Atomizing Cyclone Crystallization Device and Method for Resource Recovery of CO2 from Combustion Flue Gas

Abstract

This invention discloses an atomizing swirl crystallization device and method for CO2 resource recovery from combustion flue gas, relating to the field of CO2 recovery technology in combustion flue gas. The device includes a multi-point spray array inlet device, a spherical swirl device, and a condensation crystallization device. The invention uses an atomizing swirl crystallization device to achieve CO2 resource recovery from flue gas. The flue gas first comes into full contact with the atomized absorbent sprayed from the multi-point spray array to form a flue gas absorbent mixture. After entering the spherical swirl device, the flue gas absorbent mixture is swirled, and the gas and liquid phases are separated. The liquid phase is condensed by the condensation crystallization device to obtain the solid product sodium bicarbonate and the liquid absorbent. The liquid absorbent is then further temperature-controlled and atomized to provide absorbent for the multi-point spray array. This method achieves CO2 resource recovery from flue gas and can also be used in large-scale CO2 resource recovery scenarios such as thermal power plants. The process and equipment are stable, reliable, and flexible in operation, with a high CO2 absorption and conversion rate.

Description

Technical Field

[0001] This invention relates to the field of CO2 recovery technology from combustion flue gas, and in particular to an atomizing cyclone crystallization device and method for resource recovery of CO2 from combustion flue gas. Background Technology

[0002] Currently, CO2 capture in flue gas commonly uses methods such as nitrogen injection, temperature swing absorption, pressure swing absorption, and adsorption membrane separation. These methods are generally designed for coal-fired power plants and other entities with large CO2 production volumes, requiring complex post-treatment systems. They are also unsuitable for other enterprises that use CO2 or (NH4)2CO3 as raw materials, such as glass factories and ceramic factories, where flue gas volumes are smaller and more dispersed.

[0003] The absorption method uses alkaline solutions (such as MEA, DEA, MDEA, etc.) to absorb CO2 from flue gas, forming bicarbonates or carbonates. The CO2 is then released through heating or depressurization, thus achieving CO2 recovery. However, the heating and depressurization processes require significant energy. Furthermore, alkaline solutions are corrosive to equipment, necessitating the use of corrosion-resistant materials, which increases costs.

[0004] Membrane separation utilizes the selective permeability of a specific membrane to CO2 to separate CO2 from other gases.

[0005] Particulate matter and other components in flue gas can contaminate or clog membranes, reducing separation efficiency. Membrane materials may age with prolonged use and require periodic replacement. Maintaining membrane operation requires a certain amount of energy.

[0006] Another method is condensation, which involves lowering the temperature to saturate and condense the CO2 in the flue gas, thus separating the CO2. This cooling process requires a significant amount of energy. This method is suitable for flue gas with high CO2 concentrations, but less efficient for low-concentration CO2 flue gas.

[0007] While these traditional processes have shown some effectiveness in CO2 recovery, they all suffer from drawbacks such as high energy consumption, complex operation, high costs, and corrosion and pollution problems to equipment. Therefore, there is an urgent need to develop more efficient and economical CO2 recovery technologies. Summary of the Invention

[0008] To address the aforementioned technical problems related to the resource recovery of CO2 from flue gas, this invention provides an atomizing cyclone crystallization device and method for CO2 resource recovery from combustion flue gas. The technical solution adopted is as follows:

[0009] Atomizing swirl crystallization device for CO2 resource recovery from combustion flue gas includes a multi-point spray array air inlet device, a spherical swirl device, and a condensation crystallization device;

[0010] The multi-point spray array air intake device includes an air intake pipe and a multi-point spray array. The flue gas pipe is connected to the air intake pipe, and the multi-point spray array is installed on the inner wall of the air intake pipe and located at the end connected to the flue gas pipe.

[0011] The spherical swirl device includes a spherical shell, multiple swirl guide plates, and a condenser demister. The spherical shell has a flue gas inlet on one side, a gas phase outlet on the corresponding other side, and a liquid phase outlet at the bottom. The multiple swirl guide plates are respectively installed on the inner wall of the spherical shell. The interval between the multiple swirl guide plates is used to guide the incoming flue gas-absorbent mixture into a swirl state. The condenser demister is installed at the gas phase outlet and protrudes into the spherical shell.

