvent to reduce the amount of steam, is being applied.

[0005] This means that not only do harmful substances like H2S generate during the steam generation and bitumen treatment processes, but the large volumes of water required for steam generation are also largely dependent on the use of arbitrary wells or ponds. However, this method requires more than three times the amount of water as the oil produced, and even with water treatment, some contamination remains unavoidable.

[0006] Since the SAGD method itself uses a large amount of water and is a major cause of environmental pollution, ES-SAGD (Expanding Solvent SAGD) is sometimes applied to reduce the amount of steam by mixing high-grade refined oil such as solvent.

[0007] In applying SAGD or ES-SAGD technology to recover bitumen from oil sands buried underground, there is a need for a method that can significantly reduce greenhouse gases by mixing hydrogen and natural gas and injecting additives such as solvent and CO2, and improve the quality of bitumen through the hydrogenation reaction of the injected hydrogen.

[0008] The present invention was created in response to the above-mentioned needs, and the purpose of the present invention is to provide a carbon-reducing SAGD plant system utilizing green hydrogen that can significantly reduce SOR (Steam Oil Ratio) and greenhouse gases that affect environmental pollution by mixing hydrogen generated by a water electrolysis device including steam with natural gas to recover bitumen.

[0009] For the above purpose, the present invention is characterized by providing a plant system for recovering bitumen from an oil sand mine, comprising: a first water treatment module for removing impurities from feed water to produce purified water; a boiler module for heating the purified water to produce steam; a hydrogen generation module for generating hydrogen by decomposing the purified water using electricity; an injection well for supplying the steam into the oil sand mine; a hydrogen supply unit for supplying a portion of the hydrogen produced in the hydrogen generation module into the oil sand mine; a producer well for recovering bitumen and gas from the lower part of the oil sand mine; a first separator for separating the gas component and bitumen of the producer well; and an oil-water separation module for separating a water component from the bitumen passing through the first separator.

[0010] At this time, it is preferable that the boiler module further includes a second separator configured to use a portion of the hydrogen produced in the hydrogen generation module as fuel, and to generate reformed hydrogen through the gas component passing through the first separator.

[0011] In addition, it is preferable to further include a first gas mixing module that receives natural gas from the outside, is connected to the hydrogen supply unit, mixes natural gas and hydrogen at a set ratio, and supplies the mixture to the inside of the oil sand mine; and a second gas mixing module that mixes natural gas separated from the second separator and a portion of hydrogen produced from the hydrogen generation module at a set ratio and supplies the mixture as fuel for the boiler module.

[0012] In addition, it is preferable to further include a second water treatment module that treats water separated from the oil-water separation module and supplies it to the boiler module and hydrogen generation module.

[0013] In addition, it is preferable to further include a diluent treatment module having a diluent tank containing a diluent, a diluent supply unit that supplies the diluent to the oil-water separation module, and a diluent recovery unit that recovers the diluent from the bitumen that has passed through the oil-water separation module and supplies it to the diluent tank.

[0014] Through the present invention, instead of using ES-SAGD (Expanding Solvent SAGD), which is a method using additives (solvents, etc.), bitumen can be efficiently recovered from oil sands by mixing natural gas with eco-friendly hydrogen produced by an electrolyzer and steam alone, while significantly reducing greenhouse gases, which have been pointed out as the biggest problem in the past.

[0015] In particular, combining it with green hydrogen production can reduce carbon dioxide emissions by 20-40%, thereby mitigating carbon dioxide costs associated with carbon emissions credits. Furthermore, it offers a wide range of applications, including reducing NOx emissions through hydrogen purification and utilizing hydrogen fuel cells and generated hydrogen as the primary power source for plants.

[0016] In addition, it can significantly contribute to the realization of P2G (Power to Gas) by enabling the continuous storage and recovery of hydrogen in underground caverns where bitumen has been created using the SAGD method.

