JP2015101858A - Deodorization method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deodorization method capable of suppressing a malodor emitted from a porous malodor emission part of a public toilet and the like.SOLUTION: A seal 4 between a porous urinal 3 and a floor surface 10, and a tile 11 on the floor surface 10 generate ammonia due to scattering of urine to be turned into a malodor generation part. Thus, a photocatalyst is sprayed on a scattering part, and photoirradiation is subsequently applied to the sprayed part to activate the photocatalyst and accelerate decomposition of an organic pollutant. Finally, cleaning is performed by using cleaning water into which a peroxide is mixed. Consequently, urea-splitting bacteria and the like on a surface of a porous part are inactivated.

Description

  The present invention relates to a deodorizing method for suppressing odor generated in, for example, a toilet.

  Although toilet toilets and urinals of toilets are regularly cleaned, odors are often generated with the passage of time of use, which often causes discomfort to the user. This phenomenon also occurs in flush toilets, and is recognized as a problem in toilets such as stations, vehicles, hotels, restaurants, schools, hospitals, etc., which are frequently used, rather than home toilets. For this reason, countermeasures are strongly demanded.

A typical example of odor is ammonia (NH ₃ ) generated when bacteria such as urea-decomposing bacteria and general bacteria decompose urea (CO (NH ₂ ) ₂ ). The urine discharged normally in the toilet bowl can be easily washed away with flush water if it is a flush toilet. However, urine droplets that are unintentionally scattered outside the toilet bowl and urine sprayed on the floor immediately below the toilet bowl cannot be washed out constantly, and are odor-producing sites. This phenomenon may occur regardless of whether it is a urinal, a urinal, or a Japanese-Western style toilet, but it can be said that the effect is greatest in the urinal in view of scattering outside the toilet.

  Further, since bacteria such as urea-decomposing bacteria and general bacteria are carried from dirt on shoes, odor may be generated again even if temporary measures are taken.

By the way, although the floor surface of a public facilities toilet is generally composed of floor tiles and sludge stone, each tile or block is often fixed by a joint made of mortar. However, the mortar material used as a joint is a porous material, and inside the porous material is a hotbed of bacteria such as ureolytic bacteria and general bacteria. Therefore, the joint is a main part of ammonia (NH ₃ ) generation.

In order to solve such problems, as a deodorizing method that does not require large-scale equipment, conventionally, an aromatic substance is placed in a toilet, and the odor caused by ammonia (NH ₃ ) is canceled by the fragrance emitted from the aromatic substance. A masking method and a method of adsorbing an odor component with an adsorbent are known.

The masking method is partially adopted depending on the place where it is applied. However, this method cannot suppress urea-decomposing bacteria that are the cause of ammonia (NH ₃ ) generation. Therefore, there is a problem that ammonia (NH ₃ ) is intermittently generated by newly scattered or dispersed urine, and there are also the following individual problems. That is, in the masking method, the odor component remains scattered in the surrounding environment, and therefore, if the amount of fragrant substances emitted decreases, the odor due to ammonia (NH ₃ ) becomes dominant and the user feels uncomfortable. doing. Because of these problems, the masking method is not suitable for the purpose of suppressing the return odor of a public facility toilet or the like having a strong odor, that is, the generation of odor again after the deodorization treatment.

  Next, the method of adsorbing the odor component with the adsorbent is costly because the adsorbent has a saturated adsorption amount and needs to be replaced every time the adsorbent reaches a saturated state. In addition, even if it has a predetermined suction force at the beginning of use, the suction force gradually decreases, eventually reaching saturation, and the effect is lost.

  On the other hand, as a deodorization method accompanied by installation of equipment, a conventional method of installing a deodorizer in a toilet and deodorizing by absorbing and decomposing odors, or a floor surface directly under a urinal as disclosed in Patent Document 1 A method is known in which an antifouling floor is installed below and the floor surface is not directly soiled as a receiving tray for scattered urine drops or urine.

However, even in the former method of installing a deodorizer in the toilet and deodorizing by absorbing / degrading odors, although there are some adoption depending on the place to apply, it is a factor of ammonia (NH ₃ ) generation There is a problem that urea-degrading bacteria cannot be suppressed and ammonia (NH ₃ ) is generated intermittently. In addition, the installation of equipment is expensive, and it is not suitable for the purpose of suppressing return odors such as toilets for public facilities that have a strong odor such as being left for a long time after cleaning and having urea-degrading bacteria adhered thereto.

Next, the latter method of installing a lower antifouling floor body on the floor surface directly under the urinal is to prevent urea from being decomposed by ureolytic bacteria even if urine is scattered or dispersed on the surface of the antifouling floor body. It can be evaluated in that no decomposition occurs. However, scattered urine and sprayed urine other than the installation surface travels down the floor surface, and urine is supplied to the ureolytic bacteria under the installation surface and ammonia (NH ₃ ) is generated, so that the return odor cannot be suppressed. have.

By the way, the method described above does not inactivate urea-decomposing bacteria that generate ammonia (NH ₃ ). Therefore, conventionally, a deodorizing operation for washing away the urea-decomposing bacteria while decomposing is also known.

In this method, for example, in addition to daily cleaning, urea is used by using cleaning water in which ozone (O ₃ ) or hydrogen peroxide (H ₂ O ₂ ), which has a strong cleaning power, is scattered on a scattered and dispersed floor surface. It is a deodorizing / cleaning method in which degrading bacteria are washed away while being decomposed.

This deodorization / cleaning method can directly suppress urea-decomposing bacteria that are the cause of ammonia (NH ₃ ) generation, and can suppress odor due to ammonia (NH ₃ ) immediately after cleaning. .

JP2013-126515A (released on June 27, 2013) JP 2013-121592 A (released on June 20, 2013)

  However, the conventional deodorization / cleaning method has a problem that the return odor cannot be suppressed. Specifically, in general public toilets, mortar is used as tile joints and seals on the floor. However, since the mortar material itself is porous, it is impossible to inactivate all of the urea-decomposing bacteria present in the porous interior by the above-described cleaning method. As a result, even when no new urine is supplied after cleaning, a return odor is generated again after a long time has passed since cleaning.