[0012] The condensation and crystallization device is connected to the liquid phase outlet at the bottom of the spherical shell. After the liquid phase is condensed and crystallized, high-speed solid-liquid separation is performed to obtain solid phase products and liquid phase absorbent. The liquid phase absorbent is then connected to the inlet of the multi-point spray array after temperature control adjustment and atomization.

[0013] By adopting the above technical solution, an atomizing swirl crystallization device is used to realize the CO2 resource recovery of flue gas after dust removal and desulfurization treatment. The flue gas first comes into full contact with the atomized absorbent liquid sprayed by the multi-point spray array to form a flue gas absorbent liquid mixture. After entering the spherical swirl device, the spherical swirl device, under the guidance of some swirl guiding structures, makes the flue gas absorbent liquid mixture into a swirling state, and the gas-liquid phase is separated in the swirling state. The gas-liquid phase separation can be achieved by using a condenser, etc. After the gas-liquid phase separation, the liquid phase is condensed by the condensation crystallization device to obtain solid phase product and liquid phase absorbent liquid. The solid phase product is sodium bicarbonate. The liquid phase absorbent liquid is then subjected to temperature control adjustment and atomization to provide absorbent liquid for the multi-point spray array.

[0014] After gas-liquid separation, CO2 residues may remain in the gas phase of the spherical cyclone device. One or more absorption towers can be installed to recover the residual CO2.

[0015] It enables the resource recovery of CO2 from flue gas of enterprises with small flue gas volume and scattered distribution. It can also be used in large-scale CO2 resource recovery scenarios such as thermal power plants. The process and equipment are stable, reliable, and flexible in operation, with a high CO2 absorption and conversion rate.

[0016] Optionally, the multi-point spray array includes multiple rows of spray components. Each spray component includes a support, multiple absorbent pipes, and multiple sets of atomizing nozzles. The end of the support is detachably mounted on the inner wall of the air inlet pipe. The multiple absorbent pipes are detachably mounted on the support. The multiple sets of atomizing nozzles are respectively mounted at nozzle mounting ports opened on the multiple absorbent pipes. The multiple rows of spray components are arranged in a staggered manner.

[0017] Optionally, the multiple atomizing nozzles of the multi-row spray assembly are all oriented towards the flue gas duct.

[0018] By adopting the above technical solution, the structure of the multi-point spray array can be at least one spray component. In order to make the atomized absorbent liquid contact the flue gas more fully, it can be a multi-row spray component, such as three rows. The positions of the atomizing nozzles of the three-row spray components are staggered. The absorbent liquid is supplied to multiple absorbent liquid pipes through the main pipe. Finally, the atomized absorbent liquid is sprayed towards the flue gas pipe through multiple sets of atomizing nozzles. The atomized absorbent liquid is sprayed in the opposite direction to the flue gas flow, which increases the relative velocity of gas and liquid and increases the CO2 absorption rate.

[0019] Optionally, the spherical swirl device may further include swirl blades, which are installed at the flue gas inlet of the spherical shell.

[0020] By adopting the above technical solution, swirl blades are installed at the flue gas inlet of the spherical shell, so that the flue gas is already in a swirling state when it enters the spherical swirling device. The spherical shell is combined with multiple swirl guide plates, and swirl guide grooves are formed between adjacent swirl guide plates. The rotation radius of the flue gas-absorbent mixture gradually increases in the initial stage of swirling, and gradually decreases after passing through the middle of the spherical shell, resulting in a gradual change in swirl diameter. The pressure along the spherical surface is greater than near the center line, achieving gas separation within a small space and reducing the proportion of gas directly flowing out via short-circuit. The internal swirling gas, combined with the mainstream return gas, improves the mixing uniformity of the absorbent and flue gas, increasing the CO2 recovery rate. The condenser demister protrudes into the spherical shell, typically with the protruding portion reaching one-quarter to one-third of the spherical shell diameter. The condenser demister's condensation array plates use V-shaped plates, with different layers of V-shaped plates staggered, which can efficiently condense droplets, causing them to aggregate, grow larger, and finally fall.

