Atomization rotational flow crystallization device and method for resource recovery of CO2 in combustion flue gas

Abstract

The invention discloses an atomization rotational flow crystallization device and method for resource recovery of CO2 in combustion flue gas, and relates to the technical field of recovery of CO2 in combustion flue gas, the atomization rotational flow crystallization device comprises a multi-point spray array gas inlet device, a spherical rotational flow device and a condensation crystallization device; according to the invention, the atomization rotational flow crystallization device is adopted to realize CO2 resource recovery of flue gas, the flue gas is firstly in full contact with atomization absorption liquid sprayed by the multi-point spraying array to form a flue gas absorption liquid mixture, the flue gas absorption liquid mixture is in a rotational flow state after entering the spherical rotational flow device, and gas-liquid phase separation is carried out, so that the CO2 resource recovery of the flue gas is realized. The liquid phase is condensed under the condensation action of the condensation crystallization device to obtain a solid phase product sodium bicarbonate and a liquid phase absorption liquid, and the liquid phase absorption liquid is subjected to temperature control adjustment and atomization again to provide an absorption liquid for the multi-point spray array; and the method can also be used for large-scale CO2 resource recovery scenes such as thermal power plants and the like, the process and equipment are stable and reliable, the operation is flexible, and the CO2 absorption conversion rate is high.

Description

Technical Field

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

[0002] At present, the commonly used methods for capturing CO2 in flue gas are nitrogen injection, temperature swing absorption, pressure swing absorption, adsorption membrane separation, etc. The above methods are generally aimed at objects such as coal-fired power plants that produce a large amount of CO2, and require a complex post-processing system. Other companies that use CO2 or (NH4)2CO3 as raw materials are difficult to apply to other companies with smaller flue gas volumes and more scattered distribution, such as glass factories and ceramic factories.

[0003] The absorption method uses alkaline solutions (such as MEA, DEA, MDEA, etc.) to absorb CO2 in flue gas to form bicarbonate or carbonate, and then releases CO2 by heating or decompression, thereby realizing CO2 recovery. The heating and decompression process requires a lot of energy. Alkaline solutions are corrosive to equipment, and corrosion-resistant materials need to be used, which increases costs.

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

[0005] Particulate matter and other components in the flue gas may contaminate or clog the membrane, reducing separation efficiency. The membrane material may age due to long-term use and need to be replaced regularly. Maintaining the working condition of the membrane requires a certain amount of energy consumption.

[0006] There is also a condensation method, which separates CO2 by lowering the temperature so that the CO2 in the flue gas reaches saturation and condenses. The cooling process requires a lot of energy. This method is suitable for flue gas with high CO2 concentration, and is less efficient for flue gas with low CO2 concentration.

[0007] These traditional processes have certain effects in CO2 recovery, but they all have certain disadvantages, such as high energy consumption, complex operation, high cost, corrosion and pollution of equipment, etc. Therefore, it is urgent to develop more efficient and economical CO2 recovery technology. Summary of the invention

[0008] In order to solve the technical problem of CO2 resource recovery in flue gas, the present invention provides an atomizing cyclone crystallization device and method for CO2 resource recovery in combustion flue gas. The following technical solutions are adopted:

[0009] An atomizing cyclone crystallization device for recycling CO2 in combustion flue gas, comprising a multi-point spray array air intake device, a spherical cyclone device and a condensation crystallization device;

[0010] The multi-point spray array air intake device comprises an air intake duct and a multi-point spray array, the smoke duct is connected to the air intake duct, and the multi-point spray array is installed on the inner wall of the air intake duct and is located at one end connected to the smoke duct;

[0011] The spherical cyclone device comprises a spherical shell, a plurality of cyclone guide plates and a condensation demister. A flue gas inlet is provided on one side of the spherical shell, a gas phase outlet is provided on the other side, and a liquid phase outlet is provided at the bottom. The plurality of cyclone guide plates are respectively installed on the inner wall of the spherical shell. The intervals between the plurality of cyclone guide plates are used to guide the incoming flue gas absorption liquid mixture into a cyclone state. The condensation demister is installed at the gas phase outlet and protrudes into the interior of 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 a solid phase product and a liquid absorption liquid. The liquid absorption liquid is then connected to the inlet of the multi-point spray array after temperature adjustment and atomization.

