JPH10263391A - Odor component-containing gas deodorant, deodorizing method using the same, and method for regenerating the deodorant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a deodorant for combined malodors, having a practical effect in spite of one kind by subjecting a clay mineral consisting of silica, alumina, diiron trioxide, magnesia and water of crystallization in a specified ratio and having a laminar structure to 1st-stage hydrothermal synthesis at a specified temp. for a specified time and 2nd-stage hydrothermal synthesis at a specified temp. for a specified time. SOLUTION: A clay mineral consisting of, by mol, 20-70% SiO2 , 5-20% Al2 O3 , 0-10% Fe2 O3 , 0-10% MgO and 5-20% H2 O and having a laminar structure as the basic skeleton structure and a microcrystalline grain form is subjected to 1st-stage hydrothermal synthesis at 50-100 deg.C for 1-5 hr and 2nd-stage hydrothermal synthesis at 150-250 deg.C for 1-3 hr to enhance the deodorizing performance of the raw mineral. The resultant clay mineral microcrystals are used as the principal component of a deodorant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to air containing high concentration and combined odor in facilities that generally generate odors, such as garbage incineration plants, sewage treatment plants, livestock breeding plants, fertilizer production plants, and fermented food production processing plants. The present invention relates to a deodorant for deodorizing gas and exhaust gas, a deodorizing method using the deodorant, and a method for regenerating the deodorant.

[0002]

2. Description of the Related Art Activated carbon and synthetic zeolites conventionally used as adsorbents in sewage treatment plants and garbage incineration plants are:
The adsorption performance for complex odor is not yet satisfactory in practical use. For example, activated carbon requires various chemicals to be impregnated according to the basicity and acidity of odor gas such as ammonia, hydrogen sulfide, butyric acid, and valeric acid. It costs. In addition, the adsorption performance of zeolite is apt to deteriorate when the water content in the gas is large.

[0003]

DISCLOSURE OF THE INVENTION The present invention relates to an odor component in an odor-containing gas, particularly to a complex odor gas ranging from basic to acidic, such as ammonia, mercaptan, methyl sulfide, hydrogen sulfide, trimethylamine, butyric acid, and valeric acid. It is an object of the present invention to provide a deodorizing agent for a complex odor which has one kind of practical effect, a deodorizing method using the deodorizing agent, and a regeneration treatment method after using the deodorizing agent.

[0004]

As a deodorant for removing odorous components, in claim 1, the composition ratio is silica (SiO 2).
₂ ) 20-70 mol%, alumina (Al ₂ O ₃ ) 5-2
0 mol%, diiron trioxide (Fe ₂ O ₃ ) 0-10 mol%,
Magnesia (MgO) 0-15 mol%, water of crystallization (H
₂ O) 5-20 the layer structure clay mineral is a mol% 50 ° C. -
After the first-stage hydrothermal synthesis at a temperature of 100 ° C. for 1-5 hours,
Further, the present invention provides an odor-containing gas deodorizing agent mainly composed of clay mineral microcrystals obtained by hydrothermal synthesis at 150 ° C. to 250 ° C. for 1-3 hours.

According to the second aspect of the present invention, the clay mineral after the hydrothermal synthesis is further subjected to an acid treatment to obtain an acid strength function (H
₀ ) is -3.0 ≦ H ₀ ≦ −0.5
The present invention provides a deodorant containing clay mineral microcrystals as a main component and adjusted to the range described above.

In a third aspect of the present invention, there is provided the clay mineral microcrystal according to the first or second aspect, wherein the group comprises a 7A group, a 8 group, a 1B group, or a platinum group element of the fourth period of the long period type periodic table. (Ie, Mn, Fe, Co, Ni, Cu, or P
d, Pt, etc.) The present invention provides a deodorant mainly composed of clay mineral microcrystals supporting at least one metal or metal oxide selected from the group consisting of:

According to a fourth aspect of the present invention, the odor-containing gas is mixed with the deodorant of the first, second or third aspect at -40.degree.
At a gas pressure of 1-10 kg / cm ² ,
Provided is a method for deodorizing an odor-containing gas, wherein the contact is performed under the conditions of an HSV of 1,000 to 95,000 h ^-1 .