[0021] Optionally, the condensation crystallization device includes a condensation crystallization tank, a chiller, a chilled water coil, and a high-speed centrifugal separator. The top opening of the condensation crystallization tank is connected to the liquid phase outlet at the bottom of the spherical shell. The chilled water coil is installed around the inner wall of the condensation crystallization tank. The circulating inlet and outlet of the chiller are connected to both ends of the chilled water coil, forming a condensation channel in the chilled water coil. The inlet of the high-speed centrifugal separator is connected to the bottom opening of the condensation crystallization tank through a pipe, which is used to separate the solid-liquid mixture falling into the condensation channel.

[0022] Optionally, a chiller controller is also included, which controls the water temperature injected into the chilled water coil of the chiller to be 5℃-10℃.

[0023] By adopting the above technical solution, the condensation crystallization device provides 5℃-10℃ cold water to the condensation coil based on a chiller, so that the temperature of the absorbent in the condensation crystallization tank is 10-15 degrees, realizing the condensation of the liquid phase to obtain sodium bicarbonate solid product. During the condensation process, some absorbent remains in a liquid state. The solid and liquid are sent together to a high-speed centrifuge to achieve solid-liquid separation. The solid product is solid sodium bicarbonate, and the liquid absorbent flows into the subsequent absorbent recycling device for reuse, which efficiently realizes the resource recovery of CO2, and the absorbent can be repeatedly recycled.

[0024] Optionally, it also includes an absorbent recovery atomizing device, which includes a stirring tank, a stirrer, a heater, and an atomizer. The inlet of the stirring tank is connected to the liquid phase outlet of a high-speed centrifuge via a pipe. The stirrer and the heater are respectively installed inside the stirring tank. The inlet of the atomizer is connected to the outlet at the bottom of the stirring tank via a pipe and a water pump. The outlet of the atomizer is connected to the absorbent inlet of the multi-point spray array via a pipe.

[0025] By adopting the above technical solution, the concentration of sodium bicarbonate in the absorbent at the liquid outlet of the high-speed centrifugal separator becomes lower. The heater needs to heat the temperature of the stirred tank to 40℃-60℃, and the stirrer continuously stirs to dissolve the sodium bicarbonate a second time. It can also replenish the absorbent lost in the stirred tank. Finally, the prepared absorbent passes through an atomizer, which can be a two-phase flow atomizer or a single-phase flow atomizer. The atomized absorbent is then fed back into the multi-point spray array, realizing the recycling of the recovered liquid.

[0026] A method for CO2 resource recovery from combustion flue gas using atomized cyclone crystallization device to obtain a solid product through atomized cyclone crystallization, comprising the following steps:

[0027] Step 1: The flue gas to be recovered for CO2 is introduced into the intake pipe from the flue gas pipe, and the multi-point spray array sprays out atomized absorbent liquid to form a gas-liquid mixture that enters the spherical shell.

[0028] Step 2: After the gas-liquid mixture is first guided by the swirl blades, it enters the guide groove between multiple swirl guide plates, forming a spherical swirling flow that adheres to the inner wall of the spherical shell. In the early stage of the swirling flow, the radius of rotation gradually increases, and after passing through the middle of the spherical shell, the radius of rotation gradually decreases. The condenser absorbs the droplets, and the droplets gradually become larger and fall off.

[0029] Step 4: After gas-liquid separation, the liquid phase falls into the condensation crystallization tank. Under the cooling effect of 5℃-10℃ provided by the cold water coil, the temperature of the liquid phase is kept at 10℃-15℃. The solid-liquid mixture is condensed and crystallized and enters the high-speed centrifugal separator. The high-speed centrifugal separator separates the solid-liquid mixture falling from the condensation channel. The solid phase is the CO2 resource recovery product, and the liquid phase enters the spray absorption liquid adjustment device. After being heated and stirred, it provides the absorption liquid for the atomizer.

[0030] Step 5: The atomizer injects the atomized absorbent liquid into a multi-point spray array.

[0031] Optionally, in step 4, the heater of the spray absorbent adjustment device heats the liquid in the mixing tank to 40°C-60°C.

