JP2709264B2 - Deodorizing apparatus and method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the removal of harmful gases such as odors generated during the composting process in livestock farms and odors exhausted from establishments such as chemical factories.
More specifically, the present invention relates to a deodorizing apparatus and a method therefor which can be easily and efficiently used, and more specifically, to use a chemical material which is easy to handle and to effectively use the substances generated in the odor removing process. The present invention relates to a highly versatile deodorizing apparatus and method.

[0002]

2. Description of the Related Art In a modern society in which a mass consumer society has taken root, various chemical substances are produced and produced as by-products, and they want to benefit from a rich material civilization. On the other hand, environmental pollution on a global scale is required. In order to prevent such environmental pollution, regulations on automobile exhaust gas and CFCs and the establishment of a treaty on carbon dioxide emission control and domestic legislation are in progress.

[0003] Among them, the Odor Control Law has been enforced for a long time to prevent the inflow and diffusion of harmful substances (ammonia, hydrogen sulfide, trimethylamine, etc.) into the living environment.
With the increasing public interest in preventing odors from entering the living environment, substances subject to regulation have been added (lower fatty acids, etc.) due to the revision of the Enforcement Ordinance. If the regulated substance contained in the gas generated in the industry exceeds a certain standard at the boundary of the dwelling site, an order to improve the facility is to be issued.

[0004] For this reason, livestock farmers need to take measures to prevent odors such as ammonia and lower fatty acids generated in composting facilities from flowing into ordinary houses.
These treatments were performed using the following devices and means.

A method of adjusting the opening degree of a window from a place where odor is generated, such as a composting treatment facility, and gradually releasing the odor gas into the atmosphere to dilute the odor gas to a certain reference concentration or less ( Hereinafter, the infinite dilution method) has been widely used in terms of cost and simplicity.

[0006] Devices and methods for adsorbing odors generated in composting facilities and the like to soil and decomposing and removing the odors by microorganisms in the soil (hereinafter referred to as soil treatment devices and methods) have been employed.

[0007]

However, the above-mentioned conventional odor control device and method have various problems as described below.

[0008] That is, in the infinite dilution method, the time during which the odor is diluted to a certain concentration or less is a fluid thing that changes depending on the amount of the odor released per unit time, the air current, and the like. There is no telling whether the odor will be diluted below a certain standard concentration before the odor flows, and it is the odor of livestock farmers that adjusts the degree of opening of the windows, etc. Since stable control of the amount of release per hour is not possible, there has been a problem that it is not possible to reliably maintain the concentration below a certain reference level at the boundary of a house.

[0009] In today's world, where the distance between a house and a livestock farm is becoming smaller, and it is becoming more common for livestock farmers to surround a livestock farm, and the speed of consolidation is increasing, it is sufficient if the concentration is below a certain concentration for a long time. The probability that the odor would flow to a general house such as a private house without dilution was extremely high, and the above problem was particularly remarkable.

[0010] Further, in the process of releasing odor into the atmosphere, this is a passive solution that waits for the odor to be diluted below a certain reference concentration. Since the absolute amount of the substance does not change, even if it is naturally decomposed by sunlight or plants, its decomposition rate is slow, and the concentration of the chemical substance in the atmosphere increases, thus preventing air pollution. There was a problem that it was unfavorable in a strong shout.

Further, since the degree of opening of the windows is controlled by the odor of the livestock farmer, the amount of smell is inevitably increased, and the probability of harm to the health is greatly increased. However, there is a problem that the efficiency of the agricultural work is mentally reduced due to the unpleasant odor.

Next, in the soil treatment apparatus and method,
It is a biologically decomposable odor, and its decomposition rate is slow, so that a large amount of soil is required, which increases the installation area, and is expensive and uneconomical.

[0013] Further, since it is a biological decomposition, maintenance and management of the apparatus requires biological expertise, and it is very difficult and troublesome for general livestock farmers who do not have the expertise. There was a problem.

[0014] The present invention has been made in view of the above-mentioned circumstances, and it is easy, safe, and efficient to remove gas that is harmful to the living environment such as bad smells generated during the composting process in a livestock farm. It is intended to provide a deodorizing apparatus and a method therefor which can be carried out.