[0017] Figure 1 is a conceptual diagram of ES-SAGD production according to conventional technology.

[0018] Figure 2 is a production system diagram of ES-SAGD according to the prior art;

[0019] Figures 3 and 4 are a schematic diagram of a SAGD production system using hydrogen according to an embodiment of the invention.

[0020] Figures 5 and 6 are schematic diagrams of a SAGD production system utilizing hydrogen according to another embodiment of the present invention.

[0021] The configuration of a carbon reduction SAGD plant system utilizing green hydrogen of the present invention is specifically described with reference to the attached drawings below.

[0022] Figure 1 is a conceptual diagram of ES-SAGD production according to conventional technology, and Figure 2 is a schematic diagram of ES-SAGD production according to conventional technology.

[0023] The SAGD method requires a complex series of processes to mine the bitumen solidified underground in the oil sands and use it as crude oil. This process requires a large amount of water, electricity, and gas, and environmental pollution occurs due to steam and gas during the processing.

[0024] In particular, the factors that have the greatest impact on greenhouse gases are methane from steam and natural gas. Lower values ​​for the steam-to-oil production ratio (SOR) and the gas-to-oil production ratio (GOR) are more advantageous in terms of environmental pollution and economic feasibility. Recently, in-situ methods (underground recovery methods) have been applied to lower SOR and GOR, such as the ES-SAGD method, which mixes solvent with steam to reduce the natural gas content while increasing bitumen mining productivity.

[0025] The ES-SAGD plant is almost identical to the SAGD method, but includes an injection well for injecting gas, steam, and solvent for underground recovery, a production well for recovering bitumen from underground, a well pad device as a basic separation and treatment device, an oil-water separator in the central process facility (CPF), a water treatment device, a boiler package for generating steam, and a device for injecting and recovering solvent. Partial reforming treatment is also performed as needed.

[0026] Additionally, water, the source of steam production, is obtained from source water obtained from the natural environment and tailing water after oil sands processing, and is supplied after being treated as Boiler Fresh Water (BFW). In other words, since continuous water production is required to supply BFW for steam, sufficient water can be secured based on electrolysis for hydrogen production, which is a feature of the present invention.

[0027] The present invention uses a method of recovering bitumen from oil sands by mixing hydrogen generated by a water electrolysis device with natural gas to reduce greenhouse gases, which is pointed out as the biggest problem in the method of recovering bitumen from oil sands. To this end, based on the SAGD (steam-assisted gravity drainage) technology, which is the most common among the various production methods for producing bitumen, ES-SAGD (Expanding Solvent-assisted Gravity Drainage) is a method of recovering oil components from oil sands buried underground using steam, natural gas, and additives (solvents, etc.) used to reduce SOR (Steam Oil Ratio) that affects environmental pollution. Instead of SAGD, it recovers bitumen while significantly reducing greenhouse gases by mixing hydrogen and natural gas, which are eco-friendly raw materials, and only using steam. The reason why hydrogen is effective in the SAGD method is because hydrogen has a high heat capacity, which is higher than steam. In other words, it can potentially transfer more heat to the reservoir, thereby increasing the oil recovery rate. Next, hydrogen can be used for in-situ combustion, which is a process of generating heat by reacting with oil in the reservoir and creating conditions that promote oil flow. In addition, unlike traditional combustion processes that use natural gas, hydrogen combustion only produces water vapor as a byproduct, thereby reducing greenhouse gas emissions related to the extraction process. It can potentially reduce greenhouse gas emissions.

[0028] Figures 3 and 4 are schematic diagrams of a SAGD production system utilizing hydrogen according to an embodiment of the invention. The present invention relates to a plant system for recovering bitumen from an oil sands mine, which essentially supplies steam and hydrogen to the oil sands mine and recovers bitumen. Furthermore, instead of traditional natural gas-powered steam generators, the present invention utilizes a hydrogen boiler, which directly supplies and uses hydrogen and is currently in the commercialization stage, to generate steam in an environmentally friendly manner.

