Net zero carbon fossil energy production method, CCS system and blue carbon power station

Abstract

The invention relates to a net zero carbon fossil energy production method, a CCS system and a blue carbon power station technology, which are an energy transformation engineering technical solution based on nature, and are driven by only natural seawater and carbon-free electric power to implement deep seawater absorption carbon capture and bicarbonate radical ion type ocean carbon sequestration on fossil energy of a coastal power station and the like; the whole process conforms to the current international convention and environmental protection regulations, the marine ecological environment is friendly, green and low-carbon transformation of fossil energy of a fuel gas, fuel oil and coal-fired power plant can be achieved with extremely low cost, the fossil energy can be fused with renewable energy to achieve win-win development, and the method has a great significance in large-scale utilization of marine natural carbon sink power stations necessary for achieving the 2050 net zero carbon emission climate target. And necessary conditions are created.

Description

Net-zero carbon fossil energy production methods, CCS systems, and blue carbon power plants Technical Field

[0001] The net-zero-carbon fossil energy production method, CCS system and blue carbon power station of the present invention belong to the fields of climate energy transition technology and marine engineering technology, and specifically relate to net-zero-carbon fossil energy production technology based on carbon capture and storage (CCS). Background Art

[0002] The clean, low-carbon transition to fossil energy and the development of renewable energy have long been considered two key pillars essential for achieving the Paris climate goal of net-zero carbon emissions by 2050. However, while renewable energy has made significant progress, with declining costs and increasing scale, the clean, low-carbon transition to fossil energy has stagnated. A 2016 report by the International Energy Agency (IEA) concluded that to achieve net-zero carbon emissions, hundreds of commercial carbon capture and storage (CCS) power plant projects—a key technological enabler for the clean, low-carbon transition to fossil energy—will be needed by 2020 and thousands by 2050. However, as of March 2023, only one coal-fired power plant had been commissioned worldwide, and it closed in 2020 due to fundamental cost inequality. Furthermore, gas-fired power plants, which have a greater impact on carbon emissions, have not been commissioned globally. In the 30 years of global climate mitigation efforts, CCS solutions have consistently failed to overcome the challenges of cost and scale.

[0003] The limiting factor in mitigation costs is the affordability of carbon capture materials and energy consumption: various carbon capture technologies that have been under trial rely heavily on artificial chemical absorbents, and their structural characteristics of high material and energy consumption are difficult to change. The limiting factor in mitigation scale is the available scale of carbon sinks required for carbon sequestration. Since the international collaborative experiment on "molecular" CO2 marine carbon sequestration was suspended / terminated in 2002 due to regulations and marine ecological and environmental issues, almost all carbon sequestration technology trials and demonstrations have relied heavily on geological (including submarine geological) carbon sequestration, which accounts for less than 5% of the Earth's natural carbon sink, and recycling and "utilization" as a temporary carbon storage method. There is a structural gap between the scale of available carbon sinks and the scale required for a net-zero carbon climate goal. Moreover, the overall structural flaws of CCS are prominent: the carbon capture and storage technology links are independent of each other, not forming a continuous CCS chain, unable to ensure end-to-end coordination and "source-sink matching". Instead, they operate independently and restrict each other, resulting in further increases in the overall cost of CCS and a further reduction in the scale of available carbon sinks.

[0004] Since the Paris Agreement, the concept of "blue carbon" aimed at utilizing the ocean's natural carbon sinks has become increasingly popular, showing that the massive amount of carbon dioxide emissions reduction / negative emissions required to achieve the net zero carbon goal must be stored by a massive natural ocean carbon sink (accounting for >93% of the Earth's natural carbon sink). This basic logic of climate mitigation, after the United Nations Framework Convention on Climate Change (UNFCCC) made requirements and commitments for the sustainable use of marine ecosystem (biological and abiotic factors) carbon sinks, and the United Nations Intergovernmental Panel on Climate Change (IPCC) proposed that the use of marine natural carbon sinks will constitute the most cost-effective mitigation solution. After being shelved for more than 10 years due to the failure of early trials, this field is re-understanding and exploring new technologies for the utilization of marine natural carbon sinks.

[0005] However, many of the technical solutions currently proposed under the concept of "blue carbon" are basically limited to the edge of the "blue carbon" concept - the use of "coastal carbon sinks". They only rely on the biological carbon sinks of coastal vegetation such as mangroves, seagrasses, and seaweeds to naturally absorb CO2 from the air, and cannot be used for carbon emission reduction in other situations. Even for applicable negative emissions (direct carbon capture from the air) scenarios, because marine biological carbon sinks account for a very small proportion of marine ecosystem carbon sinks, and the contact area between coastal areas and the air is more than two orders of magnitude smaller than the entire ocean / atmosphere interface, the theoretical scale of coastal biological carbon sinks is very limited. In addition, due to many limiting factors such as most coastal organisms being immersed in marine waters and unable to contact the air, the actual scale of carbon sinks that can be obtained is even smaller. Obviously, the "utilization of natural marine carbon sinks as the most cost-effective mitigation solution" proposed by the IPCC is a technical problem that people in this field have always been eager to solve but have never been successful.

[0006] As a targeted solution, the seawater CCS technology (patent number: US 11,045,785 B2), proposed in 2016, builds on experience and knowledge gained from FGD development and discloses a CO2 reduction (and negative emissions) technology solution that leverages the natural carbon sinks of marine ecosystems: carbon capture using only seawater scrubbing (zero artificial chemical additions) and carbon sequestration due to the ocean's natural alkalinity. However, this technology still falls short of the requirements for increasing the depth of decarbonization and accelerating large-scale deployment required to achieve the 2050 net-zero carbon climate goal.

[0007] Summary of the Invention

[0008] The first purpose of the present invention is to overcome the shortcomings of existing carbon capture technologies and provide a power plant-scale, extremely low-cost deep carbon capture technology solution for fossil energy.

[0009] The second object of the present invention is to overcome the shortcomings of existing carbon sequestration technologies and provide an eco-friendly and environmentally friendly, ultra-low-cost marine carbon sequestration technology solution at a power plant scale.

[0010] The third object of the present invention is to overcome the shortcomings of existing carbon capture and storage (CCS) technology and provide a full-process, power plant-scale, and extremely low-cost carbon capture and storage technology solution;

[0011] The fourth object of the present invention is to overcome the shortcomings of the existing technology and provide a natural-based, full-process carbon capture and storage technology solution with zero artificial chemical additions;

[0012] The fifth object of the present invention is to overcome the shortcomings of existing technologies and provide a climate mitigation technology solution that integrates clean energy and renewable energy for win-win development;

[0013] The overall purpose of this invention is to overcome the shortcomings of the existing technology and provide a blue carbon power plant engineering technology solution that can utilize the carbon sinks of marine ecosystems (biological and abiotic factors) on a large scale and accelerate the deployment, creating the necessary conditions for obtaining massive natural carbon sinks for the net zero carbon emission climate goal.

[0014] The technical solution of the net zero carbon fossil energy production method of the present invention includes the following steps:

[0015] 1) Burning fossil fuels to produce energy and fossil fuel flue gas;

[0016] 2) pre-treating the fossil fuel flue gas by cooling and / or desulfurizing to generate pre-treated flue gas;

[0017] 3) using decarbonized absorption seawater to capture carbon from the pretreated flue gas, thereby generating decarbonized absorption seawater and decarbonized gas;

[0018] 4) discharging the decarbonized gas into the atmosphere;

[0019] 5) Injecting decarbonized seawater into the ocean for carbon sequestration;

[0020] A further technical solution is that the method further comprises:

[0021] The fossil fuel is selected from one or more of natural gas, fuel oil and coal.

[0022] The energy source is one or more of electrical energy, thermal energy, mechanical energy, and hydrogen energy.

[0023] The combustion of the fossil fuel relies on air to assist combustion, and the pressure of the carbon-containing high-temperature flue gas produced is normal pressure, that is, atmospheric pressure.

[0024] In the step 2), the fossil fuel flue gas is washed with pretreated seawater to achieve cooling and / or desulfurization pretreatment.

[0025] The temperature of the flue gas after the pretreatment is not higher than 50°C, or not higher than 30°C, or not higher than 20°C, or not higher than 10°C, or not higher than 5°C than the temperature of the decarbonized and absorbed seawater;

[0026] The SO2 volume content of the flue gas after the pretreatment is less than 100 ppm, or less than 80 ppm, or less than 30 ppm.

[0027] The pretreated seawater is extracted from the ocean.

[0028] The pretreated seawater is obtained from the secondary utilization of process wastewater such as cooling seawater from power plants.

[0029] The pretreatment is replaced by the original flue gas desulfurization (FGD) process of the fossil energy system.

[0030] The carbon dioxide equivalent (CO2e) in the absorbed and captured fossil fuel flue gas is detected and measured by detecting and measuring the difference between the CO2 content of the fossil fuel flue gas and the CO2 content of the desulfurized gas; the CO2e measurement data is transmitted to the carbon accounting system in real time or periodically.