  Here, for example, Patent Document 2 discloses a purification device including a visible light responsive fibrous photocatalyst. In this purification device, a visible light responsive fiber photocatalyst is used to purify nitrogen monoxide (NO) contained in the exhaust gas of a vehicle or the like. However, Patent Document 2 does not disclose a deodorizing method for suppressing odor generated from a porous odor generating portion generated in a toilet or the like.

  This invention is made | formed in view of the said conventional problem, Comprising: The objective is to provide the deodorizing method which can suppress the odor which generate | occur | produces from the odor generating part which consists of porous.

  In order to solve the above problems, the deodorization method according to an aspect of the present invention includes a photocatalyst spraying step of spraying a photocatalyst on a porous odor generating part, and a light irradiation process of performing a light irradiation process on the spraying part of the photocatalyst. And a cleaning step of cleaning with cleaning water mixed with peroxide in this order.

  According to one aspect of the present invention, there is an effect of providing a deodorizing method capable of suppressing odor generated from a porous odor generating portion.

It is a flowchart which shows each process of the deodorizing method in Embodiment 1 of this invention. (A) is a side view which shows the structure of the toilet to which the said deodorizing method is applied, (b) is a top view which shows the structure of the toilet to which the said deodorizing method is applied. It is a flowchart which shows each process of the deodorizing method in Embodiment 2 of this invention. It is sectional drawing which shows the structure of the simple evaluation model of the deodorizing method in the verification experiment of this invention. It is a graph which shows the evaluation result of the verification experiment 1 in the deodorizing method of this invention. It is a graph which shows the evaluation result of the verification experiment 2 in the deodorizing method of this invention.

[Embodiment 1]
An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

  The deodorization method of this embodiment can be applied to deodorization of odors generated in, for example, household toilets or public toilets such as stations, vehicles, hotels, restaurants, schools, and hospitals. Further, the present invention is not limited to toilets such as household toilets and public toilets, and can be applied to odor control of odors such as sewage treatment plants, incineration plants, and waste storage facilities.

  Below, the case where the deodorizing method of this Embodiment is applied to the urinal 3 of the toilet 1 is demonstrated based on Fig.2 (a) (b). (A) of FIG. 2 is a side view which shows the structure of the toilet 1 to which the deodorizing method of this Embodiment is applied. FIG. 2B is a plan view showing the configuration of the toilet 1 to which the deodorizing method of the present embodiment is applied.

  The toilet 1 to which the deodorizing method of the present embodiment is applied has a urinal 3 attached to a wall surface 2 as shown in FIGS.

  The urinal 3 is in contact with the floor surface 10, for example, and a seal 4 is provided between the urinal 3 and the floor surface 10. The seal 4 is made of mortar which is a porous material. In addition, a large number of tiles 11 are laid on the floor 10, and mortar that is a porous material is also used for the joints 12 of these tiles 11. The mortar is a mixture of sand, cement, and water as fine aggregates. In the present specification, the porous material means a porous material to which urine and urate-degrading bacteria can enter.

  Accordingly, the seal 4 and the joint 12 correspond to the porous odor generating part of the present invention.

Although the toilet 1 of this Embodiment is common, in such a toilet 1, the urine which collided with the urinal 3 is scattered or dripped directly on the scattering / dropping part 13 of the floor surface 10. FIG. In the joint 12 as an odor generating part in the scattering / dropping part 13, urea (CO (NH ₂ ) ₂ containing bacteria such as urea-decomposing bacteria and general bacteria (hereinafter referred to as “urea-degrading bacteria”) in urine. ), Ammonia (NH ₃ ), which is a typical odor, is generated.

  Accordingly, the object of the deodorization method of the present embodiment is to provide a deodorization method capable of suppressing odors generated from a porous odor generating part.

  The deodorization method of this Embodiment is demonstrated based on FIG. FIG. 1 is a flowchart showing the deodorizing method of the present embodiment.

  As shown in FIG. 1, the deodorizing method according to the present embodiment first applies a photocatalyst to the scattering / dropping unit 13 including the seal 4 and the joint 12 as an odor generating unit including organic pollutants such as urea-decomposing bacteria. A photocatalyst spraying step of spraying is performed (S1). Then, the light irradiation process which performs light irradiation processing for a fixed time, for example, 2 hours is performed on the spraying part of the photocatalyst (S2). Further, after the light irradiation process, a cleaning process is performed (S3).

  Here, in this embodiment, in the photocatalyst spraying step (S1) and the light irradiation step (S2), the photocatalyst uses a visible light responsive photocatalyst material. However, the present invention is not necessarily limited to this, and an ultraviolet light-responsive photocatalyst can also be used.

For example, tungsten oxide (WO ₃ ) or titanium oxide (TiO ₂ ) can be used as the visible light responsive photocatalytic material.

  In the present embodiment, it is preferable to spray the photocatalyst as a slurry (suspension). This facilitates penetration into the mortar. In this case, the amount of the photocatalyst contained in the photocatalyst slurry is preferably 5 to 30% by weight, for example.

By the way, the photocatalyst has not only an oxidative decomposition activation action but also an oxidation / reduction action itself, and an organic pollutant decomposition action. That is, for example, when an electron in the valence band of titanium oxide (TiO ₂ ) is excited to the conduction band by ultraviolet light, the electron has a relatively strong reducing power. On the other hand, holes with very strong oxidizing power are also generated. Therefore, when an appropriate promoter is combined with titanium oxide (TiO ₂ ), water (H ₂ O) is oxidized into oxygen (O ₂ ) and hydrogen ions (H ⁺ ), and at the same time, water (H ₂ O) is converted into water (H ₂ O). It shows redox ability enough to reduce to hydrogen (H ₂ ) and hydroxide ion (OH ⁻ ).