[0013] By adopting the above technical scheme, an atomizing cyclone crystallization device is used to realize the CO2 resource recovery of the flue gas after dust removal and desulfurization treatment. The flue gas first contacts with the atomized absorption liquid sprayed from the multi-point spray array to form a flue gas absorption liquid mixture. After entering the spherical cyclone device, the spherical cyclone device makes the flue gas absorption liquid mixture into a cyclone state under the guidance of some cyclone guide structures, and separates the gas and liquid phases in the cyclone state. The gas-liquid phase separation can be achieved by a condenser, etc. After the gas-liquid phase separation, the liquid phase is condensed by the condensation crystallization device to obtain a solid phase product and a liquid absorption liquid. The solid phase product refers to sodium bicarbonate. The liquid absorption liquid is again temperature-controlled and atomized to provide absorption liquid for the multi-point spray array.

[0014] There will still be residual CO2 in the gas phase after gas-liquid separation in the spherical cyclone device, and one or more absorption towers can be set up subsequently to recover the residual CO2.

[0015] It can realize the resource recovery of CO2 in the 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, flexible in operation, and have a high CO2 absorption conversion rate.

[0016] Optionally, the multi-point spray array includes multiple rows of spray assemblies, the spray assemblies include a bracket, multiple absorption liquid pipes and multiple groups of atomizing nozzles, the end of the bracket can be detachably mounted on the inner wall of the air inlet pipe, the multiple absorption liquid pipes can be detachably mounted on the bracket, the multiple groups of atomizing nozzles are respectively mounted at the nozzle mounting ports opened on the multiple absorption liquid pipes, and the multiple rows of spray assemblies are staggered with each other.

[0017] Optionally, the multiple groups of atomizing nozzles of the multiple-row spray assembly are all directed toward 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 assembly. In order to make the atomized absorption liquid contact with the flue gas more fully, it can be multiple rows of spray assemblies, for example three rows. The positions of the atomizing nozzles of the three rows of spray assemblies are staggered, and the absorption liquid is supplied to multiple absorption liquid pipelines respectively through the main pipeline. Finally, the atomized absorption liquid is sprayed toward the flue gas pipeline through multiple groups of atomizing nozzles in the opposite direction of the flue gas flow, thereby increasing the relative velocity of gas and liquid and increasing the CO2 absorption rate.

[0019] Optionally, the spherical cyclone device further comprises cyclone blades, and the cyclone blades are installed at the smoke inlet of the spherical shell.

[0020] By adopting the above technical solution, swirl blades are set at the flue gas inlet of the spherical shell, so that the flue gas is already in a swirl state when entering the spherical swirl device. The spherical shell is matched with multiple swirl guide plates, and swirl guide grooves are formed between adjacent swirl guide plates. The rotation radius of the flue gas absorption liquid mixture gradually increases in the early stage of the swirl, and the rotation radius gradually decreases after passing through the middle of the spherical shell. The swirl diameter gradually changes, and the pressure along the spherical surface is greater than that near the center line, so as to realize the inlet and outlet gas diversion in a small space, reduce the proportion of direct short-circuit gas outflow, and improve the mixing uniformity of the absorption liquid and the flue gas under the action of the internal swirl gas and the mainstream return gas, and improve the CO2 recovery rate. The condensation demister protrudes into the interior of the spherical shell, and the protruding part is generally set to reach one-quarter to one-third of the diameter of the spherical shell. The condensation array plate of the condensation demister adopts a V-shaped plate, and the V-shaped plates of different layers are staggered, which can efficiently condense the droplets, and the droplets aggregate and become larger and finally fall.

[0021] Optionally, the condensation crystallization device includes a condensation crystallization tank, a chiller, a cold 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 cold water coil is installed on the inner wall of the condensation crystallization tank, the circulating water inlet and outlet of the chiller are connected to both ends of the cold water coil, a condensation channel is formed in the cold water coil, and the inlet of the high-speed centrifugal separator is connected to the bottom opening of the condensation crystallization tank through a pipeline, so as to perform solid-liquid phase separation on the solid-liquid mixture falling from the condensation channel.

