JP5328110B2 - Cylindrical activated carbon filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylindrical activated carbon filter with low pressure loss and excellent contact efficiency with treating gas. <P>SOLUTION: There are provided a cylindrical activated carbon filter formed by concentrically combining cylindrical inner and outer casings having gas permeability and by filling ether-based polyurethane foam with activated carbon particles fixed between the inner and outer casings, and a deodorizing method using the cylindrical activated carbon filter. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a deodorizing activated carbon filter applied to a deodorizing apparatus that removes an odor component by passing a treatment gas containing an odor.

  Deodorizing devices using activated carbon are widely used in various sewerage treatment facilities, human waste treatment plants, industrial treatment water treatment facilities, and the like. Among the sewage treatment facilities, deodorizing filters that have low pressure loss, high removal performance, and good handling are particularly desired in the deodorization of odors discharged from rainwater catchment ponds, rainwater adjustment ponds, rainwater discharge chambers, etc. Yes. For example, in Non-Patent Document 1, a filter using a macaroni cross charcoal (a powdered activated carbon formed into a macaroni shape and having a cross support inside the inner diameter), a filter using an activated carbon honeycomb, a cylindrical cartridge Describes a filter filled with activated carbon. Moreover, there are Patent Documents 1 to 3 as patents corresponding to them.

  In the case of a filter using macaroni cross charcoal, the adsorbent used has a diameter of 15.2 mmφ, outer wall thickness of 3.4 mm, cross rib thickness of 2.0 mm, and length of 18.2 mm (Patent Document 2). Although the loss was kept low, there was a problem that the removal area was low because the contact area with the gas was small. In order to improve the removal performance, there is a method of increasing the amount of adsorbent used, but this is not appropriate because it involves an increase in pressure loss. Further, since molding is very difficult, no method has been implemented to increase the contact area with the gas by reducing the diameter of the adsorbent or increasing the diameter of the through hole.

In the case of a filter using honeycomb activated carbon, the number of honeycomb cells used is usually about 200 to 300 cells / inch ² , so the pressure loss is low and the removal rate is high, but the filter is easy to break. There is a problem that filling and exchanging work is very troublesome. Further, since the cost of the honeycomb is higher than that of normal granular activated carbon, there is a problem that the initial cost and the running cost are increased.

In the case of a filter in which a cylindrical cartridge is filled with activated carbon, there is an advantage that the replacement work of the filter is very easy. However, since the cylindrical cartridge having a cylindrical cartridge with a width of about 15 to 50 mm is filled with a columnar activated carbon having a particle size of about 1.5 to 5 mm or a crushed activated carbon, Although the pressure loss is low, there is a problem that sufficient removal performance cannot be obtained because the contact time between the processing gas and activated carbon is short. In order to improve the removal performance, a method of reducing the SV (space velocity) and maintaining a sufficient contact time is used. However, in this case, the amount of processing gas is reduced or the apparatus is increased in size, which is not preferable. . Further, there is a method of reducing the particle size of the activated carbon to improve the contact property between the treatment gas and the activated carbon, but this is not preferable because the pressure loss increases.
JP 7-42202 A Japanese Patent Laid-Open No. 2002-68524 JP 2004-148165 A "Technical data on low-concentration simple deodorization equipment" by Japan Sewage New Technology Promotion Organization-March 2005

  An object of the present invention is to provide a cylindrical activated carbon filter having low pressure loss and excellent contact efficiency with a gas to be treated.

  As a result of intensive studies to solve the problems described in the background art, the inventor obtained an adsorbent obtained by fixing activated carbon particles having a particle diameter of 0.01 to 1.0 mm to a sheet-like ether polyurethane foam. The present inventors have found that a filter filled in a spiral shape between a cylindrical inner and outer case having air permeability has low pressure loss and excellent contact efficiency with a processing gas. As a result of further research based on this knowledge, the present invention has been completed.

  That is, the present invention relates to the following cylindrical activated carbon filter.

  Item 1. A cylindrical activated carbon filter formed by concentrically combining cylindrical inner and outer cases having air permeability and filling an ether polyurethane foam having activated carbon particles fixed between the inner and outer cases.

  Item 2. Item 2. The cylindrical activated carbon filter according to Item 1, wherein the shape of the ether polyurethane foam is a sheet, and a laminate of the sheet ether polyurethane polyurethane is filled between the inner and outer cases.

