Acid gas adsorption device

Abstract

The invention provides an acid gas adsorption device capable of partially replacing a degraded acid gas adsorption part and reducing operation cost. An acid gas adsorption device according to an embodiment of the present invention is provided with: an acid gas adsorption unit through which a fluid can pass in a predetermined direction; and a single case. The acid gas adsorption part contains an acid gas adsorption material capable of adsorbing an acid gas. The acid gas adsorption part is divided into at least: a first adsorption part including an upstream end surface in the direction in which the fluid passes; and a second adsorption unit disposed on the downstream side of the first adsorption unit in the direction in which the fluid passes. The housing accommodates the first adsorption part and the second adsorption part together. The first adsorption part and / or the second adsorption part are / is divided into a plurality of parts in a direction intersecting the direction in which the fluid passes.

Description

Technical Field

[0001] The invention relates to an acid gas adsorption device. Background Art

[0002] In recent years, efforts have been made to separate and recover acidic gases contained in the atmosphere in order to reduce the environmental load. As such acidic gases, carbon dioxide (hereinafter sometimes referred to as CO2) that causes global warming can be mainly cited. As a representative example of the above efforts, the carbon dioxide capture, utilization and storage (CCUS) cycle is known. As a carbon dioxide adsorption device used in such separation and recovery of carbon dioxide, a gas separation unit having a carbon dioxide adsorption part with a granular structure has been proposed (for example, see Patent Document 1). In such a carbon dioxide adsorption device, a fluid containing CO2 is supplied, so that the carbon dioxide adsorbent adsorbs CO2 from the fluid and releases the adsorbed CO2 under specified conditions. However, the fluid supplied to the carbon dioxide adsorption device sometimes contains poisoning and deterioration components that deteriorate the carbon dioxide adsorbent. If the adsorption and release of CO2 are repeatedly performed in the carbon dioxide adsorption device, the activity of the carbon dioxide adsorbent may be reduced due to the poisoning and deterioration components. In this case, it is necessary to stop the operation of the carbon dioxide adsorption device and replace the entire CO2 adsorption part, which has the problem of complicated replacement work and increased operating costs.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: International Publication No. 2014 / 170184 Summary of the invention

[0006] A main object of the present invention is to provide an acid gas adsorption device capable of partially replacing a deteriorated acid gas adsorption unit and reducing running costs.

[0007] [1] An acid gas adsorption device according to an embodiment of the present invention includes an acid gas adsorption section through which a fluid can pass in a predetermined direction. The acid gas adsorption section includes an acid gas adsorption material capable of adsorbing acid gas. The acid gas adsorption section is divided into at least: a first adsorption section including an upstream end surface in the direction in which the fluid passes; and a second adsorption section located on the downstream side of the first adsorption section in the direction in which the fluid passes.

[0008] [2] In the acid gas adsorption device described in [1] above, the acid gas may be carbon dioxide.

[0009] [3] In the acid gas adsorption device described in [1] or [2] above, the size of the second adsorption part in the passing direction of the fluid may be substantially the same as the size of the first adsorption part.

[0010] [4] In the acid gas adsorption device described in any one of [1] to [3] above, the first adsorption section and / or the second adsorption section may be divided into a plurality of parts in a direction intersecting (preferably orthogonal to) the passing direction of the fluid.

[0011] [5] The acid gas adsorption device described in any one of [1] to [4] may further include a housing. The housing may accommodate the first adsorption unit and the second adsorption unit together.

[0012] Effects of the Invention

[0013] According to the embodiment of the present invention, it is possible to realize an acid gas adsorption device capable of partially replacing a deteriorated acid gas adsorption unit and reducing running costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic configuration diagram of an acid gas adsorption device according to one embodiment of the present invention.

[0015] Figure 2 This is a schematic configuration diagram of an acid gas adsorption device according to another embodiment of the present invention.

[0016] Figure 3 This is a schematic configuration diagram of an acid gas adsorption device according to still another embodiment of the present invention.

[0017] Figure 4 yes Figure 3 A schematic diagram of an implementation of the first block in FIG.

[0018] Figure 5 yes Figure 3 A schematic three-dimensional diagram of the first block in FIG.

[0019] Figure 6 yes Figure 5 Central cross-section of the first block in FIG.

[0020] Figure 7 Is used to illustrate the Figure 3 A schematic diagram illustrating a process of removing the first adsorption section from the acid gas adsorption device.

[0021] Figure 8 It is used to illustrate Figure 7 A schematic diagram illustrating the process of adding a new adsorption section to the acid gas adsorption device in FIG. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited to these embodiments. In addition, in order to explain more clearly, the accompanying drawings sometimes schematically show the width, thickness, shape, etc. of each part compared with the embodiments, but this is only an example and does not limit the interpretation of the present invention.

[0023] A. Overview of Acid Gas Adsorption Device

[0024] Figure 1 This is a schematic configuration diagram of an acid gas adsorption device according to one embodiment of the present invention.

[0025] The acid gas adsorption device 100 shown in the figure includes an acid gas adsorption section 1 through which a fluid can pass in a predetermined direction. The acid gas adsorption section 1 includes an acid gas adsorption material capable of adsorbing acid gas. The acid gas adsorption section 1 is divided into at least a first adsorption section 11 and a second adsorption section 12. The first adsorption section 11 includes an upstream end surface 1a of the acid gas adsorption section 1 in the passing direction of the fluid. The second adsorption section 12 is arranged on the downstream side of the first adsorption section 11 in the passing direction of the fluid. Typically, the second adsorption section 12 is adjacent to the first adsorption section 11.

[0026] The fluid supplied to the acid gas adsorption device sometimes contains poisoning and deteriorating components that deteriorate the acid gas adsorption material. Since the fluid passes through the first adsorption part and the second adsorption part in sequence, the poisoning and deteriorating components contained in the fluid are relatively easy to adhere to the first adsorption part, and the acid gas adsorption material contained in the first adsorption part is easy to deteriorate compared with the acid gas adsorption material contained in the second adsorption part. Therefore, the life of the first adsorption part is shorter than that of the second adsorption part. According to one embodiment of the present invention, since the first adsorption part with a relatively short life and the second adsorption part with a relatively long life are divided, the first adsorption part and the second adsorption part can be replaced separately according to the life. Therefore, compared with the case where the acid gas adsorption part is replaced as a whole, the acid gas adsorption part can be replaced partly and smoothly. As a result, the time required for replacing the acid gas adsorption part can be reduced, so the operation stop time of the acid gas adsorption device can be shortened. In addition, since the first adsorption part and the second adsorption part can be replaced at an appropriate time corresponding to the life, the running cost (specifically, the preparation cost of the new adsorption part and the disposal cost of the adsorption part after use) can be reduced.

[0027] Regarding the acidic gas that is the adsorption object of the acidic gas adsorption device, for example, carbon dioxide (CO2), hydrogen sulfide, sulfur dioxide, nitrogen dioxide, dimethyl sulfide (DMS), hydrogen chloride, etc. can be cited. In one embodiment, the acidic gas is carbon dioxide (CO2), and the fluid is a CO2-containing gas. The CO2-containing gas contains nitrogen in addition to CO2. The CO2-containing gas is representatively air (atmosphere). The CO2 concentration in the CO2-containing gas before being supplied to the acidic gas adsorption device is, for example, 100 ppm (volume basis) or more and 2 volume % or less.

[0028] Hereinafter, a case where the acid gas is carbon dioxide (CO 2 ) will be described in detail.

[0029] When the acid gas is CO 2 , the acid gas adsorbent is a carbon dioxide adsorbent.