[0031] In the step 3), the area where the seawater absorbs and captures carbon is connected to the atmosphere.

[0032] A packing layer is provided. In step 3), the pretreated flue gas flows through the packing layer, and the decarbonized and absorbed seawater flows downward through the packing layer due to gravity potential energy, thereby absorbing and capturing carbon in the seawater.

[0033] In the step 3), the washing is carried out above sea level, and the decarbonization absorption seawater is extracted from the ocean.

[0034] In the step 5), before the decarbonized and absorbed seawater is discharged into the ocean, it is first mixed with neutralized seawater to form mixed seawater, so that the pH value is increased to meet the statutory discharge standards.

[0035] The aforementioned compliance with statutory emission standards refers to compliance with the emission standards permitted by the regulations governing the area where the drainage is located, including the IMO MEPC rules under the United Nations MARPOL Convention and the pH limits in the EPA VGP rules governing North America.

[0036] The regulations allow discharge standards to include discharge mixing zones designated by environmental law enforcement authorities in the area where the drainage is located.

[0037] In the discharged seawater that meets the legal discharge standards, the CO2 absorbed by the seawater has been converted into incremental bicarbonate ions (HCO3 — ) - the natural and main form of carbon in the ocean, and the step 5) is injected into the ocean to achieve ocean ionic carbon sequestration.

[0038] In the step 5), the decarbonized and absorbed seawater is discharged into the seawater below the sea surface through a drainage pipe by its own weight.

[0039] The pre-processor / decarbonization absorption tower / discharge equipment are all operated at normal pressure (atmospheric pressure), and the drainage of the equipment flows into the next process by its own weight and / or is injected into the ocean.

[0040] Provide CCS offshore platform.

[0041] Any one or more of the steps of pretreatment, decarbonization absorption, neutralization, etc. are carried out on an offshore CCS marine platform to help reduce the pumping height and energy consumption of the seawater.

[0042] The decarbonization and absorption of seawater and / or the neutralization of seawater adopts a high-flow and low-lift pumping method to reduce pumping height and energy consumption.

[0043] The height of the decarbonization absorption seawater pumping, that is, the height of the decarbonization absorption tower water distributor relative to the actual sea level, is not higher than 50m, or 30m, or 25m, or 20m, or 15m, or 10m, or 9m, or 8m, or 7m, or 6m, or 5m, or 4m, or 3m, or 2m, or 1m, or 0.5m.

[0044] The neutralized seawater is extracted from the ocean.

[0045] The neutralized seawater pumping height, that is, the height of the neutralizer liquid level relative to the actual sea level, is not higher than 10m, or 9m, or 8m, or 7m, or 6m, or 5m, or 4m, or 3m, or 2m, or 1m, or 0.5m, or 0.2m.

[0046] The decarbonized seawater is extracted from the ocean using a deep water extraction method.

[0047] The depth at which the decarbonized absorption seawater is extracted from the ocean is not less than 0.5m, or not less than 1m, or not less than 3m, or not less than 5m, or not less than 10m, or not less than 15m, or not less than 20m, or not less than 30m, or not less than 50m, or not less than 100m, or not less than 200m, or not less than 300m, or not less than 500m, or not less than 1000m, or not less than 2000m relative to the actual sea level.

[0048] In the step 3), the ratio of the flow rate of the decarbonized and absorbed seawater to the flow rate of the fossil fuel flue gas is adjusted so that the pH value of the seawater after decarbonization and absorption meets the statutory emission standards.

[0049] In the step 5), before the decarbonized and absorbed seawater is discharged into the ocean, it is first mixed with neutralized seawater to form mixed seawater, so that the pH value is increased to meet the statutory discharge standards.

[0050] Providing carbon-free energy generation.

[0051] The seawater pump that extracts and pumps decarbonized absorbed seawater and / or neutralized seawater and / or pretreated seawater from the ocean is driven by a carbon-free energy power generation system.

[0052] The carbon-free energy includes one or more of wind energy, solar energy, wave energy, tidal energy, and nuclear energy.

[0053] The carbon-free energy generation system includes an energy storage method to ensure uninterrupted power supply.

[0054] Direct air carbon capture and storage (DACCS) is provided, wherein the amount of carbon dioxide directly captured and stored from the atmosphere by the DACCS is equal to the amount of carbon dioxide emitted into the atmosphere by the decarbonized gas in step 4), so as to achieve net zero carbon emission fossil energy production from an overall effect.

[0055] The carbon capture and storage (CCS) system technical solution of the present invention comprises:

[0056] A pre-processor, which performs cooling and / or desulfurization pre-treatment on the fossil fuel flue gas to generate pre-treated flue gas;

[0057] a decarbonization absorption tower, which uses decarbonization absorption seawater to wash the pretreated flue gas to absorb and capture carbon dioxide, generating decarbonization absorption seawater and decarbonization gas, and discharging the decarbonization gas into the atmosphere;

[0058] Decarbonized absorption seawater supply equipment, used to pump seawater extracted from the ocean to the decarbonized absorption tower to become decarbonized absorption seawater;

[0059] Discharge equipment is used to discharge the decarbonized and absorbed seawater into the ocean for carbon sequestration.

[0060] Further technical solutions are:

[0061] The fossil fuel is selected from one or more of natural gas, fuel oil and coal.

[0062] The combustion device for generating fossil fuel flue gas includes a boiler, a combined cycle gas and steam turbine (CCGT), a waste heat boiler, and an internal combustion engine.

[0063] The pre-treater is configured to scrub the fossil fuel flue gas with pre-treated seawater to achieve cooling and / or desulfurization pre-treatment.

[0064] The pretreated seawater is extracted from the ocean.

[0065] The pretreated seawater comes from cooling seawater in a power plant.

[0066] In the flue gas after the pretreatment, the volume content of SO2 is less than 100 ppm, or less than 80 ppm, or less than 30 ppm.

[0067] The temperature of the flue gas after pretreatment is no higher than 50°C, or no higher than 30°C, or no higher than 20°C, or no higher than 10°C, or no higher than 5°C than the water temperature of the decarbonized absorption seawater.

[0068] The discharge equipment further comprises a neutralizer for mixing the decarbonized and absorbed seawater with the neutralized seawater to form mixed seawater, so that the pH value is increased to meet the statutory discharge standards.

[0069] The inner cavity area of ​​the decarbonization absorption tower used for washing is connected to the atmosphere through an exhaust pipe.

[0070] The internal pressure of the decarbonization absorption tower is normal pressure (atmospheric pressure).

[0071] The decarbonization absorption seawater is introduced into the decarbonization absorption tower from the upper part and falls downward by its own weight to contact the carbon-containing gas introduced into the tower, thereby washing the CO2 in the captured gas.

[0072] The decarbonization absorption tower is a packed absorption tower, which allows the decarbonization absorption seawater to contact with the carbon-containing gas through the packing layer to obtain a larger gas-liquid contact area, thereby improving the capture effect of CO2 washing and dissolution.

[0073] The filler is made of materials that can withstand high accident temperatures, including metals, ceramics, and polymer materials.

[0074] The discharge equipment includes a drain pipe, which is used to discharge the seawater after decarbonization and absorption into the seawater below the sea surface by relying on its own weight.

[0075] The pre-processor / decarbonization absorption tower / discharge equipment are all operated at normal pressure (atmospheric pressure), and the drainage of the equipment is configured to flow into the next process by relying on its own weight, and / or be injected into the ocean.

[0076] The decarbonization absorption tower includes a water distributor, and the height of the outlet of the water distributor relative to the actual sea level is not higher than 50m, or 30m, or 25m, or 20m, or 15m, or 10m, or 9m, or 8m, or 7m, or 6m, or 5m, or 4m, or 3m, or 2m, or 1m, or 0.5m.

[0077] The height of the neutralized seawater pumping, that is, the height of the neutralizer liquid level relative to the actual sea level, is not higher than 10m, or 9m, or 8m, or 7m, or 6m, or 5m, or 4m, or 3m, or 2m, or 1m, or 0.5m, or 0.2m.

[0078] The decarbonization absorption seawater supply equipment includes a water intake pipe for extracting seawater from the ocean below sea level. The depth of the inlet at the lower end of the water intake pipe relative to the actual sea level is not less than 0.5m, or not less than 1m, or not less than 3m, or not less than 5m, or not less than 10m, or not less than 15m, or not less than 20m, or not less than 30m, or not less than 50m, or not less than 100m, or not less than 200m, or not less than 300m, or not less than 500m, or not less than 1000m, or not less than 2000m.

[0079] The discharge equipment further comprises a drainage detection device for detecting the pH value of the seawater before discharge.

[0080] The decarbonized absorption seawater supply equipment also includes a device for adjusting the flow rate of the decarbonized absorption seawater so that the pH value of the seawater after decarbonization absorption meets the statutory discharge standards.

[0081] The discharge equipment further comprises a neutralizer for mixing the decarbonized and absorbed seawater with the neutralized seawater to form mixed seawater, so that the pH value is increased to meet the statutory discharge standards.