As a result, when blue light is emitted from an LED (Light Emitting Diode) having visible light emission wavelength of, for example, 400 to 480 nm and emission intensity of, for example, 7 (mW / cm ² ), irradiation time However, the generation of odor can be suppressed in 20 hours, for example.

  Here, in the present embodiment, in the light irradiation step (S2), the range of the light irradiation process is as shown in FIG. 2B, in which the urine is scattered around the urinal 3 on the floor surface 10. This is performed in a light irradiation region 14 wider than the dropping unit 13. Moreover, the wavelength of light irradiation in a light irradiation process (S2) should just be a visible light wavelength band. If the light source for irradiating the photocatalyst spraying portion does not leak to the outside, or if it does not matter if it leaks to the outside, it is not necessary to use a visible light responsive type photocatalyst material. For this reason, it is also possible to irradiate ultraviolet light by spraying a photocatalyst made of an ultraviolet light responsive photocatalyst material that is available at a lower cost than the visible light responsive photocatalyst material.

  In the present embodiment, the light irradiation time in the light irradiation step is set to 20 hours, for example. However, as shown in Embodiment 2 and [Verification Experiment 2] to be described later, the irradiation time is shortened when the pre-cleaning step (S0) in which cleaning is performed using cleaning water mixed with peroxide is performed. It is possible.

Next, in this embodiment, after the photocatalyst spraying step (S1) and the light irradiation step (S2), a peroxide such as ozone (O ₃ ) water or hydrogen peroxide (H ₂ O ₂ ) water is used. Wash.

That is, since urine soaks inward from the surface of the porous portion, the concentration of the surface of the porous portion is high. Therefore, many urea decomposing bacteria etc. are cultured on the surface of the porous part. Ozone (O ₃ ) water or hydrogen peroxide (H ₂ O ₂ ) water does not penetrate into the porous portion. However, by performing a cleaning treatment with a cleaning water such as ozone (O ₃ ) water or hydrogen peroxide (H ₂ O ₂ ) water, the surface of the porous portion having a high concentration of urea decomposing bacteria or the like is used. Urea-degrading bacteria and the like can be inactivated. As a result, the generation of odor can be suppressed.

Therefore, by sequentially performing these three photocatalyst spraying steps (S1), the light irradiation step (S2), and the cleaning step using the cleaning water mixed with peroxide, a seal made of mortar that is a porous member. 4 and urea 12 existing inside and on the surface of the joint 12 can be almost inactivated. As a result, ammonia (NH ₃ ) odor is not generated.

  Therefore, the deodorizing method which can suppress the odor generated from the odor generating part which consists of porous can be provided.

  As described above, the deodorization method according to the present embodiment includes the photocatalyst spraying step S1 for spraying the photocatalyst on the seal 4 and the joint 12 as the porous odor generating part, and the light irradiation for performing the light irradiation process on the spraying part of the photocatalyst. Step S2 and cleaning step S3 for cleaning using cleaning water mixed with peroxide are included in this order.

For example, in the vicinity of the urinal 3, urea (CO (NH ₂ ) ₂ ) contained in the scattered urine remains in the odor generating portion such as the joint 12 of the porous tile 11, the seal 4, and the like. In this odor generating part, urea decomposing bacteria and the like decompose this urea (CO (NH ₂ ) ₂ ) to generate ammonia (NH ₃ ). For this reason, the odor generating part is a source of generation of an odor of ammonia (NH ₃ ) due to organic pollutants such as urea-decomposing bacteria.

In order to deodorize such odors from the odor generating part, in the present embodiment, a photocatalyst spraying process (S1) for spraying a photocatalyst and a light irradiation process (S2) for performing a light irradiation process on the spraying part of the photocatalyst. And a cleaning step S3 for cleaning using cleaning water mixed with peroxide. Thereby, it is considered that urea-decomposing bacteria and the like in the porous and surface of the porous odor generating part can be inactivated, and generation of ammonia (NH ₃ ) gas can be suppressed.

  That is, urine penetrates from the surface of the porous portion toward the inside. The urine, urea decomposing bacteria, etc. that have soaked into the porous part can be inactivated in the photocatalyst spraying step S1 and the light irradiation step S2.

However, the surface of the porous part of the mortar such as the seal 4 and the joint 12 has a high urine concentration. Therefore, many urea decomposing bacteria etc. are cultured on the surface of the porous part. Here, cleaning with peroxide does not penetrate into the inside of the porous portion, but has an effect on the surface of the porous portion. As a result, it is considered that a high effect of suppressing odor appears by performing a cleaning process on the surface of the porous portion having a high ammonia (NH ₃ ) gas concentration using cleaning water mixed with peroxide.

  Therefore, the deodorizing method which can suppress the odor generated from the odor generating part which consists of porous can be provided.

  Moreover, the deodorizing method in this Embodiment uses a visible light response type photocatalyst in a photocatalyst dispersion | spreading process (S1), and performs a light irradiation process using visible light in a light irradiation process (S2).

  That is, the photocatalyst includes a visible light responsive photocatalyst and an ultraviolet light responsive photocatalyst. Here, in the light irradiation step (S2), it is preferable to use a light source having as high emission intensity as possible.

  However, the light emission intensity of the ultraviolet light source is smaller than that of the visible light source. Moreover, when considering applying the deodorizing method of the present embodiment to a public toilet or the like, it is difficult to take a structure that seals ultraviolet light. Therefore, as a practical problem, it is more convenient to use visible light so as to use a light source with high emission intensity in the light irradiation step, and also to use a visible light responsive photocatalyst as the photocatalyst.

  Moreover, the deodorizing method in this Embodiment performs a light irradiation process using the light source containing light with a wavelength of 400-480 nm in a light irradiation process (S2).

  As a result, a blue LED that can output visible light having a wavelength of 400 to 480 nm with high emission intensity can be used, and an easily available blue LED can be used.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIG. The configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

In the deodorization method of the first embodiment, the photocatalyst spraying step is first performed. However, in this embodiment, ozone (O ₃ ) or hydrogen peroxide (H ₂ O ₂ ) or the like is used before the photocatalyst spraying step. The difference is that the pre-cleaning step is performed using cleaning water mixed with oxide.