[0030] As the carbon dioxide adsorbent, any appropriate compound that can adsorb and desorb CO2 can be used. Examples of the carbon dioxide adsorbent include: nitrogen-containing compounds; ionic liquids; deep eutectic solvents; alkaline compounds such as sodium hydroxide and potassium hydroxide; carbonates such as calcium carbonate and potassium carbonate; and bicarbonates such as calcium bicarbonate and potassium bicarbonate.

[0031] In one embodiment, the carbon dioxide adsorbent comprises a nitrogen-containing compound.

[0032] More specifically, the nitrogen-containing compound includes: primary amines such as monoethanolamine and polyethyleneamine; secondary amines such as diethanolamine, cyclic amines, and N-(3-aminopropyl)diethanolamine; tertiary amines such as methyldiethylamine and triethanolamine; ethyleneamine compounds such as tetraethylenepentamine; aminosilane coupling agents such as aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane, and polyethyleneimine-trimethoxysilane; organic monomers having primary to tertiary amino groups such as ethyleneimine and styrene to which an amino group is imparted; organic polymers having primary to tertiary amino groups such as linear polyethyleneimine, branched polyethyleneimine having primary to tertiary amino groups, polyamideamine, and polyethyleneamine; substituted piperazine compounds such as 1-(2-hydroxyethyl)piperazine; and organic / inorganic compounds to which an amino group is imparted as a substituent.

[0033] Among the carbon dioxide adsorbents, preferably there are methyldiethylamine, monoethanolamine, cyclic amines, diethanolamine, tetraethylenepentamine, ethyleneimine, linear polyethyleneimine, branched polyethyleneimine, and organic / inorganic compounds having an amino group as a substituent.

[0034] Carbon dioxide adsorbing materials like these can be used alone or in combination.

[0035] The first adsorption unit 11 and the second adsorption unit 12 may contain the same acidic gas adsorbent among the above-mentioned acidic gas adsorbents (carbon dioxide adsorbents), or may contain different acidic gas adsorbents. In one embodiment, the first adsorption unit 11 and the second adsorption unit 12 contain the same acidic gas adsorbent.

[0036] In one embodiment, the first adsorption unit 11 is hydrophobic. The fluid supplied to the acid gas adsorption device may contain droplets such as rain. In addition, if the adsorption and desorption of acid gas are repeated in the acid gas adsorption device, dew may form on the upstream side of the acid gas adsorption unit. When such water penetrates into the acid gas adsorption unit along with the fluid, the acid gas adsorption performance of the acid gas adsorption device may be reduced due to the dissolution of the acid gas adsorption material and / or the dilution of the acid gas adsorption material.

[0037] On the other hand, in one embodiment, since the first adsorption part including the upstream end surface has hydrophobicity, it is possible to suppress water from entering the acid gas adsorption part. Therefore, it is possible to stably maintain excellent acid gas adsorption performance.

[0038] Typically, the first adsorption unit 11 includes a hydrophobic acidic gas adsorbent (hereinafter referred to as a hydrophobic adsorbent).

[0039] The hydrophobic adsorbent is substantially insoluble in water. Typically, the hydrophobic adsorbent is in a liquid state at normal temperature and pressure (23° C., 0.1 MPa).

[0040] The solubility of the hydrophobic adsorbent in water is, for example, 1.0 g / 100 g-H2O or less, preferably 0.8 g / 100 g-H2O or less. It should be noted that the lower limit of the solubility of the hydrophobic adsorbent in water is typically 0.01 g / 100 g-H2O. If the solubility of the hydrophobic adsorbent in water is in such a range, excellent hydrophobicity can be stably imparted to the first adsorption part. The solubility in water is measured by, for example, immersing the object in water at 25°C for 3 hours and causing the mass change of the dissolved object.

[0041] The Hildebrand solubility parameter of a hydrophobic adsorbent material at 25° C. is, for example, 7.0 (cal / cm 3 ) 1 / 2 ~11.0(cal / cm 3 ) 1 / 2 , preferably 8.8 (cal / cm 3 ) 1 / 2 ~10.0(cal / cm 3 ) 1 / 2For example, the Hildebrand solubility parameter can be calculated by the Fedors method described in "Polymer Engineering and Science, February, 1974, Vol. 14 No. 2 Page 147-154" based on information obtained from functional groups detected by structural analysis using infrared spectroscopy, Raman spectroscopy, etc., and by using the Hildebrand method.

[0042] It should be noted that the hydrophobic adsorbent contained in the first adsorption part is determined by, for example, structural analysis such as infrared spectroscopy and Raman spectroscopy; mass analysis such as gas chromatography and liquid chromatography; elemental analysis such as CHN elemental analysis and electron beam microanalyzer (EPMA). When the first adsorption part contains a plurality of hydrophobic adsorbents, the Hildebrand solubility parameter (hereinafter sometimes referred to as SP value) of the hydrophobic adsorbent contained in the first adsorption part is calculated as the total value of the product of the volume ratio of each hydrophobic adsorbent and the SP value.

[0043] More specifically, first, a cylindrical sample is obtained from a portion of the first adsorption unit containing a hydrophobic adsorbent (representatively, an acidic gas adsorbent layer described later, a granular adsorbent described later), and then, an element mapping image of the following nine positions in the sample is obtained at a magnification of 300 times using an electron beam microanalyzer (EPMA) capable of detecting light elements such as nitrogen.

[0044] The first position is the center of one end surface of the sample, the second position is the end of the one end surface, and the third position is the midpoint of the line segment connecting the first position and the second position.

[0045] The fourth position is the center of the cross section obtained by cutting the center of the sample in the longitudinal direction in a direction perpendicular to the longitudinal direction. The fifth position is the end of the cross section. The sixth position is the midpoint of the line segment connecting the fourth position and the fifth position.

[0046] The seventh position: the center of the other end surface of the sample, the eighth position: the end of the other end surface, and the ninth position: the midpoint of the line segment connecting the seventh position and the eighth position.

[0047] Next, the area ratios (element ratios) of the plurality of hydrophobic adsorbent materials are respectively obtained based on the element mapping images of the first position to the ninth position. Then, the average value of the plurality of area ratios (element ratios) obtained is calculated. Next, based on the average value of the area ratios (element ratios) of the plurality of hydrophobic adsorbent materials, the ratio (Vol%) of the volume of each hydrophobic adsorbent material relative to the total volume of the plurality of hydrophobic adsorbent materials (100 Vol%) is calculated.

[0048] Next, the product of the volume ratio of each hydrophobic adsorbent and the SP value is added. For example, when the first adsorption part includes the first hydrophobic adsorbent A (SP value 10, volume ratio 70 Vol%) and the second hydrophobic adsorbent B (SP value 8, volume ratio 30 Vol%), the SP value of the hydrophobic adsorbent included in the first adsorption part is calculated using the following formula (1) as 9.4 (cal / cm 3 ) 1 / 2 .

[0049] (10×70 / 100)+(8×30 / 100)=9.4···(1)

[0050] As the hydrophobic adsorbent, for example, the hydrophobic material among the above-mentioned carbon dioxide adsorbent can be cited. As specific examples of the hydrophobic adsorbent, there can be cited: amine compounds having a hydrophobic group, ionic liquids, hydrophobic deep eutectic solvents, nitrogen-containing carbon. The hydrophobic adsorbent can be used alone or in combination.

[0051] Examples of the hydrophobic group possessed by the amine compound include alkyl groups such as methyl groups and aryl groups such as phenyl groups. Specific examples of the amine compound having a hydrophobic group include phenethylamine. The amine compound having a hydrophobic group may be used alone or in combination.