[0082] The system further comprises a neutralized seawater supply device for extracting seawater from the ocean to produce neutralized seawater.

[0083] The system further comprises a CCS ocean platform, and the pre-processor and / or decarbonization absorption tower and / or neutralizer are located on the CCS ocean platform to reduce the pumping height and power consumption of the seawater and reduce the onshore land area occupied by the CCS system.

[0084] The CCS offshore platform is selected from one or more of a floating offshore platform, a lifting offshore platform, and a fixed offshore platform.

[0085] The CCS offshore platform is a floating offshore platform that rises and falls with the tides of the sea surface, so as to reduce the additional pumping height and power consumption due to the tidal fluctuations. The platform is selected from one or more of a customized CCS floating dock and a conventional ocean vessel.

[0086] The CCS floating ocean platform is a CCS floating dock floating on the sea surface, rising and falling with the tide to overcome the power loss caused by the tidal range. The connection between the floating dock and the upper part of the ocean platform support frame fixed to the seabed at the bottom is vertical sliding and horizontal restriction.

[0087] The CCS floating dock is equipped with a limited anchoring device to limit the horizontal movement of the offshore platform from being pushed by wind and waves.

[0088] The CCS offshore platform is a lifting offshore platform that follows the tidal fluctuations of the sea surface to reduce the additional pumping height and power consumption due to the tidal fluctuations. It is selected from a customized height-adjustable offshore platform.

[0089] The height of the CCS lifting ocean platform is adjusted by the ocean platform support frame. The lower end of the support frame is fixed to the seabed and is equipped with hydraulic / pneumatic / mechanical devices to adjust the height. The lifting and lowering of the CCS ocean platform is automatically controlled according to the tidal law to overcome the power loss caused by the tidal difference.

[0090] The CCS offshore platform is a fixed offshore platform with a constant height relative to the seabed, and is selected from conventional offshore platforms.

[0091] The CCS fixed ocean platform has an underwater portion fixed to the seabed by a support frame, and an above-water portion at a fixed height. The elevation is designed based on the highest tide level, which is designed to occur once a year, once every five years, once every ten years, or once every 50 years.

[0092] The pre-processor is either installed on the same CCS marine platform as the decarbonization absorption tower, or deployed onshore together with the fossil energy system; the carbon-free power generation device is either integrated with the CCS system and deployed on the same CCS marine platform, and / or deployed at sea and / or onshore adjacent to the CCS system.

[0093] The system also includes a floating telescopic flue for transporting flue gas from the onshore fossil energy system to the CCS offshore platform.

[0094] The system also includes a device for measuring the amount of carbon capture and storage, for measuring the carbon dioxide equivalent (CO2e) captured and stored in fossil fuel flue gas, generating metering data, and transmitting the metering data to a carbon accounting system in real time or periodically.

[0095] The device for measuring the amount of carbon capture and storage is configured to detect the amount of carbon dioxide contained in the fossil fuel flue gas before contact with the decarbonized absorption seawater and the amount of carbon dioxide contained in the decarbonized gas after contact with the decarbonized absorption seawater, thereby measuring the carbon dioxide equivalent (CO2e) captured and stored in the fossil fuel flue gas.

[0096] The system also includes a carbon-free energy generation system.

[0097] The carbon-free energy power generation system drives a seawater pump to extract and pump the decarbonized absorbed seawater and / or neutralized seawater and / or pretreated seawater from the ocean.

[0098] The carbon-free energy power generation system includes one or more of wind energy, solar energy, wave energy, tidal energy, and nuclear energy; the carbon-free energy power generation system includes an energy storage device to ensure uninterrupted power supply.

[0099] The system also includes a direct atmospheric carbon capture and storage (DACCS) system.

[0100] The technical solution of the blue carbon power plant of the present invention is:

[0101] The blue carbon power plant includes a fossil energy system, which uses fossil fuel combustion to generate electricity and produces fossil fuel flue gas. It is characterized in that the blue carbon power plant also includes the carbon capture and storage (CCS) system of the present invention, which is used to decarbonize the fossil fuel flue gas.

[0102] Further technical solutions are:

[0103] The fossil energy system is selected from one or more of a coal-fired boiler steam turbine power generation system, a gas turbine power generation system, and a combined cycle gas and steam (CCGT) power generation system.

[0104] The blue carbon power plant also includes a flue gas bypass system, which is used to direct fossil fuel flue gas to the atmosphere when a risk accident occurs in the offshore carbon capture and storage system, thereby isolating the risk of marine accidents and ensuring the safe operation of the onshore fossil energy system.

[0105] The flue gas bypass system includes a fossil fuel flue gas bypass door and a flue gas bypass exhaust stack. The fossil fuel flue gas bypass door is configured to direct the fossil fuel flue gas to the flue gas bypass exhaust stack and then to the atmosphere when a risk accident occurs in the carbon capture and storage system.

[0106] The CCS system also includes a fixed ocean platform, the pre-processor is located on shore, and the decarbonization absorption tower and neutralizer are located on the fixed ocean platform; the pre-processor is configured to use cooling seawater at the end of the power plant turbine to wash the fossil fuel flue gas to achieve cooling and / or desulfurization pretreatment; the decarbonization absorption seawater and neutralization seawater are extracted from the ocean, and the energy required for extraction is provided by the power plant itself; at least 70% of the carbon dioxide in the fossil fuel flue gas is captured and stored.

[0107] The CCS system also includes a liftable ocean platform, on which the pre-processor, decarbonization absorption tower, and neutralizer are located; the pre-processor is configured to wash fossil fuel flue gas with pre-treated seawater to achieve cooling and / or desulfurization pre-treatment; the pre-treated seawater, decarbonization absorption seawater, and neutralization seawater are extracted from the ocean, and the energy required for extraction is provided by the power plant itself; at least 80% of the carbon dioxide in the fossil fuel flue gas is captured and stored.

[0108] The CCS system also includes a floating ocean platform and a carbon-free energy power generation system; the pre-processor, decarbonization absorption tower, and neutralizer are located on the CCS ocean platform; the pre-processor is configured to wash fossil fuel flue gas with pre-treated seawater to achieve cooling and / or desulfurization pre-treatment; the pre-treated seawater, decarbonization absorption seawater, and neutralization seawater are extracted from the ocean, and the energy required to extract seawater is provided by the carbon-free energy power generation system and / or the power station itself; at least 90% of the carbon dioxide in the fossil fuel flue gas is captured and stored.

[0109] The CCS system also includes a floating ocean platform, a carbon-free energy power generation system, and a direct air carbon capture and storage (DACCS) system; the pre-processor, decarbonization absorption tower, and neutralizer are located on the CCS ocean platform; the CCS ocean platform is configured as a floating and / or liftable ocean platform that rises and falls with the tide; the pre-treated seawater, decarbonization absorption seawater, and neutralization seawater are extracted from the ocean, and the energy required for extracting seawater is mainly provided by the carbon-free energy power generation system; at least 95%, or 90%, or 85%, or 80%, or 75%, or 70%, 60%, or 50% of the carbon dioxide in fossil fuel flue gas is captured and stored; the direct air carbon capture and storage (DACCS) system directly captures and stores carbon dioxide from the atmosphere, and the amount of carbon dioxide captured and stored is equal to the amount of carbon dioxide in the decarbonized gas discharged into the atmosphere, and the required electricity comes from the carbon-free energy power generation system.

[0110] The clean energy products produced by the fossil energy conversion system are transported externally, and the energy products include but are not limited to electrical energy and / or thermal energy and / or mechanical energy and / or hydrogen energy.

[0111] The carbon-free energy power generation system transmits carbon-free energy products to the outside through the carbon-free energy product output channel, including but not limited to electrical energy and / or thermal energy and / or mechanical energy and / or hydrogen energy and / or other energy products.

[0112] Technical principles and effects of the present invention:

[0113] The technical solution of the present invention only uses seawater to absorb and capture CO2 and convert it into bicarbonate ions (HCO3 — ) - Carbon is permanently stored in the ocean in its natural form in seawater. The principles of seawater absorption carbon capture technology and bicarbonate ion mode ocean carbon sequestration technology involved are both based on the following marine chemical reaction formula.

[0114] The chemical reaction formula of CO2 dissolving in seawater is:

[0115] First, the principles of marine chemistry tell us that in the normal pH range of 7.8 to 8.3 in seawater, and the pH range of 6 to 9 required by marine environmental protection regulations, the above chemical reaction proceeds to the right, and the product is bicarbonate ions (HCO3 - )——the natural form and main existence mode of carbon in seawater. The technical solution of the present invention is designed in accordance with the statutory discharge standards of the specific implementation area. For example, the pH ≥ 6.5 in the IMO MEPC 259 (68) rule under the United Nations MARPOL Convention, or the pH ≥ 6.0 in the EPA VGP 2013 rule governing North America, are determined as the pH limit of the seawater discharged after decarbonization and absorption in the present invention. Therefore, what actually enters and is stored in the seawater is the natural form of bicarbonate ions (HCO3 - ), that is, the present invention is "bicarbonate ion (HCO3 - Ocean Storage of HCO3 - ), rather than the "Ocean Storage of CO2" that has been subject to public scrutiny and regulatory restrictions. Furthermore, the technical solution of the present invention is not only legally binding but also has the environmental and climatic benefits of being friendly to the marine ecosystem and permanently storing ocean carbon.

