JP4239720B2 - Odor gas treatment method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an odor gas processing method and apparatus.
[0002]
[Prior art and problems to be solved by the invention]
In general farms, the manure excreted by livestock is fermented by fermenting it. The odor gas generated in the fermentation process contains a maximum of several thousand ppm of ammonia and several ppm of methyl mercaptan, methyl sulfide, and methyl disulfide. When odorous gas containing such a component is released into the atmosphere, a bad odor is emitted to the neighborhood, causing troubles between residents and farmers living in the neighborhood.
Known methods for deodorizing odorous gases include water (or chemical) cleaning methods, sawdust adsorption methods, and microbial decomposition methods. However, the above-mentioned deodorizing treatment method involves water (chemical solution) treatment and requires a relatively large site area, so that it is difficult for general farmers to use. In recent years, a combustion deodorization method in which odor gas is burned in a furnace (deodorization furnace) to thermally decompose odor components of the odor gas at a high temperature has been studied. However, in this combustion deodorization method, a large amount of solid foreign matter is carried along the flow of odor gas. For this reason, it has been studied to filter the odor gas with an air filter before the combustion, but there is a concern that the air filter may be clogged quickly due to the large amount of solid foreign matter.
[0003]
[Non-Patent Document 1]
Yasumitsu Takahara, “Deodorization of Vertical Sealed Fermenter Odor by Direct Combustion Combustion Deodorizer”, Livestock Consultant, March 2001, p.58-63
[0004]
The present invention has been made in view of the above-described problems, and an object of the present invention is to more reliably treat odor gas by eliminating problems caused by solid foreign substances carried on the flow of odor gas. Is.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the odor gas treatment method according to the present invention is a method for deodorizing the odor gas by burning it with fuel using the odor gas generated when fermenting livestock feces as an air source. The combustible foreign matter having a size that does not reduce the desired deodorizing ability of the odor gas among the solid foreign matters carried on the odor gas flow is burned simultaneously with the odor gas. To do.
[0006]
Further, the odor gas treatment device according to the present invention is a device for deodorizing the odor gas by burning the odor gas generated when fermenting the animal feces together with fuel as an air source, and fermenting the animal feces. A livestock excrement fermenter, and the desired combustion capacity of the combustion engine among solid foreign matters that are burned together with fuel using the odor gas generated in the livestock fecal fermenter as an air source and carried on the flow of the odor gas And a combustion engine that combusts combustible foreign matter having a size that does not reduce the odor gas simultaneously with the odor gas.
[0007]
By adopting such a configuration, combustible foreign matter is combusted, and therefore, odor gas can be deodorized without considering removing the combustible foreign matter before combustion.
[0008]
Moreover, it is preferable to remove the solid foreign matter having a size larger than the combustible foreign matter by filtering the odor gas before the combustion.
As a result, solid foreign matters more than combustible foreign matters are removed, so that solid foreign matters that reduce the deodorizing ability of odorous gas before combustion are removed.
In addition, when filtering odor gas, it is preferable to use an air filter with a resistance of 70 to 100 mmAq.
[0009]
The odor gas contains 8 to 13% of moisture. For this reason, moisture will condense with solid foreign matter, and it will be in the state where it will be easy to adhere to the above-mentioned air filter etc., and it will be in the state where solid foreign matter tends to adhere to an air filter by moisture condensing to an air filter etc. Therefore, there is a concern that the air filter is clogged immediately.
Therefore, it is preferable to warm the odor gas before filtering the odor gas. As a result, it is possible to prevent moisture from condensing with the solid foreign matter, thereby preventing the air filter from being clogged.
Moreover, when heating odor gas, it is preferable to heat odor gas using the exhaust gas produced | generated by the above-mentioned combustion.
As a result, it is not necessary to separately install a heater or the like for heating the odor gas, so that the air filter is prevented from being clogged at a low cost.
In addition, when heating odor gas, it is preferable to heat-exchange the exhaust gas and odor gas of a combustion engine with a heat exchanger.
[0010]
Further, before the combustion, it is preferable to remove the solid foreign matter having a size larger than the combustible foreign matter by rotating the odor gas using a cyclone and utilizing the centrifugal force. This further removes solids larger than combustible foreign matter.
The cyclone is more preferably provided before the above-described air filter. As a result, solid foreign matters having a size larger than combustible foreign matters can be removed to some extent before the air filter, thereby further preventing the air filter from being clogged.
[0011]
Moreover, it is preferable to remove the solid foreign substances larger than the combustible material by flowing the odor gas into the heated water using a water tank before the combustion. This further removes solids larger than combustible foreign matter.
