JP4354788B2 - Gas processing equipment - Google Patents

Description

  The present invention relates to carbon dioxide generated from combustion devices such as boilers, gas turbines, gas engines and combustion furnaces, microbial treatment devices such as methane fermentation, and carbon-containing material reforming treatment devices such as fuel cells and hydrogen production. The present invention relates to a gas processing apparatus that separates and recovers carbon dioxide from a contained gas to be processed and outputs it.

  In recent years, the greenhouse effect due to carbon dioxide has been pointed out as one of the causes of global warming, and countermeasures are urgently needed internationally to protect the global environment.

  This carbon dioxide is emitted when each country consumes fossil fuels (carbon-containing fuel) to produce energy in order to cover the enormous use of energy by mankind. In order to suppress the decrease in fossilization, carbon dioxide emission regulations during fossil fuel combustion tend to be further strengthened in the future.

  Therefore, in each country, in addition to research on alternative energy other than fossil fuels, a method for recovering carbon dioxide in exhaust gas discharged during fossil fuel combustion, targeting energy generation facilities such as power plants that use large amounts of fossil fuels, and A method for storing the recovered carbon dioxide without releasing it to the atmosphere has been vigorously studied.

  As an example of the carbon dioxide recovery method, Non-Patent Document 1 proposes a carbon dioxide recovery method by an amine method using an ethanolamine derivative.

Further, when the carbon dioxide-containing gas is brought into contact with the metal oxide to react the carbon dioxide contained in the gas with the metal oxide to form a metal carbonate, and when the fuel is burned with pure oxygen, the metal carbonate is burned. Patent Document 1 proposes a technique for separating carbon dioxide by thermal decomposition with the combustion heat obtained in the above.
"Energy and Resources", published by Japan Society of Energy and Resources, vol.23, No.5,307-311, (2002) JP-A-8-24571

However, the method for separating and recovering carbon dioxide from combustion exhaust gas using the conventional amine method described above uses an ethanolamine aqueous solution as a carbon dioxide separation material, and the amount of carbon dioxide absorbed per unit volume of the ethanolamine aqueous solution is large. Therefore, it is necessary to circulate a large amount of aqueous amine solution, which consumes a large amount of pump power.
Furthermore, in the carbon dioxide separation and recovery method using the conventional amine method, a large amount of heat energy required for heating the monoethanolamine aqueous solution that has absorbed carbon dioxide is not used as low-temperature waste heat elsewhere. Since it is discarded, the thermal efficiency and energy efficiency of the entire carbon dioxide separation and recovery system are reduced.
Moreover, in order to make the metal oxide absorb carbon dioxide contained in the gas, the metal oxide and the gas are maintained at a high temperature, and in order to release carbon dioxide from the metal carbonate, the metal carbonate is heated. This reduces the thermal and energy efficiency of the overall carbon dioxide separator.
The present invention has been made in view of such circumstances, and by reusing the supplied thermal energy without releasing it to the outside, the energy required for carbon dioxide recovery is reduced. An object of the present invention is to provide a gas processing apparatus capable of improving the energy efficiency of the entire energy plant in which is incorporated.

In order to solve the above-described problems, the present invention provides a gas processing apparatus that separates and recovers a part of carbon dioxide contained in an input processing target gas and outputs the processing target for preheating the input processing target gas. A gas preheater and a carbon dioxide absorbent containing at least a lithium composite oxide that reversibly absorbs and releases carbon dioxide are housed, and carbon dioxide contained in the gas to be treated preheated by the gas preheater to be treated is A carbon dioxide absorption reactor to be absorbed by the carbon dioxide absorbent,
A process gas heat recovery unit that recovers heat of the process gas after the carbon dioxide discharged from the carbon dioxide absorption reactor is absorbed and supplies the process gas heat to the target gas preheater, and a state in which the carbon dioxide is absorbed A carbon dioxide release reactor that stores the absorbed carbon dioxide absorber and heats the absorbed carbon dioxide absorber with the supplied heated gas to release carbon dioxide, and heating that is supplied to the carbon dioxide release reactor A heated gas generator that generates gas, a released gas heat recovery device that recovers the heat of the released carbon dioxide output from the carbon dioxide release reactor, and a heat that is recovered from the heated gas medium by the released gas heat recovery device And a heated gas preheater for preheating . Further, the heated gas generator heats the heated gas medium preheated by the heated gas preheater with the combustion heat of the input combustion gas, and supplies the heated gas medium as the heated gas to the carbon dioxide release reactor .