[0015]

In order to achieve the above-mentioned object, the present invention provides a first tank configured to bring a malodorous gas into gas-liquid contact with a sulfuric acid solution, and a porous tank mainly composed of calcium silicate. The present invention provides a deodorizing apparatus characterized in that a bad odor is removed by passing through a second tank configured to be in gas-liquid contact with a liquid circulating in contact with a substance.

Further, the present invention solves the above-mentioned problem by providing the above-mentioned deodorizing device, which is a first tank configured to circulate a sulfuric acid solution.

[0017] The present invention also provides the first tank or the second tank,
The object is attained by providing the deodorizing device, wherein a gas-liquid contact promoting member is provided.

Further, according to the present invention, the porous substance containing calcium silicate as a main component is selected from the group consisting of tobermorite, zonotolite, and C
The object is achieved by providing one or more of the above deodorizing devices selected from the group consisting of SH gel, fusiyadite, gyrolite, and hilleplandite.

Further, the present invention provides a first treatment in which a malodorous gas is brought into gas-liquid contact with a sulfuric acid solution, and a second treatment in which gas and liquid are brought into contact with a liquid circulating in contact with a porous substance containing calcium silicate as a main component. The above object is attained by providing a deodorizing method characterized in that the offensive odor is removed by performing the treatment of (1) and (2).

[0020]

In the deodorizer according to the present invention, the liquid or mist sulfuric acid solution in the first tank neutralizes basic components such as ammonia by gas-liquid contact with malodorous gas.
Absorb.

In the deodorizing apparatus according to the present invention, the liquid circulating in contact with the porous substance (tobermorite, zonotolite, CSH gel, etc.) containing calcium silicate as the main component in the second tank is subjected to gas-liquid contact with the malodorous gas. By doing
-Neutralizes and absorbs lower fatty acids such as butyric acid.

In the deodorizing device according to the present invention, the gas-liquid contact promoting member disposed in the first tank or the second tank contacts the malodorous gas with a sulfuric acid solution or a porous substance containing calcium silicate as a main component. By increasing the contact time and contact area with the circulating liquid, the efficiency of neutralizing and absorbing malodorous gas is increased.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a deodorizing apparatus and a deodorizing method according to the present invention will be described more specifically with reference to the drawings.

First, the deodorizing apparatus in this embodiment is shown in FIG.
As shown in FIG. 3, a first tank 11 configured to bring a malodorous gas into gas-liquid contact with a sulfuric acid solution, and a liquid circulating in contact with a porous substance 30 containing calcium silicate as a main component. The second tank 12 configured to be in liquid contact with the second tank 12 is configured to remove a bad smell.

In the deodorizing method of the present embodiment, the first treatment of bringing the malodorous gas into gas-liquid contact with a sulfuric acid solution and the liquid circulating in contact with the porous substance 30 containing calcium silicate as a main component are used. The odor is removed by performing the second process of bringing into contact with gas and liquid.

The first tank 11 and the second tank 12 are provided with a demister 14
And a blower 1 that sucks the odor into the first tank 11 and blows the odor to the first tank 11 via a vibration-proof duct 8. The second tank 12 is provided with an outlet 3 to which a demister 34 is attached so that the odor blown from the first tank 11 is discharged after the treatment.

The bad odor suction port 2 of the blower 1 is located near a bad odor generation source, such as a composting facility of a livestock farm, and can be used by appropriately connecting a suction duct.

The first tank 11 has a water tank 6 in which a sulfuric acid aqueous solution diluted to a predetermined concentration is stored, and a circulation pump for pumping the sulfuric acid aqueous solution in the water tank 6 to the water sprinkling pipe 15 via a water suction pipe 26. FIG. 4 that increases the contact between the pump 4 and the sparged sulfuric acid aqueous solution (liquid) and the malodorous gas (gas), that is, the gas-liquid contact
A gas-liquid contact promoting member 13 having a honeycomb structure as shown in
The aqueous sulfuric acid solution sprinkled from the water sprinkling pipe 15 neutralizes and absorbs the basic components in the offensive odor, returns to the water tank section 6, and is again pumped by the circulation pump 4, ie, the aqueous sulfuric acid solution is circulated. -It is being reused.

