JP6935900B2 - Deodorization and nitrogen removal method - Google Patents

Description

The present invention relates to, for example, a method for removing an odor mainly composed of ammonia generated from a process of treating livestock excrement and removing nitrogen, and a deodorizing and nitrogen removing device used in the method.

Conventionally, in the composting treatment of livestock manure, an odor mainly composed of ammonia is generated, so that a biological deodorizing method in which biological treatment is performed using microorganisms is often used. In a biological deodorization system, ammonia gas is removed from the gas phase by dissolution in water and then converted to nitrite or nitric acid by a nitrification reaction by microorganisms. In addition, water is generally sprinkled in order to maintain the activity of deodorizing microorganisms, and deodorized wastewater containing ammonia, nitric acid, and nitrite is generated. When water is recycled (circular watering method), nitrogen accumulates, resulting in a decrease in microbial activity in the long term.
Therefore, there is a demand for a technique for efficiently removing nitrogen from biological deodorized wastewater.

As a method of suppressing a decrease in microbial activity of a circulating watering type biological deodorizing device, a method of reducing the ion concentration of watering water to an appropriate concentration by dilution (Patent Document 1) is known. In this method, the upper limit of the ion concentration is set to 10,000 ppm or less for nitrite and nitrate ion concentration, 5,000 ppm or less for sulfate ion concentration, and 100 mS / m or less for electrical conductivity.

On the other hand, a biological deodorizing method using denitrification has also been developed (Patent Documents 2 to 6 and Non-Patent Document 1 and the like). Patent Document 2 discloses a system in which nitrifying bacteria and denitrifying bacteria are allowed to inhabit a porous wood-based filter medium, and water that has absorbed odor is sprinkled on the upper surface of the filter medium. Patent Document 3 discloses a system in which waste cast sand is used as a deodorizing material and composted dew condensation water and deodorized waste water are treated in a deodorizing tank. Organic matter derived from organic waste, which is a source of odor, is used for denitrification. Patent Document 4 and the like propose a system separately provided with a device for supplying an organic substance as a nutrient for microorganisms having a denitrifying action. Further, Patent Documents 5 and 6 disclose a system in which nitrification is suppressed, a nitrite solution is obtained, and denitrification is performed by anammox bacteria in the nitrification reaction after removal by absorption of ammonia. As these nitrite formation methods, an ammonium ion concentration, a nitrite concentration, a pH control range, and the like are shown. In addition, Non-Patent Document 1 reports that granules composed of ammonia-oxidizing bacteria and anammox bacteria can be added to a biological deodorizing tank, and nitrite and denitrification can be simultaneously performed in the deodorizing tank. Nitrite formation is mainly controlled by the ion concentration. That is, the methods for controlling nitrite in Patent Documents 5 and 6 and Non-Patent Document 1 utilize the difference in resistance to free ammonia or free nitrite concentration of the nitrite-nitrating bacteria. Conceivable.

However, as described above, in the method of simply lowering the ion concentration by dilution, it is necessary to replenish a large amount of water and the amount of deodorized wastewater also increases, so that the running cost increases due to the wastewater treatment cost and the water cost. If a denitrifying device is provided separately from the biological deodorizing device, the equipment cost will be high. In a system that uses a porous organic filter medium as an electron donor for denitrification or supplies organic matter derived from organic waste that is a source of odor, the mass balance is unclear and the inflow load fluctuates. It is difficult to control the denitrification reaction.

Further, in a system in which an organic substance is added or used as an electron donor, it may be necessary to treat the residual organic substance, which further complicates the system.

With the method using anammox bacteria, the growth rate of anammox bacteria is slow, and it is currently difficult to obtain anammox sludge or granules composed of ammonia-oxidizing bacteria and anammox bacteria. In addition, nitrate formation is relatively easy to proceed in the biological deodorization tank, and it is difficult to stably maintain nitrite formation. In the anammox reaction, some nitric acid is generated, and a denitrification step of nitric acid may be required in the subsequent stage.

As described above, there is still a demand for a technique for removing an odor mainly composed of ammonia generated from a process of treating livestock excrement and at the same time removing nitrogen.

By the way, Patent Document 7 discloses that Oya stone is used for adsorbing an odor in a deodorizing method.

Further, Patent Document 8 discloses that nitrifying bacteria and zeolite are supported on a carrier in a method for purifying polluted water.

Further, Patent Document 9 states that sodium thiosulfate is used as an electron donor when a denitrifying bacterium denitrifies nitrate ions and nitrite ions under anaerobic conditions in a method for removing nitrogen oxides in the atmosphere. Disclose.