[0052] Ionic liquids are liquid "salts" consisting only of ions (anions and cations). Examples of cations of ionic liquids include: ammonium ions such as imidazolium salts and pyridinium salts, phosphonium ions, sulfonium salts, and inorganic ions. Examples of anions of ionic liquids include: halogen ions such as bromide ions and trifluoromethanesulfonates; boron ions such as tetraphenylborate; phosphorus ions such as hexafluorophosphate; and sulfur ions such as alkylsulfonates. Ionic liquids can be used alone or in combination.

[0053] As for the hydrophobic deep eutectic solvent, for example, carboxylic acid-containing organic compounds represented by decanoic acid, ester-containing organic substances represented by phenyl salicylate, alcohols represented by decanol, phenols represented by thymol, ketone-containing organic substances represented by camphor, ammonium salts having halogen or hydroxyl anions represented by tetra-n-octylammonium bromide, amine compound salts having halogen or hydroxyl anions represented by triethylenetetramine chloride, carboxylic acid-containing organic compounds represented by lauric acid, alcohols represented by menthol, and phenols represented by thymol as hydrogen bond acceptors (HBA) can be mentioned. The hydrophobic deep eutectic solvents can be used alone or in combination.

[0054] The first adsorption unit 11 having hydrophobicity may include particles having acidic gas adsorption capacity (hereinafter referred to as acidic gas adsorption capacity particles) and a hydrophobic binder instead of the hydrophobic adsorption material. In this way, appropriate hydrophobicity can be imparted to the first adsorption unit.

[0055] The acidic gas adsorbing particles are in a solid state at normal temperature and pressure (23°C, 0.1 MPaA (absolute pressure)). Typically, the first adsorbing unit 11 includes a plurality of acidic gas adsorbing particles. The acidic gas adsorbing particles contained in the first adsorbing unit 11 may be primary particles or secondary particles obtained by agglomerating a plurality of primary particles.

[0056] The acidic gas adsorbing particles may be composed only of an acidic gas adsorbing material that is solid at normal temperature and pressure, or may be composed of an acidic gas adsorbing material and a carrier.

[0057] Examples of the acidic gas adsorbent contained in the acidic gas adsorbent particles include the above-mentioned carbon dioxide adsorbent. The acidic gas adsorbent contained in the acidic gas adsorbent particles may be the above-mentioned hydrophobic adsorbent or a water-soluble hydrophilic adsorbent.

[0058] The solubility of the hydrophilic adsorbent in water is, for example, more than 1.0 g / 100 g-H2O, preferably 3.0 g / 100 g-H2O or more. The upper limit of the solubility of the hydrophilic adsorbent in water is typically 800 g / 100 g-H2O.

[0059] The Hildebrand solubility parameter (SP value) of the hydrophilic adsorbent material at 25° C. is, for example, 11.5 (cal / cm 3 ) 1 / 2 ~24.0(cal / cm 3 ) 1 / 2 , preferably 11.9 (cal / cm 3 ) 1 / 2 ~14.5(cal / cm 3 ) 1 / 2 In addition, when the first adsorption part includes a plurality of types of hydrophilic adsorption materials, the SP value of the hydrophilic adsorption material is calculated in the same manner as the SP value of the hydrophobic adsorption material described above.

[0060] The acidic gas adsorbing particles preferably contain a hydrophilic adsorbent material.

[0061] Typically, the acid gas adsorption capacity of a hydrophilic adsorbent is greater than that of a hydrophobic adsorbent. Therefore, if the acid gas adsorbent particle includes a hydrophilic adsorbent, the acid gas adsorption performance of the first adsorbent can be improved compared to the case where the acid gas adsorbent particle includes a hydrophobic adsorbent.

[0062] When the acid gas is CO2, the CO2 adsorption capacity of the acid gas adsorbent is evaluated in the form of the amount of CO2 that can be adsorbed per 1 kg of the acid gas adsorbent (when the acid gas adsorbent is supported on a carrier, the total of the acid gas adsorbent and the carrier is 1 kg) under the conditions of 25°C, 50% RH and CO2 partial pressure of 15 kPa.

[0063] The CO2 adsorption capacity of the hydrophilic adsorbent is, for example, 0.1 mol / kg-adsorbent or more, preferably 0.7 mol / kg-adsorbent or more, and more preferably 1.0 mol / kg-adsorbent or more. For example, the CO2 adsorption capacity can be measured by the method described in Document 3-2-1 of the Second 2015 Carbon Dioxide Recovery and Storage Field Evaluation Seminar (2).

[0064] It should be noted that the CO2 adsorption capacity of the hydrophobic adsorbent is, for example, less than 2.0 mol / kg-adsorbent, further, for example, less than 1.0 mol / kg-adsorbent, further, for example, less than 0.7 mol / kg-adsorbent, further, for example, less than 0.1 mol / kg-adsorbent.

[0065] Examples of the hydrophilic adsorbent include amine compounds having no hydrophobic group. Specific examples of the amine compounds having no hydrophobic group include linear polyethyleneimine and branched polyethyleneimine having primary to tertiary amino groups. The hydrophilic adsorbent may be used alone or in combination.

[0066] In the acid gas adsorption particles, the carrier carries the acid gas adsorption material. As the carrier, any appropriate material can be used. The carrier is preferably a porous carrier. If the carrier is a porous carrier, mesopores can be formed on the surface that can contact the acid gas. The porous carrier is described in detail below. In addition, from the perspective of thermal conductivity, metal materials are sometimes used as the carrier. For example, steel materials such as carbon steel and alloy steel; non-ferrous metals such as copper, aluminum, nickel and their alloys. In the case of metal materials, it is not limited to porous shapes.

[0067] Typically, the acidic gas adsorbing particles are formed by arbitrarily and appropriately combining the above-mentioned acidic gas adsorbing materials and the above-mentioned carriers. Specific examples of the acidic gas adsorbing particles include amine-supported polymers, amine-supported MOFs, and amine-supported nitrogen-doped carbons.

[0068] The mass ratio of the acidic gas adsorbent to the carrier (acidic gas adsorbent / carrier) is, for example, 0.1 to 5, or preferably 1 to 3.

[0069] The hydrophobic binder can bind the acidic gas adsorbing particles. The hydrophobic binder is typically an organic binder that is substantially insoluble in water.

[0070] The solubility of the hydrophobic binder in water is, for example, 1.0 g / 100 g-H2O or less, preferably 0.5 g / 100 g-H2O or less. It should be noted that the lower limit of the solubility of the hydrophobic binder in water is typically 0.01 g / 100 g-H2O. If the solubility of the hydrophobic binder in water is within such a range, excellent hydrophobicity can be imparted to the first adsorption part.

[0071] The Hildebrand solubility parameter (SP value) of the hydrophobic adhesive at 25° C. is, for example, 5.0 (cal / cm 3 ) 1 / 2 ~11.0(cal / cm 3 ) 1 / 2 , preferably 6.2 (cal / cm 3 ) 1 / 2 ~10.4(cal / cm 3 ) 1 / 2 In addition, when the first adsorption part contains a plurality of types of hydrophobic binders, the SP value of the hydrophobic binder is calculated in the same manner as the SP value of the hydrophobic adsorption material described above.

[0072] Examples of the hydrophobic binder include fluoropolymers such as polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), perfluoroethylene propylene copolymer (FEP), and ethylene tetrafluoroethylene copolymer (ETFE); and amorphous plastics such as polysulfone, polyvinylidene chloride, polyimide, polyvinyl chloride, and polyethersulfone (PES). The hydrophobic binder may be used alone or in combination.