[0032] In summary, the present invention has at least one of the following beneficial technical effects:

[0033] This invention provides an atomizing cyclone crystallization device and method for the resource recovery of CO2 from combustion flue gas.

[0034] Atomizing swirl crystallization device is used to recover CO2 from flue gas that has undergone dust removal and desulfurization. The flue gas first comes into full contact with the atomized absorbent sprayed by the multi-point spray array to form a flue gas absorbent mixture. After entering the spherical swirl device, the flue gas absorbent mixture is made into a swirling state, and the gas and liquid phases are separated in the swirling state. After the gas and liquid phases are separated, the liquid phase is condensed by the condensation crystallization device to obtain the solid product sodium bicarbonate and the liquid absorbent. The liquid absorbent is then temperature controlled and atomized again to provide absorbent for the multi-point spray array.

[0035] It enables the resource recovery of CO2 from flue gas of enterprises with small flue gas volume and scattered distribution. It can also be used in large-scale CO2 resource recovery scenarios such as thermal power plants. The process and equipment are stable, reliable, and flexible in operation, with a high CO2 absorption and conversion rate. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the component connection principle of the atomizing cyclone crystallization device for resource recovery of CO2 from combustion flue gas according to the present invention;

[0037] Figure 2 This is a schematic diagram showing the connection between the fog ball-shaped swirl device and the condensation crystallization device of the atomizing swirl crystallization device for CO2 resource recovery from combustion flue gas according to the present invention.

[0038] Figure 3 This is a schematic diagram of the flue gas inlet structure of the spherical shell of the atomizing cyclone crystallization device for CO2 resource recovery from combustion flue gas according to the present invention;

[0039] Figure 4This is a schematic diagram of the multi-point spray array structure of the atomizing cyclone crystallization device for resource recovery of CO2 from combustion flue gas according to the present invention;

[0040] Figure 5 This is a schematic diagram showing the component connections of the atomized cyclone crystallizer for CO2 resource recovery from combustion flue gas according to the present invention, which includes a concentration absorption tower and a deep absorption tower.

[0041] Explanation of reference numerals in the attached drawings: 11. Inlet pipe; 12. Multi-point spray array; 121. Support; 122. Absorbent liquid pipe; 123. Atomizing nozzle; 131. Spherical shell; 132. Swirl guide plate; 133. Condensation demister; 134. Swirl blade; 141. Condensation crystallizer; 142. Chiller; 143. Chiller coil; 144. High-speed centrifuge; 2. Concentration absorption tower; 3. Deep absorption tower; 431. Mixing tank; 432. Agitator; 44. Atomizer; 100. Flue gas pipe. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the accompanying drawings.

[0043] This invention discloses an atomizing cyclone crystallization device and method for the resource recovery of CO2 from combustion flue gas.

[0044] Reference Figure 1 - Figure 5 Example 1: Atomizing swirl crystallization device for CO2 resource recovery from combustion flue gas, comprising a multi-point spray array air intake device, a spherical swirl device, and a condensation crystallization device;

[0045] The multi-point spray array air intake device includes an air intake pipe 11 and a multi-point spray array 12. The flue gas pipe 100 is connected to the air intake pipe 11, and the multi-point spray array 12 is installed on the inner wall of the air intake pipe 11 and located at the end connected to the flue gas pipe 100.

[0046] The spherical swirl device includes a spherical shell 131, multiple swirl guide plates 132, and a condenser demister 133. The spherical shell 131 has a flue gas inlet on one side, a gas phase outlet on the corresponding other side, and a liquid phase outlet at the bottom. The multiple swirl guide plates 132 are respectively installed on the inner wall of the spherical shell 131. The interval between the multiple swirl guide plates 132 is used to guide the incoming flue gas-absorbent mixture into a swirl state. The condenser demister 133 is installed at the gas phase outlet and protrudes into the interior of the spherical shell 131.

[0047] The condensation and crystallization device is connected to the liquid phase outlet at the bottom of the spherical shell 131. After the liquid phase is condensed and crystallized, high-speed solid-liquid separation is performed to obtain solid phase products and liquid phase absorbent. The liquid phase absorbent is then connected to the inlet of the multi-point spray array 12 after temperature control adjustment and atomization.

