CN115671951B - Carbon dioxide combined capturing method - Google Patents
Carbon dioxide combined capturing method Download PDFInfo
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- CN115671951B CN115671951B CN202210845556.5A CN202210845556A CN115671951B CN 115671951 B CN115671951 B CN 115671951B CN 202210845556 A CN202210845556 A CN 202210845556A CN 115671951 B CN115671951 B CN 115671951B
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
- Y02C20/00—Capture or disposal of greenhouse gases
- Y02C20/40—Capture or disposal of greenhouse gases of CO2
Abstract
The invention belongs to the technical field of environmental protection, and particularly relates to a carbon dioxide combined capturing method, which comprises biomass carbon adsorption, biochar composite material adsorption and spherical honeycomb type metal material adsorption; a gas humidity monitoring step is also arranged between the biomass carbon composite material adsorption step and the spherical honeycomb type metal material adsorption step, and the mass percentage of water vapor in the gas entering the spherical honeycomb type metal material adsorption step after the biomass carbon composite material adsorption is less than 4%; the high-concentration carbon dioxide desorbed by the biological carbon adsorption and biomass carbon composite material is subjected to the next adsorption step, the high-concentration carbon dioxide gas desorbed by the spherical honeycomb metal material adsorption step is recovered, and the tail gas desorbed by the biomass carbon adsorption, the biological carbon composite material adsorption and the spherical honeycomb metal material adsorption step is subjected to the biomass carbon adsorption again. The method of the invention can circularly adsorb and has low cost.
Description
Technical Field
The invention relates to the technical field of environmental protection, in particular to a carbon dioxide combined capturing method.
Background
The description of the background of the invention pertaining to the related art to which this invention pertains is given for the purpose of illustration and understanding only of the summary of the invention and is not to be construed as an admission that the applicant is explicitly or implicitly admitted to be prior art to the date of filing this application as first filed with this invention.
With the development of economic society, the artificial carbon dioxide emission in the atmosphere is increasing. The accumulation of carbon dioxide in the atmosphere can lead to a number of climatic and environmental disasters. Such as global warming, sea level elevation, land desertification, and the like. Meanwhile, carbon dioxide is used as a potential carbon resource and has wide application in the fields of chemistry and agriculture. Therefore, carbon dioxide capture and separation is the best option to mitigate current greenhouse gas emissions and to recover this potential carbon resource. In particular, the capture and separation of carbon dioxide from large flue gas sources, such as coal-fired power plants and cement plants, is critical to reducing carbon dioxide emissions. Among the existing carbon dioxide capture methods, the solid amine adsorption method has a wide application prospect due to high selectivity and low regeneration energy consumption.
The selectivity of physical adsorption in the current carbon dioxide capture is not high, and the metal framework adsorption has the problem of high cost.
Disclosure of Invention
The embodiment of the invention aims to provide a
A carbon dioxide combined capturing method is characterized by comprising biomass charcoal adsorption, charcoal composite material adsorption and spherical honeycomb type metal material adsorption; a gas humidity monitoring step is also arranged between the biomass carbon composite material adsorption step and the spherical honeycomb type metal material adsorption step, and the mass percentage of water vapor in the gas entering the spherical honeycomb type metal material adsorption step after the biomass carbon composite material adsorption is less than 4%; the high-concentration carbon dioxide desorbed by the biological carbon adsorption and biomass carbon composite material is subjected to the next adsorption step, the high-concentration carbon dioxide gas desorbed by the spherical honeycomb metal material adsorption step is recovered, and the tail gas desorbed by the biomass carbon adsorption, the biological carbon composite material adsorption and the spherical honeycomb metal material adsorption step is subjected to the biomass carbon adsorption again.
Further, the biomass charcoal adopted by the biomass charcoal composite material for adsorption is treated by the following steps: crushing corn straw biochar, and then sequentially soaking 1-aminoethyl-3-methylimidazole bromine salt solution and polyacrylamide; wherein the mass ratio of the corn stalk biochar, the 1-aminoethyl-3-methylimidazole bromine salt and the polyacrylamide is (10).
Further, the biomass charcoal in the biomass charcoal composite material adsorption also has a surface stripping step before the impregnation step, and is used for improving the proportion of surface functional groups.
Further, the spherical honeycomb metal material is prepared by loading tetraethylenepentamine on the exposed surface of a honeycomb structure of MOFs according to the mass ratio of MOFs to tetraethylenepentamine being 1.