In order for carbon dioxide contained in the gas to be treated to be absorbed by the carbon dioxide absorbent in the carbon dioxide absorption reactor, it is necessary to preheat the gas to be treated to a high temperature. The temperature of the processing gas after the carbon dioxide contained in the gas to be processed is absorbed by the carbon dioxide absorbent in a high temperature state is high. Using the processing gas heat recovery device, the heat of the processing gas is recovered and supplied to the processing gas preheater. That is, a part of the thermal energy supplied from the outside to the processing gas preheater is reused by the processing gas preheater.
Therefore, the heat energy to be supplied to the gas preheater to be processed from outside the gas processing apparatus can be saved.

  According to another aspect of the present invention, in the gas treatment device of the present invention, the carbon dioxide absorbent preferably includes at least one of potassium carbonate and sodium carbonate and a lithium composite oxide.

  In the gas processing apparatus having such a configuration, the carbon dioxide absorbent that has been absorbed by the heated gas is heated to release carbon dioxide, so that the released carbon dioxide output from the carbon dioxide release reactor is at a high temperature. The heat of the released carbon dioxide is recovered by a released gas heat recovery device and used for preheating the heated gas medium. Therefore, the thermal energy of the combustion gas supplied to the heated gas generator from the outside of the gas processing apparatus can be saved.

  Moreover, in another invention, the carbon dioxide concentration of discharge | released carbon dioxide can be raised by supplying a part of discharge | released carbon dioxide to a heating gas preheater as a heating gas medium.

  Furthermore, in another invention, the combustion gas preheater which preheats the combustion gas containing at least any one of carbon containing fuel and hydrogen containing gas, and oxygen gas is provided. The heated gas generator heats the combustion gas preheated by the combustion gas preheater and supplies it as a heated gas to the carbon dioxide release reactor.

  Furthermore, in another invention, it is included in the gas to be treated introduced into the carbon dioxide absorption reactor by providing a desulfurization step in the path from the input in the gas to be treated to the introduction into the carbon dioxide absorption reactor. Impure gas components such as sulfurous acid gas components can be removed.

  Furthermore, in another invention, the structure of the carbon dioxide absorption reactor and the carbon dioxide release reactor and the storage form of the carbon dioxide absorbent are made the same, and the absorption and release of carbon dioxide is performed by switching the gas flow path. A gas flow path switching means that is alternately provided between the absorption reactor and the carbon dioxide release reactor is provided.

  By comprising in this way, it is not necessary to move the absorbed carbon dioxide absorber in which the carbon dioxide was absorbed in the carbon dioxide absorption reactor to the carbon dioxide release reactor. Furthermore, it is not necessary to move the carbon dioxide absorbent after the carbon dioxide is released in the carbon dioxide release reactor to the carbon dioxide absorption reactor.

Furthermore, in another invention, the carbon dioxide absorption material and the absorbed carbon dioxide absorption material are circulated and transferred between the carbon dioxide absorption reactor and the carbon dioxide release reactor to thereby absorb and release carbon dioxide. Absorbent transfer means for alternately performing between the absorption reactor and the carbon dioxide release reactor is provided.
By comprising in this way, the substantially same effect as previous invention can be show | played.

  Furthermore, in another invention, the number of carbon dioxide absorption reactors is two or more, and the carbon dioxide absorbent after release of carbon dioxide stored in a carbon dioxide absorption reactor disposed upstream of the flow path of the gas to be treated This heat is used for preheating the gas to be processed.

  Furthermore, in another invention, the number of carbon dioxide releasing reactors is two or more, and the heat of the heated gas discharged from the carbon dioxide releasing reactor disposed upstream of the heating gas flow path is set downstream. It is used for preheating the temperature of the absorbed carbon dioxide absorbent in the disposed carbon dioxide release reactor.

  Thus, by providing two or more carbon dioxide absorption reactors or carbon dioxide release reactors, the temperature of the gas to be treated can be increased efficiently, and the temperature of the absorbed carbon dioxide absorbent can be increased efficiently. .

  Furthermore, in another invention, the lithium composite oxide is desirably at least one lithium composite oxide selected from lithium silicate, lithium zirconate, and lithium ferrite.

  Furthermore, in another invention, it is possible to produce at least one of water vapor and hot water using the recovered heat recovered at least one of the process gas heat recovery device and the emission gas heat recovery device. desirable.

  Furthermore, in another invention, it is desirable to use the recovered heat recovered in at least one of the process gas heat recovery device and the emission gas heat recovery device in the power generation system.

  Furthermore, in another invention, it is desirable to use the recovered heat recovered in at least one of the process gas heat recovery device and the emission gas heat recovery device in the hydrogen production system.

  Furthermore, in another invention, it is desirable to supply the liquefied carbon dioxide production system with the released carbon dioxide output from the carbon dioxide releasing reactor and heat-recovered by the released gas heat recovery device.