[0116] Secondly, the rate and amount of CO2 dissolving in seawater are negatively correlated with and highly sensitive to the temperature and acidity of the seawater: the lower the seawater temperature and acidity, the higher the dissolution rate and amount of CO2, and the greater the corresponding carbon capture rate, i.e., the decarbonization depth. To this end, the technical solution of the present invention, on the one hand, uses seawater to wash and pre-treat the high-temperature, high-sulfur flue gas produced by the combustion of fossil fuels to turn it into a low-temperature, low-sulfur gas, thereby significantly reducing the heat and acidity of the flue gas brought into the decarbonization absorption seawater. On the other hand, fresh seawater with a lower water temperature (at least 8 to 9°C lower than the cooling water temperature of the power plant) is extracted from the sea as the decarbonization absorption seawater, thereby lowering the seawater temperature and acidity when washing, dissolving, and capturing CO2 in the decarbonization absorption tower, thereby achieving the technical effect of further improving the carbon capture rate and increasing the decarbonization depth.

[0117] Furthermore, the present invention uses decarbonized seawater to wash and capture CO2 in flue gas, and the amount of carbon captured is positively correlated with the flow rate of decarbonized seawater. Therefore, the upper limit of the capture amount and decarbonization depth depends on the affordable total energy consumption of decarbonized seawater, which is equal to the product of the total flow rate of decarbonized seawater and the seawater lifting elevation. Therefore, the present invention adopts a large-flow, low-lift pumping method to arrange processes such as decarbonization absorption towers that require a large amount of water on a CCS marine platform as close to the sea surface as possible. Compared with arranging them onshore power plant sites, this significantly reduces the elevation and power consumption required for pumping seawater. In addition, the CCS floating marine platform rises and falls with the tide, and the seawater lifting elevation can always be at the optimal value, eliminating the additional energy loss caused by reserving elevation for the tidal drop (generally several meters to more than ten meters). Therefore, the technical effect of significantly reducing the cost of decarbonization is achieved. Not only that, it also solves the problem that existing power plants cannot deploy CCS due to lack of land space.

[0118] In addition, the present invention adopts a deep water extraction method to extract decarbonized absorbing seawater from the ocean, aiming to extract deeper and lower temperature decarbonized absorbing seawater to obtain a higher carbon capture rate: for example, in some sea areas, the seawater temperature drops by about 0.5°C for every 100m of depth. Based on the principle that there is no potential energy loss when the medium in a homogeneous and homogeneous (fluid) environment is vertically lifted, increasing the water extraction depth has little effect on the power consumption of the water pump, that is, the cost, but is very helpful in increasing the solubility of CO2, that is, the carbon capture rate.

[0119] The overall technical effect of the technical solution of the present invention is to achieve the green and low-carbon transformation of fossil energy such as gas, oil and coal-fired power plants at extremely low cost, and integrate them with renewable energy for win-win development, creating the necessary conditions for the large-scale utilization of marine natural carbon sink power stations required to achieve the 2050 net zero carbon emission climate goal. BRIEF DESCRIPTION OF THE DRAWINGS

[0120] FIG1 is a schematic diagram of an embodiment of the net zero carbon fossil energy production method of the present invention.

[0121] FIG2 is a schematic diagram of an embodiment of a low-carbon emission energy production system for a coal-fired power plant according to the present invention, which is characterized in that the pre-processor is deployed onshore, the decarbonization absorption tower and the neutralizer are deployed offshore, and the CCS seawater pump is driven by power from the power plant.

[0122] FIG3 is a schematic diagram of an embodiment of a low-carbon emission energy production system of a gas-steam combined cycle power plant according to the present invention, which is characterized in that a pre-processor, a decarbonization absorption tower, and a neutralizer are deployed on a floating CCS offshore platform, and the power plant electricity is used to drive the CCS seawater pump.

[0123] FIG4 is a schematic diagram of an embodiment of a near-zero carbon emission energy production system of a gas-steam combined cycle power plant according to the present invention, which is characterized in that a pre-processor, a decarbonization absorption tower, and a neutralizer are deployed on a floating CCS ocean platform, and carbon-free energy is used to drive the CCS seawater pump.

[0124] Figure 5 is a schematic diagram of an embodiment of a net zero carbon emission energy production system for a fossil fuel power plant of the present invention, which is characterized in that a pre-processor, a decarbonization absorption tower, and a neutralizer are deployed on a floating CCS ocean platform, and carbon-free energy is used to drive the CCS seawater pump and the direct air carbon capture and storage DACCS system.

[0125] FIG6 is a schematic diagram of the decarbonization absorption tower structure of the present invention, the elevation of its water distributor, and the elevation of the neutralizer liquid level.

[0126] The names of the objects marked with the figure numbers in the accompanying drawings are: 1—fossil energy system, 1.1—combustion device, 1.2—smoke exhaust duct, 1.3—flue gas bypass door, 1.4—flue gas bypass exhaust pipe, 1.5—fossil energy conversion device, 1.6—fossil energy power generation device, 1.7—clean energy product output channel, 2—CCS system, 2.1—CCS offshore platform, 2.1-1—CCS fixed offshore platform, 2.1-2—CCS lifting offshore platform, 2.1-3—CCS floating Offshore platform (floating dock), 2.2—offshore chimney and support, 2.3—pre-processor, 2.4—pre-processed seawater pump, 2.5—pre-processed seawater pump intake pipe, 2.6—pre-processed seawater delivery pipe, 2.7—pre-processed water standard discharge pipe, 2.8—pre-processed seawater treatment tank, 2.9—packing layer, 2.10—water distributor, 2.11—water distributor elevation, 2.12—decarbonization absorption tower, 2.13—decarbonization absorption seawater pump, 214— Decarbonization absorption seawater pump intake pipe, 2.15—Offshore platform support frame, 2.16—Decarbonization absorption seawater delivery pipe, 2.17—Decarbonization absorption tower drain pipe, 2.18—Neutralizer, 2.19—Neutralization seawater pump, 2.20—Neutralization seawater pump intake pipe, 2.21—Neutralizer liquid level, 2.22—Neutralization seawater pipe, 2.23—pH detection controller, 2.24—Decarbonization flue gas pipeline, 2.25—Exhaust stack, 2.26—Standard Seawater discharge pipe, 3—CO2e metering unit / device, 3.1—CO2e data channel, 3.2—CCS detection sampling data channel, 4—Carbon-free energy power generation system, 4.1—Wind power station, 4.2—Wind turbine, 4.3—Energy storage device, 4.4—Power line, 4.5—Photovoltaic power station, 4.6—Wave power generator, 4.7—Carbon-free energy product output channel, 5—Direct Air Carbon Capture and Storage (DACCS) system. DETAILED DESCRIPTION

[0127] Example 1: A basic embodiment of the net zero carbon fossil energy production method of the present invention, as shown in FIG1 , includes the following steps:

[0128] 1) Burning fossil fuels to produce energy and fossil fuel flue gas;

[0129] 2) pre-treating the fossil fuel flue gas by cooling and / or desulfurizing to generate pre-treated flue gas;

[0130] 3) using decarbonized absorption seawater to capture carbon from the pretreated flue gas, thereby generating decarbonized absorption seawater and decarbonized gas;

[0131] 4) discharging the decarbonized gas into the atmosphere;

[0132] 5) Injecting decarbonized seawater into the ocean for carbon sequestration;

[0133] Example 2: An example based on Example 1, comprising the following steps:

[0134] 1) Burning fossil fuels to generate energy and emitting high-temperature flue gas containing carbon (CO2); cooling and / or desulfurizing the high-temperature flue gas to become low-temperature, low-sulfur, carbon-containing gas before introducing it into a decarbonization absorption tower;

[0135] 2) extracting decarbonized absorption seawater from the ocean using a seawater pump and introducing it into a decarbonization absorption tower to wash the carbon-containing gas to capture CO2 in the carbon-containing gas, thereby generating decarbonized gas and decarbonized absorption seawater; the decarbonized gas is discharged into the atmosphere;

[0136] 3) Adjusting the pH value of the decarbonized seawater to meet the discharge standards allowed by regulations and becoming qualified discharge seawater. At this time, the CO2 dissolved in the decarbonized seawater has been converted into incremental bicarbonate ions (HCO3 — );

[0137] 4) The discharged seawater that meets the standards is injected into the ocean water body below the sea surface by gravity through a pipeline to achieve bicarbonate ion mode ocean carbon sequestration;

[0138] 5) Detecting and measuring the carbon dioxide equivalent (CO2e) captured and stored in the ocean.