[0022] Optionally, a chiller controller is also included, and the chiller controller controls the water temperature injected into the cold water coil of the chiller to be 5°C-10°C.

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

[0024] Optionally, it also includes an absorption liquid recovery atomization device, which includes a stirring tank, an agitator, a heater and an atomizer. The inlet of the stirring tank is connected to the liquid phase outlet of the high-speed centrifuge through a pipeline, the agitator and the heater are respectively installed in the stirring tank, the inlet of the atomizer is connected to the outlet at the bottom of the stirring tank through a pipeline and a water pump, and the outlet of the atomizer is connected to the absorption liquid inlet of the multi-point spray array through a pipeline.

[0025] By adopting the above technical scheme, the concentration of sodium bicarbonate in the absorption liquid at the liquid phase outlet of the high-speed centrifuge becomes lower, the heater needs to heat the temperature of the stirring tank to 40°C-60°C, the stirrer continuously stirs to dissolve the sodium bicarbonate for the second time, and can also replenish the absorption liquid loss to the stirring tank. Finally, the prepared absorption liquid passes through the atomizer, which can be a two-phase flow atomizer or a single-phase flow atomizer. The atomized absorption liquid is input into the multi-point spray array again, thereby realizing the recycling of the recovered liquid.

[0026] The atomization cyclone crystallization method for recycling CO2 in combustion flue gas adopts an atomization cyclone crystallization device for recycling CO2 in combustion flue gas to carry out atomization cyclone crystallization to obtain a solid product, comprising the following steps:

[0027] Step 1, the flue gas to be recovered CO2 is introduced from the flue gas pipeline into the air intake pipeline, and the multi-point spray array sprays the atomized absorption liquid to form a gas-liquid mixture that enters the spherical shell;

[0028] Step 2: After the first swirl guide of the swirl blade, the gas-liquid mixture enters the guide groove between the multiple swirl guide plates to form a spherical swirl attached to the inner wall of the spherical shell. The rotation radius of the swirl gradually increases at the beginning, and gradually decreases after passing through the middle of the spherical shell. The condenser demister absorbs the droplets, and the droplets gradually become larger and fall off.

[0029] Step 4, the liquid phase after gas-liquid separation falls into the condensation crystallization tank, and the liquid phase temperature is set at 10°C-15°C under the cooling effect of 5°C-10°C provided by the cold water coil, and the solid-liquid mixture formed by condensation and crystallization enters the high-speed centrifuge. The high-speed centrifuge separates the solid-liquid phase of 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, and provides the absorption liquid for the atomizer after heating and stirring;

[0030] Step 5, the atomizer injects the atomized absorption liquid into a multi-point spray array.

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

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

[0033] The present invention can provide an atomizing cyclone crystallization device and method for recycling CO2 in combustion flue gas.

[0034] The atomized cyclone crystallization device is used to realize the CO2 resource recovery of the flue gas after dust removal and desulfurization treatment. The flue gas first contacts with the atomized absorption liquid sprayed from the multi-point spray array to form a flue gas absorption liquid mixture. After entering the spherical cyclone device, the flue gas absorption liquid mixture is made into a cyclone state, and the gas and liquid phases are separated in the cyclone state. After the gas and liquid phases are separated, the liquid phase is condensed by the condensation crystallization device to obtain the solid phase product sodium bicarbonate and the liquid absorption liquid. The liquid absorption liquid is again temperature-controlled and atomized to provide the absorption liquid for the multi-point spray array.

[0035] It can realize the resource recovery of CO2 in the 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, flexible in operation, and have a high CO2 absorption conversion rate. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0037] Figure 2 It is a schematic diagram of the connection of components of a mist ball cyclone device and a condensation crystallization device of an atomizing cyclone crystallization device for resource recovery of CO2 in combustion flue gas of the present invention.