  The deodorization method of this Embodiment is demonstrated based on FIG. FIG. 3 is a flowchart showing the deodorizing method of the present embodiment.

As shown in FIG. 3, the deodorization method of the present embodiment is preliminarily performed using a peroxide such as ozone (O ₃ ) or hydrogen peroxide (H ₂ O ₂ ) before the photocatalyst spraying step (S1). A cleaning process is performed (S0). Thereafter, a photocatalyst spraying process for spraying the photocatalyst is performed (S1), and then a light irradiation process for performing a light irradiation process on the photocatalyst spraying portion for a certain time, for example, 2 hours is performed (S2). Further, after the light irradiation step, the cleaning step is performed within 48 hours, which is a fixed time (S3).

  As described above, the deodorization method according to the present embodiment uses the pre-cleaning step (S0) in which the cleaning is performed using the cleaning water in which the peroxide is mixed in the porous odor generating part before the photocatalyst spraying step (S1). )including.

  That is, in the odor generating part made of a porous material such as mortar, as described above, urea-decomposing bacteria that decompose urine exist in the mortar and on the mortar surface. Therefore, in the case where the photocatalyst spraying step (S1) and the light irradiation step (S2) are directly performed on the odor generating part, it is necessary to sufficiently inactivate ureolytic bacteria and the like unless the light irradiation time is lengthened. I can't.

  Therefore, in the present embodiment, prior to the photocatalyst spraying step (S1), a pre-cleaning step (S0) is performed in which cleaning is performed using cleaning water in which peroxide is mixed in the porous odor generating part.

  Thereby, urea-decomposing bacteria having a high concentration on the surface of the porous portion are washed using washing water mixed with a peroxide having a high inactivation effect. As a result, it is possible to reduce the necessary inactivation amount in the photocatalyst spraying step (S1) and the light irradiation step (S2), and to shorten the irradiation time in the light irradiation step (S2). it can.

  Specifically, in Embodiment 1, the light irradiation time of the light irradiation process is set to 20 hours, for example, but in this embodiment, the light irradiation time of the light irradiation process can be shortened to, for example, 2 hours.

[Embodiment 3]
The following will describe still another embodiment of the present invention. The configurations other than those described in the present embodiment are the same as those in the first embodiment and the second embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of Embodiment 1 and Embodiment 2 are given the same reference numerals, and explanation thereof is omitted.

  In the deodorizing method of the first embodiment and the second embodiment, the cleaning process is performed immediately after the light irradiation process. In the present embodiment, it will be described how long the cleaning process can be performed after the light irradiation process.

  In the deodorizing method of the present embodiment, the cleaning process is performed within 48 hours after the light irradiation process. Thereby, it became clear by the verification experiment 3 mentioned later that an odor can be suppressed.

  Thus, in the deodorization method in this Embodiment, the washing | cleaning process (S3) after a light irradiation process (S2) is performed within 48 hours after a light irradiation process.

  That is, a cleaning step (S3) in which the photocatalyst spraying step (S1) and the light irradiation step (S2) are performed on the porous odor generating part, and then cleaning is performed using cleaning water mixed with peroxide. When the cleaning process (S3) is performed for a long time after the light irradiation process (S2), the urea-decomposing bacteria of the porous odor generating part grow again and the cleaning process is performed. In the step (S3), it cannot be sufficiently inactivated.

  Therefore, in the present embodiment, the cleaning step (S3) after the light irradiation step (S2) is performed within 48 hours after the light irradiation step (S2).

  As a result, even if urea-decomposing bacteria and the like in the porous odor generating part grow, excessive growth of the urea-decomposing bacteria and the like is suppressed in the cleaning step (S3) and generated from the porous odor generating part. Odor can be suppressed.

[Embodiment 4]
The following will describe still another embodiment of the present invention. The configurations other than those described in the present embodiment are the same as those in the first to third embodiments. For convenience of explanation, members having the same functions as those shown in the drawings of Embodiment 1 and Embodiment 2 are given the same reference numerals, and explanation thereof is omitted.

  In the deodorizing method of Embodiments 1 to 3, the cleaning step (S3) may be performed once. In the present embodiment, after the photocatalyst spraying step (S1) and the light irradiation step (S2), the cleaning step includes a cleaning step (S3) using cleaning water mixed with peroxide and a second urine spraying. The difference is repeated.

  That is, in the actual toilet 1, after the photocatalyst spraying step (S1) and the light irradiation step (S2) in the first embodiment, after the completion of the cleaning step (S3) using the cleaning water mixed with peroxide. The urine scattering or direct dripping on the scattering / dropping portion 13 on the floor surface 10 again due to the use of the toilet 1 occurs.

In this case, if left for a long time, urea-decomposing bacteria and the like exist again in the seal 4 and the joint 12 to generate ammonia (NH ₃ ) gas.

  In this case, it is costly to perform the deodorizing process of the first embodiment or the second embodiment again.

  Therefore, in the present embodiment, after the end of the cleaning step (S3), when the urine is scattered or dropped directly on the floor 10 by the use of the toilet 1 again, A cleaning step (S3) using cleaning water mixed with peroxide again in time is performed. Then, the scattering or direct dripping of urine again and the cleaning step (S3) using the cleaning water mixed with the peroxide within a predetermined time are repeated.

  It has been confirmed that the predetermined time is preferably within 48 hours according to the verification experiment 3 described later.

  Thus, as a deodorizing method, the photocatalyst spraying step (S1), the light irradiation step (S2), and the cleaning step (S3) using the cleaning water mixed with peroxide are not always performed, but within a certain time. Since the generation of odor can be suppressed only by repeating the cleaning step (S3) using the cleaning water in which the peroxide is mixed, cost reduction can be achieved during the deodorizing treatment.

  That is, in order to deodorize the odor from the odor generating unit, a photocatalyst spraying step (S1) for spraying a photocatalyst, a light irradiation step (S2) for performing a light irradiation process on the photocatalyst spraying portion, and a peroxide are mixed. And a washing step (S3) using the washing water. Thereby, it is considered that the urea-decomposing bacteria inside and on the surface of the porous odor generating part can be inactivated.