The gas-liquid contact promoting member 13 having a honeycomb structure includes:
Made of acid- and base-resistant plastic, width 50c
mx 100cm in depth x 50cm in height, cell size 13
mm and a surface area of 320 m 2 / m 3, and by filling the first tank in two stages, the sulfuric acid aqueous solution sprayed and sprayed from the water spray pipe 15 can be used for the honeycomb structure contact member 13.
As a result, the contact time and contact area between the sulfuric acid aqueous solution and the odorous gas are drastically increased, and the neutralization and absorption of the basic components in the odor are promoted.

The second tank 12 is provided with a water tank 7 for receiving a porous substance 30 containing calcium silicate as a main component and water, and pumps an aqueous solution in the water tank 7 to a water spray pipe 35 through a water pipe 27. It is composed of a circulation pump 5 and a gas-liquid contact promoting member 13 having a honeycomb structure for increasing the contact between the sprinkled aqueous solution (liquid) and the odorous gas (gas), that is, the gas-liquid contact. The used aqueous solution neutralizes and absorbs the acidic components in the offensive odor, returns to the water tank 7, and is again pumped by the circulation pump 5, that is, the aqueous solution is circulated and reused.

The gas-liquid contact promoting member 13 in the second tank is
The same material and the same size as the gas-liquid contact promoting member 13 in the first tank are filled in a two-tiered manner.

The porous substance 30 mainly composed of calcium silicate is mainly composed of siliceous raw materials such as silica stone, silica sand, cristobalite, amorphous silica, clay, and calcareous raw materials such as quicklime, slaked lime and cement. Manufactured as a building material manufactured by the after-form method, etc., in which a foaming agent (aluminum powder) that reacts with the alkali component of cement to generate hydrogen gas is added to concrete and uniformly mixed with the concrete, which has voids produced. Lightweight cellular concrete (AL
C) and the like, for example, tobermorite, zonotolite, CSH gel, fusoyagitite, gyrolite,
There are hill planidite and the like.

When the porous substance 30 containing calcium silicate as a main component is added to water, the pH of the porous substance 30 shifts to the alkali side to promote the neutralization and absorption of acidic components such as lower fatty acids. Since the pH value is lowered by neutralization with a fatty acid, it is desirable to use a porous substance material mainly composed of calcium silicate having a high pH buffering capacity and a large specific surface area for preventing the fluctuation of the pH value.

The porous substance 30 containing calcium silicate as a main component used in the present embodiment is described in JP-B-3-7815.
7. Tobermorite manufactured by the method described in No. 7 and having a donut shape (outer diameter 12 cm, inner diameter 8 cm, height 1)
5 cm).

In the deodorizing method of this embodiment, the malodorous gas is sucked by the blower 1 and
A treatment is performed to bring the first aqueous solution into contact with the aqueous sulfuric acid solution sprayed from the water spray pipe 15 of the first tank 11 by blowing air to the first tank 11.
The odor that has been subjected to the gas-liquid contact treatment in
And a process of bringing the solution into gas-liquid contact with the aqueous solution sprinkled from the sprinkling pipe 35 of the second tank 12 is performed.
The odor is removed and the gas is released into the atmosphere from the outlet.

Next, a test example of the deodorizing apparatus in this embodiment will be described.

Test Example 1 Ammonia gas as a representative of basic components of malodorous gas,
Normal butyric acid as a representative of the acidic component is mixed to remove both gases, and the p of aqueous solution in the first tank 11 and the second tank 12 is reduced.
The H value, electric conductivity, water temperature and ammonia nitrogen concentration were measured over time.

The operating conditions were as follows: 1 ton of a 5% by weight sulfuric acid aqueous solution, 1.5 m 3 in volume when donut type tobermorite was stacked, 1 m 3 of water in the second tank 12, a flow rate of the circulation pump 4 of 5.7 m 3 / h, circulation The flow rate of the pump 5 is 9.5m
3 / h, and the blowing rate of the blower 1 was 60 m3 / min.