  Item 3. Item 3. The cylindrical activated carbon filter according to Item 2, wherein the laminate is obtained by laminating the sheet-like ether-based polyurethane foam in a spiral shape.

  Item 4. Item 4. The cylindrical activated carbon filter according to any one of Items 1 to 3, wherein the activated carbon has a particle size of 0.01 to 1.0 mm.

  Item 5. Item 5. The cylindrical activated carbon filter according to any one of Items 1 to 4, wherein the ether-based polyurethane foam has a mesh-like open cell structure, and the number of cells (JIS K 6402) is 8 to 70/25 mm.

  Item 6. Item 6. The cylindrical activated carbon filter according to any one of Items 1 to 5, wherein the amount of the activated carbon adhered to the ether polyurethane foam is 0.08 to 0.25 g / ml.

  Item 7. The activated carbon is selected from the group consisting of non-immobilized activated carbon, acid-immobilized activated carbon, alkali-immobilized activated carbon, alkali metal halide-immobilized activated carbon, bromine-immobilized activated carbon, acid / alkali metal halide / bromine co-immobilized activated carbon, and mixtures thereof. Item 7. The cylindrical activated carbon filter according to any one of Items 1 to 6, which is at least one kind.

  Item 8. 8. A deodorizing method comprising deodorizing a gas to be treated containing an odor by passing it through the cylindrical activated carbon filter according to any one of Items 1 to 7.

  The cylindrical activated carbon filter of the present invention has low pressure loss and excellent contact efficiency with the processing gas. Further, since the activated carbon is fixed to the polyurethane foam, there is no scattering even in the case of powdered activated carbon.

  The cylindrical activated carbon filter of the present invention is formed by concentrically combining cylindrical mesh inner and outer cases and filling an ether polyurethane foam having activated carbon particles fixed between the two cases. The cylindrical activated carbon filter is not simply filled with activated carbon between the two cases, but is filled with sufficient ether-based polyurethane foam to which activated carbon particles are fixed, so that the pressure loss is low and the contact efficiency with the processing gas is low. It has the feature that it is excellent in.

  In the present invention, a reticulated ether-based polyurethane foam is used. Polyurethane foams include ether polyurethane foams and ester polyurethane foams. In general, ester polyurethane foam is often used in terms of heat resistance and strength. However, when an adsorbent in which activated carbon is fixed to the ester polyurethane foam is used, from the hydrogen sulfide adsorbed on the activated carbon. The generated sulfuric acid deteriorates the strength of the urethane foam, and the removal rate is reduced due to a short path due to the drift in the filter. Further, when the activated carbon in which acid or bromine is impregnated is fixed to the activated carbon, the strength is similarly deteriorated. On the other hand, ether-based polyurethane foams are preferably used because the above-mentioned problems do not occur.

  The type of the ether polyurethane foam is not particularly limited, and those produced by a known method using a polyether polyol, polyisocyanate, a foaming agent and a catalyst are used. Examples of the polyether-based polyol include those obtained by addition polymerization of alkylene oxide using propylene glycol, ethylene glycol, glycerin, trimethylolpropane, hexanetriol, or the like as a starting material. Examples of the polyisocyanate include 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), diphenylmethane-4,4′-diisocyanate (MDI), and polymethylene. Polyphenyl isocyanate is mentioned. Water is preferred as the foaming agent, but methylene chloride or the like may be used. Examples of the catalyst include amine catalysts such as triethylenediamine, tetramethylenehexadiamine and dimethylcyclohexylamine, and organic tin catalysts such as stannous octoate and dibutyltin dilaurate.

  The ether-based polyurethane foam is preferably a flexible sheet having a network-like open cell structure. The thickness is about 3 to 15 mm, preferably about 5 to 10 mm, and the number of cells (JIS K 6402) is 8 to 70/25 mm, preferably 8 to 30/25 mm. Such a polyurethane foam can be easily produced by a known method.

  Activated carbon particles are fixed to the network-like ether polyurethane foam using a binder.

  The activated carbon to be used is not particularly limited, and non-implanted activated carbon, acid-immobilized activated carbon, alkali-immobilized activated carbon, alkali metal halide-immobilized activated carbon, bromine-immobilized activated carbon, acid / alkyl halide / bromine co-immobilized activated carbon, or a mixture thereof is used. It is done.

