JPH0257975B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for treating waste ozone. [Prior Art] and [Problems to be Solved by the Invention] Ozone (O ₃ ) is used in a wide range of fields because of its strong sterilizing and oxidizing power. For example, it is used for water treatment such as high-level treatment of wastewater, for deodorization in residential areas and production processes, and for food storage and medical fields. Table 1 shows the uses and fields of use of O ₃ .

[Means for solving problems]

_In view of the above-mentioned conventional demands and drawbacks of the conventional method, the present invention uses ion exchange fibers to treat waste O ₃ , especially low-concentration waste O ₃ with high efficiency. Depending on the source, type, etc.), the treatment is performed in combination with the conventional O ₃ treatment method described above, and waste O ₃ from a wide variety of sources can be treated more effectively in practice. That is, the present invention is a waste ozone treatment method characterized by bringing an ozone-containing gas into contact with ion exchange fibers obtained by supporting an ion exchanger on natural fibers or artificial fibers. In addition, the present invention applies ozone-containing gas to at least one of the following treatments: catalytic decomposition treatment using an ozone decomposition catalyst, adsorption decomposition treatment using activated carbon, thermal decomposition treatment by heating, and absorption treatment using a chemical solution. This is a waste ozone treatment method characterized by contacting an ion exchange fiber in which an ion exchanger is supported on an artificial fiber. The present invention will be explained in detail below. First, to explain ion exchange fibers, they are natural fibers, man-made fibers (chemical fibers or synthetic fibers), or blended yarns or mixed yarns of these fibers that support cation exchangers and/or anion exchangers. This can be done by directly supporting it on a fibrous support.
After making it into a woven, knitted or flocked form,
This can also be supported. In any case, it is sufficient that the fiber ultimately supports an ion exchanger. The natural fibers include wool, silk, etc., the chemical fibers include rayon and acetate, and the synthetic fibers include those made from hydrocarbon polymers and fluorine-containing polymers. Alternatively, polyvinyl alcohol, polyamide, polyester, polyacrylonitrile, cellulose, cellulose acetate, etc. can be used. Examples of the hydrocarbon polymer include polyethylene, polypropylene, polybutylene, polybutene, polystyrene, polyα-methylstyrene, polyvinylcyclohexane, polyvinyl alcohol, polyamide, cellulose, cellulose acetate,
Aliphatic, aromatic, or alicyclic polymers such as polyester, acrylic, polyurethane, or copolymers thereof are used. In addition, examples of the fluorine-containing polymer include polytetrafluoroethylene, polyvinylidene fluoride, ethylene-tetrafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and vinylidene-tetrafluoride-hexafluoride copolymer. A fluorinated propylene copolymer or the like is used. Furthermore, fibers made from natural materials such as wool, silk, cotton, and linen can also be used. A mixture of the above raw materials may also be used. These materials, that is, the support body is used as a porous material, and the support body can be easily grafted, has good O ₃ resistance,
A material with high mechanical strength and low cost is preferable, and can be appropriately selected in consideration of the shape of the device, economic efficiency, effectiveness, etc. When incorporating the ion exchange fiber into the O ₃ removal device, for example, a non-woven fabric, a woven fabric, a knitted fabric, a fibrous form, etc. are used as appropriate, and can be determined as appropriate in consideration of the O ₃ removal effect, economy, etc. . Note that the term "fibrous" refers to the state of ion-exchange fibers as they are, and can be applied in the form of filaments (long fibers) or fabrics. In addition, in the case of textiles, it can be constructed from multiple types of ion-exchanged fibers with different supports; for example, it can be constructed by using a blended yarn of multiple types of ion-exchanged fibers or by interweaving them. It is possible. Regarding ion exchange fibers, anion exchange fibers are more effective in O ₃ treatment than cation exchange fibers, but
In practice, since O ₃ is often accompanied by other odorous components and other pollutants, both anion exchange fibers and cation exchange fibers can be used for deodorizing purposes. For example, the former is an acidic gas (e.g.
H ₂ S, SO ₂ ), the latter being an alkaline gas (e.g.
They are effective in collecting and removing NH ₃ ). Next, as the ion exchanger, various cation exchangers or anion exchangers can be used without particular limitation. For example, bodies containing cation exchange groups such as carboxyl groups, sulfonic acid groups, phosphoric acid groups, and phenolic hydroxyl groups, anion exchangers such as primary to tertiary amino groups, quaternary ammonium groups, sulfonium groups, and phosphonium groups. Examples include group-containing bodies, or polymerized or condensed type ion exchangers containing both the positive and negative ion exchange groups, and homogeneous or heterogeneous types. Typical examples of these include condensation polymers of sodium phenolsulfonate and aldehydes or ketones; condensation polymers of aromatic amines and aldehydes or ketones; acrylic acid, methacrylic acid, vinylbenzenesulfonic acid, styrene, and ar-halomethyl. Styrene, acyloxystyrene, hydroxystyrene, aminostyrene, vinylpyridine, 2