The measurement was performed at point A near the vibration isolating duct 8 in FIG.
Performed at point B near the anti-vibration duct 9 and point C near the discharge port 3,
Point A was before processing, point B was an intermediate point, and point C was after processing.

The measurement of ammonia is carried out by inserting a gas detection tube for ammonia for a predetermined period of time into a measurement site by a gas detection tube method. For the measurement of normal butyric acid, an appropriate amount of gas is collected from each measurement site, concentrated and concentrated. Graphy (FI
D).

Ammonia was sucked into the blower 1 at a rate of 5 liters / min from a liquefied cylinder, and normal butyric acid was heated and vaporized by heating a pure product, and then sucked into the blower 1. Is 100 ppm,
The concentration of normal butyric acid is 480 ppb (0.480 pp
m).

According to the enforcement order of the Offensive Odor Control Law, the concentrations of ammonia and normal butyric acid which are perceived as offensive odor by human smell are greatly different. Since the reference concentration of butyric acid is also 0.001 ppm, the concentration setting in this test example was performed with reference to this.

The measurement results at this time are shown in Tables 1 and 2.

[0044]

[Table 1]

[0045]

[Table 2]

Also, the results of Tables 1 and 2 are graphed,
Changes in ammonia removal effect, normal butyric acid removal effect, ammonia removal rate and first tank pH value, normal butyric acid removal rate and second tank pH value, and changes in ammonia nitrogen concentration are shown in FIGS.

As can be seen from Tables 1 and 2, and FIGS. 5 to 9, ammonia shows a removal rate of 95% or more until 58 hours have passed, and normal butyric acid has an average of 95% until the end of the measurement (68 hours has passed). The above removal rates are shown.

Test Example 2 The spent sulfuric acid solution in Test Example 1 was drained from the drain port 23 of the water tank section 6, fresh 5 wt% sulfuric acid was adjusted and added to the water tank section 6, and tobermorite and water in the second tank 12 were added. Is Test Example 1
The test was carried out under the same conditions as in Test Example 1 except that the one used in Example 1 was used as it was.

At the point A, the concentration of ammonia was 100 ppm, and the concentration of normal butyric acid was 230 ppb.
(0.230 ppm) are shown in Tables 3 and 4 at this time.

[0050]

[Table 3]

[0051]

[Table 4]

Further, the results of Tables 3 and 4 are graphed,
Changes in ammonia removing effect, normal butyric acid removing effect, ammonia removing rate and first tank pH value, normal butyric acid removing rate and second tank pH value, and changes in ammonia nitrogen concentration are shown in FIGS.

As can be seen from Tables 3 and 4 and FIGS. 10 to 14, ammonia shows a removal rate of 95% or more up to 54 hours, and normal butyric acid ends the measurement (72 hours).
Up to 92%.

Test Example 3 The spent sulfuric acid solution in Test Example 2 was drained from the drain port 23 of the water tank section 6, and 1 ton of 10% by weight sulfuric acid was newly adjusted and added to the water tank section 6. Was replaced by draining, and tobermorite was used under the same conditions as in Test Example 1 except that the tobermorite used in Test Examples 1 and 2 was used as it was.

Tables 5 and 6 show the measurement results at this time.

[0056]

[Table 5]

[0057]

[Table 6]

Further, the results of Tables 5 and 6 are graphed,
FIGS. 15 to 19 show the ammonia removing effect, the normal butyric acid removing effect, the ammonia removing rate and the first tank pH value, the normal butyric acid removing rate and the second tank pH value, and the ammonia nitrogen concentration, respectively.

As can be seen from Tables 5 and 6, and FIGS. 15 to 19, ammonia shows a removal rate of 95% or more until 144 hours, and normal butyric acid shows 93% on average until the end of the measurement (152 hours). The above removal rates are shown.

The concentrations of ammonia and normal butyric acid before the treatment in Test Examples 1 to 3 were considerably higher than those in the composting facilities of ordinary livestock farmers. Although big,
Even with such a severe concentration of bad smell and high air flow, the deodorizing apparatus of the present embodiment provides excellent odor removal for 2.5 days or more in Test Example 1 or Test Example 2 and 6 days or more in Test Example 3. Rate (90% or more), and the amount of odor emitted from the outlet 3 per unit time is stably maintained at an extremely low level, and can contribute to the prevention of air pollution.