  In the gas processing apparatus configured as described above, the heat energy supplied from the outside necessary for the reaction for separating and recovering the carbon dioxide contained in the gas to be processed is reused without being released to the outside. Therefore, the energy required for carbon dioxide recovery can be reduced, and the energy efficiency of this gas processing apparatus can be improved.

  Furthermore, by supplying the recovered thermal energy to carbon-containing fuel combustion processes such as power generation and boilers that are carbon dioxide generation sources, hydrogen production steam reforming processes of carbon-containing fuels, heating of biogas processes, etc., The energy efficiency of the entire energy system from carbon dioxide generation to carbon dioxide recovery can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic diagram showing a schematic configuration of a gas processing apparatus according to the first embodiment of the present invention.

A processing target gas 1 containing carbon dioxide input from the outside is preheated by a processing target gas preheater 2. The to-be-processed gas 1 containing carbon dioxide shown in this embodiment refers to all carbon dioxide-containing gases produced or discharged industrially, for example, combustion exhaust gas of power generation / boiler carbon-containing fuel, water vapor obtained from carbon-containing combustion There are reformed gas, exhaust gas in various industrial processes using carbon dioxide, biogas and the like.
The to-be-treated gas preheater 2 may be a device having a known gas heating ability capable of preheating the to-be-treated gas 1 to an arbitrary set temperature range in a range of 20 to 700 ° C. If a model suitable for the purpose is selected. Good. A plurality of gas preheaters 2 to be processed may be arranged along the flow path of the gas to be processed 1. Furthermore, if heat recovered by the gas processing apparatus is used as a part of the heat source of the gas preheater 2 to be processed, there is an effect of reducing energy consumption in the gas processing apparatus, which is more preferable.
The to-be-treated gas 1 preheated in the to-be-treated gas preheater 2 is supplied to the carbon dioxide absorption reactor 6 filled with the carbon dioxide absorbent 5 via the pipe 3a and the opened valve 6a. Part of the carbon dioxide contained in 1 is absorbed by the carbon dioxide absorbent 5. As the carbon dioxide absorbent 5, it is preferable to use, for example, a lithium composite oxide represented by lithium silicate, lithium zirconate, and lithium ferrite.
Lithium zirconate has a chemical formula of Li ₂ ZrO ₃ and Li ₄ ZrO ₄ , and lithium ferrite has a chemical formula of LiFeO ₂ . As lithium silicates, lithium metasilicate (Li ₂ SiO ₃ ) and lithium orthosilicate (Li ₄ SiO ₄ ) are known. The reaction of the following formula in which this lithium orthosilicate absorbs carbon dioxide CO ₂ is particularly suitable.
Li ₄ SiO ₄ + CO ₂ = Li ₂ SiO ₂ + Li ₂ CO ₃
In addition, examples of the structural form of the carbon dioxide absorbent 5 include fine particles, lumps, spheres, pellets, honeycombs, meshes, and the like, but a structural form that matches the operation mode of the reaction may be selected.
As the carbon dioxide absorbent 5, it is possible to include potassium carbonate or sodium carbonate, or both potassium carbonate and sodium carbonate in addition to the lithium composite oxide.

The reaction temperature between the carbon dioxide absorbent 5 and carbon dioxide in the carbon dioxide absorption reactor 6 may be determined from the composition of the carbon dioxide absorbent 5 and the composition of the gas 1 to be treated. For example, when the lithium composite oxide contained in the carbon dioxide absorbent 5 is lithium silicate and the carbon dioxide concentration of the gas to be treated 1 is 5 to 10%, the reaction temperature is preferably 500 to 650 ° C. The reaction temperature is preferably 520 to 600 ° C. when the atmospheric pressure in the carbon dioxide absorption reactor 6 is 1 atm.
In order to maintain the temperature in the carbon dioxide absorption reactor 6, it is also preferable to arrange heating means as appropriate. The heating means may be selected in accordance with the operation mode of the gas processing apparatus.
Further, a desulfurization step is inserted in the path of the gas to be treated 1 to the carbon dioxide absorption reactor 6, and impure gas components such as sulfurous acid gas components contained in the gas to be treated 1 supplied to the carbon dioxide absorbent 5 are added. It is preferable to remove.
In the carbon dioxide absorption reactor 6, the processing gas 7 after the carbon dioxide is absorbed by the carbon dioxide absorbent 5 is heated in the processing gas heat recovery device 8 via the opened valve 6c and the pipe 3b. Collected. The heat recovered by the processing gas heat recovery device 8 is supplied to the processing gas preheater 2. The to-be-treated gas preheater 2 preheats the to-be-treated gas 1 with heat obtained by adding heat recovered by the processing gas heat recovery device 8 to heat supplied from the outside.