Further, a carbon dioxide concentration monitoring step is arranged after the adsorption step of the spherical honeycomb type metal material: setting the lower limit of the concentration of the carbon dioxide tail gas as T, and the upper limit of water vapor in the gas after the biomass carbon composite material is adsorbed as M, wherein M is not more than 4%; and when the concentration of the carbon dioxide in the tail gas is less than T, regulating and controlling to reduce M, but controlling the ratio of M/T to be not less than a set value N.
The embodiment of the invention has the following beneficial effects:
the method reduces the content of the water vapor in the gas by adopting biomass carbon adsorption, further can naturally reduce the water vapor content of the gas entering the spherical honeycomb metal material in the combined adsorption, further does not need a step of drying the gas, reduces the adsorption cost, and further reduces the gas adsorption cost as much as possible on the premise of meeting the gas emission purity by controlling the ratio of the carbon dioxide content in the final gas to the water vapor content in the intermediate step.
Detailed Description
The present application is further described below with reference to examples.
In the following description, different "one embodiment" or "an embodiment" may not necessarily refer to the same embodiment, in order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art. Various embodiments may be replaced or combined, and other embodiments may be obtained according to the embodiments without creative efforts for those skilled in the art.
A carbon dioxide combined capturing method is characterized by comprising biomass charcoal adsorption, charcoal composite material adsorption and spherical honeycomb type metal material adsorption; a gas humidity monitoring step is also arranged between the biomass carbon composite material adsorption step and the spherical honeycomb type metal material adsorption step, and the mass percentage of water vapor in the gas entering the spherical honeycomb type metal material adsorption step after the gas is adsorbed by the biomass carbon composite material is less than 4%; the high-concentration carbon dioxide desorbed by the biological carbon adsorption and biomass carbon composite material is subjected to the next adsorption step, the high-concentration carbon dioxide gas desorbed by the spherical honeycomb metal material adsorption step is recovered, and the tail gas desorbed by the biomass carbon adsorption, the biological carbon composite material adsorption and the spherical honeycomb metal material adsorption step is subjected to the biomass carbon adsorption again.
In some embodiments of the present invention, the biomass charcoal used for adsorbing the biomass charcoal composite material is treated by the following steps: crushing corn stalk charcoal, and then sequentially soaking 1-aminoethyl-3-methylimidazole bromine salt solution and polyacrylamide; wherein the mass ratio of the corn stalk biochar to the 1-aminoethyl-3-methylimidazole bromine salt to the polyacrylamide is 10.
It should be noted here that the biomass charcoal needs to be fluffy to achieve adsorption better, and the corn straw biomass charcoal is high in fluffy degree, so that a microporous structure is formed, adsorption is facilitated, and the impregnation step by step is also facilitated to be uniform.
In order to further increase the fluffiness, the corn cob biomass charcoal can be added into the corn stalk biomass charcoal, but it should be noted that the mass content of the corn cob biomass charcoal should not be more than 50%, because the corn cob biomass charcoal has fluffy characteristics, but is soft in texture, and too high proportion can cause collapse of microscopic biomass charcoal, resulting in uneven local impregnation.
In some embodiments of the present invention, the biomass charcoal in the biomass charcoal composite adsorption further comprises a surface stripping step before the impregnation step, for increasing the ratio of the surface functional groups.
In some embodiments of the present invention, the spherical honeycomb metal material is MOFs and tetraethylenepentamine, and the tetraethylenepentamine is loaded on the exposed surface of the honeycomb structure of the MOFs according to a mass ratio of 1.
In some embodiments of the present invention, the adsorption step of the spherical honeycomb type metal material is followed by a carbon dioxide concentration monitoring step: setting the lower limit of the concentration of the carbon dioxide tail gas as T, and the upper limit of water vapor in the gas after the biomass carbon composite material is adsorbed as M, wherein M is not more than 4%; and when the concentration of the carbon dioxide in the tail gas is less than T, regulating and controlling to reduce M, but controlling the ratio of M/T to be not less than a set value N.
It is understood that, in some embodiments, intelligent control is performed, the most basic goal is to reach the carbon dioxide concentration in the tail gas, such as 70% or 75%, and different lower limits are designed according to different requirements, but should be guaranteed not to fall below the set lower limit, once the carbon dioxide concentration is below the set lower limit, the reason is that the adsorption effect of the last adsorption process is not good, and the possible reason is that the adsorption time is too short, and the water vapor concentration content in the inlet gas is too large, generally speaking, after the adsorption time is set empirically, the water vapor content in the inlet gas is generally considered to be too large, and then the humidity is reduced, so that the inlet gas amount can be reduced or the adsorption time can be prolonged by adjusting the adsorption parameters of the front-end biomass carbon, but it should be understood that the ratio of M/T is controlled not to be less than the set value N, because the adsorption selectivity of the biomass carbon or biomass carbon composite is poor, and the main role is to reduce the water vapor content on the basis of preliminary adsorption, and if the ratio is too small, the adsorption effect of the spherical metal will be reduced, and the adsorption cost is increased.
