Method for generating thermal and / or electrical energy
Patent Information
- Application Number
- EP2023772432
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-10-19
- Filing Date
- 2023-09-12
- Publication Date
- 2025-08-27
Smart Images
Figure 1.1
Abstract
Description
[0001] Process for generating thermal and / or electrical energy
[0002] Description
[0003] The invention relates to a method for generating thermal and / or electrical energy.
[0004] Since the beginning of the Industrial Revolution in 1800, the concentration of CO2 in the atmosphere has increased from a previously stable 280 ppmv (parts per million by volume) to 410 ppmv in 2020. This increase is predicted to continue or even intensify unless techniques are implemented to curb carbon emissions.
[0005] The ratified Paris Agreement sets as its primary goal the goal of keeping the increase in global average temperature below 2°C above pre-industrial levels, which requires reducing carbon dioxide emissions to zero by 2050. Proposals to limit these emissions include the use of biofuels, solar energy, and wind turbines. However, reducing current carbon dioxide emissions and thus limiting the increase in atmospheric CO2 is not sufficient in the long term to correct the imbalance between oxygen and CO2 in the atmosphere caused by the previous overproduction of CO2.
[0006] Today's energy supply network, which is used to distribute electricity and / or district heating in particular, is based primarily on the combustion of fossil fuels, especially natural gas and coal, in addition to energy generation from nuclear fuels. This is associated with high CCh emissions. Although combined heat and power (CHP) has already reduced CCh emissions, particularly through the combustion of waste as fuel, a more climate-friendly, particularly climate-neutral or CCh-neutral, energy supply requires a global approach that considers all processes leading up to energy generation and, in particular, also considers the production of the fuel used. The object of the invention is therefore to provide a method for energy generation with the goal of significantly improving the CCh balance of the global energy supply.
[0007] The solution to this problem is provided with regard to the method by the subject matter of patent claim 1.
[0008] The invention solves the above-mentioned problem by a method for generating electrical energy and / or thermal energy with the following steps:
[0009] - Producing a liquid fuel in an atmospheric carbon dioxide-reducing process, which is supplied with electricity from, in particular exclusively, at least one renewable energy source and comprises the following steps: a) producing oxygen in an electrolysis unit, which receives a quantity of water, in particular from the sea, through at least one water supply line and decomposes the absorbed quantity of water into an oxygen subset and a hydrogen subset; b) passing a first portion of the hydrogen subset from the electrolysis unit to a carbonization unit and a second portion of the hydrogen subset to a fuel synthesis unit;c) Purifying ambient air in at least one carbon dioxide sorption unit, wherein the carbon dioxide sorption unit takes in the ambient air through at least one air inlet and extracts a quantity of carbon dioxide from the ambient air in at least one downstream sorber device; d) Passing a first portion of the carbon dioxide quantity to the carbonation unit and a second portion of the carbon dioxide quantity to the fuel synthesis unit; e) Producing carbon in the carbonation unit, in particular by methane synthesis and methane cracking and / or by methanol synthesis and methanol cracking, and f) Combining the second portion of the hydrogen portion and the second portion of the carbon dioxide quantity in the fuel synthesis unit to produce the liquid fuel, and;
[0010] - Using the liquid fuel to generate a quantity of thermal energy and / or electrical energy in a stationary thermal plant.
[0011] The invention enables the generation of thermal and / or electrical energy not only in a CCh-neutral manner, but even in a CCh-reducing or CCh-negative manner. By sorbing CO2 from the ambient air, the CCh content in the Earth's atmosphere is reduced, thus gradually reversing the steady increase in CCh pollution over the past decades and centuries. At the same time, the invention enables the production of pure oxygen and thus also reduces the CCh content in the Earth's atmosphere. The liquid fuel used in the invention is therefore CCh-negative, meaning that more CO2 is removed from the Earth's atmosphere during its production than is subsequently released through its combustion.
[0012] Preferably, the negative proportion in the CCh balance of the process according to the invention is at least 5%, in particular at least 3%, in particular at least 10%, in particular at least 20%, in particular at least 30%, in particular at least 50%, in particular at least 100%, in particular at least 200%. It is expected that the current climate change caused by industrial development will be slowed in the short term, stopped in the medium term, and reversed in the long term through worldwide, widespread use of the invention.
