Direct carbon dioxide capture from the air

Abstract

A method for removing carbon dioxide from a gas containing carbon dioxide, comprising contacting the gas containing carbon dioxide with a fluidized solid adsorbent to remove carbon dioxide from the gas and form a gas from which carbon dioxide has been removed.

Description

[Technical Field]

[0001] The present invention relates to a method for removing carbon dioxide from a gas using a solid adsorption material. [Background technology]

[0002] Preventing global warming is more important than ever. The concentration of carbon dioxide in the atmosphere (one of the most important greenhouse gases) has increased from approximately 280 ppm in the pre-industrial era to approximately 400 ppm today. To prevent global warming, a diverse portfolio of technologies is needed to reduce and / or prevent the release of new carbon dioxide emissions into the atmosphere at sources and to remove existing carbon dioxide from the atmosphere. Without large-scale and permanent removal of carbon dioxide from the atmosphere, achieving ambitious climate change mitigation targets will be extremely difficult.

[0003] One way to achieve this is by using direct air capture (DAC). DAC is a process that allows for the direct removal of carbon dioxide from the atmosphere, thereby reducing the concentration of carbon dioxide in the atmosphere and helping to prevent global warming.

[0004] Many standard DAC systems have one major challenge to overcome: because of the low concentration of carbon dioxide in the atmosphere, a large volume of air must pass through the system to extract the required amount of carbon dioxide from the atmosphere. Ultimately, this means that for it to be economically viable, the pressure drop between the inlet and outlet of the air passing through the DAC system must be very low. Otherwise, the energy required to pump the air through the system makes it uneconomical. The cost of operating these standard DAC systems is significant and is a barrier to large-scale use of DAC systems. Fluidized bed reactors are sometimes used in DAC systems.

[0005] This disclosure aims to mitigate, to at least some extent, the problems associated with the prior art and / or to address, to at least some extent, the difficulties associated with the prior art. [Overview of the Initiative]

[0006] A first aspect of this disclosure provides a method for removing carbon dioxide from a gas containing carbon dioxide. The method includes the step of contacting a gas containing carbon dioxide with a fluidized solid adsorbent to remove carbon dioxide from the gas and form a gas from which carbon dioxide has been removed.

[0007] Removing carbon dioxide from a gas means removing some (but not all) of the carbon dioxide from a gas containing carbon dioxide, thereby forming a gas from which the carbon dioxide has been removed. "Bringing a gas into contact with a fluidized solid adsorbent" means bringing the gas into contact with the solid adsorbent (which may be the adsorbent particles if the adsorbent contains particles). A "fluidized" solid adsorbent means that the solid adsorbent is not stationary but fluidized, i.e., it is moved from its stationary position by the force of the gas. The solid adsorbent can be, without limitation, a mixture of solid adsorbents. The solid adsorbent can be, without limitation, a nanostructured adsorbent, or may contain one. A solid adsorbent mixture containing a nanostructured adsorbent means that the solid adsorbent mixture contains a nanostructured adsorbent among other components.

[0008] When used herein to define an adsorbent, "nanostructure" means that the adsorbent has a large internal surface area with three-dimensional porous structural properties on a nanostructure scale (approximately 1 to 100 nanometers) that provides a surface area for the reaction to occur, although the adsorbent is not necessarily limited to nanoparticle size in terms of nominal particle diameter (i.e., not 1 to 100 nanometers in diameter). Advantageously, the use of nanostructured adsorbents results in better mechanical stability compared to non-nanostructured adsorbent particles by reducing abrasion properties and / or adsorbent breakage, and by maintaining or improving internal surface area and / or porosity, thereby maintaining or improving the chemical reactivity between the adsorbent particles and carbon dioxide. Enhancement of adsorbent particles to form nanostructured adsorbents as defined herein can be achieved by doping, mixing, calcining, or stabilization with inert components, and / or vapor reactivation of the adsorbent particles.

[0009] Advantageously, fluidized solid adsorbents can act like turbulent fluids, increasing the rate of mass and heat transfer between the solid adsorbent and the gas. Advantageously, nanostructured adsorbents can increase the rate of carbon dioxide adsorption from the gas by increasing the internal surface area of ​​the nanostructured adsorbent.

[0010] Optionally, a gas containing carbon dioxide is brought into contact with a solid adsorbent in the presence of water or one or more solvents, or a mixture of water and one or more solvents. Advantageously, this results in an increased carbonation rate. Carbonation is used herein to refer to the rate at which carbon dioxide is removed from the gas stream. The water or solvent may, advantageously, be supplied in droplet form, which can be produced using a sprayer or diffuser.

[0011] Optionally, water may be provided by humidifying a gas containing carbon dioxide to substantially 100% humidity. Alternatively, water may be provided by passing a gas containing carbon dioxide through water and aerating it before contacting a solid adsorbent. Alternatively, water may be provided by vapor injection.

[0012] Optionally, a gas containing carbon dioxide is brought into contact with a solid adsorbent in one or more reactors. Advantageously, using reactors means that the process can be contained and the point of contact between the gas and the solid adsorbent can be controlled. Multiple reactors can be used in the same location to increase the amount of carbon dioxide removed. Such reactors may operate in parallel or in series. Instead of (or in addition to, if multiple reactors are used), a recycling line may be provided to recycle the carbon dioxide-free gas and pass it further through one or more reactors. Advantageously, by providing multiple reactors in parallel or in series, and / or the aforementioned recycling line, the carbonation conversion can be controlled to some extent to a selected / optimal level.

[0013] Optionally, one or more reactors may be one or more fluidized bed reactors. A fluidized bed reactor is a reactor having a bed of material (in this case, a solid adsorbent) inside, and a fluidized solid adsorbent can be obtained by moving the material from a stationary bed position to a fluidized bed position by applying a fluidizing gas. Advantageously, by fluidizing the solid adsorbent, the contact between the fluidizing gas and the bed material can be increased, and therefore the transfer speed between the fluidizing gas and the bed material can be increased.

[0014] Optionally, one or more fluidized bed reactors have a width-to-length aspect ratio in the range of 1:1 to 1:20, preferably 1:5, more preferably 1:3. Optionally, the fluidized bed reactors are horizontal fluidized bed reactors. Advantageously, these preferred aspect ratios ensure that the fluidized bed reactors can fit into standard transport containers, facilitating equipment transport. Advantageously, compared to standard vertical fluidized bed reactors with the same mass of floor material, horizontal fluidized beds can have much shallower floor heights, resulting in lower gas pressure drops across the floor. Advantageously, shallower floor heights mean reduced costs associated with moving gas across the floor.

[0015] Optionally, a gas containing carbon dioxide is brought into contact (for example, simultaneously) with a solid adsorbent in each of several fluidized bed reactors arranged in parallel. Each portion of the gas containing carbon dioxide may be brought into contact (for example, simultaneously) with a solid adsorbent in each of the several fluidized bed reactors arranged in parallel. The fluidized bed reactors can be stacked on top of each other to form a vertical stack of fluidized bed reactors.

[0016] Optionally, one or more fluidized bed reactors include multiple parallel-arranged fluidized bed subunits, and a gas containing carbon dioxide is brought into contact (e.g., simultaneously) with a solid adsorbent in each of the multiple parallel-arranged fluidized bed subunits. Each portion of the gas containing carbon dioxide may be brought into contact (e.g., simultaneously) with a solid adsorbent in each of the multiple parallel-arranged fluidized bed subunits. Fluidized bed subunits can be stacked on top of each other to form a vertical stack of fluidized bed subunits. Fluidized bed subunits may be housed in the same enclosure of the corresponding fluidized bed reactor. This is to ensure that, during use, the fluidized bed subunits are exposed to the same gas containing carbon dioxide entering the corresponding fluidized bed reactor.

[0017] By vertically stacking carbon dioxide-containing gas through parallel-arranged fluidized bed reactors or subunits, it is ensured that the pressure drop across each fluidized bed reactor or subunit is the same (reducing the energy cost of driving the flow of carbon dioxide-containing gas), while increasing the gas volume throughput, thereby increasing the processing capacity for a given reactor size and footprint. This improves reaction efficiency and allows for a reduction in the overall system size and material requirements while maintaining the necessary performance (particularly regarding the economical recovery of carbon dioxide from atmospheric air), thereby reducing the overall capital investment requirements for the system.

[0018] Furthermore, the parallel configuration of fluidized bed reactors or subunits allows for scaling the system's capacity by adding them vertically and / or laterally. This scaling flexibility enables easy deployment and installation of the system for a variety of locations and application requirements.

[0019] Optionally, one or more gas distributors are provided through which gas is introduced into one or more fluidized bed reactors. A gas distributor means any device capable of distributing gas within the reactor to produce a uniformly distributed gas flow. An example of a gas distributor is a perforated distribution plate, i.e., a plate perforated in multiple places to allow gas to enter the fluidized bed through the fluidized bed. Advantageously, the use of a gas distributor can increase contact between the fluidizing gas and the bed material (i.e., solid adsorbent), and therefore can increase the transfer rate between the fluidizing gas and the bed material.

[0020] Optionally, one or more fans are provided to introduce gas into one or more fluidized bed reactors. Advantageously, using multiple fans allows for the introduction of a larger volume of gas into the reactor.

[0021] Optionally, the solid adsorbent is moved from the solid inlet to the solid outlet along the length of the fluidized bed reactor. Optionally, one or more fans are configured to move the solid adsorbent gradually from the solid inlet to the solid outlet along the length of the fluidized bed reactor. Advantageously, this allows for replenishment of the solid adsorbent when it becomes fully saturated, without having to stop the process as a batch process to unload / reload the solid adsorbent. The combination of the rate at which one or more fans move the solid adsorbent from the solid inlet to the solid outlet and the rate at which new (and / or regenerated) solid adsorbent is added to the solid inlet can be selected to obtain the desired absorption rate. Optionally, if multiple fans are provided, they may be configured to provide a velocity gradient so that the solid adsorbent moves at different rates along the length of the fluidized bed reactor.

[0022] Optionally, one or more separation units are provided through which the gas from which carbon dioxide has been removed is filtered. The gas from which carbon dioxide has been removed is the gas that has been contacted with the solid adsorbent, i.e., it has passed through a bed of the fluidized solid adsorbent. Advantageously, by passing the gas stream from which carbon dioxide has been removed through one or more separation units, entrained particles of the solid adsorbent can be removed from the gas from which carbon dioxide has been removed before it is sent for further processing / storage / use, etc. A separation unit is a unit that can separate any entrained particles from the gas. A separation unit (e.g., a filter, a bag filter) can be provided inside the reactor, or a separation unit (e.g., a cyclone) can be provided outside the reactor. Multiple types of separation units can be provided.

[0023] Optionally, one or more separation units can be or include filters, bag filters, gas cyclones, or an electrostatic precipitator (ESP).

[0024] The gas containing carbon dioxide to be contacted with the fluidized solid adsorbent can be at a temperature in the range of -70°C to 500°C, preferably -70°C to 200°C, more preferably 15°C to 35°C, and even more preferably 20°C to 25°C. In particular, in addition to being applicable to recovering carbon dioxide from a gas containing carbon dioxide at a high temperature (e.g., higher than the ambient temperature), such as a flue or exhaust gas, the present invention is particularly applicable to recovering carbon dioxide from a gas containing carbon dioxide at a low temperature (e.g., air in the atmosphere at the ambient temperature).