However, when urine is scattered again to the porous odor generating part, the odor is generated again as time passes. The reason for this is that generation of ammonia (NH ₃ ) gas requires urine and urea-decomposing bacteria, but an environment in which urea-decomposing bacteria and the like are cultivated by re-scattering urine. .

Therefore, in the present embodiment, a cleaning process using a peroxide having an inactivating effect is performed within 48 hours, and thereafter the cleaning process within 48 hours is repeated. As a result, it is possible to inactivate urea-decomposing bacteria and continue to suppress the generation of ammonia (NH ₃ ) gas.

  In the present embodiment, after the photocatalyst spraying step (S1) and the light irradiation step (S2) in the first embodiment, after the cleaning step (S3) using the cleaning water mixed with peroxide is completed. The repetition of the urine scattering or direct dripping and the washing step (S3) using the washing water mixed with the peroxide within a predetermined time has been described.

  However, in the present embodiment, the present invention is not necessarily limited to this. After the pre-cleaning step (S0), the photocatalyst spraying step (S1), and the light irradiation step (S2) in the second embodiment, peroxide is mixed. After the completion of the washing step (S3) using washing water, it is also applied to the repetition of the urine scattering or direct dripping and the washing step (S3) using washing water mixed with peroxide within a predetermined time. it can.

  As described above, the deodorization method of the present embodiment includes the photocatalyst spraying step (S1) for spraying the photocatalyst on the porous odor generating portion, and the light irradiation step (S2) for performing the light irradiation treatment on the photocatalyst spraying portion. And a cleaning step (S3) of cleaning using cleaning water mixed with peroxide in this order. Thereafter, the cleaning step (S3) of cleaning with the cleaning water mixed with peroxide is repeated within 48 hours.

  In addition, the deodorization method of the present embodiment includes a pre-cleaning step (S0) for cleaning the porous odor generating part using cleaning water mixed with peroxide, and a photocatalyst spraying step for spraying a photocatalyst. (S1), a light irradiation step (S2) for performing a light irradiation process on the photocatalyst spraying portion, and a cleaning step (S3) for cleaning with cleaning water mixed with peroxide are included in this order. Thereafter, the cleaning step (S3) of cleaning with the cleaning water mixed with peroxide is repeated within 48 hours.

  Thereby, even if odor generating factors such as urine spraying again occur after the first washing step (S3), it is possible to continue to suppress the generation of odor while reducing the cost.

  Moreover, in the deodorizing method in this Embodiment, the washing | cleaning process (S3) after a light irradiation process (S2) is repeatedly performed within 48 hours.

  That is, when the photocatalyst spraying step (S1), the light irradiation step (S2), and the washing step (S3) are performed on the porous odor generating part, and then urine is supplied, 48 hours have passed. In such a case, the urea-decomposing bacteria or the like in the porous odor generating portion grow again, and cannot be sufficiently inactivated in the cleaning step (S3).

  Therefore, in this embodiment, the repeated cleaning step (S3) is performed within 48 hours each time.

  As a result, even if urea-decomposing bacteria and the like in the porous odor generating part grow, excessive growth of the urea-decomposing bacteria and the like is suppressed in the cleaning step (S3) and generated from the porous odor generating part. Odor control can be continued.

[Verification experiment 1]
In this verification experiment 1, a verification experiment for the deodorization method of the first embodiment will be described.

  In the present embodiment, the purpose is to suppress odors from the odor generating part of the toilet 1, but in the verification experiment, as a preliminary examination of the implementation in the actual toilet 1, in the simple evaluation model 20 shown in FIG. A deodorization evaluation experiment was conducted.

  As shown in FIG. 4, the simplified evaluation model 20 includes a petri dish 23 in an airtight container 22 having a gas detection tube measurement port 21 in the upper part, and the joint 12 and the seal 4 that are sources of odor in the petri dish 23. The test piece 24 is made of a mortar material simulating the above.

  A method for producing the test piece 24 which is an odor generation source used in the deodorization evaluation experiment is as follows.

  First, the test piece 24 made of mortar material is separated into 5 g pieces, and the separated test piece 24 is discharged from the body and immersed in urine for 30 minutes at room temperature. Next, after inactivating urine, urea-decomposing bacteria collected in the toilet were added, and bacteria were cultured in a room temperature environment for 2 hours.

  And as deodorant evaluation, it performed about Example 1, the comparative example 1, and the comparative example 2 of the processing content shown in Table 1. FIG.

As shown in Table 1, in Example 1, after spraying tungsten oxide (WO ₃ ), which is a visible light responsive photocatalyst, as a photocatalyst spraying step on the prepared test piece 24, a blue LED is used as a light irradiation step. The sample was irradiated with visible light having a peak wavelength of 450 nm at an emission intensity of 7 mW / cm ^{2 for} 20 hours. Thereafter, urine was sprayed again and left in a room temperature environment for 30 minutes. Subsequently, the test piece 24 was treated with running water for 2 minutes using ozone (O ₃ ) water having a concentration of 2.5 ppm as a cleaning step.

  In addition, as a comparison, the photocatalyst spraying step, the light irradiation step, the second urine spraying, and the standing for 30 minutes are performed under the same conditions as in Example 1, and the comparative example 1 in which the subsequent cleaning step is not performed and tap water as the cleaning step. It performed about the comparative example 2 which used the flowing water process for 2 minutes.

As an evaluation experiment method, as shown in FIG. 4, each test piece 24 after the photocatalyst spraying step, the light irradiation step, the urine spraying again and standing for 30 minutes and the washing step is placed on the petri dish 23, and each volume is 5 L. The sealed container 22 was individually sealed. The concentration of ammonia (NH ₃ ) generated by the urea-decomposing bacteria cultured in the test piece 24 in the sealed container 22 between 30 minutes after urine spraying and 20 hours after the washing step. Was evaluated as the amount of odor generated. Thereafter, urine spraying, standing for 30 minutes, washing step, standing for 20 hours and measurement were repeated to evaluate the method for suppressing odor generation.