[0048] A swirling crystallizer is used to recover CO2 from flue gas that has undergone dust removal and desulfurization. The flue gas first comes into full contact with the atomized absorbent liquid sprayed from the multi-point spray array 12 to form a flue gas absorbent liquid mixture. After entering the spherical swirling device, the mixture is guided by certain swirling guide structures to form a swirling state, where gas and liquid phases separate. This separation can be achieved using a condenser. After separation, the liquid phase is condensed by the condensation crystallizer to obtain a solid product and a liquid absorbent liquid. The solid product is sodium bicarbonate. The liquid absorbent liquid is then further temperature-controlled and atomized to provide absorbent liquid for the multi-point spray array 12.

[0049] After gas-liquid separation, CO2 residues may remain in the gas phase of the spherical cyclone device. One or more absorption towers can be installed to recover the residual CO2.

[0050] It enables the resource recovery of CO2 from flue gas of enterprises with small flue gas volume and scattered distribution. It can also be used in large-scale CO2 resource recovery scenarios such as thermal power plants. The process and equipment are stable, reliable, and flexible in operation, with a high CO2 absorption and conversion rate.

[0051] Example 2: The multi-point spray array 12 includes multiple rows of spray components. Each spray component includes a bracket 121, multiple absorbent pipes 122, and multiple sets of atomizing nozzles 123. The end of the bracket 121 is detachably mounted on the inner wall of the air inlet pipe 11. The multiple absorbent pipes 122 are detachably mounted on the bracket 121. The multiple sets of atomizing nozzles 123 are respectively mounted at the nozzle mounting ports opened on the multiple absorbent pipes 122. The multiple rows of spray components are staggered with each other.

[0052] In Example 3, the multiple atomizing nozzles 123 of the multi-row spray assembly are all oriented towards the flue gas duct 100.

[0053] The structure of the multi-point spray array 12 can be at least one spray component. In order to make the atomized absorbent liquid contact the flue gas more fully, it can be a multi-row spray component, such as three rows. The positions of the atomizing nozzles 123 of the three-row spray components are staggered. The absorbent liquid is supplied to multiple absorbent liquid pipes 122 through the main pipe. Finally, the atomized absorbent liquid is sprayed towards the flue gas pipe 100 through multiple sets of atomizing nozzles 123. The atomized absorbent liquid is sprayed in the opposite direction to the flue gas flow, which increases the relative velocity of gas and liquid and increases the CO2 absorption rate.

[0054] Example 4: The spherical swirl device also includes swirl blades 134, which are installed at the flue gas inlet of the spherical shell 131.

[0055] Swirl blades 134 are installed at the flue gas inlet of the spherical shell 131, so that the flue gas is already in a swirling state when it enters the spherical swirling device. The spherical shell 131 is combined with multiple swirling guide plates 132, and swirling guide grooves are formed between adjacent swirling guide plates 132. The rotation radius of the flue gas absorbent mixture gradually increases in the early stage of swirling, and gradually decreases after passing through the middle of the spherical shell 131. The swirling diameter gradually changes, and the pressure along the spherical surface is greater than that near the center line, realizing the separation of inlet and outlet gas in a small space, reducing the proportion of gas directly short-circuiting out. Under the action of the internal swirling gas and the mainstream return gas, the mixing uniformity of absorbent and flue gas is improved, and the CO2 recovery rate is improved. The condenser 133 protrudes into the spherical shell 131. Generally, the protruding part is set to reach one-quarter to one-third of the diameter of the spherical shell 131. The condenser array plate of the condenser 133 adopts V-shaped plates. Different layers of V-shaped plates are staggered and installed, which can efficiently condense droplets, and the droplets aggregate, grow larger and finally fall.