  Examples of activated carbon materials include plant materials such as wood powder and coconut shells, coals such as anthracite, petroleum pitch, coke, bituminous coal, lignite, petroleum-based materials, acrylic resins, phenol resins, epoxy resins, polyester resins, saran resins, etc. Synthetic resin-based raw materials, and the like, are preferably used. The aforementioned activated carbon raw material is activated, for example, in a fixed bed, a moving bed, a fluidized bed, or the like. For example, gas activation using water vapor, chlorine, hydrogen chloride, carbon monoxide, carbon dioxide, oxygen, sulfur dioxide, etc., potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, potassium sulfate, sodium sulfate, phosphorus There are chemical activations using chemicals such as acid, sodium phosphate, calcium chloride, potassium chloride or zinc chloride. The activated carbon used in the present invention (non-attached) may be activated by any of them. As the activation method, for example, a known method described in “New edition activated carbon basics and application” (published by Yuzo Sanada, Motoyuki Suzuki, Jun Fujimoto, Kodansha) is adopted.

The particle diameter of the activated carbon used is usually 0.01 to 1.0 mm, preferably 0.1 to 0.85 mm. When non-attached activated carbon is used, the specific surface area is such that the BET specific surface area by nitrogen adsorption under liquid nitrogen temperature conditions is 500 to 3000 m ² / g, preferably 1000 to 2000 m ² / g. The pore volume is usually 0.1 to 1.5 ml / g, preferably 0.2 to 1 ml / g, as measured by the CI method using nitrogen adsorption under liquid nitrogen temperature conditions. The average pore diameter is d = 4V ÷ S × 1000 (d: average pore diameter (nm), V: pore volume (ml / g), S: specific surface area (m ² / g) ) Is usually 0.5 to 5 nm, preferably 1 to 3.5 nm.

  The acid impregnated activated carbon is obtained by supporting an acid on the above-mentioned non-impregnated activated carbon. Examples of the acid include inorganic acids such as sulfuric acid, phosphoric acid, nitric acid, bromic acid and iodic acid, organic acids such as oxalic acid, tartaric acid, succinic acid, citric acid, malic acid and glutaric acid, or mixed acids thereof. Sulfuric acid, phosphoric acid and mixed acids thereof are preferred. The amount of acid supported is, for example, 1 to 40 parts by weight, preferably 5 to 20 parts by weight with respect to 100 parts by weight of activated carbon. Examples of the method for supporting the acid include a method in which activated carbon is immersed in an acid aqueous solution, the activated carbon is impregnated with an acid and dried as needed, and a method in which the activated carbon is sprayed with an acid or an acid aqueous solution and dried as necessary. .

  Examples of the alkali-impregnated activated carbon include those in which an alkali-free compound such as hydroxide and carbonate is supported on the above-mentioned non-implanted activated carbon. Examples of the hydroxide include sodium hydroxide, potassium hydroxide, lithium hydroxide, and cesium hydroxide, and examples of the carbonate include potassium carbonate and sodium carbonate. Sodium hydroxide, potassium carbonate, and sodium carbonate are preferable. The supported amount of hydroxide and carbonate is, for example, 0.1 to 30 parts by weight, preferably 1 to 25 parts by weight with respect to 100 parts by weight of activated carbon. Examples of the method for supporting the alkali metal compound include a method in which activated carbon is immersed in an alkaline aqueous solution and the activated carbon is impregnated with an acid and dried as necessary, and an activated carbon is sprayed on the activated carbon and dried as necessary. .

  Examples of the activated carbon impregnated with an alkali metal halide include those obtained by supporting an alkali metal halide on the above-mentioned impregnated activated carbon. As the alkali metal halide, alkali metal iodide is preferable, and specific examples include sodium iodide, potassium iodide, lithium iodide, cesium iodide, and the like, and potassium iodide is preferable. The supported amount of the alkali metal halide is, for example, 0.1 to 15 parts by weight, preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of activated carbon. Examples of the supporting method include a method of immersing activated carbon in an aqueous solution of an alkali metal halide and drying it as necessary, a method of spraying an aqueous solution of an alkali metal halide on activated carbon and drying it as necessary. .