As described above, when the recovered heat obtained by the processing gas heat recovery device 8 is used in the to-be-processed gas preheater 2 disposed in the gas processing device, there is an effect of reducing energy consumption in the gas processing device, which is more preferable. It is.
The process gas heat recovery unit 8 may be of any type, and for example, heat recovery using steam, hot water or the like can be performed. Further, a plurality of process gas heat recovery units 8 may be arranged.

  The valve 6b of the pipe 3c that connects the carbon dioxide absorption reactor 6 and the emission gas heat recovery unit 9 is closed, and the valve 6d of the pipe 3d that connects the carbon dioxide absorption reactor 6 and the heated gas generator 10 also. It is closed.

  The carbon dioxide release reactor 12 contains an absorbed carbon dioxide absorbent 11 that has absorbed carbon dioxide. The carbon dioxide release reactor 12 is supplied with the heated gas 13 from the heated gas generator 10 through the pipe 3d and the opened valve 12d. When the absorbed carbon dioxide absorbent 11 is heated by the heated gas 13, it releases high-temperature carbon dioxide. The released high temperature carbon dioxide is supplied as released carbon dioxide 14 to the released gas heat recovery unit 9 through the opened valve 12b and the pipe 3c.

  The released gas heat recovery unit 9 recovers the heat of the released carbon dioxide 14 and supplies it to the heated gas preheater 15. The heated gas preheater 15 preheats the heated gas medium 16 made of, for example, carbon dioxide supplied from the outside and supplies the heated gas medium 10 to the heated gas generator 10.

  The carbon-containing combustion and / or hydrogen-containing fuel 17 and the oxygen-containing gas 18 are preheated by the combustion gas preheaters 19a and 19b, respectively, and supplied to the heated gas generator 10. The heated gas generator 10 heats the heated gas medium 16 with the combustion heat of the supplied carbon-containing combustion and / or the hydrogen-containing fuel 17 and the oxygen-containing gas 18 and supplies the heated gas medium 16 as the heated gas 13 to the carbon dioxide release reactor 12. To do. The heat of the combustion gas 21 after heating the heated gas medium 16 in the heated gas generator 10 is recovered by the combustion gas heat recovery device 20.

  Note that the valve 12a of the pipe 3a connecting the carbon dioxide releasing reactor 12 and the gas preheater 2 to be processed is closed, and the valve 12c of the pipe 3b connecting the carbon dioxide releasing reactor 12 and the processing gas heat recovery unit 8 is also used. It is closed.

The type of the combustion gas preheater 19a, 19b may be selected according to the purpose, and using the heat recovered in the gas processing apparatus has the effect of reducing energy consumption in the entire gas processing apparatus, and is more preferable. It is.
The oxygen-containing gas 18 may be arbitrarily selected from oxygen, air, etc. according to the utilization form of the carbon dioxide to be recovered. Moreover, the combustion gas preheaters 19a and 19b may be incorporated in the heated gas generator 10 and have a function of preheating gas serving as a heating source.

  As described above, the heated gas 13 raises and holds the absorbed carbon dioxide absorbent 11 in the carbon dioxide release reactor 12. The temperature and flow rate of the heated gas 13 may be arbitrarily set within a range in which carbon dioxide is released from the absorbed carbon dioxide absorbent 11 and the material does not deteriorate.

Further, the temperature rise / holding temperature of the absorbed carbon dioxide absorbent 11 may be set in accordance with the carbon dioxide partial pressure of the heated gas 13, the material, and the planned amount of carbon dioxide emission. For example, when the carbon dioxide absorbent 5 is lithium silicate, it is preferable to set the temperature rise / holding temperature of the released carbon dioxide absorbent 11 in the range of 700 to 850 ° C.
The released gas heat recovery unit 9 that recovers the heat of the released carbon dioxide 14 released from the released carbon dioxide absorbent 11 may be of any type, and performs heat recovery using, for example, steam or hot water. It is also possible. FIG. 1 shows heat exchange with a heated gas preheater 15 that preheats the heated gas medium 16. Further, a plurality of emission gas heat recovery devices 9 may be arranged.
Thus, it is more preferable to use the recovered heat obtained by the released gas heat recovery unit 9 in the preheater disposed in the gas processing apparatus, because it has an effect of reducing energy consumption in the gas processing apparatus.
Further, a part of the released carbon dioxide 14 can be used as the heated gas medium 16. When a part of the released carbon dioxide 14 is used for the heated gas medium 16, the purity of the recovered released carbon dioxide 14 is improved, and the purification process load when the recovered carbon dioxide 14 is liquefied and purified is reduced. This is preferable because of the effect.
The combustion gas heat recovery unit 20 that recovers the heat of the combustion gas 21 exhausted from the heating gas generator 10 may be of any type, and for example, heat recovery using steam, hot water, or the like may be performed. A plurality of them may be arranged. It is also possible to incorporate this combustion gas heat recovery device 20 into the heating gas generator 8.