[0073] As the hydrophobic binder, preferably a fluoropolymer is used, and more preferably polyvinylidene fluoride is used. If the hydrophobic binder contains a fluoropolymer (polyvinylidene fluoride), the hydrophobicity of the first adsorption part can be further improved.

[0074] The weight average molecular weight Mw (polystyrene equivalent) of the hydrophobic binder is, for example, 10,000 to 10,000,000, or preferably 200,000 to 1,000,000.

[0075] The content ratio of the hydrophobic binder is, for example, 0.01 to 5.0 parts by mass, or preferably 0.12 to 1.0 part by mass, based on 1 part by mass of the acidic gas adsorbing particles.

[0076] In one embodiment, the second adsorption unit 12 is configured to have a larger acid gas adsorption capacity than the first adsorption unit 11. Typically, the second adsorption unit 12 includes an acid gas adsorption material (hereinafter referred to as a large-capacity adsorption material) having a larger acid gas adsorption capacity than the above-mentioned hydrophobic adsorption material. If the second adsorption unit includes a large-capacity adsorption material, the acid gas can be stably adsorbed from the fluid in the second adsorption unit. Therefore, even if the first adsorption unit is hydrophobic, the adsorption performance of the entire acid gas adsorption device can be sufficiently ensured.

[0077] The CO 2 adsorption capacity of the large-capacity adsorbent is, for example, 1 mol / kg-adsorbent or more, preferably 3 mol / kg-adsorbent or more, and more preferably 5 mol / kg-adsorbent or more.

[0078] Examples of the large-capacity adsorbent include the above-mentioned hydrophilic adsorbents, and preferably include linear polyethyleneimine and branched polyethyleneimine.

[0079] In addition, the large-capacity adsorbent material may be supported on the above-mentioned carrier to form particles having an acidic gas adsorbing capacity. When the second adsorbent 12 includes particles having an acidic gas adsorbing capacity, the second adsorbent 12 preferably further includes a hydrophilic binder.

[0080] The hydrophilic binder can bind the acidic gas adsorbing particles. The hydrophilic binder is an organic binder that is substantially soluble in water.

[0081] The solubility of the hydrophilic binder in water is, for example, more than 5 g / 100 g-H2O, preferably 10 g / 100 g-H2O or more. The upper limit of the solubility of the hydrophilic binder in water is typically 80 g / 100 g-H2O.

[0082] The Hildebrand solubility parameter (SP value) of the hydrophilic adhesive at 25° C. is, for example, 11.5 (cal / cm 3 ) 1 / 2 ~24.0(cal / cm 3 ) 1 / 2 , preferably 11.9 (cal / cm 3 )1 / 2 ~14.5(cal / cm 3 ) 1 / 2 It should be noted that, when the second adsorption part contains a plurality of hydrophilic binders, the SP value of the hydrophilic binder is calculated in the same manner as the SP value of the hydrophobic adsorption material described above, except that a sample is obtained from a portion of the second adsorption part containing the hydrophilic binder (representatively, the acidic gas adsorption material layer described later, the granular adsorption material described later).

[0083] As the hydrophilic binder, for example, water-soluble polymers such as (meth) acrylic resin, amylose, methyl cellulose, and polyvinyl alcohol can be cited, and methyl cellulose can be preferably cited. It should be noted that in this specification, the so-called "(meth) acrylic resin" includes acrylic resin and methacrylic resin. The hydrophilic binder can be used alone or in combination.

[0084] The weight average molecular weight Mw (polystyrene equivalent) of the hydrophilic binder is, for example, 10,000 to 10,000,000, or preferably 200,000 to 1,000,000.

[0085] The content ratio of the hydrophilic binder is, for example, 0.01 to 5.0 parts by mass, or preferably 0.12 to 1.0 part by mass, based on 1 part by mass of the acidic gas adsorbing particles.

[0086] In one embodiment, an acid gas adsorption device 100 includes: an acid gas adsorption unit 1 including a first adsorption unit 11 and a second adsorption unit 12; and a housing 2. The housing 2 accommodates the acid gas adsorption unit 1. In other words, the housing 2 accommodates the first adsorption unit 11 and the second adsorption unit 12 together. If the housing accommodates the first adsorption unit and the second adsorption unit together, the acid gas adsorption device can be miniaturized compared to a case where the first adsorption unit and the second adsorption unit are accommodated in different housings, so the equipment cost can be suppressed to be relatively low, and the amount of acid gas recovered per unit area can be increased.

[0087] In the example shown in the figure, the housing 2 has a cylindrical shape extending in the direction of passage of the fluid. That is, the direction of passage of the fluid is roughly parallel to the axial direction of the housing 2. The upstream end of the housing 2 in the direction of passage of the fluid is configured as a first opening 21. The downstream end of the housing 2 in the direction of passage of the fluid is configured as a second opening 22. The acid gas adsorption unit 1 is arranged between the first opening 21 and the second opening 22 in the internal space of the housing 2. The first adsorption unit 11 is arranged between the first opening 21 and the second adsorption unit 12. The second adsorption unit 12 is arranged on the opposite side of the first opening 21 relative to the first adsorption unit 11. The first opening 21 and the second opening 22 can each allow fluid to pass through.

[0088] The dimension L of the acid gas adsorption unit 1 in the direction in which the fluid passes is not particularly limited as long as the pressure loss does not increase the fan driving power, and is, for example, 0.5 m or more, preferably 0.6 m or more, and, for example, 2.0 m or less, preferably 1.0 m or less. The dimension L of the acid gas adsorption unit 1 in the direction perpendicular to the direction in which the fluid passes is not particularly limited, and is, for example, 1.5 m or more, preferably 2.0 m or more, and, for example, 4.0 m or less, preferably 3.0 m or less.

[0089] The first adsorption unit 11 includes an upstream end surface 1a of the acid gas adsorption unit 1 in the passing direction of the fluid. The second adsorption unit 12 in the illustrated example includes a downstream end surface 1b of the acid gas adsorption unit 1 in the passing direction of the fluid. Typically, the passing direction of the fluid is orthogonal to the upstream end surface 1a and the downstream end surface 1b of the acid gas adsorption unit 1.

[0090] The dimensions of the first adsorption part 11 and the second adsorption part 12 in the passing direction of the fluid can be any appropriate value depending on the acid gas adsorption material used. In one embodiment, in the passing direction of the fluid, the dimension L1 of the first adsorption part 11 is, for example, 5% or more, preferably 10% or more, and for example, 50% or less, preferably 35% or less, relative to the total length L of the acid gas adsorption part 1.

[0091] If the size of the first adsorption part is equal to or larger than the lower limit, the second adsorption part arranged adjacent to the first adsorption part can be stably suppressed from being degraded by the poisoning and degrading components. If the size of the first adsorption part is equal to or smaller than the upper limit, the running cost can be further reduced.

[0092] A gap may be formed between the first adsorption part 11 and the second adsorption part 12 in the passing direction of the fluid. Generally, in the acidic gas adsorption part, the fluid tends to flow near the center and is not easy to flow in the outer part. In this regard, if a gap is formed between the first adsorption part and the second adsorption part, the flow deviation of the fluid in the acidic gas adsorption part can be reduced. In the passing direction of the fluid, the size of the gap is, for example, 30% or less, preferably 10% or less, relative to the total length L of the acidic gas adsorption part in the passing direction of the fluid (the sum of the size of the first adsorption part and the size of the second adsorption part in the passing direction of the fluid). If the size of the gap is below the above upper limit, it is possible to suppress the fluid from being retained between the first adsorption part and the second adsorption part, thereby allowing the fluid to flow smoothly from the first adsorption part to the second adsorption part.