[0025] Optionally, the gas containing carbon dioxide is contacted with the solid adsorbent at a temperature of 450°C to the ambient temperature (room temperature, e.g., substantially 20°C) and a pressure of 1 to 1.5 bar. Advantageously, this avoids high temperatures and pressures, which helps to reduce the costs that would otherwise be incurred as a result of heating and pressurizing the gas.

[0026] Optionally, the method may further include the step of regenerating the solid adsorbent, thereby releasing carbon dioxide from the solid adsorbent and producing a concentrated carbon dioxide gas. Advantageously, this allows the solid adsorbent to be recycled and reused.

[0027] Optionally, the solid adsorbent is regenerated in a second reactor. Advantageously, this allows for continuous removal of carbon dioxide in the first reactor and regeneration of the solid adsorbent in the second reactor.

[0028] Optionally, the solid adsorbent can be regenerated by heating it to a temperature of approximately 500-900°C.

[0029] Optionally, the method further includes a step of collecting concentrated carbon dioxide gas. Advantageously, this makes it possible to utilize and / or store the carbon dioxide removed from the gas stream.

[0030] Optionally, the method further includes a step of reactivating a solid adsorbent. Optionally, the reactivation step is performed after the regeneration step.

[0031] Optionally, the solid adsorbent is reactivated in the presence of vapor at a temperature ranging from ambient temperature (room temperature, e.g., substantially 20°C) to 900°C.

[0032] By choice, the gas containing carbon dioxide is the air in the atmosphere. The air in the atmosphere can be considered as any air that is removed from the atmosphere.

[0033] Optionally, the carbon dioxide-containing gas has a carbon dioxide concentration of less than 1000 ppm, more preferably less than 800 ppm, more preferably less than 600 ppm, and more preferably less than 500 ppm. Advantageously, the higher the carbon dioxide concentration, the faster the carbonation rate. However, a high concentration of carbon dioxide in the gas may mean that the system needs to pass through multiple times to completely remove all carbon dioxide from the gas. Advantageously, the process is optimized to remove virtually all carbon dioxide from atmospheric gas (i.e., gas containing 500–400 ppm of carbon dioxide).

[0034] Optionally, the solid adsorbent comprises solid adsorbent particles and optionally silica particles, wherein the average particle size of the solid adsorbent and optional silica particles is less than 2500 microns (μm). Using silica (if present), the aggregation of small adsorbent particles into larger particles having favorable fluidity properties can be achieved by surrounding the small adsorbent particles and forming a coating-like layer by electrostatic force.

[0035] Optionally, the solid adsorbent has an average particle size of 20 to 2000 microns and an internal surface area of ​​1 to 200 m². 2 The reaction rate is / g. Advantageously, the reaction rate can be increased by increasing the internal surface area of ​​the adsorbent available for the reaction to occur.

[0036] Optionally, the solid adsorbent is a mixed metal oxide or mixed metal hydroxide, and the metal component may be selected from the list of Ca, Mg, Si, Al, Fe, W, Mn, Cu, Zn, Xo, Sr, Cd, Ba, and Ni, or a mixture selected from this list. Preferably, the solid adsorbent is a mixed metal oxide or mixed metal hydroxide, and the metal component contains Ca. Advantageously, Ca adsorbs carbon dioxide from the gas. Advantageously, other metals may provide structural stability and resistance to wear and sintering for the adsorbent material.

[0037] Optionally, the solid adsorbent may comprise one or more salts, hydroxides, nitrates, nitrites, and / or carbonates of Li, Na, and / or K, and any combination of HBr, HCl, HNO3, and HI. Advantageously, incorporating one or more of the aforementioned components into the solid adsorbent increases the rate of the carbonation reaction.

[0038] The method may include a step of cooling the solid material after it has exited a reactor, preferably a calcining furnace reactor, wherein the solid material is cooled using a cooling gas. The method may include a step of transporting the solid material in a countercurrent with the cooling gas. The method may include a step of transporting the solid material in a countercurrent with the cooling gas using gravity. The method may include a step of transporting the solid material in a direct or alternating current with the cooling gas.

[0039] This method may include the step of cooling a solid material in a plurality of cooling stages. The plurality of cooling stages may include a plurality of parallel-arranged cooling stages configured to cool each portion of the solid material using a cooling gas during use. The plurality of cooling stages may include a plurality of sequentially arranged cooling stages configured to cool the solid material sequentially using a cooling gas during use.

[0040] The method may include a step of hydrating a solid material. The method may include a step of hydrating a solid material received from one of a plurality of sequentially arranged cooling stages, and / or a step of hydrating a solid material and providing the hydrated material to another cooling stage of the plurality of sequentially arranged cooling stages.

[0041] The method may include the step of cooling a solid material using a cooling gas, which is a fluidizing gas, using one or more fluidized bed coolers. One or more fluidized bed coolers may be in the form of multiple fluidized bed coolers arranged in parallel, or each fluidized bed cooler may include multiple fluidized bed cooler subunits. Fluidized bed coolers or fluidized bed cooler subunits may be stacked on top of each other to form a vertical stack of fluidized bed coolers or fluidized bed cooler subunits. Fluidized bed cooler subunits may be housed in the same enclosure as the corresponding fluidized bed cooler.

[0042] The cooling gas can be ambient air, without any limitations.

[0043] This method may include the step of supplying a cooled solid material to a reactor, preferably a carbonation reactor.

[0044] This method may include a step of recovering heat from the cooling of a solid material.

[0045] This method may include a step of heating the solid material with a heating gas before it enters a reactor, preferably a calcination furnace reactor. This method may include a step of conveying the solid material in a countercurrent with the heating gas. This method may include a step of conveying the solid material in a countercurrent with the heating gas using gravity. This method may include a step of conveying the solid material in a direct or alternating current with the heating gas.

[0046] This method may include the step of heating a solid material in a plurality of heating stages. The plurality of heating stages may include a plurality of parallel-arranged heating stages configured to heat each portion of the solid material using a heating gas during use. The plurality of heating stages may include a plurality of sequentially arranged heating stages configured to heat the solid material sequentially using a heating gas during use.

[0047] The method may include the step of cooling a solid material using a heating gas, wherein the heating gas is a fluidizing gas, using one or more fluidized bed heaters. The method may also include the step of heating a solid material using a heating gas, using one or more cyclone flash heaters. The one or more fluidized bed heaters may be in the form of multiple fluidized bed heaters arranged in parallel, or each fluidized bed heater may include multiple fluidized bed heater subunits. Fluidized bed heaters or fluidized bed heater subunits may be stacked on top of each other to form a vertical stack of fluidized bed heaters or fluidized bed heater subunits. Fluidized bed heater subunits may be housed in the same enclosure as the corresponding fluidized bed heater.

[0048] This method may include the step of receiving the solid material to be heated from a reactor, preferably a carbonation reactor.

[0049] This method may include a step of maintaining the heating temperature of the solid material at less than 550°C, preferably less than 500°C.

[0050] This method may include the step of heating a heating gas using heat recovered from the cooling of a solid material.

[0051] In the above method of the present invention, the solid material preferably refers to a solid adsorbent.

[0052] The heat recovery mechanism according to the present invention, particularly the use of countercurrent cooling / heating and heat recovery between the carbonation apparatus and the calcination furnace, improves the efficiency of heat recovery by increasing the temperature difference across the heat exchanger, thereby reducing the energy requirements for the DAC process. Furthermore, the heat recovery mechanism according to the present invention is useful in that it conserves sensible heat and therefore saves a large portion of the energy associated with the regeneration of the solid adsorbent. This improves the economic feasibility of the present invention, thereby making the system of the present invention a viable DAC option.

[0053] According to another aspect of the present invention, a system for removing carbon dioxide from a gas containing carbon dioxide is provided. The system comprises a solid adsorbent and is configured to, when in use, bring a gas containing carbon dioxide into contact with a fluidized solid adsorbent, thereby removing carbon dioxide from the gas and forming a gas from which carbon dioxide has been removed.

[0054] The system may be configured to bring a gas containing carbon dioxide into contact with a solid adsorbent in the presence of water, one or more solvents, or a mixture of water and one or more solvents during use. The system may be configured to supply water to humidify the gas containing carbon dioxide to approximately 100% humidity during use. For example, the system may include a humidifying device for performing such humidification. The system may be configured to blow the gas containing carbon dioxide through water before bringing it into contact with the solid adsorbent during use. For example, the system may include a blowing device for performing such blowing.

[0055] The system may include one or more reactors configured to bring a gas containing carbon dioxide into contact with a solid adsorbent during use. The one or more reactors may be one or more fluidized bed reactors. The one or more fluidized bed reactors may have a width-to-length aspect ratio in the range of 1:1 to 1:20, preferably 1:5, more preferably 1:3. The system may include a plurality of parallel-arranged fluidized bed reactors or fluidized bed subunits configured to bring a gas containing carbon dioxide into contact with a solid adsorbent during use, wherein the gas containing carbon dioxide is in contact (e.g., simultaneously) with the solid adsorbent in each of the plurality of parallel-arranged fluidized bed reactors or fluidized bed subunits. Multiple fluidized bed subunits may be contained within the same fluidized bed reactor. Each portion of the gas containing carbon dioxide may be in contact (e.g., simultaneously) with the solid adsorbent in each of the plurality of parallel-arranged fluidized bed reactors or fluidized bed subunits. Fluidized bed reactors or fluidized bed subunits may be stacked on top of each other to form a vertical stack of fluidized bed reactors or fluidized bed subunits. The fluidized bed subunit can be housed within the same enclosure as the corresponding fluidized bed reactor.

[0056] The system may include one or more gas distributors through which, when in use, gas is introduced into one or more fluidized bed reactors. The system may include one or more fans configured to introduce gas into one or more fluidized bed reactors when in use.

[0057] The system may include a solid inlet and a solid outlet. The system may be configured to move a solid adsorbent from the solid inlet along the length of one or more fluidized bed reactors to the solid outlet. One or more fans may be configured to move the solid adsorbent from the solid inlet along the length of one or more fluidized bed reactors to the solid outlet when in use. Optionally, one or more fans may be configured to gradually move the solid adsorbent from the solid inlet along the length of one or more fluidized bed reactors to the solid outlet.

[0058] The system may include one or more separation units through which, during use, the gas from which carbon dioxide has been removed is filtered. One or more separation units may be, or include, filters, bag filters, gas cyclones, or electrostatic precipitators (ESPs).

[0059] The system may be configured to bring a gas containing carbon dioxide into contact with a solid adsorbent at a temperature of 450°C to ambient temperature and a pressure of 1 to 1.5 bar during use.

[0060] The system may be configured to regenerate the solid adsorbent during use, thereby releasing carbon dioxide from the solid adsorbent and producing a concentrated carbon dioxide gas. The system may include a regeneration device for performing such regeneration. The system may include a second reactor configured to regenerate the solid adsorbent during use.

[0061] The system may be configured to regenerate the solid solvent by heating the solid adsorbent to a temperature of approximately 500–900°C during use. For example, the system may include a heat source for performing such heating.