[0056] Example 5: The condensation crystallization device includes a condensation crystallization tank 141, a chiller 142, a chilled water coil 143, and a high-speed centrifugal separator 144. The top opening of the condensation crystallization tank 141 is connected to the liquid phase outlet at the bottom of the spherical shell 131. The chilled water coil 143 is installed around the inner wall of the condensation crystallization tank 141. The circulation inlet and outlet of the chiller 142 are connected to both ends of the chilled water coil 143, forming a condensation channel in the chilled water coil 143. The inlet of the high-speed centrifugal separator 144 is connected to the bottom opening of the condensation crystallization tank 141 through a pipe, which is used to separate the solid-liquid mixture falling into the condensation channel.

[0057] Example 6 also includes a chiller controller, which controls the water temperature injected into the chilled water coil 143 by the chiller 142 to be 5℃-10℃.

[0058] The condensation crystallization device uses a chiller 142 to supply chilled water at 5℃-10℃ to the chilled water coil 143, so that the temperature of the absorbent liquid in the condensation crystallization tank 141 is 10-15℃. This allows the liquid phase to be condensed to obtain solid sodium bicarbonate. During the condensation process, some absorbent liquid remains in a liquid state. The solid and liquid phases are then fed into a high-speed centrifuge 144 for solid-liquid separation. The solid phase product is solid sodium bicarbonate, and the liquid absorbent liquid flows into a subsequent absorbent liquid recycling device for reuse. This efficiently achieves CO2 resource recovery, and the absorbent liquid can be repeatedly recycled.

[0059] Example 7 also includes an absorbent recovery atomizing device, which includes a stirring tank 431, a stirrer 432, a heater, and an atomizer 44. The inlet of the stirring tank 431 is connected to the liquid phase outlet of the high-speed centrifuge 144 through a pipe. The stirrer 432 and the heater are respectively installed inside the stirring tank 431. The inlet of the atomizer 44 is connected to the outlet at the bottom of the stirring tank 431 through a pipe and a water pump. The outlet of the atomizer 44 is connected to the absorbent inlet of the multi-point spray array 12 through a pipe.

[0060] The concentration of sodium bicarbonate in the absorbent at the liquid outlet of the high-speed centrifuge 144 decreases. The heater needs to heat the temperature of the stirring tank 431 to 40℃-60℃. The stirrer 432 continuously stirs the solution to dissolve the sodium bicarbonate a second time. It can also replenish the absorbent lost in the stirring tank 431. The final prepared absorbent passes through the atomizer 44, which can be a two-phase flow atomizer or a single-phase flow atomizer. The atomized absorbent is then fed back into the multi-point spray array 12, realizing the recycling of the recovered liquid.

[0061] Example 8, an atomized cyclone crystallization method for CO2 resource recovery from combustion flue gas, using an atomized cyclone crystallization device for CO2 resource recovery from combustion flue gas to obtain a solid product, including the following steps:

[0062] Step 1: The flue gas to be recovered for CO2 is introduced into the intake pipe 11 from the flue gas pipe 100. The multi-point spray array 12 sprays out atomized absorption liquid to form a gas-liquid mixture that enters the spherical shell 131.

[0063] Step 2: After the gas-liquid mixture is first guided by the swirl vane 134, it enters the guide groove between multiple swirl guide plates 132, forming a spherical swirling flow attached to the inner wall of the spherical shell 131. In the early stage of the swirling flow, the radius of rotation gradually increases, and after passing through the middle of the spherical shell 131, the radius of rotation gradually decreases. The condenser demister 133 absorbs the droplets, and the droplets gradually become larger and fall off.

[0064] Step 4: After gas-liquid separation, the liquid phase falls into the condensation crystallization tank 141. Under the cooling effect of 5℃-10℃ cold water in the cold water coil 143, the temperature of the liquid phase is kept between 10℃-15℃. The solid-liquid mixture is condensed and crystallized and enters the high-speed centrifugal separator 144. The high-speed centrifugal separator 144 separates the solid-liquid mixture falling from the condensation channel. The solid phase is the CO2 resource recovery product, and the liquid phase enters the spray absorption liquid adjustment device. After heating and stirring, it provides absorption liquid for the atomizer 44.

[0065] Step 5: The atomizer 44 injects the atomized absorbent liquid into the multi-point spray array 12.

[0066] In Example 9, in step 4, the heater of the spray absorbent adjustment device heats the liquid in the stirring tank 431 to 40°C-60°C.