[0013] To actively reduce the CCh content in the atmosphere, the carbon produced in the carbonization unit is preferably fed to a carbon storage facility. The carbon storage facility can, in particular, be an ocean or a seabed. In other words, the carbon, in particular in the form of graphite, can be permanently stored on the seabed. In this respect, a preferred embodiment of the invention provides that step e) of the process for producing the liquid fuel comprises transporting the carbon, in particular to a long-term carbon storage facility, in particular a region of the seabed.
[0014] The stationary thermal power plant may be a turbine-driven power plant and / or an engine-driven power plant and / or a combined heat and power plant and / or a heating plant.
[0015] It is advantageous if the liquid fuel is produced in a production facility that is spatially separated from the stationary, thermal plant. Separating fuel production from fuel use makes it possible, on the one hand, to produce the liquid fuel where the energy required for production, preferably generated from renewable sources, is available. This could be, for example, near an offshore wind farm or a photovoltaic system, although these can be located in locations around the world that enable high efficiency of renewable energy generation. These could be regions with strong and consistent wind or high levels of solar radiation, for example.
[0016] On the other hand, the stationary thermal power plant can be located where the thermal and / or electrical energy generated in the plant is needed, for example, near an industrial production facility or a residential area. The distance between the production facility and the stationary thermal power plant can be at least 50 km, in particular at least 100 km, preferably at least 500 km.
[0017] Particularly in the case of spatially separated fuel production and fuel use, it can preferably be provided that the liquid fuel can be transported from the production plant to the stationary, thermal plant by at least one transport system, in particular a pipeline or a tanker. In a particularly preferred embodiment of the invention, the production plant comprises a photovoltaic system as a renewable energy source. The photovoltaic system can be located in a region with a global horizontal solar radiation per year of at least 1,500 kWh / m 2 , in particular 2000 kWh / m 2The problem of rising CCh emissions is global, and therefore global efforts are required to solve this problem and save the global climate. Therefore, it is desirable to operate the inventive process efficiently on a large scale. The use of photovoltaics as a renewable energy source has the advantage that regions with high global horizontal solar radiation often also have access to the sea. This allows production plants for the liquid fuel required for the invention to be operated very efficiently, since all the necessary starting components—solar energy, CO2, and water—are available within a short distance. Furthermore, energy generation using a photovoltaic system is very cost-effective. Compared to other technologies for renewable energy generation, energy generation using photovoltaics is three to ten times more cost-effective.This is particularly true if the process is carried out in a production facility located in a region with high hours of sunshine or high global horizontal solar irradiance, for example in Saudi Arabia.
[0018] The extraction of the carbon component from the atmosphere can be achieved through a two-stage process, for example, methane synthesis followed by methane cracking. During methane synthesis, the hydrogen fed to the carbonization unit is converted with the carbon also fed into the carbonization unit to form methane, which is then separated again through methane cracking. A Kvaerner process can be used for this. Alternatively, methane cracking can involve a methane pyrolysis process, known as a Monolith process. Advantageously, a methane cracking method is used in which the separated carbon is discharged as a solid. This is achieved, for example, in a Kvaerner process.
[0019] Furthermore, alternatively or additionally, the carbon can be produced by methanol synthesis and methanol cleavage. The (waste) heat generated during carbonization in the carbonization unit can be directed to the carbon dioxide sorption unit and used there as energy for carbon sorption. Additionally or alternatively, the (waste) heat from the fuel synthesis unit can be directed to the carbon dioxide sorption unit and used there as energy for carbon sorption. This further increases the efficiency of the overall process and reduces the process's primary energy requirements.
[0020] Preferably, the oxygen fraction and the purified ambient air are released into the outside atmosphere, while the hydrogen fraction and the carbon dioxide fraction are converted into water, carbon, and heat in the carbonization unit. This allows for a reduction in the carbon dioxide content in the atmospheric air and thus the balancing of an existing imbalance in the quantities of these air constituents.
[0021] The invention will be explained in more detail below with reference to the accompanying drawing. The single figure shows a perspective view of a production plant for producing a CO2-negative liquid fuel.
[0022] The invention essentially comprises two steps, the production of a CO2-negative liquid fuel in a production plant on the one hand and the use of this liquid fuel in a stationary, calorific plant for the generation of thermal and / or electrical energy on the other hand.
[0023] The production of the CCh-neutral liquid fuel preferably takes place in a production facility 10 located in an area with high global horizontal solar radiation and near the sea, for example, in Saudi Arabia. The production facility 10 is preferably a large-scale power plant. The production facility 10 can have at least one assembly area 18 connected to a foundation of a building and / or structure.