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

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

[0040] Figure 5 It is a schematic diagram of the connection of components of an atomizing cyclonic crystallization device for resource recovery of CO2 in combustion flue gas of the present invention, which adds a concentration absorption tower and a depth absorption tower.

[0041] Explanation of the reference numerals: 11. air inlet duct; 12. multi-point spray array; 121. bracket; 122. absorption liquid duct; 123. atomizing nozzle; 131. spherical shell; 132. swirl guide plate; 133. condensation demister; 134. swirl blade; 141. condensation crystallization tank; 142. chiller; 143. cold water coil; 144. high-speed centrifugal separator; 2. concentration absorption tower; 3. deep absorption tower; 431. stirring tank; 432. stirrer; 44. atomizer; 100. flue gas duct. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0043] The embodiment of the present invention discloses an atomizing cyclone crystallization device and method for resource recovery of CO2 in combustion flue gas.

[0044] Reference Figure 1 - Figure 5 , Example 1, an atomizing cyclone crystallization device for recycling CO2 in combustion flue gas, comprising a multi-point spray array air intake device, a spherical cyclone 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 smoke 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 one end connected to the smoke pipe 100.

[0046] The spherical cyclone device includes a spherical shell 131, a plurality of cyclone guide plates 132 and a condensation demister 133. A flue gas inlet is provided on one side of the spherical shell 131, a gas phase outlet is provided on the other side, and a liquid phase outlet is provided at the bottom. The plurality of cyclone guide plates 132 are respectively installed on the inner wall of the spherical shell 131. The intervals between the plurality of cyclone guide plates 132 are used to guide the incoming flue gas absorption liquid mixture into a cyclone state. The condensation demister 133 is installed at the gas phase outlet and protrudes into the interior of the spherical shell 131.

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

[0048] An atomizing cyclone crystallization device is used to realize the CO2 resource recovery of the flue gas after dust removal and desulfurization treatment. The flue gas first contacts with the atomized absorption liquid sprayed from the multi-point spray array 12 to form a flue gas absorption liquid mixture. After entering the spherical cyclone device, the spherical cyclone device makes the flue gas absorption liquid mixture into a cyclone state under the guidance of some cyclone guide structures, and separates the gas and liquid phases in the cyclone state. The gas-liquid phase separation can be achieved by a condenser, etc. After the gas-liquid phase separation, the liquid phase is condensed by the condensation crystallization device to obtain a solid phase product and a liquid absorption liquid. The solid phase product refers to sodium bicarbonate. The liquid absorption liquid is again temperature-controlled and atomized to provide absorption liquid for the multi-point spray array 12;

[0049] There will still be residual CO2 in the gas phase after gas-liquid separation in the spherical cyclone device, and one or more absorption towers can be set up subsequently to recover the residual CO2.

[0050] It can realize the resource recovery of CO2 in the 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, flexible in operation, and have a high CO2 absorption conversion rate.

[0051] Embodiment 2, the multi-point spray array 12 includes multiple rows of spray components, the spray components include a bracket 121, multiple absorption liquid pipes 122 and multiple groups of atomizing nozzles 123, the end of the bracket 121 can be detachably mounted on the inner wall of the air inlet pipe 11, the multiple absorption liquid pipes 122 can be detachably mounted on the bracket 121, the multiple groups of atomizing nozzles 123 are respectively mounted on the nozzle mounting ports opened on the multiple absorption liquid pipes 122, and the multiple rows of spray components are staggered with each other.

[0052] In Example 3, the multiple groups of atomizing nozzles 123 of the multiple rows of spray assemblies are all directed toward the flue gas duct 100 .

[0053] The structure of the multi-point spray array 12 can be at least one spray assembly. In order to make the atomized absorption liquid contact with the flue gas more fully, it can be multiple rows of spray assemblies, for example three rows. The positions of the atomizing nozzles 123 of the three rows of spray assemblies are staggered, and the absorption liquid is supplied to multiple absorption liquid pipes 122 through the main pipeline. Finally, the atomized absorption liquid is sprayed toward the flue gas pipe 100 through multiple groups of atomizing nozzles 123 in the opposite direction of the flue gas flow, thereby increasing the relative velocity of gas and liquid and increasing the CO2 absorption rate.