-Methyl-5-vinylpyridine, 2-methyl-5
- Polymers of monomers having cationic or anionic exchange groups or groups convertible thereto, such as vinylimidazole, acrylonitrile, sulfuric acid, chlorosulfonic acid, and sulfonic acid. Copolymers of the above monomers with monomers having two or more double bonds such as vinylbenzene, trivinylbenzene, butadiene, ethylene glycol, divinyl ether, and ethylene glycol dimethacrylate, or polyethylene, polyvinyl fluorocarbon ether, and Ion exchangers include polymers obtained by graft polymerizing styrene onto tetrafluoroethylene, into which cationic and/or anionic ion exchange groups are introduced or converted into ion exchange groups as required. Next, as a method for supporting the ion exchanger on the support, for example, the support may be exposed to ultraviolet rays or α rays, β rays, etc.
Irradiating with ionizing radiation such as beams, electron beams, and gamma rays,
Alternatively, there is a method of treating with an oxidizing agent such as oxygen, ozone, chlorosulfonic acid, hydrogen peroxide, benzoyl peroxide, peracetic acid, etc. to graft a monomer that forms an ion exchanger to support this. Specifically, for example, ion exchange fibers can be obtained by irradiating polyethylene with radiation, immersing it in a solution containing hydroxystyrene monomer and isoprene, performing graft polymerization, and after the reaction, performing quaternary amination. [Example] An example of the present invention will be described based on the drawings.
The drawing is a flow sheet when a primary treatment using a conventional ozone decomposition catalyst and a secondary treatment using a packing body filled with ion exchange fibers according to the present invention (hereinafter referred to as an ion exchange filter) are used together. . That is, 1 is waste O ₃ released from an O ₃ reactor (not shown) in sewage treatment, and relatively high concentration waste O ₃ 1 is a catalyst which is a reactor formed by filling an ozone decomposition catalyst. It is decomposed to a relatively low concentration in the filling section 2, and then processed in an ion exchange filter 3 to become a treated gas 4 with an extremely low concentration (0.1 ppm or less) and discharged. The decomposition catalyst is usually a metal oxide catalyst such as MnO ₂ , Co oxide-added MnO ₂ , FeO, NiO, etc.
Catalysts in which noble metals such as Ag, Pt, and Pd are supported on SiO ₂ or γ-alumina, or Ag, Pd, etc. in semiconductor materials, etc.
A photocatalyst is used that adds noble metals such as Pt and Pd and irradiates with light. The catalyst in this example was Co
It is _MnO2 with oxide addition. The catalyst filling section 2 is used so that the O ₃ decomposition rate here is usually about 90 to 99%. That is, in the catalyst filling part 2, the O ₃ concentration is several ppm to several thousand ppm, usually several tens of ppm to
Several hundred ppm of waste O ₃ is treated until the concentration is about 1 to several tens of ppm. Next, the waste O ₃ 1 is treated by an ion exchange filter 3 to a concentration of about 1 to several tens of ppm to 0.1 ppm or less, usually 0.05 ppm or less. The filling amount of ion exchange fibers and the form of ion exchange fibers in the ion exchange filter 3 are determined by the concentration and concentration ratio of the substance to be removed (O ₃ alone or O ₃ and odor components), the shape and structure of the filled container, It may be determined as appropriate, taking into account the purpose, effect, etc. In this embodiment, the ion exchange filter 3 is filled with anion exchange fibers and cation exchange fibers at a volume ratio of 4:1, since the filter also serves to remove malodorous substances at a sewage treatment plant. This example is a case where a catalyst method is used as the primary treatment method for waste O ₃ , and this primary treatment method is as follows:
Any method that can process a relatively high concentration of O ₃ to a relatively low concentration may be used, but catalyst methods and activated carbon methods are preferred from the viewpoint of treatment efficiency, cost, operability, operation scale, etc. Preferred O ₃ treatment methods include a combination of primary treatment using conventional methods and secondary treatment using ion exchange fibers according to the present invention when waste O ₃ has a relatively high to medium concentration, and when waste O 3 has a relatively low concentration. Although it is reasonable to use ion-exchange fiber alone, it can be determined as appropriate by considering the type and scale of the waste O ₃ source, coexisting components, economic efficiency, effects, etc. Experimental Example 1 (1) Experimental Conditions Ozone from an ozone generator was passed through an ion exchange filter made of ion exchange fibers manufactured by the method described below at a rate of 1/min, and the ozone concentrations at the inlet and outlet were measured. Generator: Ozone generator using ultraviolet irradiation Generated ozone concentration (average concentration): 85ppm, 10ppm,
3ppm filter size: 100mm x 100mm x 30mm (2) Experimental results