[0024] The production plant 10 may comprise an electrolysis unit 11 for producing oxygen and a carbon dioxide sorption unit 12 for purifying the ambient air UL of the external atmosphere surrounding the production plant 10. In general, it is possible for the electrolysis unit 11 and / or the carbon dioxide sorption unit 12 to be arranged in a common building or in separate buildings. The production plant 10 may further comprise a power generation unit 31 for the autonomous power supply of the production plant.
[0025] 10, which will be discussed in more detail later.
[0026] The electrolysis unit 11 is designed to convert a water quantity M H2O into a partial amount of oxygen MO2 and a partial amount of hydrogen by electrolysis. The electrolysis unit 11 thus forms a unit for water electrolysis. The electrolysis unit 11 is connected to a water supply line 13 for receiving the water quantity M H2O. As can be seen in Fig. 1, a pump unit 25 is arranged between the electrolysis unit 11 and the water supply line 13. The pump unit 25 has at least one pump for conveying water from a water reservoir 26. The water reservoir 26 can be a sea with seawater.
[0027] In order to prepare the seawater for the electrolysis process via the electrolysis unit 11, the production plant 10 can have a seawater desalination unit 27. The seawater desalination unit 27 is adapted to separate a certain salt content from the extracted seawater quantity M H2O, so that the seawater has a reduced salt content after the desalination process by the seawater desalination unit 27. The desalinated seawater quantity M H 2O corresponds to the amount of water M H 2O, which is decomposed by the electrolysis unit 11 into an oxygen partial quantity MO2 and a hydrogen partial quantity. The electrolysis unit 11 is connected to the seawater desalination unit 27 by at least one pipeline. To discharge the generated oxygen partial quantity MO2, the electrolysis unit
[0028] 11 has an oxygen outlet 16 which opens into the outside atmosphere. It is possible for the electrolysis unit 11 to have one or more oxygen outlets 16 for discharging the generated oxygen partial quantity M 02 has.
[0029] The production plant 10 further comprises at least one (not shown) hydrogen transport device adapted to provide a first portion of the hydrogen partial quantity separated from the water quantity M H2O to a carbonation unit 34 for further processing. A second portion of the hydrogen partial quantity can be fed to a fuel synthesis unit 37, for example, a methanol synthesis unit. According to Fig. 1, the carbon dioxide sorption unit 12 has an air inlet 14 for supplying the ambient air UL and a downstream sorber device 15. It is possible for the carbon dioxide sorption unit 12 to have one or more air inlets 14. The sorber device 15 is connected to the air inlet 14. The sorber device 15 is adapted to extract a quantity of carbon dioxide from the ambient air UL. The carbon dioxide sorption unit 12 further has an air outlet 17.The air outlet 17 serves to discharge the ambient air UL' purified of carbon dioxide. The air outlet 17 can be oriented vertically upwards and / or be part of a chimney 19.
[0030] Specifically, the sorber device 15 is arranged between the air inlet 14 and the air outlet 17. During operation, the ambient air UL flows through the air inlet 14 to the sorber device 15, which separates, in particular filters, a specific amount of carbon dioxide from the air UL. The purified ambient air UL' flows out of the sorber device 15 through the air outlet 17 into the outside atmosphere.
[0031] The production plant 10 further comprises a carbon dioxide transport device designed to make the carbon dioxide separated from the ambient air UL available to a carbon dioxide buffer and / or the carbonization unit 34 of the production plant 10 for further processing. Preferably, the first part of the hydrogen subset and the first part of the carbon dioxide subset are thus fed to the carbonization unit 34, so that the extracted carbon dioxide is processed with the separated hydrogen subset to form further intermediate and / or end products. Specifically, the first part of the carbon dioxide subset and the second part of the hydrogen subset can be converted into water, carbon (graphite), and heat by the methanation carried out in the carbonization unit 34.
[0032] As shown in Fig. 1, the production plant 10 has a flat plant area 23. The flat plant area 23 preferably connects directly to the electrolysis unit 11. A power generation unit 31, which is a photovoltaic system 24, is arranged on the flat plant area 23. The photovoltaic system 24 is connected to the respective units of the production plant 10 for power supply. The photovoltaic system 24 is adapted such that the entire production plant 10 can be operated in an energy-self-sufficient manner. This means that the electrical power for operating the entire production plant 10 can be provided exclusively by solar energy via the photovoltaic system 24. In other words, fossil energy sources are preferably not used to operate the production plant 10.The power generation unit 31 preferably comprises an energy storage device (not shown) adapted to supply the production facility 10 with power during nighttime operation. As an alternative to the photovoltaic system 24, other units for generating renewable electrical energy, such as wind turbines, particularly offshore wind farms, can also be used.