[0062] The system may be configured to collect concentrated carbon dioxide gas during use. For example, the system may include a gas collector for performing such gas collection.

[0063] The system may be configured to reactivate the solid adsorbent upon use. The system may be configured to reactivate the solid adsorbent upon use in the presence of vapor at a temperature of approximately 900°C above ambient temperature. For example, the system may include a reactivation device for performing such reactivation.

[0064] The system may include a cooling device configured to cool the solid material when it leaves the reactor, preferably a calcining furnace reactor, and the cooling device may be configured to cool the solid material using a cooling gas when it leaves the reactor. The cooling device may be configured to transport the solid material in a countercurrent with the cooling gas. The cooling device may be configured to transport the solid material in a countercurrent with the cooling gas using gravity. The cooling device may be configured to transport the solid material in a direct or alternating current with the cooling gas.

[0065] The cooling device may include multiple cooling stages. The multiple cooling stages may include multiple parallel-arranged cooling stages configured to cool each portion of a solid material using a cooling gas during use. The multiple cooling stages may also include multiple sequentially arranged cooling stages configured to cool the solid material sequentially using a cooling gas during use.

[0066] The cooling device may include a hydration stage configured to hydrate a solid material during use. The hydration stage may be configured to receive solid material from one of a plurality of sequentially arranged cooling stages, and / or another cooling stage of the plurality of sequentially arranged cooling stages may be configured to receive solid material from the hydration stage during use.

[0067] The cooling system may include one or more fluidized bed coolers configured to cool a solid material using a cooling gas during use, wherein the cooling gas is a fluidizing gas. The one or more fluidized bed coolers may be in the form of multiple fluidized bed coolers arranged in parallel, or each fluidized bed cooler may include multiple fluidized bed cooler subunits. Fluidized bed coolers or fluidized bed cooler subunits may be stacked on top of each other to form a vertical stack of fluidized bed coolers or fluidized bed cooler subunits. Fluidized bed cooler subunits may be housed within the same enclosure as the corresponding fluidized bed cooler.

[0068] The cooling gas can be ambient air, without any limitations.

[0069] The cooling device may be configured to supply the cooled solid material to the reactor, preferably the carbonation reactor, when in use.

[0070] The system may include a heat exchanger configured to recover heat from the cooling of solid materials by a cooling device during use.

[0071] The system may include a heating device configured to heat the solid material using a heating gas before it enters a reactor, preferably a calcination furnace reactor, during use. The heating device may be configured to transport the solid material in a countercurrent with the heating gas. The heating device may be configured to transport the solid material in a countercurrent with the heating gas using gravity. The heating device may be configured to transport the solid material in a direct or alternating current with the heating gas.

[0072] The heating device may include multiple heating stages. The multiple heating stages may include multiple parallel heating stages configured to heat each portion of a solid material using a heating gas during use. The multiple heating stages may include multiple sequentially arranged heating stages configured to heat the solid material sequentially using a heating gas during use.

[0073] The heating device may include one or more fluidized bed heaters configured to cool a solid material using a heating gas during use, the heating gas being a fluidizing gas. The heating device may also include one or more cyclone flash heaters configured to heat a solid material using a heating gas during use. The one or more fluidized bed heaters may be in the form of multiple fluidized bed heaters arranged in parallel, or each fluidized bed heater may include multiple fluidized bed heater subunits. Fluidized bed heaters or fluidized bed heater subunits may be stacked on top of each other to form a vertical stack of fluidized bed heaters or fluidized bed heater subunits. Fluidized bed heater subunits may be housed within the same enclosure as the corresponding fluidized bed heater.

[0074] The heating device may be configured to receive the solid material to be heated from a reactor, preferably a carbonation reactor, during use.

[0075] The heating device may be configured to maintain the heating temperature of the solid material at a temperature of less than 550°C, preferably less than 500°C, during use.

[0076] The heating device may be configured to heat the heating gas using heat recovered from the cooling of the solid material by the cooling device during use.

[0077] Please understand that the use of terms such as “first” and “second” in this patent specification is intended solely to help distinguish similar features, and is not intended to indicate the relative importance of one feature to another unless otherwise indicated.

[0078] Within the scope of this application, the various aspects, embodiments, examples, and alternatives described in the preceding paragraphs, claims, and / or the following description and drawings, in particular their individual features, are expressly intended to be adopted independently or in any combination. That is, all embodiments and all features of any embodiment can be combined in any way and / or combination, except where such features are incompatible. The applicant reserves the right to modify any claim originally filed or to file any new claims accordingly. This includes the right to amend any claim originally filed to depend on and / or incorporate any feature of any other claim, even if it was not originally claimed as such.

[0079] The possibility of combining the optional and preferred features described above in any combination is within the scope of this disclosure.

[0080] This disclosure can be implemented in various ways, and examples of this disclosure will be described below with reference to the accompanying drawings. [Brief explanation of the drawing]

[0081] [Figure 1] This figure shows a schematic example of a fluidized bed reactor configured to carry out the method according to the present invention. [Figure 2] This figure shows a schematic example of a fluidized bed reactor and a calcination furnace reactor configured to carry out the method according to the present invention. [Figure 3] a is a photograph of a laboratory-scale fluidized bed apparatus configured to carry out the method according to the present invention. b is a diagram of the fluidized bed apparatus in a. [Figure 4] This figure shows how the concentration of carbon dioxide in the outlet gas stream changes over time as a result of the temperature change of a fluidized bed reactor obtained using the apparatuses in Figures 3a and 3b. [Figure 5] This figure shows the thermogravimetric analysis of a metal oxide adsorbent and a mixed metal oxide adsorbent. [Figure 6] This figure shows the thermogravimetric analysis of a metal oxide after five cycles of adsorbing carbon dioxide at 50°C and then regenerating it at 800°C. [Figure 7] This figure shows a typical fluidized bed reactor constructed according to the present invention. [Figure 8] This figure shows a typical electro-fluidized bed furnace system constructed according to the present invention. [Figure 9] This diagram shows an example of fluidized bed reactors arranged in parallel. [Figure 10] This figure shows another example of fluidized bed reactors arranged in parallel. [Figure 11] This is a diagram of a typical system including an integrated carbonation unit and firing furnace assembly. [Figure 12] Another diagram of a typical system including an integrated carbonation unit and firing furnace assembly. [Figure 13] This figure shows a typical layout of a system according to an embodiment of the present invention. [Figure 14] This figure shows another typical layout of the system according to an embodiment of the present invention. [Figure 15]This figure shows another typical layout of the system according to an embodiment of the present invention. [Figure 16] This figure shows another typical layout of the system according to an embodiment of the present invention. [Modes for carrying out the invention]

[0082] Next, a detailed description of exemplary methods and systems according to this disclosure for removing carbon dioxide from a gas is given with reference to the accompanying figures. While the exemplary methods and systems are described with reference to solid adsorbent mixtures and nanostructured adsorbents, they can also be applied to solid adsorbents and / or non-nanostructured adsorbents with necessary modifications.

[0083] Figure 1 illustrates reactor 1 of a system for removing carbon dioxide from a gas stream 2 by the method of the present disclosure. The gas stream is introduced into the reactor. The gas stream can be any gas stream containing carbon dioxide. For example, the gas can be air from the atmosphere, an exhaust gas stream from a power plant, or an exhaust gas stream from an industrial process. In particular, the gas stream may contain carbon dioxide at a concentration of 400–500 ppm (i.e., the current concentration of carbon dioxide in air from the atmosphere). The gas stream may be at ambient temperature and ambient pressure. In particular, the gas stream may be at a temperature of 450°C to ambient temperature and have a pressure of 1–1.5 bar. The temperature and pressure can be increased beyond these values. Increasing the temperature and pressure may increase the carbon dioxide recovery rate, but it will also increase the cost of the process as a result of heating and pressurizing the gas stream. The process can be used to remove carbon dioxide from gas streams with a carbon dioxide concentration higher than 400–500 ppm. For example, the process can be used to remove carbon dioxide from a gas stream where the carbon dioxide concentration is less than 1000 ppm, 800 ppm, 600 ppm, or 500 ppm. As the carbon dioxide concentration increases, it may be necessary to adjust the flow rate of the gas stream to ensure that the required amount of carbon dioxide is removed from the gas stream. The process is optimized to remove carbon dioxide from a gas stream that is atmospheric air, and therefore a gas stream with a carbon dioxide concentration of 400-500 ppm.

[0084] The reactor may be a fluidized bed reactor. Other reactor types may also be used. For example, a circulating fluidized bed reactor, or a swirling flow reactor, or a drop tube reactor, or a packed bed reactor, or a reactor cyclone.

[0085] A fluidized bed reactor can be a horizontal, rectangular fluidized bed reactor. The fluidized bed has length, width, and height. For example, the ratio of width to length of the fluidized bed reactor can be approximately 1:1 to 1:20. By using a horizontal fluidized bed reactor, large quantities of air can be processed without increasing the pressure drop of the gas introduced into the fluidized bed reactor. Horizontal fluidized bed reactors are preferred.

[0086] Gas stream 2 is introduced into reactor 1 using one or more external fans 3. Alternatively, gas streams may be introduced into the reactor using one or more blowers, compressors, etc. External fans, blowers, compressors, etc. may be arranged horizontally so that the gas is introduced at multiple locations along the length of the reactor. Alternatively, a single gas stream may be introduced using a single fan, compressor, blower, etc., and then this gas stream may be divided and introduced into reactor 1, so that only one means is required to introduce the gas stream. For example, if a fluidized bed reactor is used as reactor 1, the fluidized bed may have 1 to 10 (or more specifically 4 to 6) inlets for gas stream 2 (not shown in Figure 1). Different gas streams (or different parts of the same gas stream) may be configured so that there is a gradient in the gas stream velocity along the length of the fluidized bed reactor 1. The power consumption for the fans to blow gas through the reactor is given by Equation 1.

number

[0087] Upon entering the fluidized bed reactor 1, the gas stream can (optionally) pass through a gas distributor (e.g., a perforated distribution plate (not shown in FIG. 1)) to ensure a uniform distribution of the gas stream and a uniform gas velocity. The perforated distribution plate can cover the entire length of the fluidized bed reactor 1 or a number of individual distribution plates corresponding to the number of gas stream inlets can be used. Any other method for ensuring a uniform distribution of the gas stream through the reactor and a uniform gas velocity can be used. The gas stream enters the fluidized bed reactor 1 at the bottom or near the bottom of the fluidized bed reactor and passes upward through the fluidized bed reactor.

[0088] After passing through the perforated distribution plate, the uniformly distributed gas stream passes through a mesh / filter (not shown) in the fluidized bed reactor 1, where a stationary bed of solid adsorbent mixture floats. The size of the mesh / filter can be set so that the solid adsorbent mixture cannot fall through the mesh / filter, but the gas stream can pass through it. The mesh / filter can be made from any suitable material. The gas distributor ensures that the gas stream is fluidized and in uniform contact with the bed of solid adsorbent.