In addition, it is more preferable that the water tank is provided before the above-described air filter. Accordingly, solid foreign matters larger than combustible foreign matters can be removed to some extent before the air filter, and moisture contained in the odor gas can be removed to some extent, so that the air filter is further prevented from being clogged.
Moreover, it is preferable to heat the water stored in the water tank with the exhaust gas. Accordingly, there is no need to provide a heating means for separately heating the water stored in the water tank, so that solid foreign matters having a size larger than the combustible foreign matter can be removed at low cost.
[0012]
Moreover, it is preferable to generate electric power using energy obtained by the above-described combustion. As a result, the electric power required in the present odor gas processing method and apparatus can be obtained, so that the odor gas can be processed at a lower cost.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of an odor gas processing method and apparatus according to the present invention will be described with reference to the drawings. In addition, this embodiment demonstrates the case where the odor gas emitted from chicken droppings (livestock droppings) is processed.
[0014]
FIG. 1 is a block diagram of the odor gas processing apparatus for processing odor gas using the odor gas processing method. In this figure, reference numeral 1 is a chicken manure place (livestock manure place), 2 is a chicken manure fermenter (livestock manure fermenter), 3 is a first blower, 4 is a cyclone, 5 is a water tank, 6 (6a, 6b) is an air filter, 7 Is a combustion engine, 8 is a generator, 9 (9a, 9b) is a catalyst, 10 is a first heat exchanger, 11 is a second blower, 12a to 12d are three-way valves, and 13 is a second heat exchanger (heat exchanger). ), W is fuel, X is chicken manure (livestock manure), Y is odor gas, and Z is exhaust gas.
[0015]
The chicken manure yard 1 is a place for temporarily storing the chicken manure X excreted by chickens kept as livestock, and the odor gas Ya generated from the chicken manure X stored in the chicken manure depot 1 is not leaked to the outside. It has a structure. The chicken manure storage place 1 is preferably installed in the vicinity of the chicken manure fermenter 2 in consideration of the ease of transporting the chicken manure X.
[0016]
The chicken manure fermenter 2 ferments the chicken manure X into fertilizer, and for example, a continuous fermenter that continuously aerobically ferments the chicken manure X can be used.
The first blower 3 blows the odor gas Y generated in the chicken manure fermenter 2 to the subsequent cyclone 4.
[0017]
The cyclone 4 removes relatively large chicken dung dust from chicken dung dust (solid foreign matter) carried on the flow of the odor gas Y.
A cyclone is a dust collector that increases the sedimentation speed of particles using centrifugal force, and is a device that separates using centrifugal force of dust-containing particles that give rotational motion to the gas and rotate with it. is there. Compared with gravity sedimentation, centrifugal force that is several hundred times the gravity acts to separate, so high performance can be obtained with small equipment. The dust-containing gas entering the tangential direction from the upper part of the cylinder descends while turning along the inner wall of the cylinder, enters the conical part of the lower part, rises while turning, and is discharged from the inner cylinder. While the air current swirls and descends along the cylinder and the inner wall of the cone, particles in the air current move toward the wall by centrifugal force, and particles that have reached the wall surface slide down along the wall surface due to gravity and fall into the cone part. Accumulate in the connected dust bin.
Moreover, chicken manure dust is a foreign material carried on the flow of the odor gas Y, and examples thereof include chicken wings. This chicken manure dust is contained in the odor gas Y discharged from the chicken manure fermenter 2 in an amount of 0.05 to 0.45 g / Nm ³ .
[0018]
The water tank 5 is provided after the cyclone 4 to remove relatively small chicken manure dust that could not be removed by the cyclone 4 and to remove moisture contained in the odor gas Y.
Specifically, the odor gas Y is put into the water stored in the water tank 5, and the ammonia dissolved in the water is vaporized and discharged by heating the water.
[0019]
The 2nd heat exchanger 13 is provided in the back | latter stage of the water tank 5, and heats the odor gas Y by heat-exchanging the exhaust gas Z and the odor gas Y of the combustion engine 7 mentioned later.
[0020]
The air filter 6 removes chicken manure dust that has not been removed in the cyclone 4 and the water tank 5, and two air filters 6a and 6b are provided. The resistance of the air filter 6 is 70 to 100 mmAq. A three-way valve 12 a is provided at the front stage of the air filter 6, and a three-way valve 12 b is provided at the rear stage of the air filter 6.
By this three-way valve 12a, the odor gas Y discharged from the second heat exchanger 13 is selectively introduced into the air filter 6a or the air filter 6b.
The three-way valve 12b is adjusted corresponding to the three-way valve 12a.