[0033] The above-described seawater desalination unit 27 is connected to a water return line 28 through which a recirculating seawater volume M'HZO with an increased salinity is returned to the sea. Specifically, a specific salinity is extracted from the extracted seawater volume and then returned to the sea with a portion of the extracted seawater volume as the recirculating water volume M'HZO. This creates a water cycle that is harmless to nature.
[0034] The production plant 10 further comprises a fuel synthesis unit 37. The fuel synthesis unit 37 is connected to the electrolysis unit 11 or a hydrogen buffer storage unit via a hydrogen transport device and to the carbon dioxide sorption unit 12 via a carbon dioxide transport device. From the supplied hydrogen and carbon, the fuel synthesis unit 37 synthesizes a liquid fuel, preferably methanol, which can be withdrawn from the production plant 10 via a fuel outlet 38. The fuel can be distributed to decentralized fuel depots worldwide, in particular by means of a fuel distribution system that can include pipelines, ships, in particular tankers, tank freight trains, and / or tank trucks. The fuel depots can in particular be connected to stationary, thermal plants in order to make the fuel available there for the operation of the respective plant.By appropriately controlling the process in the production plant 10, it is possible to adjust the proportion of the carbon sorbed in the carbon dioxide sorption unit used for the production of liquid fuel or for the production of graphite for storage in a carbon storage facility. Initially, a ratio of 20% graphite to 80% liquid fuel is expected to be appropriate. The proportion of liquid fuel can be gradually reduced over time, and the proportion of graphite can be increased as the demand for liquid fuel production decreases, particularly through the construction of additional production plants 10.
[0035] The method for operating the production plant 10 and thus for producing CCh-negative fuel is described in more detail below.
[0036] In a first process step, a quantity of water M HZO is taken up through the water supply line 13 by means of the electrolysis unit 11 for oxygen production. The taken-up quantity of water M HZO is then decomposed into an oxygen partial quantity MO 2 and a hydrogen partial quantity by an electrolysis process. The hydrogen partial quantity is made available to a carbonization unit 34 for further processing by at least one hydrogen transport device. In the present embodiment, the carbonization unit 34 effects a methanation process that comprises methane synthesis and methane splitting.
[0037] In a second process step, ambient air UL of an external atmosphere surrounding the production plant 10 is purified by the carbon dioxide sorption unit 12. The ambient air UL is introduced, in particular sucked in, through several air inlets 14 into the flow channels 21 and fed to the downstream sorber devices 15. The sorber devices 15 then extract a quantity of carbon dioxide from the supplied ambient air UL. A first portion of the carbon dioxide quantity is fed by the carbon dioxide transport device to the carbonization unit 34 for methanation. Subsequently, the obtained partial oxygen quantity MO2 is released into the outside atmosphere after the decomposition process, and the purified ambient air UL' is released after the extraction of the carbon dioxide quantity. This increases the oxygen content in the air and reduces the CO2 content in the air.The first part of the hydrogen subset is further converted together with the first part of the carbon dioxide into water, carbon or graphite and heat by means of the methanation process.
[0038] In this process, seawater is desalinated and then split into hydrogen and oxygen by electrolysis. The oxygen O2 is released into the ambient air, particularly the atmosphere, thereby increasing the oxygen content in the vicinity of the production facility. At the same time, carbon dioxide CO2 is collected from the ambient air UL, particularly the atmosphere, by means of carbon dioxide sorption. As with the electrolytically produced hydrogen or the partial amount of hydrogen, the first portion of the carbon dioxide extracted from the ambient air UL is also fed to the carbonation unit 34.
[0039] The carbon or graphite can then be transported to a carbon storage facility via the carbon transport device 35. The carbon storage facility can be, for example, the water reservoir 26 or the ocean. Since the graphite produced in the methanation process contains little to no impurities and is solidified like rock, there are no concerns about dumping the graphite in the ocean.