[0089] Solid adsorbent mixtures consist of solid adsorbents and may optionally contain a certain amount of silica. Solid adsorbent mixtures (mixtures containing solid adsorbents) may have an average particle size of less than 2500 microns. If present, silica is known to aid in the fluidization of solid adsorbents and is therefore useful. Solid adsorbents are mixtures of particles. Solid adsorbents may be mixed metal oxides or mixed metal hydroxides (which chemically react with carbon dioxide to form carbonated materials). Solid adsorbents are in the form of solid powders and may have an average particle size of 20 to 2000 microns. More preferably, the average particle size of the solid adsorbents in a solid adsorbent mixture may be 1000 to 2000 microns, and more preferably about 1500 microns. Solid adsorbent particles are nanostructures (as defined herein) and are not necessarily limited to nanoparticle sizes in terms of nominal particle size (i.e., not diameters of 1 to 100 nanometers), but the particles enclose a large internal surface area with three-dimensional porous structure properties at a nanostructure scale (about 1 to 100 nanometers) that provides surface area for the reaction to occur. Nanostructured solid adsorbent particles have a high internal surface area. For example, nanostructured solid adsorbents have an internal surface area of ​​approximately 1 to 200 m². 2 It can be / g. The high internal surface area of ​​solid adsorbents is achieved by the porosity of the adsorbent particles. Advantageously, by controlling the pore characteristics (e.g., the presence and number of mesopores and micropores, as well as the total internal surface area), rapid gas diffusion into the pores can be achieved while simultaneously achieving a fast reaction rate.

[0090] The metals in mixed metal oxides or mixed metal hydroxides may be selected from one or more of the following: calcium (Ca), magnesium (Mg), silicon (Si), aluminum (Al), iron (Fe), tungsten (W), manganese (Mn), copper (Cu), zinc (Zn), xanthine (Xo), strontium (Sr), cadmium (Cd), barium (Ba), and nickel (Ni). Ca adsorbs carbon dioxide (CO2), while the other metals may be inert or reactive to CO2, but may also provide structural stability to the adsorbent material, as well as resistance to wear and sintering. For example, the metals in a mixed metal oxide or mixed metal hydroxide may include calcium and one or more of magnesium (Mg), silicon (Si), aluminum (Al), iron (Fe), tungsten (W), manganese (Mn), copper (Cu), zinc (Zn), xanthine (Xo), strontium (Sr), cadmium (Cd), barium (Ba), and nickel (Ni). The nanostructured adsorbent may include one or more salts, hydroxides, nitrates, nitrites, or carbonates of lithium (Li), sodium (Na), and / or potassium (K). The nanostructured adsorbent may also include one or more of hydrogen bromide (HBr), hydrogen chloride (HCl), nitric acid (HNO3), and hydrogen iodide (HI).

[0091] Before gas is introduced into the fluidized bed reactor 1, the bed of solid adsorbent mixture is not fluidized, i.e., stationary on the mesh / filter. The stationary bed height is 0.5 to 20 cm, preferably 1 to 10 cm, more preferably 1 to 5 cm, and even more preferably 1 to 3 cm or 4 cm. By operating with a shallow bed height, the pressure drop across the bed can be minimized, demonstrating an effective amount of adsorbent mixture for removing carbon dioxide from a gas stream containing carbon dioxide while avoiding high energy requirements.

[0092] The introduction of gas stream 2 fluidizes the solid adsorbent mixture, causing it to behave like a turbulent fluid. This fluidization improves contact between the solid adsorbent mixture and the gas stream, increasing the rate of mass and heat transfer, and thus increasing the rate at which carbon dioxide is adsorbed by the solid adsorbent mixture.

[0093] When gas stream 2 comes into contact with the solid adsorbent mixture inside reactor 1, carbon dioxide is adsorbed from gas stream 2 onto the solid adsorbent mixture, and the solid adsorbent in the solid adsorbent mixture is carbonated. Due to the high rates of mass and heat transfer, most of the carbon dioxide can be removed from the gas by the solid adsorbent in a matter of seconds. The reaction (carbonation reaction) between the nanostructured metal hydroxide adsorbent and carbon dioxide produces metal carbonate and water according to equation 3. Equation 3: Me(OH)2 + CO2 → MeCO3 + H2O Here, Me(OH)2 is a metal hydroxide, CO2 is carbon dioxide, MeCO3 is a metal carbonate, and H2O is water.

[0094] After gas stream 2 comes into contact with the solid adsorbent mixture, a gas stream 5 from which carbon dioxide has been removed is produced and exits from the fluidized bed reactor 1. If atmospheric air is used as the gas stream, the gas stream from which carbon dioxide has been removed can be returned to the atmosphere. Alternatively, the gas stream from which carbon dioxide has been removed can be obtained for use elsewhere for heating, cooling, ventilation, oxidation, or other purposes, or sent for further processing.

[0095] Before being released into the atmosphere or further processing, the carbon dioxide-free gas stream 5 is passed through one or more gas-solid separation units 4 to remove any contaminating particles of the solid adsorbent mixture that may be suspended and separated in the carbon dioxide-free gas stream 5. The separation units 4 may be, for example, bag filters, cyclones, electrostatic precipitators (ESPs), or any combination thereof. This prevents particles of the solid adsorbent mixture from being contaminated and leaving the fluidized bed reactor with the carbon dioxide-free gas stream. One or more separation units 4 may be housed inside the fluidized bed reactor (e.g., in the case of bag filters), or one or more separation units may be located outside the fluidized bed reactor (e.g., in the case of cyclones or ESPs). Any other type of suitable separation unit may be used.

[0096] The carbonation reaction inside reactor 1 may take place in the presence of water, or a mixture of water and a low vapor pressure solvent. The inventors understand that the water or mixture of water and solvent forms a thin layer on the surface of the solid adsorbent mixture, thereby increasing the carbonation rate, which is a result of the liquid layer promoting the absorption and adsorption of carbon dioxide into the adsorbent. Water or a mixture of water and solvent can be introduced in many ways. For example, a certain amount of water, or a mixture of water and an organic solvent 6, may be introduced directly into the reactor. The solvent may be, for example, glycerol, liquid amine, and / or ionic liquid. The introduction of water into the reactor may be done, for example, using a sprayer, an internal spray nozzle, or a nebulizer, or other suitable equipment. Smaller droplets may be desirable because they increase the surface area for carbon dioxide absorption. Alternatively, the gas stream may be humidified, for example, by passing the gas stream through a water tank or other fluid. The gas stream may be humidified to about 100% H2O. Alternatively, the solid adsorbent mixture can be held under high humidity conditions for several minutes to several hours until it is almost completely hydrated before being exposed to the gas stream. The exact conditions will vary, for example, depending on the mass of adsorbent to be hydrated.

[0097] reproduction When the gas stream comes into contact with the solid adsorbent mixture and the solid adsorbent mixture becomes saturated with carbon dioxide, the solid adsorbent mixture needs to be replaced. This is because its ability to adsorb further carbon dioxide is limited, and in some cases, it may no longer be able to adsorb carbon dioxide from the gas stream. By creating a gradient in the gas stream velocity along the length of the fluidized bed reactor, the solid adsorbent mixture can be gradually moved from one side of the fluidized bed reactor (inlet side 7) to the other side (outlet side 8), with fresh solid adsorbent mixture added at the inlet side (i.e., continuous process). Alternatively, the solid adsorbent mixture can be moved from the inlet side to the outlet side using any suitable method. For example, a vibrating fluidized bed can be used to vibrate the mixture from the inlet side to the outlet side. After leaving the fluidized bed reactor, the solid adsorbent mixture is regenerated, i.e., the solid adsorbent is regenerated. Alternatively, the solid adsorbent mixture can be regenerated within the fluidized bed reactor (i.e., batch process). Regeneration involves heat treatment to break down the adsorbent components contained on the surface of the adsorbent.

[0098] Figure 2 shows an apparatus configured to send a solid adsorbent mixture to a second reactor (calcination furnace reactor 9), where it is heated (by a heat source 10) to release carbon dioxide from the solid adsorbent and regenerate it. Alternatively, the solid adsorbent mixture may be regenerated in a fluidized bed reactor. Heating of the solid adsorbent mixture can be carried out, for example, by a heater, microwave heating, electric heating, gas combustion heating, radiant heating, heating by a waste heat gas stream, or any other suitable method as the heat source 10. The solid adsorbent mixture is heated to about 500-900°C for about 1-60 minutes at ambient pressure.

[0099] When heated, carbon dioxide adsorbed on the solid adsorbent is released according to Equation 4. Equation 4 MeCO3+heat→MeO+CO2 Here, MeCO3 is a metal carbonate, MeO is a metal oxide, and CO2 is carbon dioxide.

[0100] The released carbon dioxide is removed from the calcination reactor 9 using a gas stream 11. The gas stream 11 is introduced into the calcination reactor 9 using one or more fans 12. Multiple gas streams 11 may be present. The gas stream may be a stream of carbon dioxide, steam, or a mixture of carbon dioxide and steam. The steam may be superheated using a superheater and / or an electric heat source (e.g., an electric heating coil) and / or a preheater.

[0101] The gas stream used to remove carbon dioxide from the calcination furnace reactor 9 is passed through one or more gas-solid separation units 13 to remove any contaminating particles of the solid adsorbent mixture. The gas-solid separation units may be, for example, bag filters or cyclone filters. The gas-solid separation units may be housed inside the calcination furnace (for example, in the case of bag filters), or one or more filters may be located outside the calcination furnace (for example, in the case of cyclone filters).

[0102] If the gas stream contains steam, it is cooled and condensed in the condenser 14 after regeneration to produce a water stream 15 and a stream of pure carbon dioxide 16. If the gas stream 11 used to remove carbon dioxide is pure carbon dioxide, neither cooling nor condensation is necessary. A heat exchanger may be used to recover the excess heat resulting from condensation. The recovered excess heat may be used in a heater (e.g., a superheater or preheater) to heat the gas stream 11 and / or the gas stream and / or steam for another reactor or apparatus.

[0103] A stream of pure carbon dioxide 16 can be compressed using a compressor 17 to produce a compressed stream of pure carbon dioxide 18. The stream of carbon dioxide 16 can be compressed to, for example, 100-150 bar. For example, a four-stage centrifugal compressor can be used to compress the carbon dioxide. The compressed carbon dioxide can be sequestrated for storage or use.

[0104] reactivation When carbon dioxide is desorbed from the solid adsorbent mixture, the nanostructured adsorbent is reactivated according to Equation 5. Formula 5 MeO+H2O→Me(OH)2+heat Here, MeO is a metal oxide, H2O is water, and Me(OH)2 is a metal hydroxide.

[0105] Steam 19 is used to reactivate the adsorbent and cool the adsorbent after the regeneration step. It is known that the steam creates a nanostructured reaction surface area on the metal hydroxide solid adsorbent, generating a hydrated material that increases the carbonation rate in the adsorption step. The reaction according to Equation 5 also generates heat, which can be recovered using a heat exchanger. The recovered heat can be used in a heater (e.g., a superheater or preheater) to heat the gas stream 11 and / or steam 19 and / or the gas stream for another reactor or apparatus and / or the steam for another reactor or apparatus. In this example, reactivation takes place in the same reactor as the regeneration of the solid adsorbent, although it is easily understood that a separate reactor could be used for the reactivation of the adsorbent. The reactivation reaction between steam 19 and the solid adsorbent can take place at a temperature of ~900°C above ambient temperature. The temperature is chosen to ensure the mechanical stability and reactivity of the solid adsorbent particles.