[0139] The decarbonized and absorbed seawater and / or neutralized seawater is extracted from the ocean using a high-flow, low-lift pumping method, and the required electrical energy comes from fossil energy and / or carbon-free energy.

[0140] The decarbonized seawater is extracted from the ocean using a deep water extraction method.

[0141] The fossil fuels include natural gas, oil, and coal.

[0142] The clean energy products produced by the fossil energy conversion system are transported externally, and the energy products include but are not limited to electrical energy and / or thermal energy and / or mechanical energy and / or hydrogen energy.

[0143] Example 3: Multiple groups of examples based on Example 1, as shown in Figures 1 to 6:

[0144] The combustion of the fossil fuel relies on air to assist combustion, and the pressure of the high-temperature carbon-containing flue gas generated is normal pressure, i.e., atmospheric pressure; the pretreatment, in one embodiment, is to use pretreated washing seawater to wash the high-temperature carbon-containing (CO2) flue gas to achieve cooling and / or desulfurization, and in another embodiment, it is to use the original flue gas desulfurization (FGD) process of the fossil energy system instead; the pretreated washing seawater, in one embodiment, is extracted from the sea, and in another embodiment, it is to use cooling seawater from a power plant or other process drainage. The temperature of the cooling seawater from the power plant is generally 8 to 9°C higher than the temperature of the seawater directly taken from the sea. Therefore, the cooling and / or desulfurization effect of the pretreated washing seawater directly extracted from the sea is better, which is conducive to improving the decarbonization absorption effect and carbon capture rate.

[0145] The temperature and sulfur content parameters of the low-temperature, low-sulfur carbon-containing gas after pretreatment and before decarbonization and absorption are, in one embodiment, no higher than 50°C, no higher than 30°C, no higher than 20°C, no higher than 10°C, or no higher than 5°C compared to the temperature of the seawater for decarbonization and absorption; in another embodiment, the volume content of SO2 in the carbon-containing gas is less than 100ppm, less than 80ppm, or less than 30ppm. The temperature and sulfur content parameters of the low-temperature, low-sulfur carbon-containing gas before decarbonization and absorption after pretreatment are adjusted by varying the flow rate of pretreatment scrubbing seawater.

[0146] The internal pressure of the decarbonization absorption tower is normal pressure (atmospheric pressure) and is connected to the outside atmosphere through an exhaust pipe; the decarbonization absorption seawater is introduced into the tower from the top of the decarbonization absorption tower and falls downward by its own weight to contact the carbon-containing gas introduced into the tower, thereby washing and capturing CO2;

[0147] One embodiment uses a packed absorption tower, so that the decarbonized absorption seawater contacts the carbon-containing gas through the packing layer to obtain a larger gas-liquid contact area, thereby achieving a better CO2 washing, dissolution and capture effect.

[0148] The pH value of the decarbonized seawater is adjusted to meet the legally permitted discharge standard, which is to meet the legally permitted discharge standard of the area where the drainage is located, such as the pH ≥ 6.5 in the IMO MEPC 259 (68) rule under the United Nations MARPOL Convention, or the pH ≥ 6.0 in the EPA VGP 2013 rule governing North America, including the specific provisions of the discharge mixing zone designated by the local environmental law enforcement agency; at this time, the CO2 captured by washing in the discharged seawater has been converted into incremental bicarbonate ions (HCO3 — ) - the natural and main form of carbon in the ocean, the step of injecting the subsurface ocean water is to achieve a natural and permanent bicarbonate ion (HCO3 - ) Model ocean carbon sequestration.

[0149] The method for adjusting the pH value is to adjust the ratio of the decarbonized absorption seawater flow rate to the carbon-containing gas flow rate, and / or mix the decarbonized absorption seawater with the neutralized seawater in a neutralizer and adjust the mixing ratio; to this end, one embodiment sets a pH detection controller in the power supply control circuit of the decarbonized absorption seawater pump and the neutralized seawater pump; the neutralized seawater is extracted from the ocean.

[0150] The detection and measurement of the carbon dioxide equivalent (CO2e) captured and used to achieve ocean carbon sequestration is to detect and measure the difference in CO2 content between 1) the carbon-containing high-temperature flue gas emitted by the combustion of the fossil fuel and 2) the decarbonized gas emitted by the decarbonization absorption tower, and transmit the measured CO2e (carbon dioxide equivalent) data to a designated carbon accounting system.

[0151] The gas CO2 content detection and measurement technology is relatively mature, and the relevant CO2e detection meter and data processor can be selected from commercially available flue gas composition measuring instruments.

[0152] The high-flow, low-lift pumping method reduces the pumping altitude of the seawater required by the decarbonization absorption tower 2.12, neutralizer 2.18, and pre-processor 2.3 to reduce potential energy loss. This requires both lowering the elevation of the device's foundation relative to sea level to reduce foundation potential energy loss and lowering the device's operating altitude to reduce operating potential energy loss. One embodiment of reducing foundation potential energy loss is to perform one or more of the pretreatment, decarbonization absorption, and neutralization steps on the CCS offshore platform 2.1. Because the CCS offshore platform 2.1 is designed to be deployed offshore, close to the sea surface, the equipment deployed thereon has a significantly lower base elevation than the onshore power plant deployment described in the embodiment.

[0153] One group of embodiments for reducing the working potential energy loss, wherein the height of the horizontal center line of the water distributor of the decarbonization absorption tower relative to the actual sea level is not higher than 50m, or 30m, or 25m, or 20m, or 15m, or 10m, or 9m, or 8m, or 7m, or 6m, or 5m, or 4m, or 3m, or 2m, or 1m, or 0.5m; another group of embodiments for reducing the working potential energy loss, wherein the height of the liquid level of the neutralizer relative to the actual sea level is not higher than 10m, or 9m, or 8m, or 7m, or 6m, or 5m, or 4m, or 3m, or 2m, or 1m, or 0.5m, or 0.2m.

[0154] The extraction of decarbonized absorption seawater from the ocean adopts a deep water extraction method, aiming to extract deeper and lower-temperature decarbonized absorption seawater to obtain a higher carbon capture rate. In some sea areas, the water temperature decreases by about 0.5°C for every 100m increase in depth. This is very helpful for increasing the solubility of CO2 and the carbon capture rate, while the cost increases very little, because the power consumption of the water pump is sensitive to the pumping head but not to the water extraction depth. To this end, a group of embodiments respectively extract seawater at a depth of not less than 0.5m, or not less than 1m, or not less than 3m, or not less than 5m, or not less than 10m, or not less than 15m, or not less than 20m, or not less than 30m, or not less than 50m, or not less than 100m, or not less than 200m, or not less than 300m, or not less than 500m, or not less than 1000m, or not less than 2000m below the actual sea level.

[0155] The power supply for the seawater pump that extracts decarbonized and absorbed seawater and / or neutralizes seawater and / or pre-treats and washes seawater from the ocean: one group of embodiments comes from a carbon-free energy generation system 4, which are carbon-free energy systems such as wind energy, solar energy, wave energy, tidal energy, and nuclear energy, including carbon-free energy systems that use energy storage methods to ensure uninterrupted power supply; another group of embodiments is provided by the fossil energy system 1; and another group of embodiments is provided by the carbon-free energy generation system 4 and the fossil energy system 1.

[0156] Example 4: A carbon capture and storage (CCS) system embodiment for implementing the method of the present invention, the system comprising:

[0157] A pre-processor, which performs cooling and / or desulfurization pre-treatment on the fossil fuel flue gas to generate pre-treated flue gas;

[0158] a decarbonization absorption tower, which uses decarbonization absorption seawater to wash the pretreated flue gas to absorb and capture carbon dioxide, generating decarbonization absorption seawater and decarbonization gas, and discharging the decarbonization gas into the atmosphere;

[0159] Decarbonized absorption seawater supply equipment, used to pump seawater extracted from the ocean to the decarbonized absorption tower to become decarbonized absorption seawater;

[0160] Discharge equipment is used to discharge the decarbonized and absorbed seawater into the ocean for carbon sequestration.

[0161] The pre-processor / decarbonization absorption tower / discharge equipment are all operated at normal pressure (atmospheric pressure), and the drainage of the equipment is configured to flow into the next process by relying on its own weight, and / or be injected into the ocean.