[0093] like Figure 2As shown, in one embodiment, the acid gas adsorption unit 1 includes an n-th adsorption unit 13 in addition to the first adsorption unit 11 and the second adsorption unit 12. n is, for example, 3 or more and 30 or less. Typically, the n-th adsorption unit 13 is accommodated in one housing 2 together with the first adsorption unit 11 and the second adsorption unit 12. In the example shown in the figure, the acid gas adsorption unit 1 includes a third adsorption unit 133, a fourth adsorption unit 134, and a fifth adsorption unit 135 in addition to the first adsorption unit 11 and the second adsorption unit 12. In other words, the acid gas adsorption unit 1 is divided into n parts in the passing direction of the fluid. The third adsorption unit to the n-th adsorption unit are sequentially arranged on the downstream side of the second adsorption unit in the passing direction of the fluid. The n-th adsorption unit 13 may include the same acid gas adsorption material as the second adsorption unit 12, or may include an acid gas adsorption material different from the second adsorption unit 12. The n-th adsorption unit 13 located on the most downstream side in the passing direction of the fluid among the n-th adsorption units 13 includes the downstream end surface 1b of the acid gas adsorption unit 1. The first adsorption unit 11 , the second adsorption unit 12 , and the nth adsorption unit 13 preferably contain the same acidic gas adsorbent.

[0094] A gap may be formed between adjacent adsorption parts among the second to nth adsorption parts in the passing direction of the fluid. The size range of the gap is the same as the size range of the gap between the first adsorption part 11 and the second adsorption part 12 described above.

[0095] In one embodiment, the size of the second adsorption portion in the passing direction of the fluid is substantially the same as the size L1 of the first adsorption portion 11. According to such a structure, as described in detail below, when the first adsorption portion with a relatively short life is replaced, the second adsorption portion with a relatively long life can be used as the next first adsorption portion. It should be noted that in the present application specification, the so-called substantially the same size includes a situation where the difference between their sizes is within 10 cm. In addition, the size of the nth adsorption portion in the passing direction of the fluid is preferably substantially the same as the size L1 of the first adsorption portion 11.

[0096] like Figure 3 As shown, the first adsorption part 11 can be divided into a plurality of first blocks 11a in a direction intersecting the passing direction of the fluid (preferably an orthogonal direction). In other words, the first adsorption part 11 is composed of a plurality of first blocks 11a arranged side by side in a direction intersecting the passing direction of the fluid (preferably an orthogonal direction). Thus, a relatively small first block can be manufactured to form the first adsorption part. Therefore, compared with the case where the first adsorption part is manufactured together, the first adsorption part can be easily manufactured. In addition, the part (first block) in the first adsorption part 11 that is particularly prone to deterioration can be replaced separately.

[0097] The size of the first block 11a in the direction of fluid passage is, for example, 0.10 m or more, preferably 0.15 m or more, and, for example, 0.30 m or less, preferably 0.20 m or less. The size of the first block 11a in the direction orthogonal to the direction of fluid passage is, for example, 0.10 m or more, preferably 0.15 m or more, and, for example, 0.80 m or less, preferably 0.60 m or less.

[0098] When the first adsorption unit 11 is composed of a plurality of first blocks 11 a , the plurality of first blocks 11 a may be configured as a cartridge that can be collectively replaced.

[0099] The mutually adjacent first blocks 11 a among the plurality of first blocks 11 a may have a gap formed therebetween, or may be in contact with each other in a direction intersecting (preferably, orthogonal to) the direction in which the fluid passes.

[0100] In the example shown in the figure, the first adsorption portion 11 is divided into four in the direction intersecting the passing direction of the fluid (preferably the orthogonal direction, the up-down direction of the paper). The number of divisions of the first adsorption portion in the direction intersecting the passing direction of the fluid (preferably the orthogonal direction) is not limited to this. In addition, the first adsorption portion 11 may also be divided into multiple parts in the direction intersecting the passing direction of the fluid (preferably the orthogonal direction, the depth direction of the paper). The number of divisions of the first adsorption portion in the direction intersecting the passing direction of the fluid (preferably the orthogonal direction) is, for example, greater than 2 and less than 300.

[0101] The plurality of first blocks 11 a may include the same acid gas adsorbing material or different acid gas adsorbing materials.

[0102] In one embodiment, the second adsorption part 12 is divided into a plurality of second blocks 12a in a direction intersecting the passing direction of the fluid (preferably an orthogonal direction). The second adsorption part 12 is composed of a plurality of second blocks 12a arranged side by side in a direction intersecting the passing direction of the fluid (preferably an orthogonal direction). Thus, a relatively small second block can be manufactured to constitute the second adsorption part, so that the second adsorption part can be easily manufactured. In addition, the part (second block) that is easily deteriorated in the second adsorption part can be replaced separately.

[0103] The size range of the second block 12a is the same as the size range of the first block 11a described above.

[0104] When the second adsorption unit 12 is composed of a plurality of second blocks 12 a , the plurality of second blocks 12 a may be configured as a cartridge that can be replaced collectively.

[0105] The second blocks 12a adjacent to each other among the plurality of second blocks 12a may have a gap formed therebetween, or may be in contact with each other in a direction intersecting (preferably, orthogonal to) the direction in which the fluid passes.

[0106] In the example shown in the figure, the second adsorption portion 12 is divided into four in the direction intersecting the passage direction of the fluid (preferably the orthogonal direction, the up-down direction of the paper). The number of divisions of the second adsorption portion in the direction intersecting the passage direction of the fluid (preferably the orthogonal direction) is not limited to this. In addition, the second adsorption portion 12 may also be divided into multiple parts in the direction intersecting the passage direction of the fluid (preferably the orthogonal direction, the depth direction of the paper). The number of divisions of the second adsorption portion in the direction intersecting the passage direction of the fluid (preferably the orthogonal direction) is, for example, greater than 2 and less than 300, and is preferably the same as the number of divisions of the first adsorption portion.

[0107] The plurality of second blocks 12 a may include the same acid gas adsorbing material or different acid gas adsorbing materials.

[0108] In one embodiment, the nth adsorption unit 13 is divided into a plurality of nth blocks 13a in a direction intersecting the passing direction of the fluid (preferably an orthogonal direction). The nth adsorption unit 13 is composed of a plurality of nth blocks 13a arranged side by side in a direction intersecting the passing direction of the fluid (preferably an orthogonal direction). Thus, a relatively small nth block can be manufactured to constitute the nth adsorption unit, so that the nth adsorption unit can be easily manufactured.

[0109] The size range of the nth block 13 a is the same as the size range of the first block 11 a described above.

[0110] The mutually adjacent n-th blocks 13 a among the plurality of n-th blocks may have a gap formed therebetween, or may be in contact with each other in a direction intersecting (preferably, orthogonal to) the direction in which the fluid passes.

[0111] In the example shown in the figure, the nth adsorption portion 13 is divided into four in the direction intersecting the passing direction of the fluid (preferably the orthogonal direction, the up-down direction of the paper). The number of divisions of the nth adsorption portion in the direction intersecting the passing direction of the fluid (preferably the orthogonal direction) is not limited to this. In addition, the nth adsorption portion 13 can be divided into multiple parts in the direction intersecting the passing direction of the fluid (preferably the orthogonal direction, the depth direction of the paper). The number of divisions of the nth adsorption portion in the direction intersecting the passing direction of the fluid (preferably the orthogonal direction) is, for example, greater than 2 and less than 300, and is preferably the same as the number of divisions of the first adsorption portion.

[0112] The plurality of n-th blocks 13 a may include the same acid gas adsorbing material or different acid gas adsorbing materials.