[0040] In addition to the carbon-reducing process mentioned above, a second portion of the hydrogen and a second portion of the carbon dioxide are fed to the fuel synthesis unit 37 and combined there to produce the CCh-negative liquid fuel. Waste products, such as hydrogen and / or oxygen, from the methanation process can be used for fuel synthesis.
[0041] The energy required for electrolysis, carbon dioxide sorption and methanation comes from renewable energy sources, specifically the photovoltaic system 24, so that no additional carbon dioxide production occurs here.
[0042] The process described here therefore makes it possible to efficiently remove carbon dioxide from the Earth's atmosphere and break it down into its components, graphite and oxygen, while simultaneously producing a liquid fuel that has less impact on climate change than any known fossil fuel. The oxygen can be returned to the atmosphere, and the graphite can be permanently stored in a carbon reservoir, such as the ocean. During the production of the CCh-negative liquid fuel, CO2 is removed from the atmospheric air and the excess carbon is stored in a carbon reservoir. In this way, the process efficiently improves atmospheric air quality.
[0043] Reference symbol list
[0044] 10 Production plant
[0045] 11 Electrolysis unit
[0046] 12 Carbon dioxide sorption unit
[0047] 13 Water supply line
[0048] 14 Air intake
[0049] 15 Sorber facility
[0050] 16 Oxygen outlet
[0051] 17 Air outlet
[0052] 18 Assembly area
[0053] 19 Fireplace
[0054] 23 Large plant area
[0055] 24 photovoltaic systems
[0056] 25 Pump unit
[0057] 26 Water reservoir
[0058] 27 Seawater desalination unit
[0059] 28 Water return line
[0060] 29 Partial longitudinal extension
[0061] 31 power generation units
[0062] 32 Longitudinal extension
[0063] 33 Transverse extension
[0064] 34 Carbonation unit
[0065] 35 Carbon transport facility
[0066] 36 Carbon outlet
[0067] 37 Fuel synthesis unit
[0068] 38 Fuel outlet
[0069] UL ambient air
[0070] UL' Purified Ambient Air
[0071] MH2O Amount of water withdrawn M'H2O Amount of water returned MQ2 Partial oxygen quantity
Claims
Claims Method for generating electrical energy and / or thermal energy with the following steps: - Producing a liquid fuel in an atmospheric carbon dioxide-reducing process which is supplied with electricity from, in particular exclusively, at least one renewable energy source and comprises the following steps: a) producing oxygen in an electrolysis unit (11) which receives a quantity of water (MH20), in particular from the sea, through at least one water supply line (13) and decomposes the absorbed quantity of water (MH20) into an oxygen partial quantity (MO2) and a hydrogen partial quantity; b) conducting a first part of the hydrogen partial quantity from the electrolysis unit (11) to a carbonation unit (34) and a second part of the hydrogen partial quantity to a fuel synthesis unit (37);c) cleaning ambient air (UL) in at least one carbon dioxide sorption unit (12), wherein the carbon dioxide sorption unit (12) takes in the ambient air (UL) through at least one air inlet (14) and extracts an amount of carbon dioxide from the ambient air (UL) in at least one downstream sorber device (15); d) passing a first part of the amount of carbon dioxide to the carbonization unit (34) and a second part of the amount of carbon dioxide to the fuel synthesis unit (37); e) producing carbon in the carbonization unit (34), in particular by methane synthesis and methane cracking and / or by methanol synthesis and methanol cracking, and f) combining the second part of the hydrogen partial amount and the second part of the amount of carbon dioxide in the fuel synthesis unit (37) to produce the liquid fuel, and; Using the liquid fuel to generate a quantity of thermal energy and / or electrical energy in a stationary, thermal plant.
2. Method according to claim 1, characterized in that Step e) comprises transporting the carbon, in particular to a long-term carbon store, in particular an area of the seabed.
3. Method according to claim 1 or 2, characterized in that the stationary thermal plant is a turbine-driven power plant and / or an engine-driven power plant and / or a combined heat and power plant and / or a heating plant.
4. Method according to one of the preceding claims, characterized in that the liquid fuel is produced in a production plant which is spatially separated from the stationary, thermal plant.
5. The method according to claim 4, characterized in that the liquid fuel is transported by at least one transport system, in particular a pipeline or a tanker, from the production plant to the stationary, calorific plant.
6. Method according to claim 4 or 5, characterized in that the production plant comprises a photovoltaic system as a renewable energy source and is located in a region with a global horizontal solar radiation per year of at least 1,500 kWh / m 2 is located.