As described above, since the three-way valves 12a and 12b are provided, even when one of the air filters 6a and 6b is cleaned, the operation of the odor gas processing apparatus can be performed without stopping. Become.
[0021]
The combustion engine 7 is a small diesel engine that is provided downstream of the three-way valve 12b and uses kerosene W as fuel and odor gas Y as an air source. The combustion engine 7 performs a deodorizing process by burning the odor gas Y together with the kerosene W. As a small diesel engine using such kerosene as fuel, N88L manufactured by Ishikawajima Shibaura Machinery Co., Ltd. can be mentioned.
[0022]
The generator 8 generates power using the combustion engine 7 as a drive source, and is installed in contact with the combustion engine 7.
The electric power generated by the generator 8 is supplied to the first blower 3 and the second blower 11.
[0023]
The catalyst 9 removes the ammonia remaining in the exhaust gas Z by denitrating the exhaust gas Z exhausted from the combustion engine 7, and two catalysts 9a and 9b are provided.
A three-way valve 12 c is provided in the front stage of the catalyst 9, and a three-way valve 12 d is provided in the rear stage of the catalyst 9.
By this three-way valve 12c, the exhaust gas Z selectively flows into the catalyst 9a or the catalyst 9b.
The three-way valve 12d is adjusted corresponding to the three-way valve 12c.
As described above, since the three-way valves 12c and 12d are provided, even when one of the catalysts 9a and 9b is replaced, the operation of the odor gas processing apparatus can be performed without stopping.
[0024]
As shown in the figure, the first heat exchanger 10 is provided at the rear stage of the catalyst 9 and exchanges heat between the exhaust gas Z and the odor gas Ya generated in the chicken manure storage 1 to thereby provide the odor gas Ya. Is for heating.
The second blower allows the odor gas Ya to flow into the chicken manure fermenter 2 described above.
As shown in the figure, the passage path of the exhaust gas Z passes through the water tank 5, and the water stored in the water tank 5 is heated by the exhaust gas Z.
Therefore, since it is not necessary to provide a heating means for heating the water stored in the chicken manure fermenter 2 and the water tank 4, the manufacturing cost and the operating cost are reduced.
[0025]
Next, the present odor gas processing method by the present odor gas processing apparatus configured as described above will be described.
[0026]
The chicken manure X excreted from the chicken is temporarily stored in the chicken manure storage 1 and then transported to the chicken manure fermenter 2. Further, the odor gas Ya generated in the chicken manure storage place 1 is blown to the first heat exchanger 10 by the second blower 11 and is heated by heat exchange with the exhaust gas Z described above in the first heat exchanger 10. After that, it flows into the chicken manure fermenter 2.
[0027]
The chicken manure X is subjected to aerobic fermentation in the chicken manure fermenter 2 that is suitably heated (for example, 70 ° C.) by the odor gas Ya, and as a result, fertilizer and odor gas Y are generated. The odor gas Y generated in the chicken manure fermenter 2 is blown to the cyclone 4 by the first blower 3. The odor gas Y has an ammonia concentration of 300 to 3000 ppm, an oxygen concentration of 18 to 21%, and a moisture content of 5 to 15%. In addition, the odor gas Y contains 0.05 to 0.45 g / Nm ³ of chicken manure dust. Moreover, the temperature of the odor gas Y discharged | emitted from the chicken manure fermenter 2 is 35-60 degreeC. The fertilizer is carried out of the chicken manure fermenter 2 and reused in a field or the like.
[0028]
The odor gas Y flows into the water stored in the water tank 5 after the relatively large chicken dung dust is removed by the cyclone 4. The odor gas Y flows toward the second heat exchanger 13 after removing relatively small chicken manure dust by flowing into the water stored in the water tank 5.
Note that when the odor gas Y flows into the water stored in the water tank 5, the ammonia contained in the odor gas Y is temporarily dissolved in the water, but the water is heated by the exhaust gas Z. Ammonia dissolved in water is vaporized.
In addition, the water stored in the water tank 5 is drained outside after use.
[0029]
Subsequently, the odor gas Y is heated by the second heat exchanger 13 until it reaches about 70 ° C. or higher. Since the chicken manure fermenter 2 is heated to about 70 ° C. as described above, if the odor gas Y is heated to 70 ° C. or more by the second heat exchanger 13, it is included in the odor gas Y. The dissolved water is dissolved in the odor gas Y. For this reason, it is possible to prevent moisture contained in the odor gas Y from condensing when the odor gas Y passes through the subsequent air filter 6, and as a result, clogging of the air filter 6 can be prevented. .