  Bromine-impregnated activated carbon is obtained by supporting bromine on the above-mentioned non-implanted activated carbon. The amount of bromine supported is, for example, 1 to 30 parts by weight, preferably 3 to 20 parts by weight with respect to 100 parts by weight of activated carbon. As a method for supporting bromine, 1) a method of vaporizing bromine (99%) or a bromine-containing aqueous solution that is liquid at room temperature and using a carrier gas such as nitrogen to circulate and contact activated carbon filled in the container. 2) A method of immersing activated carbon in bromine or a bromine-containing aqueous solution at room temperature and drying as required. 3) Spraying a liquid bromine or bromine-containing aqueous solution directly on activated carbon at room temperature or using a sprayer or sprayer. 4) A method of spraying using a carrier gas such as, and drying if necessary. 4) A method of allowing bromine to stand in a container together with activated carbon and vaporizing and impregnating at room temperature.

  The acid / alkali metal halide / bromine co-immobilized activated carbon is obtained by supporting the acid / alkali metal halide / bromine on the non-immobilized activated carbon. The supported amount of acid is, for example, 1 to 40 parts by weight with respect to 100 parts by weight of activated carbon, the supported amount of alkali metal halide is, for example, 0.01 to 5 parts by weight with respect to 100 parts by weight of activated carbon, and the supported amount of bromine is For example, it is 0.1-30 weight part with respect to 100 weight part of activated carbon. Examples of the supporting method include a method in which the above three components are supported simultaneously or sequentially and then dried as necessary.

  The type of activated carbon to be used can be selected according to the odor of the place where the adsorption filter is installed. For example, in the deodorization of a rainwater storage tank, since the hydrogen sulfide concentration is high, among the above-mentioned activated carbons, alkali metal halide-added activated carbon (particularly potassium iodide-added activated carbon) is suitable.

The particle diameter of the activated carbon after impregnation is usually 0.01 to 1.0 mm, preferably 0.1 to 0.85 mm. When using an alkali-impregnated carbon or an alkali metal halide-added activated carbon, it is 50 to 2700 m ² / g, preferably 800 to 1800 m ² / g. The pore volume is usually 0.08 to 1.2 ml / g, preferably 0.16 to 0.8 ml / g, as measured by the CI method using nitrogen adsorption under liquid nitrogen temperature conditions. The average pore diameter is d = 4V ÷ S × 1000 (d: average pore diameter (nm), V: pore volume (ml / g), S: specific surface area (m ² / g) The value calculated in (1) is usually 0.6 to 8 nm, preferably 1 to 3 nm, with respect to acid-impregnated activated carbon, bromine-impregnated activated carbon, and acid / alkali metal halide / bromine co-implanted activated carbon. It is difficult to measure the specific surface area and pore volume by the nitrogen adsorption method under the conditions.

  As a binder for fixing the activated carbon particles to the polyurethane foam, a latex binder is used. Examples thereof include one or a mixture of two or more of the following synthetic rubber latexes. 1) Copolymer of butadiene polymer or butadiene and styrene, styrene derivative, (meth) acrylonitrile, isoprene, isobutylene, etc. 2) Copolymer of isoprene and styrene, styrene derivative, 3) Chloroprene polymer, or chloroprene Copolymers of styrene, styrene derivatives, (meth) acrylonitrile, isoprene, etc. 4) Copolymers of acrylic esters with styrene, styrene derivatives, vinyl chloride, vinyl acetate, acrylonitrile, methacrylates, etc. 5) Methacrylonitrile polymers and copolymers of methacrylonitrile and styrene, 6) vinyl acetate polymers, vinyl chloride polymers. These are water emulsions mainly obtained from emulsion polymerization, and the resin solid content concentration is 20 to 50% by weight, preferably 35 to 45% by weight.

  The amount of the binder used is about 0.01 to 0.1 g / ml as the resin solid content per unit volume of the ether-based polyurethane foam, and depends on the particle size of the activated carbon to be bonded, the number of polyurethane foam cells to be used, and the thickness. Determine the appropriate amount.

  The binder is applied to the ether-based polyurethane foam by an appropriate method such as brush coating, roller or spraying, and impregnation of the activated carbon in the polyurethane foam is uniformly performed by an appropriate method such as manual or mechanical vibration. Furthermore, heating and drying are performed at 60 to 90 ° C. for about 6 to 24 hours to fix the activated carbon to the polyurethane foam. The amount of the activated carbon fixed to the polyurethane foam is about 0.08 to 0.25 g / ml, preferably about 0.1 to 0.2 g / ml per unit volume of the polyurethane foam. Within such a range, the contact efficiency with the processing gas is high, and the removal performance is also good.