Japanese Unexamined Patent Publication No. 2000-42353 JP-A-2002-273154 Japanese Patent No. 3638010 Japanese Unexamined Patent Publication No. 2006-35028 Japanese Patent No. 5008249 Japanese Unexamined Patent Publication No. 2010-274160 Japanese Unexamined Patent Publication No. 2004-236865 Japanese Unexamined Patent Publication No. 11-262790 Japanese Unexamined Patent Publication No. 7-256055

De Clippeleir et al. 2012. Environmental Science and Technology. 46: 8826-8833

Therefore, in view of the above-mentioned circumstances, it is an object of the present invention to provide a method for removing an odor mainly composed of ammonia generated from a process of treating livestock excrement and the like, and at the same time removing nitrogen.

As a result of diligent research to solve the above problems, in a circulating watering type biological deodorizer (reactor), denitrification using thiosulfuric acid as an electron donor is performed at the same time in a deodorizing tank that performs a nitrification reaction. It has been found that the odor mainly composed of ammonia can be efficiently removed and nitrogen can be removed at the same time, and the present invention has been completed.

The present invention includes the following.
(1) A deodorizing tank filled with a deodorizing material inoculated with activated sludge for subjecting ammonia gas to a nitrification reaction and a sulfur denitrification reaction, and a water supply tank for supplying water containing sodium thiosulfate to the deodorizing tank. Deodorizing and denitrifying treatment equipment.
(2) The apparatus according to (1), wherein ammonia gas is generated from the process of treating livestock excrement.
(3) The device according to (1) or (2), wherein the deodorizing material is Oya stone or rock wool.
(4) The apparatus according to any one of (1) to (3), wherein the water further contains sulfur denitrifying sludge.
(5) The device according to any one of (1) to (4), wherein the pH of water is 7.0 to 8.8.
(6) A deodorizing and denitrifying treatment method comprising a step of subjecting ammonia gas to a nitrification reaction and a sulfur denitrification reaction in the presence of a deodorizing material inoculated with activated sludge and sodium thiosulfate.
(7) The method according to (6), wherein the ammonia gas is generated from the process of treating livestock excrement.
(8) The method according to (6) or (7), wherein the deodorizing material is Oya stone or rock wool.
(9) The method according to any one of (6) to (8), wherein the reaction is further carried out in the presence of sulfur denitrifying sludge.
(10) The method according to any one of (6) to (9), wherein the reaction is carried out at pH 7.0 to 8.8.

According to the present invention, it is possible to remove an odor mainly composed of ammonia generated from a process of treating livestock excrement and the like, and at the same time remove nitrogen.

It is a schematic diagram which shows the deodorizing and denitrifying treatment apparatus which concerns on this invention. It is a figure which shows the outline of the reactor used in an Example. It is a graph which shows the transition of ammonia nitrogen trapped with sulfuric acid. It is a graph which shows the time-dependent change of the ion concentration and pH in circulating water.

The deodorizing and denitrifying treatment apparatus according to the present invention (hereinafter referred to as “the apparatus”) is a deodorizing tank filled with a deodorizing material inoculated with activated sludge, which subject ammonia gas, which is an odor, to a nitrification reaction and a sulfur denitrification reaction. And a water supply tank for supplying water containing sodium thiosulfate to the deodorizing tank. Further, the deodorizing and denitrifying treatment method according to the present invention is a step of subjecting ammonia gas to a nitrification reaction and a sulfur denitrification reaction in the presence of a deodorizing material inoculated with activated sludge and sodium thiosulfate using this apparatus. It includes.

In the present invention, in a circulating watering type biological deodorizing device (this device), denitrification using thiosulfuric acid as an electron donor is simultaneously performed in a deodorizing tank that performs a nitrification reaction. As a means for that purpose, sodium thiosulfate is appropriately added to the existing circulating water tank (water supply tank), and if necessary, sulfur denitrified sludge accumulated with sodium thiosulfate and nitric acid is appropriately added to the deodorizing tank.

Specifically, in the reactor (this device), the deodorizing tank is filled with a deodorizing material inoculated with activated sludge, and ammonia gas, which is a malodorous component, is passed through, while sodium thiosulfate is added to the circulating water in the water supply tank. As a reaction, ammonia is nitrified by microorganisms (nitrifying bacteria) in the active sludge that has grown on the surface of the deodorizing material while being adsorbed on the deodorizing material, and converted to nitrite and nitric acid, while thio as a sulfur source. By adding sodium sulfate, sulfur denitrification reaction occurs due to sulfur-oxidizing bacteria in active sludge, thiosulfate reacts with nitrite and nitric acid, and sulfuric acid is generated by oxidation of thiosulfate, and nitrogen is used as nitrogen gas. Remove. In this way, ammonia is removed in the reactor and nitric acid in the circulating water is reduced.