[0162] Example 5: An embodiment of a device for implementing the method of the present invention is shown in Figures 1 to 6:

[0163] The device provides a fossil energy system 1, a CCS system 2, a carbon-free energy power generation system 4 and a direct air carbon capture and storage (DACCS) system 5 configured when near-zero / net-zero carbon emissions are required; the fossil energy system 1 includes a combustion device 1.1, a fossil energy conversion device 1.5, and a fossil energy power generation device 1.6, which transports clean energy products to the outside through a clean energy product output channel 1.7 and discharges carbon-containing high-temperature flue gas through a flue 1.2; the CCS system 2 includes a CCS offshore platform 2.1 for carrying the CCS process device, and an offshore flue 2.2 for connecting the fossil energy system 1 and the CCS system. System 2, pre-processor 2.3 is used to process the carbon-containing high-temperature flue gas into low-temperature, low-sulfur carbon-containing gas; decarbonization absorption tower 2.12 is installed on the CCS ocean platform 2.1, and is used to make the low-temperature, low-sulfur carbon-containing gas fully contact with decarbonization absorption seawater to perform seawater absorption carbon capture, decarbonization absorption seawater supply equipment includes decarbonization absorption seawater pump 2.13, decarbonization absorption seawater pump water pipe 2.14, decarbonization absorption seawater delivery pipe 2.16, etc., and neutralization seawater supply equipment includes neutralization seawater pump 2.19, neutralization seawater pump water pipe 2.20, neutralization seawater pipe 2.22, etc., decarbonization absorption seawater pump 2.13 supplies decarbonization absorption seawater to decarbonization absorption tower 2.1 2 provides decarbonized absorption seawater, and the neutralizer 2.18 is installed on the CCS marine platform 2.1, which is used to mix and neutralize the decarbonized absorption seawater discharged from the decarbonization absorption tower 2.12 with the neutralized seawater provided by the neutralization seawater pump 2.19 to produce qualified discharge seawater that meets the discharge standards allowed by regulations; the qualified discharge seawater is discharged into the seawater below the sea surface by its own weight through the qualified seawater discharge pipe 2.26 to achieve bicarbonate ion mode marine carbon sequestration; the discharge pH detection controller 2.23 (discharge detection device) is used to detect and control the pH value of the qualified discharge seawater; the CO2e metering unit / device 3 (for measuring The equipment for measuring carbon capture and storage is used to detect and measure the carbon dioxide equivalent (CO2e) of the seawater absorption carbon capture and the bicarbonate ion mode ocean carbon sequestration; the exhaust chimney 2.25 is used to connect the decarbonization absorption tower 2.12 to the atmosphere so that the decarbonized gas can be discharged into the atmosphere; the carbon-free energy power generation system 4, and / or the fossil energy power generation device 1.6, are used to supply power to the CCS system 2; the carbon-free energy power generation system 4 transmits carbon-free energy products to the outside through the carbon-free energy product output channel 4.7 as needed; the direct air carbon capture and storage (DACCS) system 5 is used to directly capture carbon dioxide from the air and store it.

[0164] Example 6: Multiple groups of examples based on Example 3, as shown in Figures 1 to 6:

[0165] In one embodiment, the combustion device 1.1 is a boiler, a combined cycle gas and steam turbine (CCGT), a waste heat boiler, and an internal combustion engine.

[0166] Multiple groups of CCS offshore platforms with reduced seawater pumping height are provided as embodiments. The CCS offshore platforms 2.1 include a CCS fixed offshore platform 2.1-1, a CCS lift offshore platform 2.1-2, and a CCS floating offshore platform, namely a CCS floating dock 2.1-3.

[0167] One embodiment comprises a CCS fixed offshore platform 2.1-1, wherein the underwater portion is fixed to the seabed via a support frame, and the above-water portion is fixed at a fixed height. The elevation of the installation foundation of the decarbonization absorber 2.12, the neutralizer 2.18, and the pre-processor 2.3 is designed based on the highest tide level, which is designed for annual, five-year, ten-year, and fifty-year recurrences. The embodiment designed for the annual highest tide level is more cost-effective.

[0168] For water-using equipment at a fixed altitude, the pumping head must be designed for the highest tide level. This results in potential energy loss during low tides, which is also known as power loss. The tidal range in the same sea area varies from time to time, typically by several meters. For pumping large volumes of water for CCS applications, even a tidal range of 0.5 or 1 meter can result in significant power loss.

[0169] One embodiment of overcoming power loss caused by tidal range uses a CCS to raise and lower an offshore platform 2.1-2, as shown in Figure 3. The offshore platform 2.1 is fixedly connected to the upper end of an offshore platform support frame 2.15. The height of the offshore platform 2.1 is adjusted by the offshore platform support frame 2.15. The lower end of the support frame 2.15 is fixed to the seabed and equipped with hydraulic / pneumatic / mechanical devices to adjust the height. The CCS offshore platform 2.1 is automatically raised and lowered according to the tidal pattern.

[0170] Another embodiment for overcoming power loss caused by tidal range uses a CCS floating ocean platform, as shown in Figure 3. The ocean platform 2.1 is a CCS floating dock 2.1-3 that floats on the sea surface, rising and falling with the tide. In one embodiment, the floating dock 2.1-3 is connected to the upper portion of an ocean platform support frame 2.15, whose lower portion is fixed to the seabed, by vertical sliding and horizontal restriction. In another embodiment, the CCS floating dock 2.1-3 is equipped with a limited anchoring device to limit the horizontal movement range of the ocean platform from excessive force due to wind and waves; the limited anchoring device is selected from existing marine engineering equipment, such as a series of pontoons. In another embodiment, the CCS ocean platform is replaced by a conventional ocean vessel; in yet another embodiment, it is replaced by a self-sustaining snorkeling ocean platform.

[0171] In one set of embodiments, the energy products transported through the clean energy product output channel 1.7 and / or the carbon-free energy products transported through the carbon-free energy product output channel 4.7 are respectively electric energy, thermal energy, mechanical energy, hydrogen energy, and other energy products.

[0172] In one embodiment, the pre-processor 2.3 is installed on the same CCS ocean platform 2.1 as the decarbonization absorption tower 2.12, or is deployed onshore together with the fossil energy system 1;

[0173] In one set of embodiments, the carbon-free energy power generation system 4 is integrated with the CCS system 2 and deployed on the same CCS marine platform 2.1, and / or deployed at sea and / or on shore near the CCS system 2.

[0174] The decarbonized absorption seawater is introduced from the upper exterior of the decarbonization absorption tower, distributed along the tower's cross-section through a water distributor within the tower, and falls downward by gravity. It flows through the tower's packing layer, exposing the introduced carbon-containing gas over a large area to dissolve and capture CO2. The decarbonization absorption tower utilizes packing to increase the gas-liquid contact area. The packing is made of materials that can withstand high accident temperatures, including metals, ceramics, and polymers.

[0175] The offshore flue 2.2 is connected to the onshore combustion device 1.1, and guides high-temperature, carbon-containing flue gas to the offshore CCS offshore platform for pretreatment; or guides the pretreated flue gas from the combustion of fossil fuels onshore to the CCS offshore platform for post-treatment such as decarbonization and absorption. The offshore flue 2.2 is made of metal and / or polymer and / or other materials, and its telescopic length and bending angle can be changed within a wide range to adapt to the swaying of the CCS offshore platform with the rise and fall of tides and the fluctuations of sea waves, and to maintain the flue gas transportation between the onshore combustion facility and the CCS offshore platform. In cases where the CCS offshore platform 2.1 is far from the shore, intermediate support is provided for the offshore flue 2.2, and this support consists of a support frame fixed to the seabed, and / or a floating bridge and / or a pontoon.

[0176] The temperature of the decarbonized absorption seawater when used for absorption is no higher than the natural temperature of the seawater at the extraction location by 5°C, no higher than 4°C, no higher than 3°C, no higher than 2°C, or no higher than 1°C. The temperature of the neutralization seawater when used for neutralization is no higher than the natural temperature of the seawater at the extraction location by 10°C, no higher than 5°C, no higher than 3°C, or no higher than 1°C.

[0177] The lower end outlet of the standard seawater discharge pipe 2.26 is located at a depth below sea level of not less than 0.5m, not less than 1m, not less than 3m, not less than 5m, not less than 10m, not less than 15m, not less than 20m, not less than 30m, not less than 50m, not less than 100m, not less than 200m, not less than 300m, and not less than 500m.

[0178] Example 7: An example of a blue carbon power plant implementing the method and system solution of the present invention is shown in Figures 1 to 6:

[0179] The power station provides a fossil energy system 1, a CCS system 2, a CO2e metering unit 3, a carbon-free energy power generation system 4 and a direct air carbon capture and storage (DACCS) system 5 configured as needed for near-zero / net-zero carbon emissions; the fossil energy system 1, a group of embodiments are a conventional coal-fired boiler steam turbine power generation process, a gas turbine power generation process, and a gas-steam combined cycle power generation process (CCGT), which burns fossil fuels to generate heat energy to drive the steam turbine and generator to generate electricity, and at the same time produces carbon-containing high-temperature flue gas; the CCS system 2 includes a pre-processor 2.3, a decarbonization absorption tower 2.12, and a neutralizer 2.18, which extracts seawater from the sea to wash the flue gas for absorption carbon capture, and bicarbonate ion mode marine carbon sequestration in accordance with regulations; the CO2e metering unit 3 detects and measures the carbon dioxide equivalent captured and marine carbon sequestered.