[0106] Since the desorption rate in the regeneration step is faster than the adsorption rate, a mixture of solid adsorbents from multiple fluidized bed reactors can be supplied into a single calcination furnace 9.

[0107] Once the solid adsorbent mixture is regenerated and reactivated, it can be recycled and added back into the fluidized bed reactor to remove more carbon dioxide from the gas stream.

[0108] Other methods may also be used to reactivate the adsorbent. For example, the carbonation reaction can, in some cases, be carried out for longer than originally required, resulting in the solid adsorbent being carbonated in excess of the normal amount during the cycle. In this type of long carbonation cycle, the material is found to become denser than in the case of the usual short cycle, and as a result, when the material is subsequently calcined in the regeneration step, the released CO2 molecules are thought to leave behind new and / or renewed internal pore space and reaction surface area. Thus, when solid adsorbents are regenerated in this manner, it is advantageous that more effective pore space and reaction surface area are available compared to unregenerated adsorbents, as well as compared to the original fresh adsorbent material.

[0109] Alternatively, the solid adsorbent can be rapidly heated in the presence of a gas stream during the firing step. As a result, CO2 and H2O molecules are rapidly released / explode from the solid particles of calcium carbonate and calcium hydroxide, forming a reaction region inside.

[0110] A series of sensors are used to monitor temperature, pressure, humidity, gas velocity, gas concentration, gas flow rate, and other parameters inside the reactor. This is done both before entering one or more reactors and after leaving one or more reactors.

[0111] The system of the present invention may include an integrated humidity control system for the supply air, thereby the system may include one or more of the following: • Relative humidity sensor (e.g., hygrometer) in the supply duct, • Humidifiers for humidifying the surrounding air (e.g., air sprayers) • Dust collector (for example, a dust collection cyclone).

[0112] The fluidized bed reactor and calcination furnace can be housed in either a 20-foot or 40-foot shipping container.

[0113] experiment Figure 3a shows a photograph of a laboratory-scale fluidized bed reactor used to remove carbon dioxide from ambient air using an adsorbent by the method described herein. Figure 3b shows a piping and instrumentation diagram (P&ID) of the apparatus in Figure 3a.

[0114] The fluidized bed reactor shown in Figure 3a was made of quartz and had an inner diameter of 15 mm. A thermocouple was attached to the fluidized bed reactor to allow for in-situ temperature measurement during the experiment. The inlet of the fluidized bed reactor could be used to introduce 170°C steam, ambient air, and / or nitrogen into the reactor and pass it through the adsorbent bed using an external mass flow controller (Bronkhurst MFC). The inventory of adsorbent bed used in each experiment (i.e., the amount of adsorbent used) was approximately 2.5–3 ml, and the height of the non-fluidized adsorbent bed was approximately 11–13 mm. Steam was generated using a water pump. The fluidized bed reactor is used for both carbonation and calcination reactions. A quartz filter is attached to the outlet of the fluidized bed reactor and is designed to remove any suspended adsorbent material from the outlet gas. After passing through the filter, the outlet gas is cooled using an ice bath and then sent to a gas analyzer.

[0115] Figure 4 shows experimental data obtained using the apparatus shown in Figures 3a and 3b. Figure 4 shows how the concentration of carbon dioxide in the outlet gas changes over time in response to changes in the operating temperature of the reactor. The fluidized bed was initially filled with Havelock limestone as an adsorbent material in the form of metal carbonates containing nanostructures (nanostructure adsorbents) as defined herein, obtained, for example, by calcination under fluidization conditions. The particle size of the adsorbent material was set to 250-425 μm.

[0116] At time 0 minutes, the temperature inside the reactor is the ambient temperature, and the carbon dioxide concentration is close to what is expected in the ambient air (i.e., 400 ppm). This stage is shown as Stage (1) in Figure 4. During Stage (2), the ambient airflow is replaced with nitrogen, reducing the carbon dioxide concentration to approximately 0 ppm. Simultaneously, the reactor system is heated to 800°C, causing a rapid increase in the carbon dioxide concentration in the outlet gas as carbon dioxide is released from the adsorbent material. The carbon dioxide concentration eventually returns to near 0 ppm as all the carbon dioxide is released from the adsorbent material and the reactor system temperature returns to ambient temperature. In Stage (3), the nitrogen flow through the fluidized bed reactor is replaced with ambient air. When the air comes into contact with the adsorbent material, the temperature inside the reactor rises slightly as a result of the exothermic carbonation reaction. The carbon dioxide concentration in the outlet gas remains at approximately 0 ppm because the carbon dioxide is adsorbed by the adsorbent material, indicating that carbon dioxide has been almost completely removed from the ambient air at the inlet. In stage (4), the gas sampling line (via filter, ice bath, and pump) that was ultimately connected to the CO2 analyzer was removed from the reactor, and the concentration of carbon dioxide under ambient conditions was measured to confirm the initial measurements from stage (1). In stage (5), the temperature inside the reactor was raised to approximately 800°C, releasing the carbon dioxide adsorbed by the adsorbent during stage (3) and regenerating the adsorbent. The ambient air and / or nitrogen flow rate during the process shown in Figure 4 was maintained at 700 ml / min. It has been found that when using particle sizing in the range of 500–710 μm for the adsorbent material, a higher flow rate of air and / or nitrogen of 1000 ml / min should be used.

[0117] Figure 5 shows the results of thermogravimetric analysis performed on two adsorbent materials using the reactor apparatus shown in Figures 3a and 3b. One adsorbent was a metal oxide adsorbent (Hablock limestone), and the other was a mixed metal oxide adsorbent (a synthetic mixed metal oxide adsorbent containing 85% Ca and 15% Mg). The mixed metal oxide adsorbent used was synthesized by treating aqueous solutions of xylose, urea, and glycine with calcium and magnesium precursors in hot water at 180°C for 24 hours, simultaneously hydrolyzing the urea to precipitate a mixture of CaCO3 and MgCO, followed by calcination in air at 800°C to remove the carbonaceous template and form nanostructured pores inside. Both adsorbents were in the form of fine powder (<50 μm).

[0118] Figure 5 shows the temperature dependence and normalized weight of the mixed metal oxide adsorbent and the metal oxide adsorbent. A thermogravimetric analyzer was used to measure the change in the normalized weight of the adsorbent (resulting from calcination, hydration, and carbonation of the adsorbent). At the start of the experiment, the fluidized bed was initially filled with a carbonate-type adsorbent.

[0119] Between 0 and 50 minutes, the reactor temperature is raised from ambient temperature to 800°C, calcining the carbonated metal adsorbent and releasing carbon dioxide, reducing its normalized weight to approximately 0. The reactor temperature is then lowered to 50°C in approximately 100 minutes. Between 100 and 400 minutes, humid ambient air passes through the fluidized bed, increasing the weight of the metal oxide through a combination of carbonation and hydration. At 400 minutes, the air is replaced with nitrogen, and the reactor temperature is raised from ambient temperature to 800°C. During this temperature increase, three distinct stepwise changes occur in the normalized weight of the metal oxide. The first is the result of evaporation of excess water in the adsorbent; the second is the result of dehydration of water chemically bound to the adsorbent material; and the third is the result of desorption of carbon dioxide from the adsorbent. These three stage-like changes are shown in Figure 5 as stages (1), (2), and (3). As is clear from Figure 5, the mixed metal oxide adsorbent shows a significant improvement in carbonation capacity (>10%) compared to the metal oxide adsorbent.

[0120] Figure 6 shows the temperature change and normalized weight of a metal oxide adsorbent (Hablock limestone, particle size <50 μm) during repeated cycles of calcination and carbonation of the adsorbent material. At time 0 minutes, the temperature in the reactor was raised to approximately 800°C, and nitrogen was supplied to the reactor. The normalized weight of the metal oxide adsorbent decreased to 0. Next, the temperature in the reactor was lowered, and the nitrogen was replaced with ambient air. As the adsorbent adsorbed carbon dioxide, the normalized weight of the metal oxide increased to approximately 0.4. This calcination and carbonation cycle was repeated four more times. In the final cycle, the normalized weight of the metal oxide increased to approximately 0.35. This indicates that the adsorbent material is relatively chemically stable and has a large CO2 adsorption capacity.

[0121] Examples of non-limiting embodiments of the present invention and its features are described below, which may be implemented in any embodiment of the present invention described herein, as part thereof, or in combination therewith.

[0122] Figure 7 shows a typical horizontal stationary fluidized bed reactor 20 for recovering carbon dioxide from air. The fluidized bed reactor 20 is suitable for use with various nanostructured adsorbents, particularly calcium oxide and calcium carbonate. In a preferred embodiment, the fluidized bed reactor 20 has a total capacity of 29 m³ via a gas distributor plate. 2 The fluidization area and the 1600 m² allow for an air velocity of 1.5 m / s through the fluidized bed surface. 2 It has a filtration area. Dividing plates are provided between the drying areas of the drying section. An overflow weir (e.g., a pneumatically operated overflow weir) is provided at the end of the drying section. The thickness of the product layer can be adjusted by manually changing the height of the weir when the fluidized bed reactor 20 is offline. An airlock valve (e.g., a rotary airlock valve) may be installed at the inlet of the fluidized bed reactor.

[0123] Optionally, the fluidized bed reactor 20 includes a separation unit in the form of an exhaust gas filter 22 integrated into the suction hood. This separation unit can be operated to retain fine product particles inside the fluidized bed reactor 20. Preferably, the exhaust gas filter 22 is a pulse jet filter. As mentioned above, the filtration area of ​​the filter 22 is typically 1600 m². 2 The bag filter of filter 22 may be made of fabric (for example, polyester needle felt). The fluidized bed reactor 20 may include one or more exhaust fans 24 (for example, centrifugal fans) connected to the exhaust gas filter 22 by a duct structure. The one or more exhaust fans 24 are configured to direct the exhaust gas from the exhaust gas filter 22 to one or more discharge ports 26 (for example, a chimney).

[0124] Figure 8 shows a typical electro-fluidized bed furnace system.

[0125] The firing furnace system includes an electric heating jacket 28 wrapped around the firing furnace reactor 30. Optionally, the electric heating jacket 28 may be configured to heat different zones of the firing furnace reactor 30 separately at different temperatures, thereby creating a temperature gradient within the firing furnace reactor 30. The electric heating jacket 28 may be replaced with different types of heaters.

[0126] The calcination furnace system further includes an inlet gas distributor (e.g., an inlet gas distribution nozzle), a filter 32 (e.g., a high-temperature metal filter), and a steam heater 34 (e.g., a steam superheater). The filter 32 is configured as a separation unit for removing solid particles from the exhaust gas exiting the calcination furnace reactor 30. High-temperature CO2 exits from the bottom of the filter 32. The steam heater 34 is in the form of a once-through boiler that recovers heat from the calcination furnace exhaust gas, thereby cooling the calcination furnace exhaust gas. The recovered heat can be used to boil water entering the steam heater 34 at ambient temperature, thereby generating steam, which can be used as a fluidizing gas inside the calcination furnace reactor 30 or in another reactor or apparatus.