As an odor concentration measurement method, an ammonia (NH ₃ ) gas concentration was measured by connecting an ammonia (NH ₃ ) gas detection tube to the gas detection tube measurement port 21 of the sealed container 22.

The result is shown in FIG. In FIG. 5, the ammonia (NH ₃ ) gas concentration is greatly reduced once after 20 hours, after 40 hours and after 60 hours. This is because the test piece 24 is once taken out from the sealed container 22 after measuring the ammonia (NH ₃ ) gas concentration at the timing of 20 hours, 40 hours and 60 hours later. Then, after the urine is resprayed in the removed state and the washing process is performed, the test piece 24 is put into the sealed container 22, so that the ammonia (NH ₃ ) gas concentration in the sealed container 22 once becomes zero. This is because.

As shown in FIG. 5, when there is no cleaning process of Comparative Example 1 and when the cleaning process of Comparative Example 2 is performed with tap water, urine is sprayed and ammonia (NH ₃ ) It can be seen that the gas concentration is greatly increased and there is no effect of suppressing odor generation.

On the other hand, as shown in Example 1, when the washing process was performed with ozone (O ₃ ) water, the ammonia (NH ₃ ) gas concentration was large even when urine was sprayed and left for 20 hours. It turns out that it does not increase and maintains a low value.

The reason for this is that urine and urea-decomposing bacteria are required for the generation of ammonia (NH ₃ ) gas, but by respreading urine, an environment in which urea-decomposing bacteria and the like are cultured can be created. It is considered that the generation of ammonia (NH ₃ ) gas can be suppressed by inactivating urea-decomposing bacteria and the like by performing a cleaning step with ozone (O ₃ ) water having an inactivating effect. Moreover, since urine soaks inward from the surface of the porous portion, the concentration of the surface of the porous portion is high. Therefore, many urea decomposing bacteria etc. are cultured on the surface of the porous part. Ozone (O ₃ ) water does not penetrate to the inside of the porous part, but has an effect on the surface of the porous part, so the surface of the porous part having a high concentration is washed with ozone (O ₃ ) water. Therefore, it is considered that a high effect appears.

[Verification experiment 2]
In this verification experiment 2, a verification experiment regarding the deodorization method for performing the preliminary cleaning process of the second embodiment will be described. In addition, since the preparation method of the test piece 24 which is the simple evaluation model 20 of a verification experiment and the odor generation source used for a deodorization evaluation experiment is the same as the verification experiment 1 mentioned above, the description is abbreviate | omitted.

  In the verification experiment 2, the deodorization evaluation was performed on Example 2, Example 3, Comparative Example 3, and Comparative Example 4 having the processing contents shown in Table 2. These Example 2, Example 3, Comparative Example 3 and Comparative Example 4 are different from each other in the content of the pre-cleaning process and the standing time after the cleaning process. In the verification experiment 1, the light irradiation time in the light irradiation process was 20 hours, whereas in the verification experiment 2, the light irradiation time in the light irradiation process was shortened to 2 hours. ing.

That is, as shown in Table 2, in Example 2, the prepared test piece 24 is first subjected to a pre-cleaning process in which flowing water is treated for 2 minutes using ozone (O ₃ ) water having a concentration of 2.5 ppm.

On the other hand, in Example 3, a pre-cleaning process is first performed on the produced test piece 24 by flowing water for 2 minutes using 10% hydrogen peroxide (H ₂ O ₂ ) water.

  For Comparative Example 3 and Comparative Example 4, the pre-cleaning process is not performed.

Then, after spraying tungsten oxide (WO ₃ ), which is a visible light responsive photocatalyst, as a photocatalyst spraying step for all of Example 2, Example 3, Comparative Example 3 and Comparative Example 4, as a light irradiation step Visible light having a peak wavelength of 450 nm was irradiated with a blue LED at an emission intensity of 7 mW / cm ^{2 for} 2 hours. Then, urine was sprayed again and left in a room temperature environment for 30 minutes.

Thereafter, in Example 2, Example 3, and Comparative Example 3, the test piece 24 was treated with running water for 2 minutes using ozone (O ₃ ) water having a concentration of 2.5 ppm as a cleaning step. In Comparative Example 3, the cleaning process is not performed.

Thereafter, with respect to all of Example 2, Example 3, Comparative Example 3 and Comparative Example 4, each test piece 24 was put into each sealed container 22 and allowed to stand for 20 hours, and then the ammonia (NH ₃ ) gas concentration was measured. went.

As a result, each ammonia (NH ₃ ) gas concentration was 3.5 ppm in Example 2, 3 ppm in Example 3, 18 ppm in Comparative Example 3, and 30 ppm in Comparative Example 4, as shown in Table 2. .

As a result, the light in the light irradiation step is performed by performing the pre-cleaning step using ozone (O ₃ ) water or hydrogen peroxide (H ₂ O ₂ ) water having an inactivation effect before the photocatalyst spraying step. It can be seen that even if the irradiation time is shortened to 2 hours, generation of ammonia (NH ₃ ) gas after being left for 20 hours can be suppressed.

This is because the concentration of urea-decomposing bacteria and the like cultured in the porous body decreases from the surface toward the inside, and the amount of urea-decomposing bacteria and the like on the surface of the porous part is the largest. Although ozone (O ₃ ) water or hydrogen peroxide (H ₂ O ₂ ) water has a high deactivation effect, it does not penetrate into the inside, so it is effective only in the vicinity of the surface and has a low effect on the inside.

On the other hand, although the deactivation effect of the photocatalyst penetrates to the inside, the deactivation effect is not as high as that of ozone (O ₃ ) water or hydrogen peroxide (H ₂ O ₂ ) water. The activation effect is not sufficient.

  Therefore, the urea-decomposing bacteria having a high concentration on the surface of the porous part is treated with a peroxide having a high inactivation effect. Thereby, the required inactivation amount in the photocatalyst spraying step and the light irradiation step can be reduced. This means that the light irradiation time can be shortened.