[0029] Figures 5 and 6 illustrate a hydrogen-based SAGD production system according to another embodiment of the present invention. The system illustrates a method of replacing the solvent used with steam and natural gas in conventional SAGD processes with hydrogen in areas where nearby natural gas production is possible or natural gas is readily available through gas pipelines, by mixing it with natural gas, as described in the embodiment illustrated in Figures 3 and 4.

[0030] To this end, a first water treatment module (101) is provided to remove impurities from the supply water to generate purified water for steam generation and hydrogen production. As previously mentioned, the supply water can be source water obtained from natural environments such as ponds, reservoirs, and rivers, and tailing water existing in a mine after oil sands processing. Impurities are removed through the first water treatment module (101) to supply BFW (Boiler Fresh Water) and water for electrolysis hydrogen production described below. In an embodiment of the present invention, a system is proposed in which 211 BPD (Barrel Per Day) of purified water is generated from 222 BPD (Barrel Per Day) of supply water.

[0031] At this time, the water obtained from the tailing water can be supplied to the skim tank of the second water treatment module (108) and the hydrogen generation module (103) described later through the first branch (118).

[0032] Additionally, BFW (Boiler Fresh Water) can be supplied to the boiler module (102) and the hydrogen generation module (103) through the second branch (119).

[0033] Afterwards, the purified water from which impurities have been removed by passing through the first water treatment module (101) is heated through the boiler module (102) to produce steam. Initially, steam is produced only through the purified water that has passed through the first water treatment module (101), but water for steam production can also be supplied to the boiler through the second water treatment module (113) as described below. In the embodiment of the present invention, the system is designed so that 211 BPD of water can be supplied as purified water for steam and hydrogen production through the first water treatment module (101), 705 BPD through the second water treatment module (113), and a total of 916 BPD of water can be supplied, and 870 BPD of steam can be produced through the boiler module (102).

[0034] In addition, a portion of the purified water from which impurities have been removed by passing through the first water treatment module (101) is decomposed using electricity in the hydrogen generation module (103) to generate hydrogen. To this end, the hydrogen generation module (103) is equipped with electricity, a catalyst, and a separation membrane to electrolyze purified water, and recently, a non-catalytic hydrogen generation technology that does not use expensive catalysts using platinum, iridium, ruthenium, etc. can be applied to increase competitiveness.

[0035] In an embodiment of the present invention, 1 kg of hydrogen can be produced from 9 kg of water, and since 1 bbl / d = 6.62 kg / h, 14.5 kg / h of hydrogen can be produced from 20 bbl / d = 132 kg / h of purified water, and 162 M3 of hydrogen gas can be supplied per hour with 132 kg of water.

[0036] At this time, the power for water electrolysis uses electricity generated from renewable energy sources such as solar or wind power, and can produce green hydrogen, which is the most necessary future energy source in the carbon neutral era, with hydrogen that emits no carbon emissions during the production process. In particular, with the recent decline in the price of renewable energy, the effect of green hydrogen can be greatly increased, and the boiler module (102) can be configured to use a portion of the hydrogen produced in the hydrogen generation module (103) as fuel, thereby improving the efficiency of the entire system.

[0037] A portion of the hydrogen produced through the hydrogen generation module (103) is supplied to the inside of the oil sand mine and used as fuel for the boiler module (102), and the remainder is stored in the H2Sales Tank and can be utilized in various ways.

[0038] The steam produced through the above boiler module (102) is supplied to the inside of the oil sand mine through the injection well (105), and a portion of the hydrogen produced in the hydrogen generation module (103) is also supplied to the inside of the oil sand mine through the hydrogen supply unit (104). As mentioned above, 870 BPD of steam and 100 MCF / day (2,832 M 3 ) hydrogen is supplied into the oil sand mine.