[0180] In one embodiment, the power plant is a low-carbon emission power plant with a carbon capture and storage rate, i.e., a decarbonization depth, of >70%. The pre-processor 2.3 is installed onshore, and the pre-treated washing seawater utilizes the cooling seawater at the end of the power plant's steam turbine. The pre-treated seawater pump 2.4, i.e., the power plant's cooling water seawater pump (commonly known as a circulating water pump), processes the pre-treated washing seawater to treat high-temperature flue gas, and then is treated in a pre-treated seawater treatment tank 2.8 to meet regulatory emission standards before being discharged into the ocean. The CCS offshore platform 2.1 on which the decarbonization absorber 2.12 and the neutralizer 2.18 are installed is a fixed offshore platform. The seawater required by the decarbonization absorber 2.12 and the neutralizer 2.18 is pumped using a high-volume, low-lift pumping method, and the required electricity is derived from the fossil energy power plant's own electricity.

[0181] The power station described in one embodiment is a near-zero carbon emission power station with a carbon capture and storage rate, i.e., a decarbonization depth of >90%. The CCS ocean platform 2.1 on which the pre-processor 2.3, the decarbonization absorption tower 2.12, and the neutralizer 2.18 are installed is a lift-type, i.e., a height-adjustable CCS ocean platform; the seawater required for the pre-processor 2.3, the decarbonization absorption tower 2.12, and the neutralizer 2.18 is extracted from the ocean and a high-volume, low-lift pumping method is adopted. The required electricity mainly comes from the carbon-free energy power generation system 4; the decarbonization absorption tower 2.12 is installed. The seawater to be decarbonized and absorbed is extracted from the ocean, that is, the seawater is extracted from a depth of not less than 0.5m, or not less than 1m, or not less than 3m, or not less than 5m, or not less than 10m, or not less than 15m, or not less than 20m, or not less than 30m, or not less than 50m, or not less than 100m, or not less than 200m, or not less than 300m, or not less than 500m, or not less than 1000m, or not less than 2000m below the actual sea level; the pre-processor washing seawater discharge is designed to directly meet the standards and be discharged into the sea.

[0182] In another embodiment, the power station is a net zero carbon emission power station, as shown in Figure 5, the carbon capture and storage rate, that is, the decarbonization depth is about 100%; the CCS marine platform 2.1 on which the pre-processor 2.3, the decarbonization absorption tower 2.12 and the neutralizer 2.18 are installed adopts a CCS floating dock; the seawater required by the pre-processor 2.3, the decarbonization absorption tower 2.12 and the neutralizer 2.18 is pumped by a large water volume and low lift method, and the required electricity comes from the carbon-free energy power generation system 4; the decarbonization absorption tower 2.12 is pumped from the power station No less than 95%, or no less than 90%, or no less than 85%, or no less than 80%, or no less than 75%, or no less than 70%, or no less than 60%, or no less than 50% of CO2 is captured from the carbon-containing flue gas of fossil fuels; the amount of CO2 directly captured and stored from the atmosphere by the direct air carbon capture and storage (DACCS) system (5) is equal to the amount of CO2 emitted to the atmosphere by the remaining CO2 in the decarbonized gas after the decarbonization absorption and capture, and the required electricity comes from the carbon-free energy power generation system 4.

[0183] In another embodiment, the fossil energy system 1 provides a flue gas bypass system, including a fossil fuel flue gas bypass door 1.3 and a flue gas bypass exhaust chimney 1.4. The fossil fuel flue gas bypass door 1.3 is connected between the onshore fossil fuel combustion device 1 and the inlet of the offshore flue 2.2. When a risk accident occurs in the CCS process system floating on the sea surface, the fossil fuel flue gas is directed to the flue gas bypass exhaust chimney 1.4, so as to decouple the CCS process system, isolate the risk of marine accidents, and ensure the safe operation of the onshore fossil energy system.

[0184] Example 8: A set of examples of the low-carbon transformation of a coastal coal-fired power plant group into a blue carbon power plant, as shown in Figures 1 to 5: The power plant group was originally a coal-fired power plant group operating in the existing power grid, with a total installed capacity of 5.28GW, including 8 sets of 660MW ultra-supercritical generating units. The total CO2 emissions of the power plant's coal-fired boilers are about 20Mt / yr, the exhaust gas temperature is about 128°C, the SO2 volume content in the exhaust gas varies depending on the coal quality, and CO2 is about 13% to 15% of the exhaust gas volume; the original flue gas desulfurization (FGD) is 8 sets of limestone / gypsum wet desulfurization process; the evaporation capacity of a single boiler is 2,078t / h, and the flue gas volume of a single boiler is 1,900,000Nm 3 / h; the zero-meter layer of the power plant is 30m above sea level.

[0185] The first embodiment is an embodiment of the transformation of a low-carbon emission fossil energy production device. The transformation process is as follows: 1) the original limestone / gypsum wet flue gas desulfurization (FGD) system of the power plant is used as a substitute pre-processor 2.3 to treat the flue gas discharged from the power plant into a CO2-containing gas flow with a temperature of about 60°C and a SO2 concentration of less than 80 ppm; 2) the original FGD flue gas bypass gate of the power plant is transformed into a flue gas bypass gate 1.3 that matches the process of the present invention, and the original exhaust stack of the power plant is replaced with a flue gas bypass exhaust stack 1.4 that matches the process of the present invention; 3) offline construction 4) During the planned maintenance outage of the power plant, the CCS offshore platform 2.1 and its CCS system will be connected, and / or the existing flue gas bypass gate 1.3 will be used to switch to the CCS system without shutting down the power plant. The CCS system will be powered by the power plant's electricity consumption. After this implementation, the coal-fired power plant will achieve low carbon emissions, with a carbon capture and storage rate greater than 75% and a total CCS volume of 15 Mt / yr.

[0186] The second embodiment is developed on the basis of the first embodiment, and is an embodiment of the transformation of a near-zero carbon emission fossil energy production device. The transformation process is as follows: 1) a dedicated seawater washing pre-processor 2.3 is set on the CCS lifting ocean platform 2.1-2, and fresh seawater is extracted nearby on the CCS ocean platform 2.1 for pre-processing seawater washing, so the temperature of the flue gas after pretreatment is significantly lower than that of the first embodiment; 2) a decarbonization absorption seawater pump 2.13 is set on the lifting CCS ocean platform 2.1-2 to extract the decarbonization absorption seawater. The lower intake of water pipe 2.14 is located at a depth of 300 meters below the sea surface, allowing decarbonization and absorption to occur at relatively low temperatures, thereby increasing the carbon capture rate and reducing electricity consumption. 3) New offshore and / or onshore wind power stations and / or photovoltaic power stations will be constructed near the power station as carbon-free energy generation systems to provide all the required electricity to the CCS system, ensuring that the entire carbon capture and storage process consumes no fossil energy and has a zero carbon footprint. After implementation, the coal-fired power station will achieve near-zero carbon emissions, a carbon capture and storage rate of 95%, and a total CCS volume of 19 Mt / yr.

[0187] The overall effect of this embodiment is:

[0188] 1) After the original FGD process system was shut down and dismantled, the hundreds of thousands of tons of ore (desulfurizer) previously consumed annually from a mining area hundreds of kilometers away, and the millions of tons of fresh water (desulfurizer solvent) consumed annually from seawater desalination, the large amount of carbon emissions generated by these energy resource consumption processes, and their economic costs were all reduced to zero.

[0189] 2) Since the additional cost of deep decarbonization in this embodiment is close to the original FGD operating cost, the total power generation cost of the power plant after adding the deep decarbonization function increases very little, or may even not increase at all.

[0190] 3) All captured CO2 is converted into bicarbonate ions, the natural form of carbon in seawater, and permanently sealed in the carbon sink of the marine ecosystem. This not only complies with current international conventions and national regulations, but also ensures a friendly marine ecological environment.

[0191] Example 9: Another set of examples for the low-carbon transformation of a coastal coal-fired power plant group, as shown in Figures 1 to 5: The power plant group is a coal-fired power plant group operating in the existing power grid, with a total installed capacity of 5.28GW, including 8 sets of 660MW ultra-supercritical generating units. The total CO2 emissions from the power plant's coal-fired boilers are approximately 20Mt / yr, the exhaust gas temperature is approximately 128°C, the SO2 volume content in the exhaust gas varies depending on the coal quality and ranges from 300 to 800ppm, and CO2 accounts for approximately 13 to 15% of the exhaust gas volume; the original flue gas desulfurization (FGD) is 8 sets of seawater desulfurization processes, using power plant turbine cooling water as a desulfurization washing agent in the desulfurization process; the evaporation capacity of a single boiler is 2,075t / h, and the flue gas volume of a single boiler is 1,905,000Nm 3 / h; the zero-meter layer of the power plant is 33m above sea level.

[0192] The first embodiment is an embodiment of the transformation of a low-carbon emission fossil energy production device, and the implementation process is as follows: 1) the original seawater flue gas desulfurization (FGD) system of the power plant is used as a substitute pre-processor 2.3 to treat the flue gas discharged from the power plant into a CO2-containing gas flow with a temperature of about 40°C and a SO2 concentration of less than 80 ppm; steps 2), 3), and 4) are the same as steps 2), 3), and 4) of the first implementation process of Example 6. After implementation, the coal-fired power plant achieves low carbon emissions, its carbon capture and storage rate is greater than 80%, and the total CCS amount is about 16Mt / yr.