[0113] Hereinafter, the specific structure of the acid gas adsorption unit will be described.

[0114] B. Acid gas adsorption unit

[0115] As described above, the acid gas adsorption unit 1 includes the first adsorption unit 11 and the second adsorption unit 12. In addition, the acid gas adsorption unit 1 may further include an nth adsorption unit. Typically, the first to nth adsorption units have the same structure except for the difference in size. Figure 1 The first adsorption portion 11 (integrally formed) and Figure 3 The first block 11a shown has the same structure except for the different size. Figure 3 The structure of the first block 11a shown will be described in detail.

[0116] In one embodiment, if Figure 4 As shown, the first block 11 a includes a plurality of adsorption material layers 71 .

[0117] The plurality of adsorbent layers 71 are stacked with a gap in the thickness direction thereof. In the example shown in the figure, five adsorbent layers 71 are arranged in parallel, but the number of adsorbent layers 71 is not limited thereto. The number of adsorbent layers 71 is, for example, 5 or more, preferably 10 or more, and more preferably 20 or more. The gap between adjacent adsorbent layers 71 in the plurality of adsorbent layers 71 is, for example, 0.5 cm or more and 1.5 cm or less.

[0118] Each of the plurality of adsorbent layers 71 includes a flexible fiber member 73 and a plurality of granular adsorbents 72 .

[0119] The flexible fiber component 73 allows the passage of gas and restricts the passage of the granular adsorbent material. Typically, the flexible fiber component 73 is formed into a hollow shape (bag shape) capable of accommodating a plurality of granular adsorbent materials 72. The flexible fiber component 73 may be a fabric or a non-woven fabric. Examples of the material of the flexible fiber component 73 include organic fibers and natural fibers, preferably polyethylene terephthalate fibers, polyethylene fibers, and cellulose fibers. The thickness of the flexible fiber component 73 is, for example, not less than 25 μm and not more than 500 μm.

[0120] A plurality of granular adsorbent materials 72 are filled inside a flexible fiber member 73 having a hollow shape (bag shape). The granular adsorbent material 72 functions as an acid gas adsorbent, and typically functions as a carbon dioxide adsorbent. As the material of the granular adsorbent 72, for example, a material modified with the above-mentioned acid gas adsorbent can be cited, preferably cellulose modified with the above-mentioned acid gas adsorbent can be cited, and more preferably nanofibrillated cellulose modified with the above-mentioned acid gas adsorbent can be cited. The average primary particle size of the granular adsorbent 72 is, for example, not less than 60 μm and not more than 1200 μm. The filling ratio of the granular adsorbent 72 in the adsorbent layer 71 can adopt any appropriate value.

[0121] The acid gas adsorption device 7 shown in the figure further includes a plurality of spacers 74. The spacers 74 are sandwiched between the adjacent adsorption material layers 71 among the plurality of adsorption material layers 71. Thus, the spacing between the adjacent adsorption material layers can be stably ensured. In one embodiment, the plurality of adsorption material layers 71 and the plurality of spacers 74 are arranged such that: from a direction orthogonal to the thickness direction of the adsorption material layer 71 ( Figure 1 When viewed in the depth direction of the paper, it becomes a roughly Z shape.

[0122] As such an acid gas adsorption device 7, for example, there can be mentioned a gas separation unit described in International Publication No. 2014 / 170184, the entire contents of which are incorporated herein by reference.

[0123] In another embodiment, if Figure 5 and Figure 6 As shown, the first block 11 a typically includes a substrate 3 and an acidic gas adsorption layer 4 .

[0124] The structure of the substrate 3 is not particularly limited, and examples thereof include a honeycomb structure, a filter structure such as filter cloth, and a particle structure. The acid gas adsorption layer 4 may be disposed on the surface of the substrate 3 and is not particularly limited.

[0125] B-1. Base material (honeycomb base material)

[0126] In one embodiment, the substrate 3 is a honeycomb substrate 3 a . The honeycomb substrate 3 a includes partition walls 32 defining a plurality of cells 33 .

[0127] The cells 33 extend from the first end face E1 (inflow end face) to the second end face E2 (outflow end face) of the honeycomb substrate 3a in the longitudinal direction (axial direction) of the honeycomb substrate 3a (see Figure 6). The cell 33 has any appropriate shape in the cross section of the honeycomb substrate 3a in the direction perpendicular to the length direction. Examples of the cross-sectional shape of the cell include: a triangle, a quadrilateral, a pentagon, a polygon larger than a hexagon, a circle, and an ellipse. The cross-sectional shape and size of the cell may be all the same or at least partially different. Among the cross-sectional shapes of such cells, preferably a hexagon or a quadrilateral can be mentioned, and more preferably a square, a rectangle or a hexagon can be mentioned.

[0128] The cell density in the cross section of the honeycomb substrate in a direction perpendicular to the longitudinal direction (i.e., the number of cells 33 per unit area) can be appropriately set according to the purpose. For example, the cell density can be 4 cells / cm 2 ~320 compartments / cm 2 When the cell density is within such a range, the strength and effective GSA (geometric surface area) of the honeycomb substrate can be sufficiently ensured.

[0129] The honeycomb substrate 3a has any appropriate shape (overall shape). As the shape of the honeycomb substrate, for example, there can be cited: a cylindrical shape with a circular bottom surface, an elliptical cylindrical shape with an elliptical bottom surface, a prism shape with a polygonal bottom surface, and a column shape with an irregular bottom surface. The honeycomb substrate 3a shown in the figure has a prism shape. The outer diameter and length of the honeycomb substrate can be appropriately set according to the purpose. Although not shown in the figure, the honeycomb substrate can have a hollow area in the center of the cross section in a direction perpendicular to the longitudinal direction.

[0130] Typically, the honeycomb substrate 3a includes an outer wall 31 and partition walls 32 located inside the outer wall 31. In the example shown in the figure, the outer wall 31 and the partition walls 32 are formed integrally. The outer wall 31 and the partition walls 32 may be separate bodies.

[0131] In the example shown in the figure, the outer wall 31 has a square tube shape. The thickness of the outer wall 31 can be set arbitrarily and appropriately. The thickness of the outer wall 31 is, for example, 0.1 mm to 10 mm.

[0132] The partition wall 32 defines a plurality of compartments 33. More specifically, the partition wall 32 includes a first partition wall 32a and a second partition wall 32b that are orthogonal to each other, and the first partition wall 32a and the second partition wall 32b define a plurality of compartments 33. The cross-sectional shape of the compartment 33 is substantially quadrilateral. It should be noted that the configuration of the partition wall is not limited to the above-mentioned partition wall 32. The partition wall includes: a first partition wall extending in a radial direction, and a second partition wall extending in a circumferential direction, which can define a plurality of compartments.

[0133] The thickness of the partition wall 32 can be appropriately set according to the purpose of the acid gas adsorption device. Typically, the thickness of the partition wall 32 is thinner than the thickness of the outer wall 31. The thickness of the partition wall 32 is, for example, 0.03 mm to 0.6 mm. The thickness of the partition wall is measured by, for example, cross-sectional observation based on a SEM (scanning electron microscope). If the thickness of the partition wall is within such a range, the mechanical strength of the honeycomb substrate can be sufficient, and the opening area (the total area of ​​the cells in the cross section) can be sufficient.

[0134] The porosity of the partition walls 32 can be appropriately set according to the purpose. The porosity of the partition walls 32 is, for example, 15% or more, preferably 20% or more, and, for example, 70% or less, preferably 45% or less. The porosity can be measured by, for example, mercury penetration.