  The ether-based polyurethane foam obtained as described above is filled between cylindrical inner and outer cases having air permeability combined concentrically. The cylindrical inner and outer cases having air permeability are not particularly limited as long as they can hold ether-based polyurethane foam and have holes that allow ventilation. The shape of the vent is a structure in which holes having a shape such as a triangle, square, rectangle, rhombus, hexagon, octagon, and circle are regularly arranged, for example, a lattice shape, a mesh shape, a honeycomb shape, a corrugated shape, and the like Is exemplified.

  The filling method is not particularly limited as long as it is a uniform and dense filling method between the cylindrical inner and outer cases so that the flow of the gas to be treated does not cause unevenness or a short pass.

  For example, when the polyurethane foam is in the form of a sheet, a laminate in which the sheets are laminated can be filled between the cylindrical inner and outer cases. Specific examples of the laminated body include a cylindrical laminated body obtained by laminating the sheets in a spiral shape, and having a space that can be inserted into the outer periphery of the cylindrical inner case in the central axis direction. . Or the cylindrical laminated body which laminated | stacked two or more what shape | molded this sheet | seat in the cylinder shape may be sufficient. In the case of this laminate, there is an advantage that it can be filled uniformly in the cylindrical case and a high removal rate can be obtained, but a spiral laminate is preferred from the viewpoint of workability, productivity, yield, and the like.

  The layer height of the laminate is not particularly limited, but from the viewpoint of contact efficiency between the gas to be treated and activated carbon, it is 2 layers or more, preferably 4 layers or more, more preferably 5 layers or more at the portion through which the gas to be treated passes. It suffices to stack them. In particular, in the case of a cylindrical laminated body in which sheets are spirally laminated, voids are likely to become large at the winding start portion and winding end portion of the sheet, resulting in a reduction in removal rate. In order to avoid this, it is usually desirable to have 4 layers or more, and more preferably 5 layers or more.

  The above laminate may be filled as it is between the cylindrical inner and outer cases, but filling the case after covering the laminate with a nonwoven fabric or the like makes it easier to fill the case. It is preferable to fill the laminate after covering the laminate with a nonwoven fabric or the like.

  A specific embodiment of the cylindrical activated carbon filter of the present invention is shown in FIG. FIG. 1 is a longitudinal sectional view of a cylindrical activated carbon filter, wherein 1 is a filter main body, 2 is an inner case, 3 is an outer case, 4 is an ether-based polyurethane foam (spiral) to which activated carbon is fixed, 5 is a lid, And 6 indicate through holes.

  The filter body 1 is a cylindrical mesh-shaped inner case 2 and outer case 3 that are concentrically combined, and ether polyurethane foam having activated carbon fixed between the two cases is spirally filled. A lower end portion of the inner case 2 is opened and joined to a lower end edge portion of the outer case 3, and a lid 5 for closing the upper end opening portions of the inner case 2 and the outer case 3 is provided. After the ether polyurethane foam having the activated carbon fixed between the inner and outer cases 2 and 3 is spirally filled, the lid 5 is placed and fixed.

  The filter body 1 may be fitted to a pedestal (not shown) so as to be detachable as necessary. The form of the fitting is not particularly limited as long as the fitting is easy and the processing gas does not leak. The filter body 1 can also be a replaceable cartridge. When the deodorizing performance is lowered, the filter main body 1 may be removed from the base and replaced with a new filter main body 1.

  When the activated carbon filter of the present invention is applied to a deodorization tower, a plurality of filter bodies 1 may be provided on a common mounting base provided across a processing gas passage formed in the deodorization tower.

  As a deodorizing method using the above-mentioned filter, the processing gas containing odor can be forced to pass through the filter body 1 or naturally ventilated by a blower (not shown) to achieve deodorization. Moreover, when using for deodorizing rainwater reservoirs etc., it is also possible to deodorize by letting the odor pushed out by the water level raised by the inflow of rainwater pass through the filter body without using a blower. In FIG. 1, the processing gas containing odor is passed from the inner case 2 to the outer case 3, but the reverse is also possible.

  Examples of gas components to be treated in the cylindrical filter of the present invention include sulfur-based acidic compounds such as hydrogen sulfide, mercaptans such as methyl mercaptan; sulfur-containing compounds such as methyl sulfide and sulfides such as methyl disulfide; ammonia, Nitrogen-containing compounds such as amines such as monomethylamine, dimethylamine, and trimethylamine; organic carboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, and valeric acid; aromatics such as benzene, toluene, xylene, styrene, naphthalene, phenol, and xylol Group hydrocarbons and the like.