[0030]
Thereafter, the odor gas Y is selectively passed through the air filter 6a or the air filter 6b by the three-way valve 12a, thereby removing the chicken manure dust that has not been removed by the cyclone 4 and the water tank 5 and then the combustion engine. 7 flows as an air source.
As described above, since the resistance of the air filter 6 is 70 to 100 mmAq, only a part of the chicken manure dust (combustible foreign matter) passes through the air filter 6 and flows into the combustion engine 7 together with the odor gas Y. To do. The chicken manure dust that has passed through the air filter 6 is only of a size that does not reduce the combustion capacity of the combustion engine 7, and is burned together with the odor gas Y by the combustion engine 7.
Therefore, it is possible to prevent the air filter 6 from being clogged by causing the combustion engine 7 to burn chicken dung dust having a size that does not actively reduce the combustion capacity.
[0031]
The odor gas Y is discharged as exhaust gas Z after being deodorized by being burned by the combustion engine 7 together with kerosene W. In addition, the temperature of this exhaust gas Z is about 250-350 degreeC.
In addition, as shown in the following formula (1), in the combustion engine 7, nitrogen oxides are generated by the oxidation of ammonia contained in the odor gas Y. However, since this nitrogen oxide undergoes a reduction reaction with ammonia contained in the odor gas Y newly supplied into the combustion engine 7 as shown in the following formula (2), the nitrogen oxide of the exhaust gas Z The concentration drops to a level that is possible even when released into the atmosphere.
NH ₃ + O ₂ = NOx + (1)
NOx + NH ₃ = N ₂ + (2)
[0032]
The exhaust gas Z discharged from the combustion engine 7 is selectively blown to the catalyst 9a or the catalyst 9b by the three-way valve 12c, whereby ammonia, nitrogen oxides, etc. remaining in the exhaust gas Z are further removed. .
[0033]
Thereafter, the exhaust gas Z warms water in the water tank 5, warms the odor gas Ya in the first heat exchanger 10, and warms the odor gas Y in the second heat exchanger, and is then discharged to the outside. The The electric power generated by the generator 8 using the combustion engine 7 as a drive source is transmitted to the first blower 3 and the second blower 11, thereby driving the first blower 3 and the second blower 11.
[0034]
As described above, according to the present odor gas processing method and apparatus, the air filter 6 is not clogged with the chicken manure dust. Therefore, the problem caused by the chicken manure dust carried on the flow of the odor gas Y can be solved more reliably. It is possible to treat odor gas.
Further, the water, the odor gas Ya, and the odor gas Y in the water tank 5 are heated by the exhaust gas Z, and further, the first blower 3 and the second blower are generated by the electric power generated by the generator 7 using the combustion engine 7 as a drive source. 11 is driven, the odor gas Y can be processed at low cost.
In addition, since kerosene W is used as the fuel for the combustion engine 7, it is possible to suppress the generation of flue gas particulates and improve fuel efficiency compared to the case where light oil is used as the fuel.
[0035]
(Example)
In the odor gas processing apparatus having the same configuration as in the above embodiment, when the air filter 6 having a resistance of 70 to 100 mmAq is used, the air filter 6 may not be clogged during at least one batch operation period (3 to 4 days). confirmed. When an air filter having a resistance of 200 mmAq was used, it was confirmed that the differential pressure before and after the air filter increased to 700 mmAq in about 1 hour, and the air filter was clogged.
[0036]
Further, when the measurement was performed by operating the combustion engine 7 at 8.6 kW, the odor gas Y before flowing into the combustion engine 7 had an ammonia concentration of 2700 ppm, an oxygen concentration of 18.8%, and an odor concentration of 550,000. In contrast, the exhaust gas Z exhausted from the combustion engine 7 had an ammonia concentration of 170 ppm, an oxygen concentration of 9.8%, an odor concentration of 41000, and an NOx concentration of 392 ppm. From this result, it was confirmed that the odor gas Y can be deodorized more reliably.
[0037]
Further, the odor gas Y discharged from the chicken manure fermenter 2 contained 0.05 to 0.45 g / Nm ^{3 of} chicken manure dust. However, by using kerosene W as the fuel, it was discharged from the combustion engine 7. The exhaust gas Z concentration of the exhaust gas Z was suppressed to 0.0018 to 0.0033 g / Nm ³ .
[0038]
As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the above-described embodiments. Various shapes and combinations of the constituent members shown in the above-described embodiments are merely examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.
[0039]
For example, the present invention is not limited to poultry manure as animal manure, but can also be applied to the treatment of odor gas generated when the animal manure of other animals is fermented.