[0127] The calcination furnace system further includes an internal gas-solid heat exchanger 36 (e.g., a coil / solid air transport tube) located inside and near the bottom of the calcination furnace reactor. A solid adsorbent material (e.g., a mixture of calcium carbonate and calcium hydroxide) enters the calcination furnace reactor 30 preferably through a supply port 38 located inside or near the ceiling of the calcination furnace reactor 30, while metal oxides from the regeneration process exit the calcination furnace reactor 30 preferably through an outlet 40 located inside / near the bottom of the calcination furnace reactor. Preferably, the calcination furnace reactor 30, filter 32, and steam heater 34 are partially or completely enclosed with insulating material to minimize heat loss and limit surface temperature.

[0128] The firing furnace in embodiments of the present invention may be a rotary firing furnace (e.g., a rotary kiln). That is, a rotary firing furnace can replace a fluidized bed firing furnace. The rotary firing furnace may include, for example, one or more of the following: a rotary firing furnace shell, a furnace (e.g., an electric heating furnace, optionally having a nominal capacity of 330 kW or 550 kW), internal insulation (e.g., ceramic fiber insulation), a high-temperature heating element, multi-zone temperature control, and heat-retaining end seals (e.g., ceramic fiber tadpole end seals). The drive system for the rotary firing furnace may include a chain drive system, an auxiliary drive unit, and a mechanical gear reducer.

[0129] Preferably, the firing furnace in the embodiment of the present invention may interact with, combine with, or integrate with an additional heat exchanger system for preheating the low-temperature solid entering the firing furnace and cooling (and recovering heat from) the high-temperature solid exiting the firing furnace.

[0130] Figures 9 and 10 preferably show examples of parallel-arranged fluidized bed subunits 41 of a fluidized bed reactor for use as a carbonation device in the system of the present invention. In embodiments of the present invention, a gas containing carbon dioxide 42 is distributed to flow in parallel through the parallel-arranged fluidized bed subunits 41 and come into contact with a solid adsorbent mixture 44 in a plurality of parallel-arranged fluidized bed subunits 41. Each portion of the gas containing carbon dioxide 42 comes into contact with the solid adsorbent mixture 44 in each of the plurality of parallel-arranged fluidized bed subunits 41 (preferably simultaneously). In the illustrated embodiments, the fluidized bed subunits 41 are housed within the same enclosure of the fluidized bed reactor. Each fluidized bed subunit 41 is associated with its own gas distributor (e.g., gas distributor plate), through which the gas is introduced into the fluidized bed subunit 41.

[0131] Preferably, the fluidized bed subunits 41 are stacked on top of each other to form a vertical stack of fluidized bed subunits 41, but in other embodiments, the stack of fluidized bed subunits 41 may be substantially or nearly vertical. In other embodiments, the fluidized bed subunits 41 may be arranged on different vertical planes at different heights so that they do not stack on top of each other. In yet another embodiment, the fluidized bed subunits 41 may be arranged in the same horizontal plane.

[0132] It will be understood that the fluidized bed subunits 41 arranged in parallel may form an integrated arrangement, array, or stack of fluidized bed subunits 41, or they may be in the form of modules that can be freely assembled and disassembled to form different layouts and / or different numbers of modules, depending on the system performance and installation area requirements.

[0133] The fluidized bed subunits 41, arranged in parallel, may share the same gas inlet 46 (Figure 9), or in other embodiments, each may have its own individual gas inlet. The fluidized bed subunits 41 may share the same gas outlet 48 (Figure 9), or in other embodiments, each may have its own individual gas outlet.

[0134] The fluidized bed subunits 41 arranged in parallel may share the same solid inlet for supplying solid material, or each may have its own separate solid inlet 47 (Figure 10). The fluidized bed subunits 41 arranged in parallel may share the same solid outlet 49 for discharging solid material (Figure 10), or each may have its own separate solid outlet.

[0135] By vertically stacking gas containing carbon dioxide 42 through parallel-arranged fluidized bed subunits 41, the pressure drop across each fluidized bed subunit 41 is equal (reducing fan power costs), while ensuring an increase in gas volume throughput and consequently an increase in the amount of CO2 recovered relative to a given reactor size and footprint. This improves carbonation efficiency and reduces the overall size and material requirements of the carbonator while maintaining the necessary performance, thus reducing the overall capital investment requirements for the system.

[0136] Furthermore, the parallelism of the fluidized bed subunits 41 allows for scaling the capacity of the carbonation unit by adding fluidized bed subunits vertically and / or laterally. This scaling flexibility enables easy deployment and installation of the system to meet various locations and application requirements.

[0137] In an alternative embodiment, instead of the parallel-arranged fluidized bed subunits 41, multiple parallel-arranged fluidized bed reactors, which are separate units from one another, may be used.

[0138] In embodiments of the present invention, the system may include a heat recovery mechanism (particularly for recovering heat from a high-temperature solid leaving a reactor (e.g., a calcination furnace) and using the recovered heat to heat a low-temperature solid before it enters the reactor (e.g., a calcination furnace)).

[0139] The system may include an airflow circuit that includes a driven fan for circulating air as a heat transfer medium between the heat exchanger fluidized beds.

[0140] The system may include a cooling device, for example, in the form of a hydration chamber, preferably with a fluidized bed reactor design, more preferably with a counterflow (and / or direct-to-alternating) arrangement of solids and gases to maximize heat recovery efficiency. The hydration chamber is connected (preferably integrally) to the inlet to the carbonator. The hydration chamber may include a water spray for hydrating and cooling the incoming material. The hydration chamber is configured to discharge the cooled solid material into the carbonator. An airlock (e.g., a mechanical rotary airlock) may be used to control the discharge of material into the carbonator and prevent the release of vapors from the hydration chamber, while maintaining a secure gas seal between the hydration chamber and the carbonator. The solid material may exit the hydration chamber through an overflow weir, and there may also be a manual underflow gate for discharging material during cleaning. The hydration chamber is preferably made of a material that can withstand high temperatures (e.g., stainless steel) and may be surrounded by insulation.

[0141] The system may include a heating device, for example, in the form of a preheating chamber, preferably a fluidized bed reactor design, more preferably a counterflow (and / or direct-to-alternating) arrangement of solid and gas to maximize heat recovery efficiency. The solid is preheated using a hot gas, which may be removed from the exhaust of the hydration chamber. The cooled exhaust gas from the preheating chamber may optionally be used as a fluidizing gas in the hydration chamber. The preheating chamber is preferably made of a material that can withstand high temperatures (e.g., stainless steel) and may be surrounded by insulation.

[0142] The system may include both a cooling device and a heating device.

[0143] Figures 11 and 12 show a typical system including an integrated carbonation and firing furnace assembly. The assembly includes a carbonation unit 50, a firing furnace 52, a preheater 54, and a hydration chamber 56. The carbonation unit 50 is a single-plate fluidized bed reactor, while the firing furnace 52 is an electro-fluidized bed reactor. The fluidizing gas used in the firing furnace 52 may be in the form of steam that can be heated by a superheater, which may use heat recovered from the exhaust 58 of the hydration chamber 56. The preheater 54 is configured to heat the solid material before it is supplied to the firing furnace 52. The hydration chamber 56 is configured to hydrate and cool the solid material received from the firing furnace 52 by gravity supply. The hydration chamber 56 is configured to discharge the cooled solid material to the carbonation unit 50 by gravity supply. In the illustrated embodiment, the hydration chamber 56 is integrally connected between the firing furnace 52 and the carbonation unit 50.

[0144] The cooling system may be configured to include a plurality of parallel or sequentially arranged cooling stages for cooling a solid material. Each cooling stage may have a fluidized bed reactor design. For example, the cooling system may include a plurality of vertically and sequentially arranged cooling stages, thereby moving the solid material (e.g., from a calcination furnace) downward (e.g., by gravity) from the upper cooling stage chamber through the intermediate cooling stage chamber(s) to the lower cooling stage chamber, while the cooling gas flows upward from the lower cooling stage chamber through the intermediate cooling stage chamber(s) to the upper cooling stage chamber. In a typical embodiment, the upper cooling stage(s) may reduce the temperature of the solid material coming out of the calcination furnace reactor from 850°C to 100°C. In the next cooling stage(s), water (e.g., using a sprayer or atomizer) is introduced to hydrate the solid material and generate heat, raising its temperature to about 300°C. Next, in the remaining cooling stages, the solid material is cooled to near ambient temperature before entering the carbonation reactor. The fluidizing gas that enters the lower cooling stage and moves upward along the cooling stage chain is ambient air, and its temperature rises to nearly 750-800°C towards the end of the cooling stage chain. It should be understood that the temperatures described are merely illustrative to illustrate the operating principle of this embodiment.

[0145] The heating apparatus may be configured to include multiple parallel or sequentially arranged heating stages for heating solid materials. Each heating stage may have a fluidized bed reactor design or a flash cyclone design. For example, the heating apparatus may include multiple vertically and sequentially arranged heating stages, thereby moving the solid material (e.g., from a carbonation apparatus) downward (e.g., by gravity) from the upper heating stage chamber through the intermediate heating stage chamber(s) to the lower heating stage chamber, while the heating gas flows upward from the lower heating stage chamber through the intermediate heating stage chamber(s) to the upper heating stage chamber. In a typical embodiment, the low-temperature solid from the carbonation apparatus enters the upper heating stage and is heated in countercurrent with the heating gas flowing through the heating stage, the heating gas may originate from a cooling stage. The solid material exits the lower heating stage at a temperature of about 500–550°C before entering the carbonation reactor. The hydroxide material is dehydrated and releases vapor. The steam can be recycled into a cooling or hydration device (for example, the examples described throughout the specification). The temperature in the heating device is kept below 550°C, preferably below 500°C, to prevent calcination and thus the production of the desired CO2 product. 2。 This prevents it from being released into the air stream and wasted.

[0146] The number of cooling and / or heating stages may be configured to provide high cooling / heating throughout in order to achieve a high heat recovery rate. The system may include one or more passive flow controllers (e.g., mechanical deflectors or guide channels) or one or more active flow controllers (e.g., fans) to guide the gas to flow in parallel through the cooling stages arranged in parallel.

[0147] The counterflow and staged configuration improves heat recovery compared to a single-stage equilibrium fluidized bed reactor, thus achieving high heat recovery efficiency while recovering the heat of hydration, and reducing the electrical load on the calcination furnace.

[0148] Figure 13 shows a typical system based on a calcination furnace with a fluidized bed reactor design. The system includes a carbonation unit 60, a calcination furnace 62, and a hydration chamber 64.

[0149] The solid adsorbent mixture is supplied from the adsorbent supply source 61 to the adsorbent hopper 66 and stored there. When the required amount of solid adsorbent mixture is filled into the adsorbent hopper 66, the supply of the solid adsorbent mixture may be stopped. The adsorbent hopper 66 may be replenished with additional solid adsorbent mixture as needed.

[0150] Air (i.e., gas containing carbon dioxide) is supplied using the carbonation inlet fan 68 to provide fluidized gas to the carbonation unit 60. Droplet water may be added to the air, for example, using a sprayer or spray 70. The water may be supplied from a tap water source 63, or optionally from a condensate return 65.