  Depending on these components, the type of activated carbon charged in the filter can be changed and used. For example, when organic carboxylic acids or aromatic hydrocarbons in the processing gas are to be removed, a filter in which non-impregnated activated carbon is fixed to urethane foam is preferably used. When a sulfur-based acidic compound such as hydrogen sulfide is to be removed, a filter in which alkali metal halide-added carbon is fixed to urethane foam or a filter in which alkali-added activated carbon is fixed to urethane foam is preferably used. When sulfur-containing compounds such as mercaptans such as methyl mercaptan and sulfides such as methyl sulfide and methyl disulfide are to be removed, a filter in which bromine-impregnated activated carbon is fixed to urethane foam is preferably used. When nitrogen-containing compounds such as amines such as ammonia, monomethylamine, dimethylamine, and trimethylamine are to be removed, a filter in which acid-impregnated activated carbon is fixed to urethane foam is preferably used. In the case where hydrogen sulfide, methyl mercaptan, methyl sulfide, methyl disulfide ammonia, and trimethylamine coexist in the processing gas, an acid / alkali metal halide / bromine simultaneous activated carbon is preferably used. In addition to the impregnated activated carbon described above, an adsorbent in which an appropriate impregnated activated carbon is fixed to urethane foam can be used according to the target gas. In addition, when many kinds of gases coexist in the processing gas, it is possible to process by flowing the gas in series so as to stack two or more cartridges.

  The temperature of the gas to be treated may be within a range where the adsorption ability by the activated carbon is not impaired, and is about 5 to 40 ° C., preferably about 15 to 35 ° C.

  The humidity of the gas to be treated is not limited as long as the adsorption ability by the activated carbon is not impaired, and is usually about 90% or less relative humidity and preferably about 80% or less relative humidity.

When the gas to be treated containing odorous components and harmful substances is brought into contact with the cylindrical filter, the gas flow direction is not particularly limited, and the gas may flow from the inside of the inner tower to the outside, or from the outside of the filter. Gas may flow inside. The linear flow velocity of the gas to be treated is usually about 0.1 to 0.6 m / sec, preferably about 0.15 to 0.45 m / sec, based on the area of the inner tower. The SV of the processing gas is usually 2000 to 48000 hr ⁻¹ , preferably about 3000 to 36000 hr ⁻¹ .

  The cylindrical filter of the present invention can be used in various facilities that generate odor components as described above. For example, malodor treatment from various chemical factories, food factories, feed factories, sewage treatment plants, human waste treatment plants, sludge treatment plants, rainwater treatment plants, garbage treatment plants, animal breeding facilities, animal experiment facilities, livestock facilities, various It can be used to remove odors and chemical substances discharged from research facilities.

  The cylindrical activated carbon filter of the present invention uses activated carbon with a small particle diameter in a state in which pressure loss is suppressed as compared with the case of passing through only the activated carbon in order to pass the treatment gas through the ether-based polyurethane foam to which the activated carbon is fixed. Since the contact area with the gas increases, the removal rate increases. Moreover, a remarkable effect is exhibited in terms of performance and environment such as no powdered activated carbon scattering.

  Hereinafter, the present invention will be specifically described with reference to examples and test examples, but the present invention is not limited thereto. “Part” means “part by weight”.

Example 1
Made from coconut shell carbonized material by steam activation, potassium iodide is added to 100 parts of crushed activated carbon with a particle size of 0.18 to 0.35 mm, a specific surface area of 1598 m ² / g, a pore volume of 0.724 ml / g, and an average pore diameter of 1.81 nm An aqueous solution containing 2 parts was sprayed and dried to obtain impregnated activated carbon.

  Cut the polyether urethane foam with open cell structure 13 cells / 25mm, thickness 7mm to 300mm × 950mm, and apply the latex binder to the surface so that it becomes 0.05g / ml per unit volume. After applying the impregnated activated carbon, drying was performed at 80 ° C. for 12 hours to fix the activated carbon to the urethane foam. At this time, the amount of activated carbon fixed on the urethane foam was 0.129 g / ml per unit volume.

  A cylindrical filter made of resin having an inner cylinder diameter of 34 mm, an outer diameter of 100 mm, and a length of 300 mm was filled with a spiral wound of this filler to obtain an activated carbon filter.