[0054] In Example 4, the spherical cyclone device further includes a cyclone blade 134 , and the cyclone blade 134 is installed at the smoke inlet of the spherical shell 131 .

[0055] A swirl blade 134 is arranged at the flue gas inlet of the spherical shell 131, so that the flue gas is already in a swirl state when entering the spherical swirl device. The spherical shell 131 is matched with multiple swirl guide plates 132, and swirl guide grooves are formed between adjacent swirl guide plates 132. The rotation radius of the flue gas absorption liquid mixture gradually increases in the initial stage of the swirl, and gradually decreases after passing through the middle part of the spherical shell 131. The swirl diameter changes gradually, and the pressure along the spherical surface is greater than that near the center line, so that the inlet and outlet gas diversion in a small space is realized, and the proportion of direct short-circuit outflow of the gas is reduced. Under the action of the internal swirl gas and the mainstream return gas, the mixing uniformity of the absorption liquid and the flue gas is improved, and the CO2 recovery rate is improved. The condensation demister 133 protrudes into the interior of the spherical shell 131, and the protruding part is generally set to reach one quarter to one third of the diameter of the spherical shell 131. The condensation array plate of the condensation demister 133 adopts a V-shaped plate, and the V-shaped plates of different layers are staggered, which can efficiently condense droplets, and the droplets aggregate to become larger and finally fall.

[0056] Embodiment 5, the condensation crystallization device includes a condensation crystallization tank 141, a chiller 142, a cold 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 cold water coil 143 is installed on the inner wall of the condensation crystallization tank 141, the circulating water inlet and outlet of the chiller 142 are connected to the two ends of the cold water coil 143, a condensation channel is formed in the cold water coil 143, and the inlet of the high-speed centrifugal separator 144 is connected to the bottom opening of the condensation crystallization tank 141 through a pipeline, which is used for solid-liquid phase separation of the solid-liquid mixture falling from the condensation channel.

[0057] Embodiment 6 further comprises a chiller controller, which controls the water temperature of the chiller 142 injected into the cold water coil 143 to be 5°C-10°C.

[0058] The condensation crystallization device is based on a chiller 142 that provides 5°C-10°C cold water to the cold water coil 143, so that the temperature of the absorption liquid in the condensation crystallization tank 141 is 10-15 degrees, and the liquid phase is condensed to obtain a solid product of sodium bicarbonate. During the condensation process, some absorption liquid remains in a liquid state. The solid and liquid enter the high-speed centrifuge 144 together to achieve solid-liquid separation. The solid phase product is solid sodium bicarbonate, and the liquid absorption liquid flows into the subsequent absorption liquid circulation device for reuse, thereby efficiently realizing CO2 resource recovery, and the absorption liquid can be recycled repeatedly.

[0059] Example 7 also includes an absorption liquid recovery atomization device, which includes a stirring tank 431, an agitator 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 pipeline, the agitator 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 pipeline and a water pump, and the outlet of the atomizer 44 is connected to the absorption liquid inlet of the multi-point spray array 12 through a pipeline.

[0060] The sodium bicarbonate concentration in the absorption liquid at the liquid phase outlet of the high-speed centrifuge 144 becomes low, and the heater needs to heat the temperature of the stirring tank 431 to 40°C-60°C. The stirrer 432 continuously stirs to dissolve the sodium bicarbonate for the second time, and can also replenish the absorption liquid loss to the stirring tank 431. The final prepared absorption liquid passes through the atomizer 44, which can be a two-phase flow atomizer or a single-phase flow atomizer. The atomized absorption liquid is input into the multi-point spray array 12 again, thereby realizing the recycling of the recovered liquid.

[0061] Example 8, an atomized cyclone crystallization method for recycling CO2 in combustion flue gas, using an atomized cyclone crystallization device for recycling CO2 in combustion flue gas to perform atomized cyclone crystallization to obtain a solid product, comprising the following steps:

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

[0063] Step 2: After the first swirl guide of the swirl blade 134, the gas-liquid mixture enters the guide groove between the multiple swirl guide plates 132, forming a spherical swirl attached to the inner wall of the spherical shell 131. The rotation radius of the swirl gradually increases at the beginning, 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.