[0135] The bulk density of the partition walls 32 can be appropriately set according to the purpose. For example, the bulk density is 0.10 g / cm 3 Above, preferably 0.20 g / cm 3 Above, for example, 0.60 g / cm 3 Below, preferably 0.50g / cm 3 Hereinafter, the bulk density can be measured by, for example, mercury intrusion porosimetry.

[0136] As a material constituting the partition wall 32, ceramics can be cited representatively. As ceramics, for example, silicon carbide, silicon-silicon carbide composite materials, cordierite, mullite, alumina, silicon nitride, spinel, silicon carbide-cordierite composite materials, lithium aluminum silicate and aluminum titanate can be cited. The material constituting the partition wall can be used alone or in combination. Among the materials constituting the partition wall, cordierite, alumina, mullite, silicon carbide, silicon-silicon carbide composite materials and silicon nitride can be cited preferably, and silicon carbide and silicon-silicon carbide composite materials can be cited more preferably.

[0137] Typically, such a honeycomb substrate 3a is produced by the following method. First, a binder and water or an organic solvent are added to the material powder containing the above-mentioned ceramic powder as needed, and the obtained mixture is kneaded to form a blank, and the blank is molded (typically extrusion molded) into a desired shape, and then dried and fired as needed to produce the honeycomb substrate 3a. In the case of firing, for example, the firing is performed at 1200°C to 1500°C. The firing time is, for example, 1 hour or more and 20 hours or less.

[0138] B-2. Acidic gas adsorption layer (carbon dioxide adsorption layer)

[0139] In one embodiment, the acid gas adsorption layer 4 is formed on the surface of the partition wall 32. In the honeycomb substrate 3a, a flow path 34 is formed in a portion (representatively, a central portion) of the cross section of the cell 33 where the acid gas adsorption layer 4 is not formed. The acid gas adsorption layer 4 may be formed on the entire inner surface of the partition wall 32 (i.e., in a manner that surrounds the flow path 34) as shown in the example of the figure, or may be formed on a portion of the surface of the partition wall. If the acid gas adsorption layer 4 is formed on the entire inner surface of the partition wall 32, the adsorption efficiency of the acid gas (representatively, CO2) can be improved.

[0140] The flow path 34 extends from the first end face E1 (inflow end face) to the second end face E2 (outflow end face) in the same manner as the compartment 33. The cross-sectional shape of the flow path 34 may be the same as that of the compartment 33, preferably a hexagon or a quadrilateral, more preferably a square, a rectangle or a hexagon. The cross-sectional shape and size of the flow path 34 may be the same in all or may be at least partially different.

[0141] Typically, in an adsorption step described later, a fluid containing an acidic gas is supplied to the cell 33 (more specifically, the flow path 34 ).

[0142] The acid gas adsorption layer 4 contains an acid gas adsorption material corresponding to the acid gas to be adsorbed.

[0143] In one embodiment, the acidic gas adsorbent layer 4 further includes a porous carrier in addition to the above-mentioned acidic gas adsorbent. In this case, the acidic gas adsorbent is typically supported on the porous carrier so as to face the flow path. If the acidic gas adsorbent layer includes a porous carrier, it is possible to suppress the acidic gas adsorbent from falling off from the acidic gas adsorbent layer during the adsorption process and / or the desorption process.

[0144] The porous carrier can form mesopores in the acidic gas adsorbent layer. Examples of porous carriers include: organometallic structures (MOFs) such as MOF-74, MOF-200, and MOF-210; activated carbon; nitrogen-doped carbon; mesoporous silica; mesoporous alumina; zeolite; carbon nanotubes; fluorinated resins such as polyvinylidene fluoride (PVDF), preferably: organometallic structures (MOFs), activated carbon, PVDF, zeolite, mesoporous silica, and mesoporous alumina. The porous carrier can be used alone or in combination. The porous carrier preferably uses a material different from the acidic gas adsorbent.

[0145] The BET specific surface area of ​​the porous carrier is, for example, 50 m 2 / g or more, preferably 500m 2If the surface area of ​​the porous carrier is greater than the above lower limit, the acid gas adsorbent can be stably supported, thereby improving the adsorption efficiency of the acid gas. The upper limit of the BET specific surface area of ​​the porous carrier is typically 2000 m 2 / g or less.

[0146] When the acid gas adsorption material layer contains the acid gas adsorption material and the porous carrier, the total content ratio of the acid gas adsorption material and the porous carrier in the acid gas adsorption material layer is, for example, 30 mass% or more, preferably 50 mass% or more, and, for example, 100 mass% or less, preferably 99 mass% or less.

[0147] The content ratio of the acidic gas adsorbent in the acidic gas adsorbent layer is, for example, 30% by mass or more, preferably 50% by mass or more, and, for example, 99% by mass or less. The content ratio of the porous carrier is, for example, 0.01 parts by mass or more, preferably 0.3 parts by mass or more, and, for example, 0.7 parts by mass or less, preferably 0.5 parts by mass or less, relative to 1 part by mass of the acidic gas adsorbent. If the content ratio of the porous carrier is within the above range, the acidic gas adsorbent can be supported more stably.

[0148] In addition, the acid gas adsorbent layer may be composed only of the acid gas adsorbent. In this case, the acid gas adsorbent is directly supported on the partition wall 32 and faces the flow path. When the acid gas adsorbent layer is composed only of the acid gas adsorbent, the content of the acid gas adsorbent in the acid gas adsorbent layer is typically 95.0 mass % or more and 100 mass % or less. If the content of the acid gas adsorbent is within the above range, it is possible to stably ensure excellent acid gas adsorption efficiency.

[0149] Typically, such an acidic gas adsorbent layer is produced by the following method. The above-mentioned acidic gas adsorbent is dissolved in a solvent to prepare a solution of the acidic gas adsorbent. In addition, the above-mentioned porous carrier is added to the solvent as needed. There is no particular restriction on the order of adding the acidic gas adsorbent and the porous carrier. Thereafter, the solution of the acidic gas adsorbent is applied to a substrate (specifically, a partition wall), and then the coating is dried and sintered as needed to form an acidic gas adsorbent layer.

[0150] In addition, the acidic gas adsorption layer 4 may include the above-mentioned acidic gas adsorbing particles and the above-mentioned binder (a hydrophobic binder or a hydrophilic binder).

[0151] The total content of the acidic gas adsorbing particles and the binder in the acidic gas adsorbing layer 4 is, for example, 30 to 100 volume %, preferably 50 to 99 volume %. The volume % can be measured by, for example, microstructure observation or elemental analysis.

[0152] The content of the acid gas adsorbing particles in the acid gas adsorption layer 4 is, for example, 5% by volume or more, preferably 30% by volume or more. The upper limit of the content of the acid gas adsorbing particles is typically 85% by volume. If the content of the acid gas adsorbing particles is within such a range, the acid gas adsorption performance of the acid gas adsorption device can be sufficiently ensured.

[0153] The content of the binder in the acid gas adsorption layer 4 is, for example, 5% by volume or more, preferably 15% by volume or more. The upper limit of the content of the binder is typically 70% by volume. If the content of the binder is within such a range, it is possible to suppress the acid gas adsorption particles from falling off from the acid gas adsorption layer in the recovery method described later.

[0154] Typically, such an acidic gas adsorbent layer is produced by the following method. First, the above-mentioned binder is dissolved in a solvent to prepare a binder solution. Next, the acidic gas adsorbent particles are dispersed in the binder solution. Thereafter, the binder solution in which the acidic gas adsorbent particles are dispersed is applied to a substrate (specifically, a partition wall), and then the coating is dried to form the acidic gas adsorbent layer.