Further, a differential pressure sensor may be installed before and after the air filter 6 so that the degree of clogging of the air filter 6 can be detected.
[0040]
【The invention's effect】
As described above, according to the present invention, a method of deodorizing the odor gas by burning the odor gas generated when fermenting livestock feces with the fuel as an air source, By burning the combustible foreign matter that is of a size that does not reduce the desired deodorizing ability of the odor gas among solid foreign matters carried on the flow, it can ride on the flow of odor gas by burning it simultaneously with the odor gas. By eliminating the problems caused by the solid foreign substances that are carried, the odor gas can be treated more reliably.
[Brief description of the drawings]
FIG. 1 is a block diagram of an odor gas processing apparatus that processes odor gas using an odor gas processing method according to an embodiment of the present invention.
[Explanation of symbols]
1 ... Chicken manure (livestock manure)
2 ... Chicken manure fermenter (livestock manure fermenter)
3 ... 1st blower 4 ... Cyclone 5 ... Water tank 6 (6a, 6b) ... Air filter 7 ... Combustion engine 8 ... Generator 9 (9a, 9b) ... Catalyst 10 ... First heat exchange Unit 11 …… Second blowers 12a to 12d …… Three-way valve 13 …… Second heat exchanger (heat exchanger)
W ... Fuel X ... Chicken dung (livestock dung)
Y, Ya …… Odor gas Z …… Exhaust gas

Claims (12)

A method of deodorizing the odor gas by burning the odor gas generated when fermenting livestock feces with fuel as an air source,
Of the solid foreign substances carried on the flow of the odor gas, the solid foreign substances having a size not smaller than the combustible foreign substance that does not reduce the desired deodorizing ability of the odor gas, and the odor gas. At least one of a step of turning and removing the centrifugal foreign matter by utilizing the centrifugal force and a step of removing the solid foreign matter larger than the combustible substance by flowing the odorous gas into the heated water And
After the step, the odor gas is heated, and the heated odor gas is filtered to further remove the solid foreign matters larger than the combustible foreign matter,
An odor gas treatment method comprising burning the combustible foreign matter simultaneously with the odor gas by burning the filtered odor gas.     The odor gas treatment method according to claim 1, wherein the odor gas is heated to a temperature higher than or equal to a temperature in an animal manure fermenter in which the animal manure is fermented before the odor gas is filtered.     3. The odor gas processing method according to claim 1, wherein two air filters for filtering the odor gas are provided, and the odor gas selectively flows into one of the air filters. 4.     The odor gas processing method according to claim 1, wherein the odor gas is heated by exhaust gas generated in the combustion. The odor gas treatment method according to any one of claims 1 to 4, wherein the water is heated by the exhaust gas generated in the combustion . The odor gas processing method according to claim 1, wherein power is generated by energy obtained by the combustion . An apparatus for deodorizing the odor gas by burning the odor gas generated when fermenting livestock feces together with fuel as an air source,
An animal manure fermenter for fermenting the animal manure;
Of the solid foreign substances carried along the flow of the odor gas, the solid alien substance having a size larger than the combustible foreign substance having a size that does not reduce the desired combustion capacity of the combustion engine is swirled with the odor gas. At least one of a cyclone to be removed by utilizing the centrifugal force and a water tank to be removed by allowing the odorous gas to flow into water in which the solid foreign matter having a size larger than the combustible foreign matter is heated.
A heat exchanger that heats the odor gas from which the solid foreign matter having a size larger than the combustible foreign matter is removed in at least one of the cyclone and the water tank by the exhaust gas of the combustion engine;
An air filter for further removing the solid foreign matter having a size larger than the combustible foreign matter from the odor gas heated in the heat exchanger;
Combusting with the odor gas from which the solid foreign matters larger than the combustible foreign matters in the air filter are further removed as an air source and burning together with the fuel, and burning the combustible foreign matters simultaneously with the odor gas With the institution
An odor gas treatment apparatus comprising: The odor gas processing apparatus according to claim 7, wherein the heat exchanger warms the odor gas to a temperature equal to or higher than the temperature in the animal manure fermenter. The odor gas processing apparatus according to claim 7 or 8, further comprising a three-way valve that has two air filters and selectively allows the odor gas to flow into any one of the air filters . 10. The odor gas treatment apparatus according to claim 7, wherein the resistance of the air filter is 70 to 100 mmAq . Odorous gas processing device according to claim 7 to 10 either you wherein warming the water by the exhaust gas of the combustion engine. The odor gas processing apparatus according to any one of claims 7 to 11, further comprising a generator that generates electric power using the combustion engine as a drive source .

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