[0039] Through this, bitumen and gas are recovered from the producer well (106) installed at the bottom of the oil sand mine, and the gas component and bitumen of the producer well (106) are separated through the first separator (107). At this time, the bitumen is a mixture of the oil component of the bitumen and the water resulting from the steam supplied to the oil sand mine, and the gas component is a mixture of hydrogen supplied to the oil sand mine, as well as natural gas originally present in the mine or supplied separately mixed with hydrogen. Since the gas component and bitumen of the producer well (106) are in different states, the first separator (107) easily separates the gas component and bitumen by utilizing the principle of separating gas and non-gas components.

[0040] In an embodiment of the present invention, the bitumen recovered from the producer well (106) and separated through the first separator (107) is at a total level of 1083 BPD, which can be said to be a mixed state of 300 BPD of oil component and 783 BPD of water. Accordingly, the water component among the bitumen that passed through the first separator is separated through the oil-water separation module (108).

[0041] To this end, the bitumen separated through the first separator (107) is transported through a sludge pump and supplied to the oil-water separation module (108), and sand removal and dehydration can be performed during this process. In the embodiment of the present invention, the oil-water separation module (108) uses FWKO (Free Water Knockout), and a desalination module (109) is provided so that desalination treatment of the bitumen from which water has been separated can be performed.

[0042] The water separated through the above oil-water separation module (108) passes through a skim tank and is treated through a second water treatment module (113) consisting of an IGF (Induced Gas Floatation). In addition, the water separated from the oil-water separation module (108) is supplied to the boiler module (102) and the hydrogen generation module (103). At this time, the skim tank can additionally receive water through the first branch unit (118).

[0043] The above IGF refers to a water treatment process that purifies wastewater (or other water) by removing suspended solids such as oil and solids. This includes ceramic membrane filters, reverse osmosis (RO) filters, and capacitive deionization (CDI), which uses electrical energy to remove ions and utilizes the supercapacitor principle to efficiently and cost-effectively purify wastewater and dechlorinate it. Furthermore, Zero Liquid Discharge (ZLD) technology, which recirculates concentrated water generated from RO without discharging any effluent, allows for the discharge and disposal of the sludge contained therein.

[0044] In order to improve the efficiency of the above oil-water separation module (108), a diluent treatment module (114) may be included, which includes a diluent tank (115) containing a diluent, a diluent supply unit (118) that supplies the diluent to the oil-water separation module (108), and a diluent recovery unit (117) that recovers the diluent from the bitumen that has passed through the oil-water separation module (108) and supplies it to the diluent tank (115).

[0045] That is, the diluent of the above diluent tank (115) is supplied to the rear of the pre-head desander for sand removal and dewatering, and the diluent is recovered from the bitumen that has passed through the oil-water separation module (108) and supplied again, thereby circulating the diluent, thereby increasing the separation efficiency of water and oil components to 97%.

[0046] At this time, the diluent may vary depending on the bitumen detailed components, and C4 (butane), C5 (pentene), and C6 (hexene) can be used depending on the various forms of hydrocarbons, and the diluent is used during SAGD processing to help in the effective separation and production of crude oil and water.

[0047] In SAGD, crude oil is produced using steam-assisted gravity drainage. Because crude oil contains a significant amount of water along with steam, the crude oil-water mixture must be separated. Diluents lower the surface tension between the oil and water, facilitating fluid separation. This facilitates water separation from the crude oil and facilitates efficient oil collection. Furthermore, high viscosity can impede fluid flow, so diluents can improve flow characteristics by reducing the viscosity of non-smoothing fluids with high viscosity.

[0048] In addition, the gas component that has passed through the first separator (107) can be utilized as fuel gas together with the gas component that has been partially removed through the oil-water separation module (108). In addition, since the gas component that has passed through the first separator (107) is mixed with natural gas and hydrogen as main components, a second separator (110) that generates reformed hydrogen through the gas component that has passed through the first separator (107) can be provided to generate hydrogen. In addition, some of the gas component that has passed through the first separator (107) can be used as fuel for the boiler module (102).