[0067] Example 10: A concentration absorption tower 2 can also be connected to the gas phase outlet of the spherical cyclone device. The concentration absorption tower 2 is provided with a secondary flue gas absorption inlet and a secondary flue gas outlet. The gas phase outlet of the spherical cyclone device is connected to the secondary flue gas absorption inlet. The flue gas after multi-stage spray absorption is discharged through the secondary flue gas outlet.

[0068] A deep absorption tower 3 is connected after the concentration absorption tower 2. It is equipped with a residual flue gas absorption inlet and a tail gas discharge outlet. The residual flue gas absorption inlet is connected to the secondary flue gas outlet of the concentration absorption tower 2. The tail gas after being absorbed by the multi-stage packing is discharged from the tail gas discharge outlet.

[0069] Specific application example: CO2 resource recovery from flue gas of an aluminum ash recycling company. The furnace type is a rotary kiln, and the fuel is natural gas. The original flue gas purification process was: cyclone dust collector → SCR denitrification → bag filter dust collector → wet desulfurization, with a flue gas volume of approximately 24,000 cubic meters per hour under operating conditions.

[0070] After treatment by the aforementioned environmental protection facilities, the average concentration of CO2 in the flue gas was approximately 9%.

[0071] The atomized swirl crystallization method for CO2 resource recovery from combustion flue gas according to the present invention is used for CO2 resource recovery from flue gas. The treatment conditions are as follows:

[0072] Absorption and crystallization section: The spray volume of the absorbent is 20 cubic meters per hour, and the sodium carbonate concentration in the absorbent is approximately 10%.

[0073] A concentration absorption tower 2 is connected to the gas phase outlet of the spherical cyclone device: the absorption liquid circulation spray rate is 80 cubic meters / hour, and the sodium carbonate concentration in the absorption liquid is about 15%.

[0074] A deep absorption tower is connected after the concentration absorption tower 2: the circulation spray rate of the absorbent is 60 cubic meters / hour, the sodium carbonate concentration in the absorbent is about 18%, and the sodium hydroxide concentration is about 3%.

[0075] After absorption treatment, the CO2 removal rate in the flue gas is approximately 97%, and the average CO2 concentration at the outlet is approximately 1.8 g / m³. The recovered sodium bicarbonate has a purity exceeding 95%, with the main impurity being sodium carbonate, accounting for approximately 4%.

[0076] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An atomized cyclone crystallization method for resource recovery of CO2 from combustion flue gas, characterized in that: A solid product is obtained by using an atomizing cyclone crystallization device for CO2 resource recovery from combustion flue gas, including the following steps: Step 1: The flue gas to be recovered for CO2 is introduced into the inlet pipe (11) from the flue gas pipe (100), and the multi-point spray array (12) sprays out the atomized absorption liquid to form a gas-liquid mixture that enters the spherical shell (131). Step 2: After the gas-liquid mixture is first guided by the swirl vane (134), it enters the guide groove between multiple swirl guide plates (132) to form a spherical swirl attached to the inner wall of the spherical shell (131). The rotation radius gradually increases in the early stage of the swirl, and gradually decreases after passing through the middle of the spherical shell (131). The condenser demister (133) absorbs the droplets, and the droplets gradually become larger and fall off. Step 4: After gas-liquid separation, the liquid phase falls into the condensation crystallization tank (141). Under the cooling effect of 5℃-10℃ provided by the cold water coil (143), the liquid phase temperature is kept at 10℃-15℃. The solid-liquid mixture is condensed and crystallized and enters the high-speed centrifugal separator (144). The high-speed centrifugal separator (144) separates the solid-liquid mixture falling from the condensation channel. The solid phase is the CO2 resource recovery product, and the liquid phase enters the spray absorption liquid adjustment device. After heating and stirring, it provides absorption liquid for the atomizer (44). Step 5, the atomizer (44) injects the atomized absorbent into the multi-point spray array (12). The atomizing swirl crystallization device for CO2 resource recovery from combustion flue gas includes a multi-point spray array air inlet device, a spherical swirl device, and a condensation crystallization device. The multi-point spray array air intake device includes an air intake pipe (11) and a multi-point spray array (12). The flue gas pipe (100) is connected to the air intake pipe (11). The multi-point spray array (12) is installed on the inner wall of the air intake pipe (11) and is located at the end connected to the flue gas pipe (100). The spherical swirl device includes a spherical shell (131), multiple swirl guide plates (132), and a condenser demister (133). The spherical shell (131) has a flue gas inlet on one side, a gas phase outlet on the corresponding other side, and a liquid phase outlet at the bottom. The multiple swirl guide plates (132) are respectively installed on the inner wall of the spherical shell (131). The interval between the multiple swirl guide plates (132) is used to guide the incoming flue gas-absorbent mixture into a swirl state. The condenser demister (133) is installed at the gas phase outlet and protrudes into the interior of the spherical shell (131). The condensation and crystallization device is connected to the liquid phase outlet at the bottom of the spherical shell (131). After the liquid phase is condensed and crystallized, high-speed solid-liquid separation is performed to obtain solid phase products and liquid phase absorbent. The liquid phase absorbent is then connected to the inlet of the multi-point spray array (12) after temperature control adjustment and atomization.