[0155] C. Acid Gas Recovery Method

[0156] Next, a method for recovering acid gas using an acid gas adsorption device according to an embodiment of the present invention will be described. Typically, the method for recovering acid gas includes an adsorption step and a desorption step in sequence.

[0157] In the adsorption process, a fluid containing acid gas is supplied to the acid gas adsorption unit 1 adjusted to a predetermined adsorption temperature. At this time, the fluid containing acid gas first flows into the first adsorption unit 11 (more specifically, the flow path 34 of the first block 11a) through the first opening 21 of the shell 2. As a result, the acid gas adsorbent contained in the first adsorption unit 11 adsorbs the acid gas from the fluid containing acid gas (representatively CO2). At this time, poisoning and deterioration components contained in the fluid sometimes adhere to the acid gas adsorption layer 4 of the first adsorption unit 11. Thereafter, the fluid that has passed through the first adsorption unit 11 flows into the second adsorption unit 12. As a result, the acid gas adsorbent contained in the second adsorption unit 12 adsorbs the acid gas from the fluid. As a result, the acid gas is adsorbed from the fluid supplied to the acid gas adsorption unit. Thereafter, the fluid that has passed through the first adsorption unit 11 and the second adsorption unit 12 in sequence is discharged from the second opening 22.

[0158] The temperature of the acid gas adsorption unit in the adsorption process (adsorption temperature) is, for example, 0° C. or more, preferably 10° C. or more, and, for example, 50° C. or less, preferably 40° C. or less. In one embodiment, the adsorption temperature is the same as the outside air temperature. The implementation time of the adsorption process (adsorption time) is, for example, 15 minutes or more, preferably 30 minutes or more, and, for example, 3 hours or less, preferably 2 hours or less.

[0159] When the adsorption temperature and / or the adsorption time are within the above ranges, the acid gas adsorbent can efficiently adsorb the acid gas.

[0160] The acid gas adsorption rate in the adsorption process (=100-(acid gas concentration in the fluid that has passed through the acid gas adsorption section / acid gas concentration in the fluid before being supplied to the acid gas adsorption section×100)) is, for example, 60% or more, preferably 75% or more, more preferably 80% or more, and, for example, 90% or less.

[0161] Next, in the desorption process, the acid gas adsorption unit 1 is typically heated to a desorption temperature exceeding the adsorption temperature. More specifically, in the desorption process, after the acid gas adsorption unit 1 is heated to the desorption temperature, the temperature is maintained at the desorption temperature for a predetermined desorption time. Thus, the acid gas adsorbed by the acid gas adsorbent in the adsorption process is desorbed from the acid gas adsorbent. Therefore, the desorbed acid gas can be recovered.

[0162] In one embodiment, in the desorption process, the desorbed gas is supplied to the acid gas adsorption unit 1, and the desorbed gas passes through the first adsorption unit 11 and the second adsorption unit 12 in sequence, thereby recovering the desorbed acid gas together with the desorbed gas. The gas recovered in the desorption process is sometimes referred to as recovered gas. As the desorbed gas, it is preferred to cite the recovered gas that has been previously recovered by the acid gas adsorption device. By using the recovered gas as the desorption gas, the acid gas concentration in the recovered gas can be increased.

[0163] It should be noted that in the desorption process, the acid gas can be recovered without using the desorption gas. For example, the desorption acid gas can be sucked and recovered by a pressure reducing pump. In addition, the desorption gas and the pressure reducing pump can be used in combination.

[0164] The temperature of the acid gas adsorption unit in the desorption process (desorption temperature) is, for example, 70° C. or more, preferably 80° C. or more, and, for example, 200° C. or less, preferably 110° C. or less. The implementation time of the desorption process (desorption time during which the acid gas adsorption unit is maintained at the desorption temperature) is, for example, 1 minute or more, preferably 5 minutes or more, and, for example, 1 hour or less, preferably 30 minutes or less. If the desorption temperature and / or the desorption time are within the above ranges, the acid gas can be sufficiently desorbed from the acid gas adsorbent.

[0165] The above operation can efficiently recover the acidic gas. The adsorption step and the desorption step are preferably repeated in sequence. In one embodiment, the adsorption step and the desorption step are cyclically performed, for example, 10 times or more, preferably 30 times or more, more preferably 50 times or more, and further preferably 100 times or more.

[0166] D.Replacement method

[0167] Next, a replacement method of the first adsorption unit according to one embodiment of the present invention will be described.

[0168] In one embodiment, the first adsorption unit is replaced after the adsorption step and the desorption step are performed (preferably after the adsorption step and the desorption step are cycled within the above range). Alternatively, the first adsorption unit may be replaced after the acid gas adsorption rate in the adsorption step falls below the above lower limit.

[0169] In the replacement method of the first adsorption unit, first, the used first adsorption unit 11 is taken out from the inside of the housing 2. For example, the first adsorption unit 11 is pulled out from the inside of the housing 2 to the outside through an opening provided in the housing 2. Alternatively, the first adsorption unit 11 may be taken out of the housing 2 by removing a portion of the housing 2 on the upstream side of the acid gas adsorption unit 1.

[0170] After that, in one embodiment, a new first adsorption unit 11 is installed in the housing 2. Thus, the replacement of the first adsorption unit is completed.

[0171] In addition, if Figure 7 As shown, when the size of the second adsorption part 12 is the same as that of the first adsorption part 11, after the first adsorption part 11 is taken out of the housing 2 after use, the second adsorption part 12 is moved toward the upstream side in the passing direction of the fluid. In this way, the second adsorption part 12 can be set as the next first adsorption part 11. Based on this, the first adsorption part can also be replaced.

[0172] When the acidic gas adsorption unit 1 includes the nth adsorption unit 13 (third adsorption unit 133 ), the nth adsorption unit 13 (third adsorption unit 133 ) may be moved upstream in the fluid passing direction to be the next second adsorption unit 12 .

[0173] Afterwards, if Figure 8 As shown, as needed, an nth adsorption unit is added to the downstream end of the acid gas adsorption unit 1 in the passing direction of the fluid. For example, the new nth adsorption unit is inserted into the inside of the housing 2 through the opening provided in the housing 2. Alternatively, the portion of the housing 2 on the downstream side of the acid gas adsorption unit 1 may be removed, and the new nth adsorption unit may be arranged inside the housing 2.

[0174] Industrial Applicability

[0175] The acid gas adsorption device according to the embodiment of the present invention is used for separation and recovery of acid gas, and can be particularly well used in a carbon dioxide recovery, utilization and storage (CCUS) cycle.

[0176] Explanation of symbols

[0177] 1 Acid gas adsorption unit

[0178] 11. First adsorption unit

[0179] 12. Second adsorption unit

[0180] 2. Housing

Claims

1. An acid gas adsorption device, comprising: an acid gas adsorption unit, the acid gas adsorption unit including an acid gas adsorption material capable of adsorbing acid gas, and a fluid can pass through in a predetermined direction; and a housing, The acid gas adsorption unit is divided into at least: A first adsorption portion, the first adsorption portion including an upstream end surface in a passing direction of the fluid; and a second adsorption portion, the second adsorption portion being located on a downstream side of the first adsorption portion in a passing direction of the fluid, The one housing accommodates the first adsorption part and the second adsorption part together. The first adsorption portion and / or the second adsorption portion is divided into a plurality of parts in a direction intersecting with a passing direction of the fluid.

2. The acid gas adsorption device according to claim 1, wherein: The acid gas is carbon dioxide.

3. The acid gas adsorption device according to claim 1 or 2, wherein: In the passing direction of the fluid, a size of the second adsorption portion is substantially the same as a size of the first adsorption portion.

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