Further, in the invention according to claim 5, the deodorant according to claim 3 used in the deodorizing treatment is used at a temperature of 100 ° C. to 500 ° C.
Provided is a method for regenerating a deodorant, which comprises performing a heat treatment.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The raw material mineral used in the present invention has a composition ratio of SiO ₂ : 20-70 mol%, Al ₂ O ₃ : 5-
20 mol%, Fe ₂ O _3: 0-10 mol%, MgO:
A clay mineral having 0 to 10 mol% and H ₂ O: 5 to 20 mol%. The clay mineral has a layer structure as a basic skeleton structure and has a microcrystalline particle form. Specific examples include natural montmorillonite and bentonite, purified products thereof, and synthetic products having the above composition ratios. In the invention of claim 1, the raw material mineral is subjected to a two-stage hydrothermal synthesis treatment to enhance the deodorizing performance. That is, the layered clay mineral is subjected to the first-stage hydrothermal synthesis at a temperature of 50 ° C. to 100 ° C. for 1 to 5 hours by using a known method, and then further at 150 ° C. to 250 ° C.
Clay mineral microcrystals obtained by performing the second stage hydrothermal synthesis at 1-3 ° C. for 1-3 hours are used as the main component of the deodorant of the present invention. Usually, a mixture of the above-mentioned main component and the porosity imparting mineral is granulated by a conventional method such as extrusion molding and the like, and calcined to obtain a deodorant.

According to the second aspect of the present invention, the clay mineral microcrystals are acid-treated using a strong acid mineral acid such as sulfuric acid or hydrochloric acid, and the acidity of the mineral as a solid acid is firstly -4.0 ≦ H ₀ ≦ −
Adjust to the range of 2.0. As an example of the acid treatment, for example, concentrated sulfuric acid having a concentration of 40% is added to a clay mineral as a raw material in a weight ratio of 60%.
%, Stirred at 80-100 ° C for 2-4 hours, washed well with water and dried. Alternatively, hydrochloric acid having a concentration of 15-20% is added to the raw clay in an amount 2-3 times by weight, and the mixture is boiled and refluxed for 3-5 times.
After stirring for an hour, wash well with water and dry. Then, while measuring the acidity by, for example, an n-butylamine titration method, the stirring time is adjusted to adjust the acidity to a range of −3.0 ≦ H ₀ ≦ −0.5. An example of the composition thus prepared is synthetic frypontite (Mizukanite, manufactured by Mizusawa Chemical Industry Co., Ltd.).

According to the third aspect of the present invention, one or more elements of a specific group of so-called main transition metals, such as Mn, Cu, and Pt, are added to the clay mineral microcrystal according to the first or second aspect. A metal or metal oxide is supported thereon to form a deodorant. As the element to be supported, Mn, Fe, Co, Ni, Cu, Pd, and Pt are preferable, and Pt is particularly preferable. The supporting method is, for example, a method in which an aqueous solution of a water-soluble salt of the metal is mixed with the clay mineral microcrystal according to claim 1 or 2, and the mixture is molded, dried naturally or dried by heating at about 120 ° C., and then calcined. The binder obtained by adding a binder to the clay mineral microcrystals, granulating to an appropriate size, and sintering the pellets is immersed in the aqueous solution, and dried.
A method commonly used in the art, such as a firing method, is used. The deodorant of the present invention thus produced has an action of oxidatively decomposing odor components by heating at a high temperature.

According to a fourth aspect of the present invention, for example, the removing agent of the present invention is filled in a flow-type packed bed reactor having a heating means, preheated to a required temperature, and the odor-containing gas is cooled to a winter atmospheric temperature of, for example, -40. Temperature range of exhaust gas from garbage incineration plant to 100 ° C., gas pressure 1-10 kg / cm
GHSV 1,000-95,000, gas flow rate in the range of ²
By distributing under certain conditions in the range of 0h ^-1 ,
Contact with the deodorant. The lower the temperature at the time of contact, the better the deodorization, but it is not practical for the entire deodorization process to cool the exhaust gas to a temperature lower than the atmospheric temperature in winter, and the deodorization rate decreases at high temperatures, For example, it is not practical when the temperature is higher than the exhaust gas temperature of the offensive odor source, especially when the temperature is higher than the temperature of the exhaust gas containing saturated steam in the garbage incineration plant.

Next, regarding the gas flow rate, GHSV is 1,
When it is lower than 000 h ^-1 , the deodorizing efficiency per unit time is low, and when GHSV is higher than 95,000 h ^-1 , the contact between the odor component and the deodorant becomes insufficient, so that the deodorization rate decreases. However, neither is preferred.

Examples of the odor components in the present invention include components normally contained as complex odors in odor-containing gases of sewage treatment plants and garbage incineration plants, particularly ammonia, mercaptan, methyl sulfide, hydrogen sulfide, trimethylamine, butyric acid, and the like.
Components ranging from basic to acidic, such as valeric acid, are mentioned. In addition, thiols such as t-butyl mercaptan, thioethers such as dimethyl sulfide, carbonyl sulfide (COS), thiophene and the like are added as odorants for city gas. And the like.