The method reduces the content of the water vapor in the gas by adopting the biomass carbon adsorption, further can naturally reduce the water vapor content of the gas entering the spherical honeycomb metal material in the combined adsorption, further does not need to set a step of drying the gas, reduces the adsorption cost, and further reduces the gas adsorption cost as much as possible on the premise of meeting the gas emission purity by controlling the ratio of the carbon dioxide content in the final gas to the water vapor content in the intermediate step.
In some embodiments, the adsorbent is recycled and the desorption process after adsorption is achieved by varying the temperature, humidity and pressure.
In some embodiments, pressurization is required in the capture process, but in order to further save cost, the pressure difference between the upstream pipe network and the downstream pipe network of the natural gas pipe network is adopted for assisting pressurization, so that the problem of the pressure difference of the natural gas pipe network is solved, and the cost for increasing the pressure in the carbon dioxide capture process is reduced.
In other embodiments of the present invention, the cost of the combined adsorption can be further reduced, because the three adsorption processes are divided into three steps in the previous embodiment, such adsorption occupies a large space, in this embodiment, the adsorption material is set to be a core-shell structure, the biomass charcoal or biomass charcoal composite is roll-bonded to the exterior of the spherical honeycomb metal adsorption material, or the biomass charcoal composite is roll-bonded to the biomass charcoal, the gas is adsorbed by the outer shell and then reaches the internal adsorption, in the desorption process, the gas desorbed first has low purity and then enters the system for repeated capture, and the carbon dioxide desorbed can be collected after the concentration of the carbon dioxide reaches the standard.
Preparation of biomass charcoal composite adsorbent material in some embodiments:
washing 100g of corn stalk (or mixture of corn stalk and corncob), drying, vacuum carbonizing at 580 deg.C, pulverizing, and sieving to obtain 250 mesh powder; then placing the mixture in an ultrasonic oscillator for ultrasonic radiation for 15 minutes at the ultrasonic frequency of 25KHz, and performing suction filtration and drying; heating, refluxing and modifying in 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride solution with the concentration of 1.5mol/L at 100 ℃, filtering, and drying for 10 hours at 100 ℃ to obtain the biomass charcoal.
The mass ratio of the corn stalk biochar to the 1-aminoethyl-3-methylimidazole bromide to the polyacrylamide is 10.
The parameters of some of the raw materials used in the present invention are shown in table 1:
TABLE 1
| Type of parameter | Numerical value |
| Bulk density kg/m of biomass charcoal 3 | 642.5-669.1 |
| Spherical honeycomb typeMetal particle size (mm) | 2.2-2.4 |
| Initial inlet flow rate (L/min) | 60-90 |
| Maximum adsorption pressure (kpa) | 100 |
| Minimum analytic pressure (kpa) | 2.2 |
| Analysis temperature (. Degree. C.) | 150-180 |
Adopt the method of this application can make concentration behind the meeting of carbon dioxide than exclusive use physical adsorption concentration and go out a lot, and compare and exclusive use metal frame adsorption material adsorption cost greatly reduced, the reason is, this application does not have the step of exclusive use dry gas, but has reduced the vapor content who gets into the gas of metal ball adsorption in the adsorption process, and whether up to standard of its content can be through control and automated control to through the final concentration feedback regulation of carbon dioxide. Full automation is achieved. But also reduces the cost.
Example 1
A carbon dioxide combined capturing method comprises biomass carbon adsorption, biological carbon composite material adsorption and spherical honeycomb type metal material adsorption; a gas humidity monitoring step is also arranged between the biomass carbon composite material adsorption step and the spherical honeycomb type metal material adsorption step, and the mass percentage of water vapor in the gas entering the spherical honeycomb type metal material adsorption step after the gas is adsorbed by the biomass carbon composite material is less than 4%; the high-concentration carbon dioxide desorbed by the biological charcoal adsorption and biomass charcoal composite material is subjected to the next adsorption step, the high-concentration carbon dioxide gas desorbed by the spherical honeycomb metal material adsorption step is recovered, and the tail gas desorbed by the biomass charcoal adsorption, the biological charcoal composite material adsorption and the spherical honeycomb metal material adsorption step is subjected to the biomass charcoal adsorption again; the biomass charcoal adopted by the biomass charcoal composite material for adsorption is treated by the following steps: crushing corn straw biochar, and then sequentially soaking 1-aminoethyl-3-methylimidazole bromine salt solution and polyacrylamide; wherein the mass ratio of the corn stalk biochar to the 1-aminoethyl-3-methylimidazole bromine salt to the polyacrylamide is 10.