2. The atomized cyclone crystallization method for resource recovery of CO2 from combustion flue gas according to claim 1, characterized in that: The multi-point spray array (12) includes multiple rows of spray components. Each spray component includes a bracket (121), multiple absorbent pipes (122), and multiple sets of atomizing nozzles (123). The end of the bracket (121) is detachably mounted on the inner wall of the air inlet pipe (11). The multiple absorbent pipes (122) are detachably mounted on the bracket (121). The multiple sets of atomizing nozzles (123) are respectively mounted at the nozzle mounting ports opened on the multiple absorbent pipes (122). The multiple rows of spray components are staggered.

3. The atomized cyclone crystallization method for resource recovery of CO2 from combustion flue gas according to claim 2, characterized in that: The multiple atomizing nozzles (123) of the multi-row spray assembly are all oriented toward the flue gas duct (100).

4. The atomized cyclone crystallization method for CO2 resource recovery from combustion flue gas according to claim 3, characterized in that: The spherical swirl device also includes swirl blades (134) installed at the flue gas inlet of the spherical shell (131).

5. The atomized cyclone crystallization method for resource recovery of CO2 from combustion flue gas according to claim 4, characterized in that: The condensation crystallization device includes a condensation crystallization tank (141), a chiller (142), a chilled water coil (143), and a high-speed centrifuge (144). The top opening of the condensation crystallization tank (141) is connected to the liquid phase outlet at the bottom of the spherical shell (131). The chilled water coil (143) is installed around the inner wall of the condensation crystallization tank (141). The circulation inlet and outlet of the chiller (142) are connected to both ends of the chilled water coil (143). A condensation channel is formed in the chilled water coil (143). The inlet of the high-speed centrifuge (144) is connected to the bottom opening of the condensation crystallization tank (141) through a pipe, which is used to separate the solid-liquid mixture falling into the condensation channel.

6. The atomized cyclone crystallization method for CO2 resource recovery from combustion flue gas according to claim 5, characterized in that: It also includes a chiller controller, which controls the water temperature injected into the chilled water coil (143) by the chiller (142) to be 5℃-10℃.

7. The atomized cyclone crystallization method for CO2 resource recovery from combustion flue gas according to claim 6, characterized in that: It also includes an absorbent recovery atomizing device, which includes a stirring tank (431), a stirrer (432), a heater and an atomizer (44). The inlet of the stirring tank (431) is connected to the liquid phase outlet of the high-speed centrifuge (144) through a pipe. The stirrer (432) and the heater are respectively installed in the stirring tank (431). The inlet of the atomizer (44) is connected to the outlet at the bottom of the stirring tank (431) through a pipe and a water pump. The outlet of the atomizer (44) is connected to the absorbent inlet of the multi-point spray array (12) through a pipe.

8. The atomized cyclone crystallization method for resource recovery of CO2 from combustion flue gas according to claim 7, characterized in that: In step 4, the heater of the spray absorbent adjustment device heats the liquid in the mixing tank (431) to 40°C-60°C.

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