〔Effect of the invention〕

1. By using ion exchange fibers as a waste O ₃ treatment method, waste O ₃ can be treated with high efficiency. The discharge O ₃ concentration can be reduced to a virtually negligible concentration. For both continuous and intermittent use. However, pollutants other than O ₃ (such as odorants, e.g.
At the same time, it is possible to collect and remove So ₂ , H ₂ S, NO _x , HCl, HNO ₃ , NH ₃ various solvents, solvents, malodorous substances (mercaptans, sulfides, thiophenes), tar-like substances or fine particles). 2. Waste O ₃ from a wide variety of sources can be treated by combining the method using ion-exchange fibers with the conventional O ₃ treatment method using ozone decomposition catalysts. In other words, this is a practically effective processing method that takes advantage of the strengths of each. Specifically, since the conventional O ₃ treatment method is based on a decomposition reaction, the higher the O ₃ concentration, the more
Effective. On the other hand, in the method using ion exchange fibers, adsorption is considered to be the main effect, so the lower the concentration, the more effective it is. Not only continuous operation and intermittent operation but also highly practical treatment is possible even when the waste O ₃ concentration fluctuates considerably.

[Brief explanation of the drawing]

The drawing is a flow sheet illustrating an embodiment of the invention. 1... Waste O ₃ , 2... Catalyst filling section, 3... Ion exchange filter, 4... Processing gas.

Claims (1)

[Scope of Claims] 1. A method for treating waste ozone, which comprises bringing an ozone-containing gas into contact with an ion exchange fiber in which an ion exchanger is supported on a natural fiber or an artificial fiber. 2. The treatment method according to claim 1, wherein the ion exchange fiber is processed into a woven fabric, knitted fabric, or nonwoven fabric and is brought into contact with an ozone-containing gas. 3. The treatment method according to claim 1, wherein the filling body formed by filling the filament or cloth of the ion exchange fiber is brought into contact with an ozone-containing gas. 4. Claim 1 in which the ion exchange fiber is one that supports an anion exchanger.
The processing method described in any one of Items 1 to 3. 5. The treatment method according to claim 4, wherein the ion exchange fiber is a natural fiber or an artificial fiber graft-polymerized with an ion exchanger. 6 After the ozone-containing gas is subjected to at least one of the following treatments: catalytic decomposition treatment using an ozone decomposition catalyst, adsorption decomposition treatment using activated carbon, thermal decomposition treatment by heating, and absorption treatment using a chemical solution, ions are added to natural or artificial fibers. A method for treating waste ozone, characterized by bringing it into contact with ion exchange fibers supporting an exchanger.