[0049] As mentioned above, in cases where natural gas supply from outside is smooth, the natural gas supply may be connected to the hydrogen supply unit, and a first gas mixing module (111) may be provided to mix natural gas and hydrogen at a set ratio and supply them to the inside of the oil sand mine. Preferably, by mixing natural gas and hydrogen at a ratio of 70:30 to 90:10, the bitumen recovery efficiency can be significantly improved.

[0050] In addition, a second gas mixing module (112) that mixes the natural gas separated from the second separator (110) and a portion of the hydrogen produced in the hydrogen generation module at a set ratio and supplies the mixture as fuel for the boiler module can be further included to reduce energy waste and increase efficiency. In this case, it is preferable to mix the natural gas and hydrogen at a ratio of 60:40 to 80:20.

[0051] This invention system can reduce greenhouse gas emissions in unconventional oil production areas, which are among the most vulnerable to greenhouse gas emissions, by utilizing green hydrogen, while simultaneously achieving P2G by storing and supplying green hydrogen. Furthermore, it can transform unconventional oil plants into new types of plants capable of simultaneously producing and utilizing essential oil for industry and green hydrogen, essential for combating future global warming.

[0052] If 10 vol% hydrogen is mixed into Korea's annual natural gas consumption of 40 million tons, natural gas consumption can be reduced by 1.29 million tons per year, resulting in a reduction of 3.55 million tons of carbon dioxide emissions per year. Furthermore, with rising environmental pollution restrictions in Canada and other unconventional oil reserve regions, unconventional oil production is expected to decline significantly in the future. However, the application of a production system utilizing green hydrogen according to the present invention can provide an environmentally friendly solution to unconventional oil production, and the hydrogenation reaction, one of the characteristics of hydrogen, can also significantly improve bitumen quality.

Claims

1. In a plant system for recovering bitumen from an oil sand mine, A first water treatment module that removes impurities from the supply water to produce purified water; A boiler module that heats the purified water to produce steam; A hydrogen generation module that generates hydrogen by decomposing the purified water using electricity; An injection well that supplies the above steam into the inside of an oil sand mine; A hydrogen supply unit that supplies a portion of the hydrogen produced in the above hydrogen generation module to the inside of the oil sand mine; Producer well where bitumen and gas are recovered from the bottom of an oil sands mine; A first separator for separating the gas component and bitumen of the above producer well; A carbon reduction SAGD plant system utilizing green hydrogen, characterized by comprising: an oil-water separation module for separating water components from the bitumen passing through the first separator; 2. In paragraph 1, The above boiler module is configured to use a portion of the hydrogen produced in the above hydrogen generation module as fuel, A carbon reduction SAGD plant system utilizing green hydrogen, characterized by further including a second separator that generates reformed hydrogen through gas components passing through the first separator.

3. In paragraph 1, A first gas mixing module that receives natural gas from the outside, is connected to the hydrogen supply unit, mixes natural gas and hydrogen at a set ratio, and supplies the mixture to the inside of an oil sand mine; A carbon reduction SAGD plant system utilizing green hydrogen, characterized in that it further includes a second gas mixing module that mixes natural gas separated from the second separator and a portion of hydrogen produced from the hydrogen generation module at a set ratio and supplies the mixture as fuel for the boiler module.

4. In paragraph 1, A carbon reduction SAGD plant system utilizing green hydrogen, characterized by further including a second water treatment module that treats water separated from the water separation module and supplies it to the boiler module and hydrogen generation module.

5. In paragraph 1, A carbon reduction SAGD plant system utilizing green hydrogen, characterized by further comprising a diluent treatment module having a diluent tank containing a diluent, a diluent supply unit supplying the diluent to the oil-water separation module, and a diluent recovery unit recovering the diluent from the bitumen passing through the oil-water separation module and supplying it to the diluent tank.

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