When the heat recovered by the combustion gas heat recovery unit 20 is used in the above-described preheaters 2, 15, 19a, and 19b disposed in the gas processing apparatus, there is an effect of reducing energy consumption in the gas processing apparatus. Is more preferable.
The gas processing apparatus shown in FIG. 1 has a function of switching the operation mode of carbon dioxide absorption / release in the carbon dioxide absorption reactor 6 and the carbon dioxide release reactor 12 by switching the gas flow path. Since the absorption and release of carbon dioxide are switched by this gas flow path, the structure of the carbon dioxide absorption reactor 6 and the carbon dioxide release reactor 12, the structure of the carbon dioxide absorbent 5, the structure of the absorbed carbon dioxide absorbent 11, and the filling form The functions are the same. Further, the carbon dioxide absorption reactor 6 and the carbon dioxide release reactor 12 shown in FIG. 1 may be either a fixed bed or a fluidized bed.
Specifically, the carbon dioxide absorption reactor 6 absorbs carbon dioxide by controlling the opening and closing of the valves 6a to 6d and 12a to 12d so that the gas flows through the pipe shown by the thick line in FIG. Carbon dioxide is released in the carbon release reactor 12. When the absorption / release of carbon dioxide is completed, the carbon dioxide absorption reactor 6 controls the opening and closing of the valves 6a to 6d and 12a to 12d so that the gas flows through the pipe shown by the thick line in FIG. The carbon dioxide release reactor 12 performs carbon dioxide absorption. In FIG. 2, the valves 6b, 6d, 12a and 12c are opened, and the valves 6a, 6c, 12b and 12d are closed. In this case, the released carbon dioxide absorbent 11 exists in the carbon dioxide absorption reactor 6, and the carbon dioxide absorbent 5 exists in the carbon dioxide release reactor 12.

  Therefore, it is not necessary to move the absorbed carbon dioxide absorbent 11 that has absorbed carbon dioxide in the carbon dioxide absorption reactor 6 to the carbon dioxide release reactor 12. Furthermore, it is not necessary to move the carbon dioxide absorbent 5 after the carbon dioxide is released in the carbon dioxide release reactor 12 to the carbon dioxide absorption reactor 6.

(Second Embodiment)
FIG. 3 is a schematic diagram showing a schematic configuration of a gas processing apparatus according to the second embodiment of the present invention. The same parts as those in the gas processing apparatus of the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and detailed description of the overlapping parts is omitted.

  In the gas processing apparatus of the second embodiment, compared to the gas processing apparatus of the first embodiment, the cooling process reactor 22 that stores the released carbon dioxide absorbent 5a, and the absorbed carbon dioxide absorbent 11a before temperature increase. And a temperature raising step reactor 23 containing

Next, the operation and action of the gas processing apparatus of the second embodiment will be described.
The to-be-treated gas 1 preheated by the to-be-treated gas preheater 2 is first introduced into the cooling process reactor 22 that is filled with the released carbon dioxide absorbent 5a in a high temperature state from which carbon dioxide has been released. Thereafter, the exhaust gas (processed gas 1) of the cooling process reactor 22 is introduced into the carbon dioxide absorption reactor 6 filled with the carbon dioxide absorbent 5. The process gas 7 discharged from the carbon dioxide absorption reactor 6 is recovered by the process gas heat recovery unit 8. The heat recovered by the processing gas heat recovery device 8 is supplied to the processing gas preheater 2.

In the temperature comparison of the absorption and release of carbon dioxide, the release reaction is maintained at a higher temperature than the absorption reaction. Therefore, the temperature of the released carbon dioxide absorbent 5a after the release reaction is higher than that of the carbon dioxide absorbent 5. Yes. The high temperature of the released carbon dioxide absorbent 5a is used for preheating the gas 1 to be treated, and at the same time, the released carbon dioxide absorbent 5a is cooled. Therefore, the heat in the gas processing apparatus can be used efficiently.
The heated gas 13 supplied to the carbon dioxide release reactor 12 filled with the absorbed carbon dioxide absorbent 11 is used to heat the absorbed carbon dioxide 11 and release the carbon dioxide, and then absorbs carbon dioxide before the temperature rise after absorption. It is supplied to the temperature raising step reactor 23 filled with the absorbent 11a. Carbon dioxide is released from the absorbed carbon dioxide absorbent 11a before the temperature rise in the temperature raising step reactor 23, and is sent to the released gas heat recovery device 9 as released carbon dioxide 14.

  The released gas heat recovery unit 9 recovers the heat of the released carbon dioxide 14 and supplies it to the heated gas preheater 15. The heated gas preheater 15 preheats the heated gas medium 16 made of, for example, carbon dioxide supplied from the outside and supplies the heated gas medium 10 to the heated gas generator 10.