  That is, in Example 1 of the verification experiment 1 described above, irradiation is performed for 20 hours as the light irradiation process, whereas in Examples 2 and 3 of the verification experiment 2, the light irradiation process is performed for 2 hours. Is sufficient. Here, when considering deodorizing treatment in an actual public toilet or the like, it is difficult to perform LED irradiation for 20 hours in view of the presence of a user. Therefore, it is a great advantage that the light irradiation time can be shortened.

[Verification Experiment 3]
In this verification experiment 3, the odor generation suppression effect was evaluated using the actual toilet 1 instead of the simple evaluation model 20 described above.

During the experiment, when the ammonia (NH ₃ ) gas concentration around the urinal 3 of the toilet 1 was measured, the seal 4 shown in FIG. 1 had the highest ammonia (NH ₃ ) gas concentration. For this reason, the process of Example 4, Example 5, Comparative Example 5 and Comparative Example 6 shown in Table 3 was performed on the seal 4.

First, in all of Example 4, Example 5, Comparative Example 5 and Comparative Example 6, the seal 4 was subjected to running water treatment using ozone (O ₃ ) water having a concentration of 2.5 ppm as a preliminary cleaning step. Then, after spraying tungsten oxide (WO ₃ ), which is a visible light responsive photocatalyst, as a photocatalyst spraying step, the visible light having a peak wavelength of 450 nm is emitted using a blue LED as a light irradiation step. Irradiation was performed for 2 hours at an emission intensity of 7 mW / cm ² . Further, 24 hours later, the ammonia (NH ₃ ) gas concentration was measured using a gas detection tube at the location of the seal 4.

After measurement of the ammonia (NH ₃ ) gas concentration, the following different treatments were performed in Example 4, Example 5, Comparative Example 5 and Comparative Example 6, respectively.

First, in Example 4, immediately after the measurement, a cleaning process using ozone (O ₃ ) water having a concentration of 2.5 ppm was performed, and after standing for 24 hours, the ammonia (NH ₃ ) gas concentration was measured. This process was repeated every 24 hours.

Next, in Example 5, a cleaning process using ozone (O ₃ ) water having a concentration of 2.5 ppm was performed immediately after the measurement, and after standing for 48 hours, the ammonia (NH ₃ ) gas concentration was measured. This process was repeated every 48 hours.

Subsequently, in Comparative Example 5, a cleaning process using ozone (O ₃ ) water having a concentration of 2.5 ppm was performed immediately after the measurement, and the ammonia (NH ₃ ) gas concentration was measured after being left for 72 hours. This process was repeated every 72 hours.

Finally, in Comparative Example 6, the cleaning step was not performed immediately after the measurement, and the ammonia (NH ₃ ) gas concentration was measured after being left for 24 hours. This process was repeated every 24 hours.

  As a result, the measurement result shown in FIG. 6 was obtained. FIG. 6 is a graph showing measurement results in the verification experiment 3.

That is, in Example 4 and Example 5 shown in FIG. 6, when the cleaning process using ozone (O ₃ ) water is performed every 24 hours or every 48 hours, the ammonia (NH ₃ ) gas concentration increases. It can be seen that a low ammonia (NH ₃ ) gas concentration of 10 ppm or less can be maintained.

However, as shown in FIG. 6, in Comparative Example 5 in which the cleaning process using ozone (O ₃ ) water was performed every 72 hours, the ammonia (NH ₃ ) gas concentration increased and the cleaning process was not performed. It was found that an ammonia (NH ₃ ) gas concentration substantially equal to that in Example 6 was reached.

[Verification Experiment 4]
In this verification experiment 4, an attempt was made to perform the same evaluation as in the verification experiment 3 by using a photocatalyst for ultraviolet light instead of a visible light responsive photocatalyst. Therefore, in the light irradiation process, ultraviolet light having a peak wavelength of 365 nm was changed to a light emission intensity of 0.5 mW / cm ² using a blue LED.

That is, some visible light LEDs have a high emission intensity of 7 mW / cm ² . However, in the LED for ultraviolet light, since there is not yet a high emission intensity, the irradiation intensity can be prepared only under the condition of low emission intensity.

  Moreover, when using LED for ultraviolet light, since the ultraviolet-ray is irradiated, it is preferable to take the light irradiation method which does not leak light outside. In particular, in the irradiation with the toilet 1 that is expected to be used by the public, a structure that prevents ultraviolet rays from leaking outside is essential.

  Therefore, in this verification experiment 4, preparations were also made for a verification experiment. However, since the irradiation location varies depending on the shape of the toilet 1, it is difficult to prepare a structure in which ultraviolet rays do not leak. As a result, it turned out that it was difficult to irradiate with the toilet 1 which is expected to be used by the public.

  That is, the shape of the toilet 1 differs depending on the place where it is installed. In addition, it was found that it is difficult to take a structure that seals ultraviolet light in situations where public use is expected, and it is difficult to use a photocatalyst that supports ultraviolet light due to safety issues.

[Summary]
The deodorization method in aspect 1 of the present invention includes a photocatalyst spraying step S1 for spraying a photocatalyst on a porous odor generating part (seal 4 and joint 12), and a light irradiation process S2 for performing a light irradiation process on the photocatalyst spraying part. And a cleaning step S3 for cleaning using cleaning water mixed with peroxide in this order.

For example, in the vicinity of a toilet bowl, urea (CO (NH ₂ ) ₂ ) contained in the scattered urine remains in the odor generating part such as a tile joint or a seal made of a porous material that is a scattered part. In this odor generating part, urea decomposing bacteria and the like decompose this urea (CO (NH ₂ ) ₂ ) to generate ammonia (NH ₃ ). For this reason, the odor generating part is a source of generation of an odor of ammonia (NH ₃ ) due to organic pollutants such as urea-decomposing bacteria.