[0064] Step 4, the liquid phase after gas-liquid separation falls into the condensation crystallization tank 141, and under the cooling effect of 5°C-10°C cold water in the cold water coil 143, the liquid phase temperature is set at 10°C-15°C, and the solid-liquid mixture formed by condensation and crystallization enters the high-speed centrifuge 144. The high-speed centrifuge 144 separates the solid-liquid phase of the solid-liquid mixture falling from the condensation channel, and the solid phase is the CO2 resource recovery product. The liquid phase enters the spray absorption liquid adjustment device, and after heating and stirring, provides the absorption liquid for the atomizer 44;

[0065] Step 5: The atomizer 44 atomizes the absorption liquid and injects it into the multi-point spray array 12.

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

[0067] In Example 10, the gas phase outlet of the spherical cyclone device can also be connected to the concentration absorption tower 2, and 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, and 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 concentrating absorption tower 2, and is provided with a residual flue gas absorption inlet and a tail gas exhaust outlet. The residual flue gas absorption inlet is connected to the secondary flue gas outlet of the concentrating absorption tower 2, and the tail gas after multi-stage filler absorption is discharged from the tail gas exhaust outlet.

[0069] Specific application example: CO2 recycling of flue gas from an aluminum ash regeneration enterprise. The furnace type is a rotary kiln and the fuel is natural gas. The original flue gas purification process is: cyclone dust removal → SCR desulfurization → bag dust removal → wet desulfurization, and the operating flue gas volume is about 24,000 cubic meters per hour.

[0070] After being treated by the above-mentioned environmental protection facilities, the average concentration of CO2 in the flue gas is about 9%.

[0071] The atomizing cyclone crystallization method for recycling CO2 in combustion flue gas of the present invention is used to recycle carbon dioxide from flue gas, and the processing conditions are as follows:

[0072] Absorption crystallization stage: the absorption liquid spray volume is 20 cubic meters per hour, and the sodium carbonate concentration in the absorption liquid is about 10%;

[0073] The gas phase outlet of the spherical cyclone device is connected to a concentrated absorption tower 2: the absorption liquid circulation spraying volume is 80 cubic meters per 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 absorption liquid circulation spraying volume is 60 cubic meters per hour, the sodium carbonate concentration in the absorption liquid is about 18%, and the sodium hydroxide concentration is about 3%.

[0075] After absorption treatment, the removal rate of CO2 in flue gas is about 97%, and the average concentration of CO2 at the outlet is about 1.8g / cubic meter. The purity of the recovered sodium bicarbonate exceeds 95%, and the impurity part is mainly sodium carbonate, accounting for about 4%.

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

Claims

1. Atomizing cyclone crystallization device for recycling CO2 in combustion flue gas, characterized by: It includes a multi-point spray array air intake device, a spherical cyclone device and a condensation crystallization device; The multi-point spray array air intake device comprises an air intake pipe (11) and a multi-point spray array (12); the smoke 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 one end connected to the smoke pipe (100); The spherical cyclone device comprises a spherical shell (131), a plurality of cyclone guide plates (132) and a condensation demister (133); a smoke inlet is provided on one side of the spherical shell (131), a gas phase outlet is provided on the corresponding other side, and a liquid phase outlet is provided at the bottom; the plurality of cyclone guide plates (132) are respectively mounted on the inner wall of the spherical shell (131); the intervals between the plurality of cyclone guide plates (132) are used to guide the incoming smoke absorption liquid mixture into a cyclone state; the condensation demister (133) is mounted 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), and the liquid phase is condensed and crystallized, and then high-speed solid-liquid separation is performed to obtain a solid phase product and a liquid absorption liquid. The liquid absorption liquid is then temperature-controlled, adjusted, and atomized, and then connected to the inlet of the multi-point spray array (12).