As described above, since the release reaction is preferably maintained at a higher temperature than the absorption reaction as described above, the heat of the released carbon dioxide discharged from the carbon dioxide release reactor 12 is reduced with respect to the carbon dioxide absorption / release temperature. After the carbon absorption reaction, it is supplied to the carbon dioxide absorbent 11a before being heated in the temperature rising process reactor 23, which is at a lower temperature than the carbon dioxide releasing reactor 12. As a result, it is possible to raise the temperature of the carbon dioxide absorbent 11a before being heated by the heat of the released carbon dioxide, and the heat in the gas processing apparatus can be used efficiently.
As described above, the reaction process in each of the reactors 6, 22, 12, and 23 in the gas processing apparatus shown in FIG. 3 is performed by converting carbon dioxide contained in the gas to be processed into the carbon dioxide absorbent 5 as shown in FIG. A step of absorbing the carbon dioxide absorbed (absorption step), a step of raising the temperature of the absorbent 11 that has absorbed carbon dioxide to the carbon dioxide release temperature (a temperature raising step), and a step of releasing carbon dioxide from the heated carbon dioxide absorbed absorber 11a (Release step), which consists of four steps of cooling the released carbon dioxide absorbent 5a to the carbon dioxide absorption temperature (cooling step).
These four steps are repeated by switching the gas flow path by controlling the opening and closing of the valves of the pipes attached to the reactors 6, 22, 12, and 23. FIG. 5 shows a temperature change in each step shown in FIG. Therefore, this temperature change is repeated.

In this way, the operation shown in FIGS. 4 and 5 can be performed by switching the introduction / outflow gas paths for the respective reactors 6, 22, 12, and 23 so that the respective reactors become different processes. Well, for example, it is preferable to repeat the operation as shown in FIG. 6 when performing the four steps using four reactors.
Here, it is desirable that the structures and functions of the cooling process reactor 22, the temperature raising process reactor 23, the carbon dioxide absorption reactor 6, and the carbon dioxide release reactor 12 are the same. Furthermore, it is preferable that the filling form, function, and structure of the carbon dioxide absorbing material 5, the released carbon dioxide absorbing material 5a, the absorbed carbon dioxide absorbing material 11, and the absorbed carbon dioxide absorbing material 11a before temperature increase are also equivalent. .
Furthermore, the carbon dioxide absorption reactor 6, the cooling process reactor 22, the carbon dioxide release reactor 12, and the temperature raising process reactor 23 may be either a fixed bed or a fluidized bed.
(Third embodiment)
FIG. 7 is a schematic diagram showing a schematic configuration of a gas processing apparatus according to the third embodiment of the present invention. The same parts as those in the gas processing apparatus of the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and detailed description of the overlapping parts is omitted.

  In the gas processing apparatus of the third embodiment, in the gas processing apparatus of the first embodiment shown in FIG. 1, the combustion gas that generates the heating gas 13a supplied to the carbon dioxide release reactor 12 by the heating gas generator 10a. It is said.

Next, the operation and action of the gas processing apparatus of the third embodiment will be described.
The heated gas generator 10a combusts the carbon-containing fuel and / or the hydrogen-containing fuel gas 17 preheated by the combustion gas preheater 19a and the oxygen-containing gas 18 preheated by the combustion gas preheater 19a. The resulting combustion gas is supplied to the carbon dioxide release reactor 12 that is filled with the carbon dioxide absorbent 11 that has absorbed the heated gas 13a.

  In this case, as the oxygen concentration of the oxygen-containing gas 18 is higher, the carbon dioxide purity of the released carbon dioxide 14 released from the carbon dioxide release reactor 12 is improved. Furthermore, it is preferable because the effect of reducing the load of the purification process when the recovered carbon dioxide 14 is liquefied and refined is produced. Further, the heated gas generator 10 a can be incorporated into the carbon dioxide release reactor 12.

  Similarly to the gas processing apparatus of the first embodiment, the gas processing apparatus of the third embodiment absorbs carbon dioxide in the carbon dioxide absorption reactor 6 and the carbon dioxide release reactor 12 by switching the gas flow path. It has a function to switch the operation mode of discharge.

  Also in the gas processing apparatus of the third embodiment configured as described above, it is possible to achieve substantially the same operational effects as those of the gas processing apparatus of the first embodiment described above.

(Fourth embodiment)
FIG. 8 is a schematic diagram showing a schematic configuration of a gas processing apparatus according to the fourth embodiment of the present invention. The same parts as those in the gas processing apparatus of the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and detailed description of the overlapping parts is omitted.