Example 2
Made from coconut shell as a raw material by steam activation, 100 parts of pulverized activated carbon having a particle size of 0.25 to 0.50 mm, a specific surface area of 1658 m ² / g, a pore volume of 0.748 ml / g, and an average pore diameter of 1.80 nm, potassium iodide 2 The aqueous solution containing the part was sprayed and dried to obtain impregnated activated carbon.

  The same urethane foam as in Example 1 was cut into 300 mm × 950 mm, and the same binder as in Example 1 was applied to the surface so as to be 0.04 g / ml per unit volume. And dried for 12 hours to fix the activated carbon to the urethane foam. At this time, the amount of activated carbon fixed on the urethane foam was 0.139 g / ml per unit volume.

  A cylindrical filter made of resin having an inner cylinder diameter of 34 mm, an outer diameter of 100 mm, and a length of 300 mm was filled with a spiral wound of this filler to obtain an activated carbon filter.

Example 3
Made of coconut shell as a raw material by steam activation, 100 parts of pulverized activated carbon having a particle size of 0.18 to 0.35 mm, a specific surface area of 1598 m ² / g, a pore volume of 0.724 ml / g, and an average pore diameter of 1.81 nm are mixed with potassium iodide 2 The aqueous solution containing the part was sprayed and dried to obtain impregnated activated carbon.

  Polyether urethane foam with an open cell structure of 20 cells / 25mm and a thickness of 5mm is cut into 300mm x 950mm, and the binder is 0.04g / ml per unit volume on the surface as in Example 1. After coating and applying the above-mentioned impregnated activated carbon, drying was performed at 80 ° C. for 12 hours to fix the activated carbon to the urethane foam. At this time, the amount of activated carbon fixed on the urethane foam was 0.160 g / ml per unit volume.

  A cylindrical filter made of resin having an inner cylinder diameter of 34 mm, an outer diameter of 100 mm, and a length of 300 mm was filled with a spiral wound of this filler to obtain an activated carbon filter.

Comparative Example 1
Made of coconut shell as a raw material by steam activation, 100 parts of columnar activated carbon having a particle size of 3.35 to 4.75 mm, a specific surface area of 1237 m ² / g, a pore volume of 0.533 ml / g, and an average pore diameter of 1.73 nm, potassium iodide 2 The aqueous solution containing the part was sprayed and dried to obtain impregnated activated carbon.

  This adsorbent was packed into a resin cylindrical filter having an inner cylinder diameter of 34 mm, an outer diameter of 100 mm, and a length of 300 mm to obtain an activated carbon filter.

Comparative Example 2
Made from coconut shell by steam activation, 100 parts of crushed activated carbon with a particle size of 1.70-3.35 mm, surface area of 1474 m ² / g, pore volume of 0.684 ml / g, average pore diameter of 1.84 nm, 2 parts of potassium iodide Sprayed with an aqueous solution containing, an impregnated activated carbon was obtained.

  This adsorbent was packed into a resin cylindrical filter having an inner cylinder diameter of 34 mm, an outer diameter of 100 mm, and a length of 300 mm to obtain an activated carbon filter.

Comparative Example 3
An activated carbon filter was obtained in the same manner as in Example 1 except that the polyether urethane foam was replaced with the polyester urethane foam.

  According to JIS K 6402, the number of cells is a number between 25 mm in length, counting the number of spaces on a straight line using a magnifying glass.

Test example 1 (comparison of pressure loss)
The pressure loss of the adsorbent produced in Examples 1 to 3 and the (adsorbent) activated carbon used in Comparative Examples 1 to 2 was measured. The pressure loss is measured by filling a cylinder of a predetermined size with an adsorbent and flowing air at 25 ° C. so that the gas flow rate is 0.15 to 0.5 m / sec. It was determined by measuring the differential pressure.

  The result is shown in FIG. From FIG. 4, the pressure loss of the adsorbents of Examples 1 to 3 was in the range of 1.5 to 2.7 kPa / m at a flow rate of 0.3 m / s. On the other hand, the pressure loss of the granular activated carbon having a particle size of 3.35 to 4.75 mm, which is the adsorbent of Comparative Example 1, was about 1 kPa / m, which was a lower value than that of the example. Moreover, the pressure loss of the pulverized activated carbon having a particle size of 1.70 to 3.35 mm, which is the adsorbent of Comparative Example 2, was 2.5 kPa / m, which was higher than that of Example 3. Further, the pressure loss is considered to increase by making the particle size finer.