2. The atomizing cyclone crystallization device for recycling CO2 in combustion flue gas according to claim 1 is characterized in that: The multi-point spray array (12) comprises a plurality of rows of spray assemblies, the spray assemblies comprising a bracket (121), a plurality of absorption liquid pipes (122) and a plurality of groups of atomizing nozzles (123), the end of the bracket (121) being detachably mounted on the inner wall of the air intake pipe (11), the plurality of absorption liquid pipes (122) being detachably mounted on the bracket (121), the plurality of groups of atomizing nozzles (123) being respectively mounted at nozzle mounting openings provided on the plurality of absorption liquid pipes (122), and the plurality of rows of spray assemblies being arranged in a staggered manner.

3. The atomizing cyclone crystallization device for recycling CO2 in combustion flue gas according to claim 2 is characterized in that: The multiple groups of atomizing nozzles (123) of the multiple rows of spray assemblies are all directed toward the smoke duct (100).

4. The atomizing cyclone crystallization device for recycling CO2 in combustion flue gas according to claim 3 is characterized in that: The spherical cyclone device further comprises a cyclone blade (134), wherein the cyclone blade (134) is installed at the smoke inlet of the spherical housing (131).

5. The atomizing cyclone crystallization device for recycling CO2 in combustion flue gas according to claim 4 is characterized in that: The condensation crystallization device comprises a condensation crystallization tank (141), a chiller (142), a cold 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 cold water coil (143) is installed around the inner wall of the condensation crystallization tank (141); the circulating water inlet and outlet of the chiller (142) are connected to both ends of the cold water coil (143); a condensation channel is formed in the cold 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 pipeline, so as to perform solid-liquid phase separation on the solid-liquid mixture falling from the condensation channel.

6. The atomizing cyclone crystallization device for recycling CO2 in combustion flue gas according to claim 5 is characterized in that: It also includes a chiller controller, which controls the water temperature of the chiller (142) injected into the cold water coil (143) to be 5°C-10°C.

7. The atomizing cyclone crystallization device for recycling CO2 in combustion flue gas according to claim 6 is characterized in that: The invention also includes an absorption liquid recovery atomization device, which includes a stirring tank (431), an agitator (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 centrifugal separator (144) through a pipeline. The agitator (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 pipeline and a water pump. The outlet of the atomizer (44) is connected to the absorption liquid inlet of the multi-point spray array (12) through a pipeline.

8. Atomization cyclone crystallization method for recycling CO2 in combustion flue gas, characterized by: The atomizing cyclone crystallization device for recycling CO2 in combustion flue gas as claimed in claim 7 is used to perform atomizing cyclone crystallization to obtain a solid product, comprising the following steps: Step 1, flue gas from which CO2 is to be recovered is introduced from the flue gas pipeline (100) into the air intake pipeline (11), and the multi-point spray array (12) sprays atomized absorption liquid to form a gas-liquid mixture which enters the spherical shell (131); Step 2, the gas-liquid mixture enters the guide groove between the plurality of swirl guide plates (132) after the first swirl guidance of the swirl blade (134), forming a spherical swirl attached to the inner wall of the spherical shell (131), the rotation radius of the swirl gradually increases at the initial stage, and gradually decreases after passing through the middle of the spherical shell (131), and the condensation demister (133) absorbs the droplets, and the droplets gradually become larger and fall off; Step 4, the liquid phase after gas-liquid separation falls into the condensation crystallization tank (141), and the liquid phase temperature is adjusted to 10°C-15°C under the cooling effect of 5°C-10°C provided by the cold water coil (143), and the solid-liquid mixture formed by condensation and crystallization enters the high-speed centrifuge (144). The high-speed centrifuge (144) separates the solid-liquid phase of the solid-liquid mixture falling from the condensation channel, and the solid phase is the CO2 resource recovery product. The liquid phase enters the spray absorption liquid adjustment device, and after heating and stirring, provides the absorption liquid for the atomizer (44); Step 5, the atomizer (44) atomizes the absorption liquid and injects it into the multi-point spray array (12).

9. The atomization cyclone crystallization method for recycling CO2 in combustion flue gas according to claim 8, characterized in that: In step 4, the heater of the spray absorption liquid adjustment device heats the liquid in the stirring tank (431) to 40°C-60°C.

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