The parameters of the starting material in example 1 are shown in table 2:
| type of parameter | Numerical value |
| Bulk density kg/m of biomass charcoal 3 | 642.5 |
| Spherical honeycomb type metal material particle diameter (mm) | 2.2 |
| Initial inlet flow rate (L/min) | 60 |
| Maximum adsorption pressure (kpa) | 100 |
| Minimum analytic pressure (kpa) | 2.2 |
| Analysis temperature (. Degree.C.) | 150 |
Example 2 to example 6
Examples 2-6 differ from example 1 in the feed parameters. The parameters of examples 2-6 are shown in Table 3:
TABLE 3
Comparative example 1
And biomass charcoal is adopted for adsorption.
Comparative example 2
Adopts biochar composite material for adsorption.
Comparative example 3
Adopting spherical honeycomb type metal material for adsorption.
Comparative examples 1-3 the same flue gas samples were adsorbed as in examples 1-6, and the results are shown in table 4 for the following:
TABLE 4
As can be seen from the table above, the adsorption capacity in the embodiment of the present application is far greater than that of the three technologies used alone, and meanwhile, the cost of the three technologies used alone is 2-3 times that of the embodiment of the present application.
It should be noted that the above embodiments can be freely combined as necessary. The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (2)
1. A carbon dioxide combined capturing method is characterized by comprising biomass carbon adsorption, biomass carbon composite material adsorption and spherical honeycomb type metal material adsorption; a gas humidity monitoring step is also arranged between the biomass carbon composite material adsorption step and the spherical honeycomb type metal material adsorption step, and the mass percentage of water vapor in the gas entering the spherical honeycomb type metal material adsorption step after the biomass carbon composite material adsorption is less than 4%; the high-concentration carbon dioxide analyzed by the biological carbon adsorption and biomass carbon composite material adsorption enters the next adsorption step, the high-concentration carbon dioxide gas analyzed by the spherical honeycomb type metal material adsorption step is recovered, and the tail gas in the biomass carbon adsorption, biomass carbon composite material adsorption and spherical honeycomb type metal material adsorption steps enters the biomass carbon adsorption again;
the biomass charcoal adopted by the biomass charcoal composite material for adsorption is treated by the following steps: crushing corn straw biochar, and then sequentially soaking 1-aminoethyl-3-methylimidazole bromine salt solution and polyacrylamide; wherein the mass ratio of the corn stalk biochar to the 1-aminoethyl-3-methylimidazole bromine salt to the polyacrylamide is 10;
the biomass charcoal in the biomass charcoal composite material adsorption also has a surface stripping step before the dipping step, and is used for improving the proportion of surface functional groups;
the spherical honeycomb type metal material is prepared by loading tetraethylenepentamine on the exposed surface of a honeycomb structure of MOFs according to the mass ratio of 1.
2. The combined capturing method for carbon dioxide as claimed in claim 1, wherein the adsorption step of the spherical honeycomb type metal material is followed by a carbon dioxide concentration monitoring step: setting the lower limit of the concentration of carbon dioxide tail gas as T, and the upper limit of water vapor in the gas after the biomass carbon composite material is adsorbed as M, wherein M is not more than 4%; and when the concentration of the carbon dioxide in the tail gas is less than T, regulating and controlling to reduce M, but controlling the ratio of M/T to be not less than a set value N.
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| CN110548488A (en) * | 2019-09-04 | 2019-12-10 | 华中科技大学 | biochar-based nitrogen-rich composite material, and preparation and application thereof |
| CN113663649A (en) * | 2021-08-05 | 2021-11-19 | 华东师范大学 | Application of MOF (Metal organic framework) molding material in low-temperature carbon dioxide capture |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP6408082B1 (en) * | 2017-07-11 | 2018-10-17 | 株式会社西部技研 | Gas recovery concentrator |
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Patent Citations (7)
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| CN101370564A (en) * | 2005-08-08 | 2009-02-18 | 琳德股份有限公司 | System and method for purifying a gas |
| CN104619402A (en) * | 2012-09-28 | 2015-05-13 | 富士胶片株式会社 | Complex for carbon dioxide separation, module for carbon dioxide separation, method for producing complex for carbon dioxide separation |
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| CN113663649A (en) * | 2021-08-05 | 2021-11-19 | 华东师范大学 | Application of MOF (Metal organic framework) molding material in low-temperature carbon dioxide capture |
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