[0193] The second embodiment is an embodiment of the transformation of a near-zero carbon emission fossil energy production device. The transformation process is basically the same as the second implementation process of Example 6, and the effect after implementation is also basically the same: the coal-fired power plant achieves near-zero carbon emissions, its carbon capture and storage rate reaches 95%, and the total CCS volume is 19Mt / yr.

[0194] The third embodiment is a net-zero carbon emission fossil energy production equipment transformation embodiment, which is carried out on the basis of the second embodiment and adds an ocean-based direct air carbon capture and storage (DACCS) system. All electricity required for the newly added DACCS system and the original CCS system is supplied by carbon-free energy power generation systems such as wind power stations and / or photovoltaic power stations. After implementation, the coal-fired power plant will achieve overall net-zero carbon emissions, with a flue gas carbon capture and storage rate of 95%, a total CCS volume of 19Mt / yr, and a total DACCS volume of 1Mt / yr, which is equivalent to the remaining amount after carbon capture and storage. The total carbon reduction of CCS+DACCS is 20Mt / yr, which is equivalent to the 20Mt / yr of CO2 produced by the coal-fired power plant.

[0195] All new CCS and / or DACCS processes are deployed offshore, solving the problem of lack of CCS deployment space in existing coastal power plants.

[0196] Example 10: A low-carbon transformation example for a coastal gas-fired power plant. The power plant uses liquefied natural gas (LNG) as fuel and is equipped with three gas-steam combined cycle generator sets, each with a capacity of 400 MW, for a total of 1,200 MW. The exhaust gas temperature from the waste heat boiler is approximately 85-100°C, with a very low SO2 content, requiring no desulfurization. The flue gas contains approximately 7% CO2. The implementation process of this embodiment includes: 1) installing a flue gas bypass gate 1.3, as required by the process of the present invention, on the exhaust duct of the power plant's waste heat boiler. The existing exhaust stack of the power plant is then replaced with a flue gas bypass exhaust stack 1.4, as required by the process of the present invention. 2) Offline construction and commissioning of a CCS offshore platform 2.1, a floating dock 2.1-3, is constructed on which a seawater scrubbing pre-processor 2.3 is installed to treat the high-temperature CO2-containing flue gas discharged from the power plant into a CO2-containing gas stream at a temperature of approximately 30°C. The platform also includes a decarbonization absorption tower 2.12, a neutralizer 2.18, an offshore flue 2.2, and other CCS process facilities. 3) During planned maintenance outages of the power plant, the floating dock and its CCS system are connected, and / or the existing flue gas bypass gate 1.3 is utilized to switch to the CCS system without shutting down the power plant. The CCS system is powered by the power plant's electricity consumption. After implementation, the gas-fired power plant achieves near-zero carbon emissions, with a carbon capture and storage rate exceeding 95%.

[0197] Natural gas power plants, represented by gas-steam combined cycle processes, have carbon emissions halved compared to coal-fired power plants of the same power generation capacity. However, their total scale is not small and continues to expand, and their impact on global carbon emissions is greater than that of coal-fired power plants. The adoption of the technical solution of the present invention to achieve low-carbon transformation of gas-fired power plants is of great significance to achieving climate goals.

[0198] The protection scope of the claims of the present invention is not limited to the above-mentioned embodiments.

Claims

1. A net zero carbon fossil energy production method, characterized in that: The method comprises: 1) Burning fossil fuels to produce energy and fossil fuel flue gas; 2) pre-treating the fossil fuel flue gas by cooling and / or desulfurizing to generate pre-treated flue gas; 3) using decarbonized absorbing seawater to capture carbon from the pretreated flue gas, thereby generating decarbonized absorbing seawater and decarbonized gas; 4) discharging the decarbonized gas into the atmosphere; 5) Inject the decarbonized seawater into the ocean for carbon storage.

2. The method according to claim 1, characterized in that The temperature of the flue gas after pretreatment is no higher than 50°C, or no higher than 30°C, or no higher than 20°C, or no higher than 10°C, or no higher than 5°C than the water temperature of the decarbonized and absorbed seawater; the SO2 volume content of the flue gas after pretreatment is less than 100ppm, or less than 80ppm, or less than 30ppm.

3. The method according to claim 1, characterized in that The method further comprises: providing a CCS offshore platform, and performing the washing on the CCS offshore platform to reduce the pumping height and power consumption of the decarbonized absorbed seawater.

4. The method according to claim 1, characterized in that In step 5), before the decarbonized seawater is discharged into the ocean, it is first mixed with neutralized seawater to form mixed seawater, so that the pH value is increased to meet the statutory discharge standard, so that the CO2 absorbed by the seawater is converted into bicarbonate ions (HCO3 — ) and injected into the ocean to achieve ionic ocean carbon sequestration.

5. The method according to claim 1, characterized in that The method also includes: detecting and measuring the carbon dioxide equivalent (CO2e) in the absorbed and captured fossil fuel flue gas by detecting and measuring the difference between the CO2 content of the fossil fuel flue gas and the CO2 content of the desulfurized gas; the CO2e measurement data is transmitted to the carbon accounting system in real time or periodically.

6. The method according to claim 1, characterized in that The method also includes providing a carbon-free energy generation system and / or a direct atmospheric carbon capture and storage (DACCS) system.

7. A net zero carbon fossil energy carbon capture and storage (CCS) system, characterized in that: The system comprises: A pre-processor, cooling and / or desulfurizing the fossil fuel flue gas to generate pre-treated flue gas; A decarbonization absorption tower, which uses decarbonization absorption seawater to wash the pretreated flue gas to absorb and capture carbon dioxide, generate decarbonization absorption seawater and decarbonization gas, and discharge the decarbonization gas into the atmosphere; Decarbonization absorption seawater supply equipment is used to pump seawater extracted from the ocean to the decarbonization absorption tower to become decarbonization Carbon absorbs seawater; The discharge equipment is used to discharge the decarbonized and absorbed seawater into the ocean for carbon sequestration.

8. The system according to claim 7, characterized in that The energy for extracting and pumping the decarbonized absorbed seawater from the ocean is provided by a carbon-free energy generation system; the carbon-free energy generation system includes one or more of wind energy, solar energy, wave energy, tidal energy, and nuclear energy; the carbon-free energy generation system includes an energy storage device to ensure uninterrupted power supply.

9. The system according to claim 7, characterized in that The pre-treater is configured to scrub the fossil fuel flue gas with pre-treated seawater to achieve cooling and / or desulfurization pre-treatment.

10. The system according to claim 7, characterized in that In the pretreated flue gas, the volume content of SO2 is less than 100 ppm, or less than 80 ppm, or less than 30 ppm.

11. The system according to claim 7, characterized in that The temperature of the flue gas after pretreatment is no higher than the water temperature of the decarbonized and absorbed seawater by 50°C, 30°C, 20°C, 10°C or 5°C.

12. The system according to claim 7, characterized in that The discharge equipment also includes a neutralizer for mixing the decarbonized absorbed seawater with the neutralized seawater to form mixed seawater, so that the pH value is increased to meet the statutory discharge standards.

13. The system according to claim 7, characterized in that The system further comprises a CCS offshore platform, and the pre-processor and / or the decarbonation absorption tower and / or the neutralizer are located on the CCS offshore platform to reduce the height and power consumption of pumping seawater.

14. A blue carbon power plant, comprising a fossil energy system, wherein the fossil energy system generates electricity by burning fossil fuels to produce fossil fuel flue gas, characterized in that: The blue carbon power plant further comprises a CCS (carbon capture and storage) system as claimed in claim 7, which is used for decarbonizing the fossil fuel flue gas.

15. The blue carbon power plant according to claim 14, characterized in that: The CCS system also includes a neutralizer and a CCS marine platform, as well as a carbon-free energy power generation unit; the pre-processor, the decarbonization absorption tower, and the neutralizer are located on the CCS marine platform; the CCS marine platform is configured as a floating and / or lifting marine platform that rises and falls with the tide; the pre-processor is configured to wash the fossil fuel flue gas with pre-treated seawater to achieve cooling and / or desulfurization pretreatment; the pre-treated seawater, decarbonization absorption seawater, and neutralization seawater are extracted from the ocean, and the energy required for extracting seawater is provided by the carbon-free energy power generation system and / or the power station itself; at least 95%, or 90%, or 85%, or 80%, or 75%, or 70%, 60%, or 50% of the carbon dioxide in the fossil fuel flue gas is captured and stored; the CCS system also includes a direct air carbon capture and storage (DACCS) system for directly capturing and storing carbon dioxide from the atmosphere, and the amount of carbon dioxide captured and stored is equal to the amount of carbon dioxide in the decarbonized gas discharged into the atmosphere.

Images