  In the gas processing apparatus of the fourth embodiment, in the gas processing apparatus of the first embodiment shown in FIG. 1, the carbon dioxide by switching the gas flow path provided in the carbon dioxide absorption reactor 4 and the carbon dioxide release reactor 12. Piping and valves for switching carbon absorption / release operation have been removed. An absorbed absorbent transfer path 24 and a discharged absorbent transfer path 25 are provided.

Next, the operation and action of the gas processing apparatus according to the fourth embodiment will be described.
The carbon dioxide absorbent 5 that has absorbed carbon dioxide in the carbon dioxide absorption reactor 6 is transferred to the carbon dioxide release reactor 12 through the absorbed absorbent transfer path 24 as the absorbed carbon dioxide absorbent 11. The absorbed absorbent transfer path 24 may be of any type. For example, when the carbon dioxide absorption reactor 6 and the carbon dioxide release reactor 12 are fluidized bed / moving bed reactors, gravity drop, air lift, conveyor, etc. is there.
An absorbent cooling process or the like may be provided in the absorbed absorbent transfer path 24 as appropriate. When heat is recovered by the transfer of the absorbent material, it is more desirable that the recovered heat is used in each of the preheaters 2 and 10 provided in the gas processing apparatus.
The absorbed carbon dioxide absorbent 11 that has released carbon dioxide in the carbon dioxide release reactor 12 is transferred as the carbon dioxide absorbent 5 to the carbon dioxide absorption reactor 6 via the released absorbent transfer path 25. The discharged absorbent material transfer path 25 may be of any type. For example, when the carbon dioxide absorption reactor 6 and the carbon dioxide release reactor 12 are fluidized bed / moving bed reactors, gravity drop, air lift, conveyor, etc. is there.
An absorbent cooling process or the like may be provided in the discharged absorbent material transfer path 25 as appropriate. When heat is recovered by the transfer of the absorbent material, it is more desirable that the recovered heat is used in each of the preheaters 2 and 10 provided in the gas processing apparatus.
When the carbon dioxide absorption reactor 6 and the carbon dioxide release reactor 12 are fluidized bed / moving bed reactors, structural deterioration due to wear or the like may occur due to transfer of the absorbent material and movement of the absorbent material in the reactor. It is preferable to take a form that does not occur. In addition, it is also preferable that an absorbent material supply / discharge path for exchanging the absorbent material or the like is disposed in the absorbent material transfer paths 24 and 25.
In the gas processing apparatus of the fourth embodiment configured as described above, the absorption and release of carbon dioxide is performed by providing the absorbed absorbent transfer path 24 and the released absorbent transfer path 24, thereby absorbing the carbon dioxide. 6 and the carbon dioxide releasing reactor 12 can be alternately performed. Accordingly, it is possible to achieve substantially the same operational effects as those of the gas processing apparatus of the first embodiment described above.

The present invention is not limited to the above-described embodiments.
The recovered heat recovered by the process gas heat recovery device 8 and the emitted gas heat recovery device 9 can be used for a power generation system and a hydrogen production system.

The schematic diagram which shows schematic structure of the gas processing apparatus concerning 1st Embodiment of this invention. The schematic diagram which shows switching operation | movement of the gas flow path of the gas processing apparatus concerning the 1st embodiment The schematic diagram which shows schematic structure of the gas processing apparatus concerning 2nd Embodiment of this invention. The schematic diagram which shows the carbon dioxide collection process in the gas processing apparatus concerning the said 2nd Embodiment Schematic diagram showing carbon dioxide recovery process and temperature range in the gas processing apparatus according to the second embodiment Schematic diagram showing each reactor and carbon dioxide recovery step in the gas processing apparatus according to the second embodiment The schematic diagram which shows schematic structure of the gas processing apparatus concerning 3rd Embodiment of this invention. The schematic diagram which shows schematic structure of the gas processing apparatus concerning 4th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Processed gas, 2 ... Processed gas preheater, 3a-3d ... Piping, 5 ... Carbon dioxide absorber, 5a ... Released carbon dioxide absorber, 6 ... Carbon dioxide absorption reactor, 7 ... Process gas, 8 ... Process gas heat recovery device, 9 ... Emission gas heat recovery device, 10, 10a ... Heated gas generator, 11 ... Absorbed carbon dioxide absorber, 11a ... Absorbed carbon dioxide absorber before temperature increase, 12 ... Release of carbon dioxide Reactor 13, 13a ... heated gas, 14 ... released carbon dioxide, 15 ... heated gas preheater, 16 ... heated gas medium, 17 ... carbon-containing and / or hydrogen-containing fuel gas, 18 ... oxygen-containing gas, 19a, 19b ... Combustion gas preheater, 20 ... Combustion gas heat recovery device, 21 ... Combustion gas, 22 ... Cooling process reactor, 23 ... Temperature rising process reactor, 24 ... Absorbed absorbent transport path, 25 ... Released absorbent Transfer route

Claims (14)