  In Examples 1 to 3, activated carbon having a particle size smaller than that of Comparative Example 2 was used. However, it was confirmed that the pressure loss was lower than that of Comparative Example 2 by being fixed to urethane foam.

Test example 2 (comparison of hydrogen sulfide adsorption performance)
Examples 1-3 and Comparative Examples 1 to 2 25 ° C. containing hydrogen sulfide 10ppm in cylindrical diameter filter prepared in 50% relative humidity of the gas flow rate 0.20 gases ^{50 m} 3 / hr in the direction outward from the inside of the cartridge The sample was run at a rate of ˜0.25 m / sec, and the concentration at the filter outlet after 10 hours was measured. At this time, the gas temperature was 25 ° C. and the relative humidity was 80%. The hydrogen sulfide concentration was measured by a method in accordance with the method described in Appendix 2 of the Measurement Method for Specific Malodorous Substances Notification No. 9 of the Environment Agency.

  In the adsorbents of Examples 1 to 3, a hydrogen sulfide removal rate of 95% or more was obtained. On the other hand, in Comparative Example 1 and Comparative Example 2, the hydrogen sulfide removal rate was 81 to 85%, and a sufficient removal rate was not obtained.

  As shown in Test Examples 1 and 2 using the activated carbon filters of Comparative Examples 1 and 2, if the particle size of the adsorbent is reduced, the removal rate increases, but the pressure loss also tends to increase. In the activated carbon filters of Examples 1 to 3, the pressure loss is lower than that of Comparative Example 2 and high adsorption performance, although activated carbon having a particle size smaller than those of Comparative Examples 1 and 2 is used. It was confirmed that it was demonstrated.

Test Example 3 (Comparison of polyurethane foam)
Example 1 Preliminary 35 ° C. containing hydrogen sulfide 10ppm in cylindrical diameter filter manufactured in Comparative Example 3, the gas flow rate from the inside to the outside in the direction of the cartridge relative humidity of 90% of the gas ^50m 3 / hr ^0.20~0.25m Gas was allowed to flow for 200 hours under the conditions of / sec. When urethane foam was taken out of the cylindrical filter and a tensile strength test was performed based on JIS K6400, the strength in Example 1 was about 80% of that before use. In Comparative Example 3, the tensile strength test was performed. Only about 30% strength was retained. This is presumably because, in Comparative Example 3 using an ester polyurethane foam, the strength of the urethane was deteriorated by sulfuric acid generated from hydrogen sulfide adsorbed on the activated carbon.

It is a longitudinal cross-sectional view of the activated carbon filter which shows one Embodiment of this invention. It is a graph which shows the measurement result of the pressure loss using the adsorption agent of Examples 1-3 in Experiment 1, and the adsorption agent of Comparative Examples 1-2.

Explanation of symbols

1 Filter body 2 Inner case 3 Outer case 4 Ether-based polyurethane foam with activated carbon particles fixed 5 Lid 6 Through hole

Claims (5)

A cylindrical activated carbon filter formed by concentrically combining cylindrical inner and outer cases having air permeability, and filled with an ether polyurethane foam having activated carbon particles fixed between the inner and outer cases ,
The shape of the ether-based polyurethane foam is a sheet, and a laminate obtained by laminating the sheet-like ether-based polyurethane foam in a spiral shape is filled between the inner and outer cases,
The activated carbon is an acid-impregnated activated carbon in which an inorganic acid is supported on an unimpregnated activated carbon, an alkali-impregnated activated carbon in which a hydroxide is supported on an unaffected activated carbon, an alkali metal halide-added activated carbon, a bromine-added activated carbon, an acid / alkali metal halide. A cylindrical activated carbon filter that is at least one selected from the group consisting of activated carbon impregnated with bromine and mixtures thereof . The cylindrical activated carbon filter according to claim 1, wherein the activated carbon has a particle diameter of 0.01 to 1.0 mm. The cylindrical activated carbon filter according to claim 1 or 2 , wherein the ether-based polyurethane foam has a mesh-like open cell structure, and the number of cells (JIS K 6402) is 8 to 70 pieces / 25 mm. The cylindrical activated carbon filter according to any one of claims 1 to 3 , wherein a fixed amount of activated carbon to the ether polyurethane foam is 0.08 to 0.25 g / ml. The deodorizing method characterized by deodorizing the to-be-processed gas containing an odor through the cylindrical activated carbon filter in any one of the said Claims 1-4 .