Therefore, it is clear that the concentration at the composting treatment facility of a normal livestock farmer shows an excellent odor removal rate over a longer period than in the test example, and the distance between the house and the livestock farm is clear. Even today, it is not uncommon for ordinary houses to surround livestock farms, so that odors are surely diluted to below a certain standard concentration at the borders of dwellings such as ordinary houses.

Further, the amount of smell of a worker such as a livestock farming farmer who has been exposed to a bad smell becomes extremely small, thereby preventing the health damage due to the bad smell and maintaining the work efficiency of the worker.

It is clear from the chart showing the transition of the ammonia nitrogen concentration that most of the ammonia is absorbed and removed in the first tank 11 by the neutralization reaction with sulfuric acid. It is also evident from the chart that the pH value of the water tank part 11 increases and the removal rate of ammonia drops sharply when the pH value exceeds 7.

Therefore, before the pH value rises to around 7, it is necessary to drain the used solution in the first tank 11 and fill it with a new sulfuric acid aqueous solution.
Ammonium sulfate aqueous solution, which has been conventionally used as nitrogen fertilizer as ammonium sulfate, so that livestock farmers can use this as fertilizer,
Since the used porous substance in the second tank 12 can also be used as a silicate calcareous fertilizer or a soil conditioner, resource saving can be doubled, and resources can be effectively used.

Normal butyric acid is also absorbed and removed in the first tank 11, but is mainly absorbed and removed in the second tank 12. In the second tank 12, the same results were obtained without replacing tobermorite in Test Examples 1 to 3. Despite the use, the removal rate of 90% or more was shown until the end of the measurement in Test Example 3 (292 hours or more, 12 days or more measured from Test Example 1),
The pH value in the second tank 12 is also maintained at about 7.5 to 8.5 by the pH buffering capacity of tobermorite.

The pH value of the second tank 12 exceeded 148 hours after Test Example 3 because the ammonia gas that could not be absorbed in the first tank 11 was changed to pH of tobermorite.
This is because it was absorbed in the second tank more than the buffer capacity.

Although the present invention has been described based on the embodiments, the present invention is not limited to these embodiments.

For example, the removal of offensive odor gas is carried out by a first treatment of bringing the sulfuric acid solution into gas-liquid contact, followed by a second treatment of bringing the porous material 30 mainly composed of calcium silicate into gas-liquid contact with the circulating liquid. Is preferably performed from the viewpoint of preventing leakage of harmful sulfuric acid gas from the discharge port, but the first process may be performed in the reverse order, that is, after the second process is performed.

The porous substance 30 containing calcium silicate as a main component is not limited to one kind. For example, tobermorite and zonotolite, CSH gel and fusoyagitite, tobermorite, zonotolite and CSH gel,
Multiple types can be used at the same time.

The gas-liquid contact promoting member 13 also does not need to have a honeycomb structure, and may be any member that promotes contact between the liquid and the gas.

Further, the application range of the deodorizing device is wide, and the deodorizing device can be used not only in a composting treatment facility in a livestock farm, but also in a place where a bad odor is generated.

[0072]

The deodorizing apparatus and the deodorizing method according to the present invention are configured as described above, and have the following effects.

(1) A cheap and easy-to-use material such as a porous substance containing dilute sulfuric acid and calcium silicate as a main component is used, and a basic component and an acidic component in a chemical odor are removed. Therefore, it is possible to achieve easy and highly efficient removal of odors, stable control of the amount of odors emitted from the outlet per unit time, and to reduce the distance between the house and the livestock farm, so that the general house surrounds the livestock farm. Even today, which is becoming increasingly rare and the speed of consolidation is increasing, there is an excellent effect that the offensive odor is surely diluted to a certain standard concentration or less at the boundary of a house such as a general private house.

(2) Since the odor is chemically and aggressively absorbed and removed, the amount of the odor released into the atmosphere is extremely small, and the odor of workers such as livestock farmers who have been exposed to the odor in the past is extremely low. The amount of smell is extremely small, which contributes to the prevention of air pollution and has the excellent effect of preventing health damage due to bad smell and maintaining the work efficiency of the worker.