[0015]

EXAMPLES The present invention will be described in more detail with reference to Examples, but it should not be construed that the invention is limited thereto. Here, "%" means% by weight unless otherwise specified. The deodorization rate was determined by flowing a gas containing various malodorous components through a fixed-bed flow reactor, performing a sensory test on the gas at the outlet of the reactor, and measuring the weight of each component collected by the deodorant until the strength reached 1. The value obtained by dividing by the weight of the original deodorant was converted to%.

[Deodorizing Agent Production Example 1] 0.2% of Pt was supported on a mizucanite manufactured by Mizusawa Chemical Industry Co., Ltd., which is a clay mineral microcrystal having an adjusted solid acidity, by a conventional salt solution impregnation method. Was obtained.

[Deodorizing Treatment Example 1] A tubular reactor was charged with 100 g of the above deodorizing agent, and air containing 50 ppm of ammonia and 30 ppm of hydrogen sulfide and having a dew point of 30 ° C. was purified by GHSV.
The mixture was circulated at 10,000 h ^-1 , and the outlet gas was subjected to a sensory test. The weight of each component collected by the deodorant until the strength reached 1 was measured. % By weight based on 100 g of the original deodorant
As a result, the collection amount of ammonia was 7% and the collection amount of hydrogen sulfide was 20%.

Comparative Example 1 The above tubular reactor was charged with 100 g of a commonly used activated carbon deodorant (trade name, granular Shirasagi), and the same gas as in Example 1 was allowed to flow under the same conditions. Collection amount 3%, hydrogen sulfide collection amount 10%
Met.

[Regeneration Treatment Example 1] The deodorant of the present invention after being used in Example 1 was charged into the reactor,
While flowing air at a speed of 10,000 GHSV, 35
By heating at 0 ° C., the odor component was oxidized and decomposed into H ₂ O, N ₂ , CO _{2 and the} like. Example 1 again with the regenerated deodorant
The deodorization treatment was performed as described above. This was repeated, and the deodorizing result of the deodorizing agent after the regeneration treatment was performed 10 times was 5% for the collection amount of ammonia and 17% for the collection amount of hydrogen sulfide.

[0020]

The deodorant of the present invention is characterized by the fact that the odor components in the odor-containing gas, particularly ammonia, mercaptan, methyl sulfide,
For complex odor gas containing components ranging from basic to acidic such as hydrogen sulfide, trimethylamine, butyric acid, valeric acid,
Since one type of deodorant has an effective deodorizing effect, it has high practical value against complex odors.

Since the deodorizing method of the present invention is carried out at the atmospheric temperature or at a temperature considerably lower than that of the prior art, the deteriorating agent does not deteriorate for a long time, for example, the active sites of the deodorizing agent are covered by the decomposed products of trace components. In addition, since it can be reproduced many times, it can withstand long-term use.

The deodorizing method of the present invention does not require an activation operation before use as in the prior art, so that it is simple and the deodorizing equipment can be easily restarted.

Claims (5)

[Claims] 1. A composition ratio of silica (SiO ₂ ) 20-70.
Mol%, of alumina (Al ₂ O ₃₎ 5-20 mol%, diiron trioxide (Fe ₂ O ₃₎ 0-10 mol%, magnesia (M
gO) The first-stage hydrothermal synthesis of a layered clay mineral having 0 to 15 mol% and H ₂ O of 5 to 20 mol% at a temperature of 50 ° C. to 100 ° C. for 1 to 5 hours, and then at 150 ° C. to 250 ° C. 1-3
An odor-containing gas deodorant composed mainly of clay mineral microcrystals obtained by second-stage hydrothermal synthesis. 2. The clay mineral after hydrothermal synthesis is further treated with an acid to adjust the solid acidity expressed by an acid strength function (H ₀ ) to a range of −3.0 ≦ H ₀ ≦ −0.5. 2. The deodorant according to claim 1, comprising a clay mineral microcrystal as a main component. 3. The clay mineral microcrystal according to claim 1 or 2, wherein the fourth period of the long period type periodic table has a 7A group, a 8 group, and a 1B group.
A deodorant containing, as a main component, clay mineral microcrystals carrying at least one or more metals or metal oxides selected from the group consisting of group III or platinum group elements. 4. An odor-containing gas comprising the deodorant according to claim 1, 2 or 3, and a gas pressure of 1-10 kg / cm ² and a GHSV of 1,000-9 at a temperature of -40 ° C.-100 ° C.
A method for deodorizing an odor-containing gas, wherein the odor-containing gas is contacted under a condition of 5,000 h ^-1 . 5. A method for regenerating a deodorant according to claim 3, wherein the deodorant is heated at a temperature of 100 ° C. to 500 ° C. after use in the deodorizing treatment.