[0151] The adsorbent hopper 66 dispenses a controlled amount of solid adsorbent mixture onto a screw conveyor 72. The solid adsorbent mixture is then transferred by the screw conveyor 72 to an adsorbent heater 74, through a calcination furnace 62, and then to an adsorbent cooler 76 (or it may be transferred directly to the adsorbent cooler 76 by the screw conveyor 72). The solid adsorbent mixture is hydrated using a hydration chamber 64 before being transferred into the carbonation unit 60. Inside the carbonation unit 60, a fluidizing gas is brought into contact with the solid adsorbent mixture. The carbonation unit 60 then outputs the solid adsorbent mixture onto a conveyor belt 78, which returns the solid adsorbent mixture to the adsorbent hopper 66.

[0152] Water is supplied to the hydration chamber 64 from a tap water source 63, or optionally from a condensate return 65. Air is supplied using a hydrator fan 80, providing a fluidizing gas to the hydration chamber 64. Droplet water can be added to the air, for example, using a sprayer or spray 70. Water can be sourced from a tap water source 63, or optionally from a condensate return 65.

[0153] The solid adsorbent mixture in the adsorbent hopper 66 is brought into contact with a gas containing carbon dioxide and then transported to the adsorbent heater 74 for preheating before entering the calcination furnace 62. The heating gas for the adsorbent heater 74 can be taken from the exhaust of the hydration chamber 64 and / or the cooling device 76. Steam heated by the steam superheater 82 is supplied to the calcination furnace 62 as a fluidizing gas. Water for the steam can be supplied by a water source 63 and optionally by a condensate return 65. The water may pass through a boiler 84 that recovers heat from the exhaust gas leaving the calcination furnace 66. A separation unit 86 separates the exhaust from the calcination furnace and the boiler.

[0154] Next, the regenerated solid adsorbent mixture is transported from the calcination furnace 62 to the adsorbent cooling unit 76 and the hydration chamber 64, where it is hydrated and cooled before being transported to the carbonation unit 60.

[0155] Figures 14, 15, and 16 show alternative layouts for the system of the present invention, which are based in particular on a firing furnace 88 having an electric rotary kiln firing furnace design. The components of the systems in Figures 14, 15, and 16 are similar in structure and operation to the corresponding components of the system in Figure 13, and similar features share the same reference numerals. Additional components may include one or more of the following: a carbon dioxide cooler 90, a condensate knockout drum 92, a circulation fan 94, and a carbonation unit outlet fan 96. In Figure 14, the cooled exhaust gas from the adsorbent heater 76 may optionally be used as a fluidizing gas in a hydration chamber, thereby the cooled exhaust gas may be circulated using the circulation fan 94, to which water may be added. In Figure 16, the carbonation unit 98 is based on an arrangement of fluidized bed reactors arranged in parallel, examples of which are described throughout the specification.

[0156] The numerical values ​​used in the description and drawings are intended solely to aid in explaining the operation of the present invention and are to be understood to vary depending on the requirements of the invention and its associated applications.

[0157] In this specification, the listing or description of documents or information that are clearly previously published should not be construed as an endorsement that the documents or information are part of the prior art or common general knowledge.

[0158] Priorities and alternatives to any given aspect, feature, or parameter of the present invention may be considered to be disclosed in conjunction with all other priorities and alternatives to any other aspect, feature, and parameter of the present invention, unless otherwise indicated by the context.

Claims

1. A method for removing carbon dioxide from a gas containing carbon dioxide, wherein the method is The process includes contacting the gas containing carbon dioxide with a fluidized solid adsorbent to remove carbon dioxide from the gas and form a gas from which carbon dioxide has been removed. method.

2. The method according to claim 1, wherein the gas containing carbon dioxide is brought into contact with the solid adsorbent in the presence of water or one or more solvents, or a mixture of water and one or more solvents.

3. The method according to claim 2, wherein the water is provided by humidifying the gas containing carbon dioxide to about 100% humidity, or by passing the gas containing carbon dioxide through water and creating bubbles before bringing it into contact with the solid adsorbent.

4. A method according to any one of claims 1 to 3, wherein the gas containing carbon dioxide is brought into contact with the solid adsorbent in one or more reactors.

5. A method according to claim 4, wherein the one or more reactors are one or more fluidized bed reactors.

6. The method according to claim 5, wherein the one or more fluidized bed reactors have an aspect ratio of width to length in the range of 1:1 to 1:20, preferably 1:5, and more preferably 1:

3.

7. The method according to claim 5 or 6, wherein the gas containing carbon dioxide is brought into contact with the solid adsorbent in each of the multiple fluidized bed reactors arranged in parallel.

8. The method according to claim 7, wherein the fluidized bed reactors are stacked on top of each other to form a vertical stack of fluidized bed reactors.

9. The method according to any one of claims 5 to 8, wherein the one or more fluidized bed reactor includes a plurality of fluidized bed subunits arranged in parallel, and the gas containing carbon dioxide is in contact with the solid adsorbent in each of the plurality of fluidized bed subunits arranged in parallel.

10. The method according to claim 9, wherein the fluidized bed subunits are stacked on top of each other to form a vertical stack of fluidized bed subunits.

11. The method according to any one of claims 5 to 10, wherein one or more gas distributors are provided, and the gas is introduced to the one or more fluidized bed reactors through them.

12. The method according to any one of claims 5 to 11, wherein one or more fans are provided to introduce the gas into the one or more fluidized bed reactors.

13. The method according to any one of claims 5 to 12, wherein the solid adsorbent is moved from the solid inlet to the solid outlet along the length of the one or more fluidized bed reactors.

14. The method according to claim 13, as dependent on claim 12, wherein one or more fans are configured to move the solid adsorbent from the solid inlet to the solid outlet along the length of the one or more fluidized bed reactors, and optionally, one or more fans are configured to gradually move the solid adsorbent from the solid inlet to the solid outlet along the length of the one or more fluidized bed reactors.

15. The method according to any one of claims 5 to 14, wherein one or more separation units are provided, and the gas from which the carbon dioxide has been removed is filtered through them.

16. The method according to claim 15, wherein the one or more separation units are or include a filter, a bag filter, a gas cyclone, or an electrostatic precipitator (ESP).

17. The method according to any one of claims 1 to 16, wherein the gas containing carbon dioxide is brought into contact with the solid adsorbent at a temperature of 450°C to ambient temperature and a pressure of 1 to 1.5 bar.

18. The method according to any one of claims 1 to 17, further comprising the step of regenerating the solid adsorbent, thereby releasing carbon dioxide from the solid adsorbent and generating a concentrated carbon dioxide gas.

19. A method according to claim 18, wherein the solid adsorbent is regenerated in a second reactor or kiln.

20. A method according to claim 18 or 19, wherein the solid adsorbent is regenerated by heating the solid adsorbent to a temperature of about 500 to 900°C.

21. The method according to any one of claims 18 to 20, further comprising the step of collecting the concentrated carbon dioxide gas.

22. The method according to any one of claims 18 to 21, further comprising the step of reactivating the solid adsorbent.

23. A method according to claim 22, wherein the solid adsorbent is reactivated in the presence of vapor at a temperature of ambient temperature to 900°C.

24. A method according to any one of claims 1 to 23, wherein the gas containing carbon dioxide is air in the atmosphere.

25. A method according to any one of claims 1 to 24, wherein the gas containing carbon dioxide has a carbon dioxide concentration of less than 1,000 ppm, more preferably less than 800 ppm, more preferably less than 600 ppm, and more preferably less than 500 ppm.

26. A method according to any one of claims 1 to 25, wherein the solid adsorbent comprises particles of the solid adsorbent, optionally comprising silica particles, and the average particle size of the solid adsorbent and silica particles is less than 2500 microns.

27. The average particle size of the solid adsorbent is 20 to 2000 microns, and its internal surface area is 1 to 200 m². ２ The method according to any one of claims 1 to 26, wherein the value is / g.

28. The method according to any one of claims 1 to 27, wherein the solid adsorbent is a mixed metal oxide or mixed metal hydroxide, and the metal oxide or metal hydroxide comprises one or more of Ca, Mg, Si, Al, Fe, W, Mn, Cu, Zn, Xo, Sr, Cd, Ba, and Ni.

29. The method according to claim 28, wherein the solid adsorbent comprises a mixed metal oxide or mixed metal hydroxide, the mixed metal oxide or mixed metal hydroxide comprises Ca, and optionally further comprises one or more of Mg, Si, Al, Fe, W, Mn, Cu, Zn, Xo, Sr, Cd, Ba, and Ni.

30. The solid adsorbent comprises one or more salts of Li, Na, and / or K, hydroxides, nitrates, nitrites, and / or carbonates, and HBr, HCl, HNO ３ The method according to any one of claims 1 to 29, comprising, and any combination of HI.

31. The method according to any one of claims 1 to 30, wherein the solid adsorbent is Havelock limestone or a mixed metal oxide containing 85 wt% Ca and 15 wt% Mg.

32. The method according to any one of claims 1 to 31, comprising the step of cooling a solid material that has exited a reactor, preferably a calcining furnace reactor, wherein the solid material is cooled using a cooling gas.

33. The method according to claim 32, further comprising the step of transporting the solid material in the countercurrent with respect to the cooling gas.

34. The method according to claim 33, comprising the step of using gravity to transport the solid material in a countercurrent with the cooling gas.

35. The method according to claim 32, further comprising the step of transporting the solid material with respect to the cooling gas in a direct or alternating current.

36. The method according to any one of claims 32 to 35, further comprising the step of cooling the solid material in a plurality of cooling stages.

37. The method according to claim 36, wherein the plurality of cooling stages include a plurality of parallel-arranged cooling stages configured to use the cooling gas to cool each portion of the solid material when in use.

38. The method according to claim 36 or 37, wherein the plurality of cooling stages include a plurality of sequentially arranged cooling stages configured to sequentially cool the solid material using the cooling gas during use.

39. The method according to any one of claims 32 to 38, comprising the step of hydrating the solid material.

40. The method according to claim 38 or 39, comprising the steps of hydrating the solid material received from one of the plurality of sequentially arranged cooling stages, and / or hydrating the solid material and providing the hydrated material to another cooling stage of the plurality of sequentially arranged cooling stages.

41. The method according to any one of claims 32 to 40, comprising the step of cooling the solid material using the cooling gas, wherein the cooling gas is a fluidizing gas, using one or more fluidized bed coolers.

42. The method according to any one of claims 32 to 41, wherein the cooling gas is ambient air.

43. The method according to any one of claims 32 to 42, comprising the step of supplying the cooled solid material to a reactor, preferably a carbonation reactor.

44. The method according to any one of claims 32 to 43, comprising the step of recovering heat from the cooling of the solid material.

45. The method according to any one of claims 1 to 44, comprising the step of heating a solid material using a heating gas before the solid material enters a reactor, preferably a calcination furnace reactor.

46. The method according to claim 45, further comprising the step of transporting the solid material in a countercurrent with respect to the heated gas.

47. The method according to claim 46, comprising the step of transporting the solid material in a countercurrent with respect to the heated gas using gravity.

48. The method according to claim 45, further comprising the step of transporting the solid material with respect to the heating gas in a direct or alternating current.

49. The method according to any one of claims 45 to 48, comprising the step of heating the solid material in a plurality of heating stages.

50. The method according to claim 49, wherein the plurality of heating stages include a plurality of parallel-arranged heating stages configured to heat each portion of the solid material using the heating gas when in use.