In order to deodorize such odor from the odor generating part, in the present invention, a photocatalyst spraying process for spraying a photocatalyst and a light irradiation process for performing a light irradiation process on the photocatalyst spraying part are performed. Thereby, it is considered that urea-decomposing bacteria in the porous region in the porous odor generating part can be inactivated, and generation of ammonia (NH ₃ ) gas can be suppressed.

  That is, urine penetrates from the surface of the porous portion toward the inside. Urine, urea-decomposing bacteria, etc. that have soaked into the porous part can be inactivated in the photocatalyst spraying step and the light irradiation step.

However, the surface of the porous part of the mortar such as the seal and joint has a high urine concentration. Therefore, many urea decomposing bacteria etc. are cultured on the surface of the porous part. Here, cleaning with peroxide does not penetrate into the inside of the porous portion, but has an effect on the surface of the porous portion. As a result, it is considered that a high effect of suppressing odor appears by performing a cleaning process on the surface of the porous portion having a high ammonia (NH ₃ ) gas concentration using cleaning water mixed with peroxide.

  Therefore, the deodorizing method which can suppress the odor generated from the odor generating part which consists of porous can be provided.

  The deodorization method in aspect 2 of the present invention is the deodorization method in aspect 1, wherein the photocatalyst spraying step S1 uses a visible light responsive photocatalyst, and the light irradiation step S2 uses visible light to emit the light. It is preferable to carry out the treatment.

  That is, the photocatalyst includes a visible light responsive photocatalyst and an ultraviolet light responsive photocatalyst. Here, it is preferable to use a light source with as high emission intensity as possible in the light irradiation step.

  However, the light emission intensity of the ultraviolet light source is smaller than that of the visible light source. Moreover, when considering applying the deodorizing method of the present invention to a public toilet or the like, it is difficult to adopt a structure that seals ultraviolet light.

  Therefore, as a practical problem, it is more convenient to use visible light so as to use a light source with high emission intensity in the light irradiation step, and also to use a visible light responsive photocatalyst as the photocatalyst.

  In the deodorization method according to aspect 3 of the present invention, in the deodorization method according to aspect 1 or 2, it is preferable that the light irradiation process is performed using a light source including light having a wavelength of 400 to 480 nm in the light irradiation step S2.

  As a result, a blue LED that can output visible light having a wavelength of 400 to 480 nm with high emission intensity can be used, and an easily available blue LED can be used.

  The deodorization method according to aspect 4 of the present invention is the deodorization method according to aspects 1, 2, or 3, using washing water in which a peroxide is mixed in a porous odor generating part before the photocatalyst spraying step S1. It is preferable to include a pre-cleaning step S0 for cleaning.

  That is, in the odor generating part made of a porous material such as mortar, as described above, urea-decomposing bacteria that decompose urine exist in the mortar and on the mortar surface. Therefore, in the case where the photocatalyst spraying step and the light irradiation step are directly performed on the odor generating part, ureolytic bacteria and the like cannot be sufficiently inactivated unless the light irradiation time is increased.

  Therefore, in the present invention, prior to the photocatalyst spraying step, a pre-cleaning step is performed in which cleaning is performed using cleaning water in which peroxide is mixed in the porous odor generating part.

  Thereby, urea-decomposing bacteria having a high concentration on the surface of the porous portion are washed using washing water mixed with a peroxide having a high inactivation effect. As a result, the necessary inactivation amount in the photocatalyst spraying step and the light irradiation step can be reduced, and the irradiation time in the light irradiation step can be shortened.

  In the deodorization method in aspect 5 of the present invention, in the deodorization method in aspect 4, it is preferable that the washing step S3 after the light irradiation step S2 is performed within 48 hours after the light irradiation step S2.

  That is, when the photocatalyst spraying step and the light irradiation step are performed on the porous odor generating part, and then the cleaning step is performed using the cleaning water mixed with the peroxide, the cleaning step is performed. When a long time has passed after the light irradiation process, the urea-decomposing bacteria and the like in the porous odor generating part grow again and cannot be sufficiently inactivated in the cleaning process.

  Therefore, in the present invention, the cleaning step after the light irradiation step is performed within 48 hours after the light irradiation step.

  As a result, even if urea-decomposing bacteria etc. in the porous odor generating part grow, excessive growth of urea decomposing bacteria etc. is suppressed in the washing process, and odor generated from the porous odor generating part is suppressed. Can last.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the technical means disclosed in different embodiments can be appropriately combined. Such embodiments are also included in the technical scope of the present invention.

  The present invention can be applied to deodorizing odors generated in, for example, household toilets or public toilets such as stations, vehicles, hotels, restaurants, schools, and hospitals. Further, the present invention is not limited to toilets such as household toilets and public toilets, and can be applied to odor control of odors such as sewage treatment plants, incineration plants, and waste storage facilities.

DESCRIPTION OF SYMBOLS 1 Toilet 2 Wall surface 3 Urinal 4 Seal 10 Floor surface 11 Tile 12 Joint 13 Spattering / dropping part 14 Light irradiation area 20 Simple evaluation model 21 Gas detection tube measurement port 22 Sealed container 23 Petri dish 24 Test piece

Claims (5)

A photocatalyst spraying step of spraying a photocatalyst on a porous odor generating part;
A light irradiation step of performing a light irradiation process on the dispersion portion of the photocatalyst;
A deodorizing method comprising: a cleaning step of cleaning with cleaning water mixed with peroxide in this order. In the photocatalyst spraying step, a visible light responsive photocatalyst is used,
The deodorization method according to claim 1, wherein in the light irradiation step, the light irradiation treatment is performed using visible light.   3. The deodorization method according to claim 1, wherein in the light irradiation step, the light irradiation treatment is performed using a light source including light having a wavelength of 400 to 480 nm.   4. The deodorization method according to claim 1, further comprising a pre-cleaning step of cleaning with a cleaning water in which a peroxide is mixed in a porous odor generating part before the photocatalyst spraying step. Method.   The deodorizing method according to claim 4, wherein the cleaning step after the light irradiation step is performed within 48 hours after the light irradiation step.

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