(3) Since it is a chemical odor removal, the time required for the removal is very short, and a high level of specialized skill is not required for maintenance and management of the deodorizing device, and general odorless ones do not have specialized skills. It is very easy to handle for livestock farmers, requires a small installation area, and has an excellent effect of being highly versatile and economical.

(4) Ammonium sulfate and spent porous material generated after the malodor treatment can be used as nitrogen fertilizer, siliceous calcareous fertilizer, or soil conditioner, respectively, so that resource saving is doubled, and It has an excellent effect that saving and effective use are possible.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of a deodorizing apparatus according to the present invention.

FIG. 2 is a front view showing the same embodiment.

FIG. 3 is a top view showing the embodiment.

FIG. 4 is a perspective view showing a contact promoting member having a honeycomb structure used in the embodiment.

FIG. 5 is a graph showing the effect of removing ammonia in Test Example 1.

FIG. 6 is a graph showing the effect of removing normal butyric acid in the test example.

FIG. 7 shows the ammonia removal rate and the first tank p in the same test example.
The graph which shows H value.

FIG. 8 is a graph showing a normal butyric acid removal rate and a second tank pH value in the same test example.

FIG. 9 is a graph showing changes in the concentration of ammonia nitrogen in the test example.

FIG. 10 is a graph showing the effect of removing ammonia in Test Example 2.

FIG. 11 is a graph showing the effect of removing normal butyric acid in the test example.

FIG. 12 is a graph showing the ammonia removal rate and the first tank pH value in the same test example.

FIG. 13 is a graph showing the removal rate of normal butyric acid and the pH value of the second tank in the same test example.

FIG. 14 is a graph showing changes in the concentration of ammonia nitrogen in the test example.

FIG. 15 is a graph showing the effect of removing ammonia in Test Example 3.

FIG. 16 is a graph showing the effect of removing normal butyric acid in the test example.

FIG. 17 is a graph showing the ammonia removal rate and the first tank pH value in the same test example.

FIG. 18 is a graph showing a normal butyric acid removal rate and a second tank pH value in the same test example.

FIG. 19 is a graph showing changes in the concentration of ammonia nitrogen in the test example.

[Explanation of symbols]

 A Measurement point B Measurement point C Measurement point 1 Blower 2 Odor inlet 3 Outlet 4 Circulation pump 5 Circulation pump 6 Water tank unit 7 Water tank unit 8 Vibration-proof duct 9 Vibration-proof duct 10 Control panel 11 First tank 12 Second tank 13 Gas-liquid contact facilitating member 14 Demister 15 Sprinkler pipe 16 Inspection port 17 Inspection port 18 Inspection port 19 Inspection port 20 Inspection port 21 Inspection port 22 Overflow port 23 Drain port 24 Water supply port 25 Concrete base stand 26 Pumping pipe 27 Pumping pipe 30 Calcium silicate Porous substance mainly composed of 34 34 Demister 35 Watering pipe

Claims (5)

(57) [Claims] 1. A first tank configured to bring a malodorous gas into gas-liquid contact with a sulfuric acid solution, and a gas-liquid contact with a liquid circulating in contact with a porous material containing calcium silicate as a main component. A deodorizing device, characterized in that a malodor is removed by passing through the second tank configured. 2. The deodorizing apparatus according to claim 1, wherein the first tank is configured to circulate a sulfuric acid solution. 3. A gas-liquid contact promoting member is arranged in the first tank or the second tank.
The deodorizing device described. 4. The porous substance containing calcium silicate as a main component is one or more selected from the group consisting of tobermorite, zonotolite, CSH gel, fusiagitite, gyrolite, and hilleplandite. The deodorizing device according to claim 3. 5. A first treatment of bringing a malodorous gas into gas-liquid contact with a sulfuric acid solution, and a second treatment of making gas-liquid contact with a liquid circulating in contact with a porous substance containing calcium silicate as a main component. A deodorizing method characterized by removing a bad smell by carrying out.