51. The method according to claim 49 or 50, wherein the plurality of heating stages include a plurality of sequentially arranged heating stages configured to sequentially heat the solid material using the heating gas during use.

52. The method according to any one of claims 45 to 51, comprising the step of using one or more fluidized bed heaters to cool the solid material using the heating gas, wherein the heating gas is a fluidizing gas.

53. The method according to any one of claims 45 to 52, comprising the step of heating the solid material using the heating gas with one or more cyclone flash heaters.

54. The method according to any one of claims 45 to 53, comprising the step of receiving the solid material to be heated from a reactor, preferably a carbonation reactor.

55. The method according to any one of claims 45 to 54, comprising the step of maintaining the heating temperature of the solid material at less than 550°C, preferably less than 500°C.

56. The method of claim 44, in combination with any one of claims 45 to 55, comprising the step of heating the heating gas using the heat recovered from the cooling of the solid material.

57. The method according to any one of claims 1 to 56, wherein the solid adsorbent is a solid adsorbent mixture.

58. The method according to any one of claims 1 to 57, wherein the solid adsorbent is a nanostructured adsorbent or comprises a nanostructured adsorbent.

59. A system for removing carbon dioxide from a gas containing carbon dioxide, The system includes a solid adsorbent, and is configured to, when in use, bring a gas containing carbon dioxide into contact with the fluidized solid adsorbent, thereby removing carbon dioxide from the gas and forming a gas from which carbon dioxide has been removed. system.

60. The system according to claim 59, wherein the system is configured to bring the gas containing carbon dioxide into contact with the solid adsorbent in the presence of water or one or more solvents, or a mixture of water and one or more solvents, when in use.

61. The system according to claim 60, wherein the system is configured to supply water to humidify the gas containing carbon dioxide to about 100% humidity when in use, or the system is configured to pass the gas containing carbon dioxide through water to create bubbles before bringing it into contact with the solid adsorbent when in use.

62. The system according to any one of claims 59 to 61, comprising one or more reactors configured to bring the gas containing carbon dioxide into contact with the solid adsorbent during use.

63. The system according to claim 62, wherein the one or more reactors are one or more fluidized bed reactors.

64. The system according to claim 63, wherein the one or more fluidized bed reactors have an aspect ratio of width to length in the range of 1:1 to 1:20, preferably 1:5, and more preferably 1:

3.

65. The system according to claim 63 or 64, comprising a plurality of parallel-arranged fluidized bed reactors configured to bring the gas containing carbon dioxide into contact with the solid adsorbent during use, wherein the gas containing carbon dioxide is in contact with the solid adsorbent in each of the plurality of parallel-arranged fluidized bed reactors.

66. The system according to claim 65, wherein the fluidized bed reactors are stacked on top of each other to form a vertical stack of fluidized bed reactors.

67. The system according to any one of claims 63 to 66, wherein the one or more fluidized bed reactors include a plurality of parallel-arranged fluidized bed subunits configured to bring the gas containing carbon dioxide into contact with the solid adsorbent during use, and the gas containing carbon dioxide is in contact with the solid adsorbent in each of the plurality of parallel-arranged fluidized bed subunits.

68. The system according to claim 67, wherein the fluidized bed subunits are stacked on top of each other to form a vertical stack of fluidized bed subunits.

69. The system according to any one of claims 63 to 68, wherein the system includes one or more gas distributors through which the gas is introduced to the one or more fluidized bed reactors when in use.

70. The system according to any one of claims 63 to 69, wherein the system includes one or more fans configured to introduce the gas into the one or more fluidized bed reactors when in use.

71. The system according to any one of claims 63 to 70, wherein the system includes a solid inlet and a solid outlet, and the system is configured to move the solid adsorbent from the solid inlet to the solid outlet along the length of the one or more fluidized bed reactors.

72. The system according to claim 71, as dependent on claim 70, wherein one or more fans are configured to move the solid adsorbent from the solid inlet to the solid outlet along the length of the one or more fluidized bed reactors when in use, and optionally, one or more fans are configured to gradually move the solid adsorbent from the solid inlet to the solid outlet along the length of the one or more fluidized bed reactors.

73. The system according to any one of claims 63 to 72, wherein the system comprises one or more separation units through which the gas from which the carbon dioxide has been removed is filtered during use.

74. The system according to claim 73, wherein the one or more separation units are or include a filter, a bag filter, a gas cyclone, or an electrostatic precipitator (ESP).

75. The system according to any one of claims 59 to 74, wherein the system is configured to bring the gas containing carbon dioxide into contact with the solid adsorbent at a temperature of 450°C to ambient temperature and a pressure of 1 to 1.5 bar during use.

76. The system according to any one of claims 59 to 75, wherein the system is configured to regenerate the solid adsorbent during use, thereby releasing carbon dioxide from the solid adsorbent and generating concentrated carbon dioxide gas.

77. The system according to claim 76, comprising a second reactor or kiln configured to regenerate the solid adsorbent during use.

78. The system according to claim 76 or 77, wherein the system is configured to regenerate the solid solvent by heating the solid adsorbent to a temperature of about 500 to 900°C during use.

79. The system according to any one of claims 76 to 78, wherein the system is configured to collect the concentrated carbon dioxide gas when in use.

80. The system according to any one of claims 76 to 79, wherein the system is configured to reactivate the solid adsorbent when in use.

81. The system according to claim 80, wherein the system is configured to reactivate the solid adsorbent in the presence of vapor at a temperature of ambient temperature to 900°C when in use.

82. A system according to any one of claims 59 to 81, wherein the gas containing carbon dioxide is air in the atmosphere.

83. A system according to any one of claims 59 to 82, wherein the gas containing carbon dioxide has a carbon dioxide concentration of less than 1000 ppm, more preferably less than 800 ppm, more preferably less than 600 ppm, and more preferably less than 500 ppm.

84. A system according to any one of claims 59 to 83, wherein the solid adsorbent comprises particles of the solid adsorbent, optionally comprising silica particles, and the average particle size of the solid adsorbent and silica particles is less than 2500 microns.

85. The average particle size of the solid adsorbent is 20 to 2000 microns, and its internal surface area is 1 to 200 m². ２ The system according to any one of claims 59 to 84, wherein the value is / g.

86. The system according to any one of claims 59 to 85, wherein the solid adsorbent is a mixed metal oxide or mixed metal hydroxide, and the metal oxide or metal hydroxide comprises one or more of Ca, Mg, Si, Al, Fe, W, Mn, Cu, Zn, Xo, Sr, Cd, Ba, and Ni.

87. The system according to claim 86, wherein the solid adsorbent comprises a mixed metal oxide or mixed metal hydroxide, the mixed metal oxide or mixed metal hydroxide comprises Ca and optionally further comprises one or more of Mg, Si, Al, Fe, W, Mn, Cu, Zn, Xo, Sr, Cd, Ba, and Ni.

88. The solid adsorbent comprises one or more salts of Li, Na, and / or K, hydroxides, nitrates, nitrites, and / or carbonates, and HBr, HCl, HNO ３ The system according to any one of claims 59 to 87, comprising, and any combination of HI.

89. The system according to any one of claims 59 to 88, wherein the solid adsorbent is Havelock limestone or a mixed metal oxide containing 85 wt% Ca and 15 wt% Mg.

90. The system according to any one of claims 59 to 89, wherein the system includes a cooling device configured to cool the solid material that has exited a reactor, preferably a calcination furnace reactor, during use, and the cooling device is configured to cool the solid material using a cooling gas during use.

91. The system according to claim 90, wherein the cooling device is configured to transport the solid material in a countercurrent with respect to the cooling gas.

92. The system according to claim 91, wherein the cooling device is configured to use gravity to transport the solid material in a countercurrent with the cooling gas.

93. The system according to claim 90, wherein the cooling device is configured to transport the solid material with respect to the cooling gas in a direct or alternating current.

94. The cooling device includes a plurality of cooling stages, according to any one of claims 90 to 93.

95. The system according to claim 94, wherein the plurality of cooling stages include a plurality of parallel-arranged cooling stages configured to cool each portion of the solid material using the cooling gas during use.

96. The system according to claim 94 or 95, wherein the plurality of cooling stages include a plurality of sequentially arranged cooling stages configured to sequentially cool the solid material using the cooling gas during use.

97. The system according to any one of claims 90 to 96, wherein the cooling device includes a hydration stage configured to hydrate the solid material when in use.

98. The system according to claim 96 or 97, wherein the hydration stage is configured to receive the solid material from one of the plurality of sequentially arranged cooling stages, and / or another cooling stage of the plurality of sequentially arranged cooling stages is configured to receive the solid material from the hydration stage when in use.

99. The system according to any one of claims 90 to 98, wherein the cooling device includes one or more fluidized bed coolers configured to cool the solid material using the cooling gas when in use, and the cooling gas is a fluidizing gas.

100. The system according to any one of claims 90 to 99, wherein the cooling gas is ambient air.

101. The system according to any one of claims 90 to 100, wherein the cooling device is configured to supply the cooled solid material to a material reactor, preferably a carbonation reactor, when in use.

102. The system according to any one of claims 90 to 101, comprising a heat exchanger configured to recover heat from the cooling of the solid material by the cooling device during use.

103. The system according to any one of claims 90 to 102, wherein the system includes a heating device configured to heat the solid material using a heating gas before the solid material enters a reactor, preferably a calcination furnace reactor, when in use.

104. The system according to claim 103, wherein the heating device is configured to transport the solid material in a countercurrent with respect to the heated gas.

105. The system according to claim 104, wherein the heating device is configured to use gravity to transport the solid material in a countercurrent with respect to the heated gas.

106. The system according to claim 103, wherein the heating device is configured to transport the solid material with respect to the heating gas in a direct or alternating current.

107. The heating device includes a plurality of heating stages, according to any one of claims 103 to 106.

108. The system according to claim 107, wherein the plurality of heating stages include a plurality of parallel-arranged heating stages configured to heat each portion of the solid material using the heating gas when in use.

109. The system according to claim 107 or 108, wherein the plurality of heating stages include a plurality of sequentially arranged heating stages configured to sequentially heat the solid material using the heating gas during use.

110. The system according to any one of claims 103 to 109, wherein the heating device includes one or more fluidized bed heaters configured to cool the solid material using the heating gas when in use, and the heating gas is a fluidizing gas.

111. The system according to any one of claims 103 to 110, wherein the heating device includes one or more cyclone flash heaters configured to heat the solid material using the heating gas when in use.

112. The system according to any one of claims 103 to 111, wherein the heating device is configured to receive the solid material to be heated from a reactor, preferably a carbonation reactor, when in use.

113. The system according to any one of claims 103 to 112, wherein the heating device is configured to maintain the heating temperature of the solid material at less than 550°C, preferably less than 500°C, during use.

114. The system according to claim 96, in combination with any one of claims 103 to 113, wherein the heating device is configured to heat the heating gas using heat recovered from the cooling of the solid material by the cooling device when in use.

115. The system according to any one of claims 59 to 114, wherein the solid adsorbent is a mixture of solid adsorbents.

116. The system according to any one of claims 59 to 115, wherein the solid adsorbent is a nanostructured adsorbent or comprises a nanostructured adsorbent.

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