In a gas processing apparatus that separates and recovers and outputs a part of carbon dioxide contained in the input gas to be processed,
A process gas preheater for preheating the input process gas;
A carbon dioxide absorbent containing at least a lithium composite oxide that reversibly absorbs and releases carbon dioxide is housed, and carbon dioxide contained in the gas to be treated preheated by the gas to be treated preheater is used as the carbon dioxide absorbent. A carbon dioxide absorption reactor to be absorbed,
A process gas heat recovery unit that recovers heat of the process gas after carbon dioxide discharged from the carbon dioxide absorption reactor is absorbed and supplies the heat to the gas preheater to be processed;
A carbon dioxide releasing reactor in which the absorbed carbon dioxide absorbing material in a state of absorbing carbon dioxide is stored, and the absorbed carbon dioxide absorbing material is heated by a supplied heated gas to release carbon dioxide;
A heated gas generator for generating heated gas to be supplied to the carbon dioxide release reactor;
A released gas heat recovery device for recovering the heat of the released carbon dioxide output from the carbon dioxide release reactor ;
A heated gas preheater for preheating the heated gas medium with the heat recovered by the emitted gas heat recovery device,
The heated gas generator is preheated by the heated gas preheater according to the combustion heat of the input combustion gas.
A gas processing apparatus , wherein a heated heated gas medium is heated and supplied to the carbon dioxide releasing reactor as a heated gas . The gas processing apparatus according to claim 1, wherein the carbon dioxide absorbent includes at least one of potassium carbonate and sodium carbonate and a lithium composite oxide. Wherein a portion of the emitted carbon dioxide and supplying to the heating gas preheater as the heating gas medium according to claim 1 Gas treatment apparatus as claimed. A combustion gas preheater for preheating combustion gas containing at least one of carbon-containing fuel and hydrogen-containing gas and oxygen gas;
The heating gas generator, the combustion gas preheater to heat the preheated combustion gas and supplying to the carbon dioxide emissions reactor as heating gas claim 1 Symbol placement of the gas treatment apparatus. The gas processing apparatus according to any one of claims 1 to 4 , further comprising a desulfurization step in a path from input to the gas to be processed to introduction into the carbon dioxide absorption reactor. Wherein the housing forms a structural and carbon dioxide absorbent of the carbon dioxide absorption reactor and the carbon dioxide emission reactor identical, said by switching the gas flow path, the absorption and release of carbon dioxide and the carbon dioxide absorption reactor The gas processing apparatus according to any one of claims 1 to 5 , further comprising gas flow path switching means that is alternately provided between the carbon dioxide release reactor and the carbon dioxide release reactor. By circulating transfer between the carbon dioxide absorbent and absorbed already carbon dioxide absorbent of the carbon dioxide emissions reactor and the carbon dioxide absorption reactor, the absorption and release of carbon dioxide and the carbon dioxide absorption reactor The gas processing apparatus according to any one of claims 1 to 5 , further comprising an absorbent material transfer means that alternately performs with the carbon dioxide release reactor. The number of carbon dioxide absorption reactors is two or more, and the heat of the carbon dioxide absorbing material after the carbon dioxide release stored in the carbon dioxide absorption reactor disposed upstream of the flow path of the gas to be treated is treated. gas treatment apparatus according to any one of claims 1, characterized in that used for the process gas preheater 5. The number of the carbon dioxide emissions reactor and two or more, the carbon dioxide the heat of the heating gas discharged, is disposed downstream from the carbon dioxide emission reactor arrangement upstream of the flow path of the heated gas The gas processing apparatus according to any one of claims 1 to 5 , wherein the gas processing apparatus is used for preheating the temperature of the absorbed carbon dioxide absorbent in the release reactor. The gas treatment apparatus according to any one of claims 1 to 9 , wherein the lithium composite oxide is at least one lithium composite oxide selected from lithium silicate, lithium zirconate, and lithium ferrite. Claim 1, characterized in that by utilizing the recovered heat is at least recovered by either one of the discharge gas heat recovery device and the treated gas heat recovery device, to produce at least one of steam and hot water The gas treatment device according to any one of 1 to 10 . Gas treatment according to any one of claims 1 to 10, characterized in that utilizing the recovered heat is at least recovered by either one of the discharge gas heat recovery device and the treated gas heat recovery device to the power generation system apparatus. Set forth in any one gas of claims 1 to 10, characterized in that utilizing the recovered heat is at least recovered by either one of the discharge gas heat recovery device and the treated gas heat recovery device to the hydrogen production system Processing equipment. The gas according to any one of claims 1 to 10 , wherein the released carbon dioxide output from the carbon dioxide releasing reactor and heat-recovered by the released gas heat recovery device is supplied to a liquefied carbon dioxide production system. Processing equipment.

Images