Here, examples of the ammonia gas include those generated from a livestock excrement treatment process such as a composting process of livestock manure. Further, the present invention can treat ammonia gas not only in livestock farming but also in fertilizer manufacturing factories, waste treatment plants, sewage treatment plants, food processing plants and other workplaces that generate malodor mainly containing ammonia.

Examples of the deodorizing material include Oya stone, rock wool, pumice stone and the like, and Oya stone or rock wool is preferable. Examples of the Oya stone used in the present invention include commercially available Oya stone powder (2 to about 10 mm diameter) such as Oya stone grains produced in Tochigi Prefecture. Further, the rock wool used in the present invention is an artificial mineral fiber produced by melting natural rock such as basalt or blast furnace slag at a high temperature and fiberizing it, for example, a commercially available rock wool deodorant or the like. You can use things.

In addition, examples of the activated sludge to be inoculated into the deodorizing material filled in the deodorizing tank of this apparatus include activated sludge derived from pig farming wastewater treated by the activated sludge method in a pig farming wastewater treatment facility. For example, activated sludge from a pig farm wastewater treatment facility is filtered with nitrifying bacteria medium (Juhler S., Revsbech NP, Schramm A., Herrmann M., Ottosen LDM and Nielsen LP (2009) Distribution and rate of microbial processes in an ammonia-loaded air filter. biofilm. Appl. Environ. Microbiol. 75: 3705-3713. Or in Kruemmel and Heinz (1982) Effect of organic matter on growth and cell yield of ammonia-oxidizing bacteria. Arch. Microbiol. 133: 50-54, etc.) 15 ~ It can be aerobically cultivated at 30 ° C. (preferably 28 ° C.) for several weeks, and the obtained culture can be used as activated sludge. Further, before the operation of the apparatus, the culture can be carried out in the deodorizing tank of the apparatus in the presence of a deodorizing material.

Activated sludge is washed with nitrifying bacteria medium or distilled water by centrifugation, and then inoculated at a ratio of, for example, 10 to 30% (v / v) to the deodorizing material.

Further, sulfur denitrifying sludge containing mainly sulfur-oxidizing bacteria that undergoes a sulfur denitrification reaction may be added to water containing sodium thiosulfate (circulating water) supplied from the water tank. Sulfur denitrification medium (Sho Hashimoto, Kenji Furukawa, Masahiko Shioyama (1989) Accumulation of sulfur denitrifying bacteria and adaptation to elemental sulfur. Water pollution research, 12, 431-440) and activated sludge are, for example, 9: 1 (vol). Mix to a ratio of / vol) and anaerobically cultivate at 20-35 ° C for about a week. After culturing, the culture (activated sludge) recovered by centrifugation or the like can be used as the sulfur denitrifying sludge in the present invention. Sulfur denitrification sludge is added, for example, 2 to 3 g (wet weight) per 1 L of water tank. Activated sludge and sulfur denitrifying sludge to be inoculated into deodorant materials belong to nitrifying bacteria (for example, Nitrosomonadaceae, which is an ammonia-oxidizing bacterium, and Nitrospira, which is a nitrite-oxidizing bacterium). It contains (belonging to microorganisms) and sulfur denitrifying bacteria (for example, microorganisms belonging to the genus Thiobacillus such as T. thiophilus and T. thioparus) that perform a sulfur denitrification reaction.

The sodium thiosulfate content in the circulating water supplied from the water supply tank is, for example, 200 to 6,000 mg / L (preferably 500 to 3,000 mg / L).

In addition, lower pH is thought to inhibit ammonia oxidation because it causes a lower concentration of non-ionic ammonia, a form available to ammonia-oxidizing bacteria (Suzuki I., Dular U. and Kwok SC). (1974) Ammonia or ammonia as substrate for oxidation by Nitrosomonas europaea cells and extracts. J. Bacteriol. 120: 556-558). Therefore, the pH of the water containing sodium thiosulfate (circulating water) supplied from the water supply tank is preferably controlled to the weak alkaline side (for example, pH 7.0 to 8.8, preferably around pH 7.5).

FIG. 1 is a schematic view showing an example of this device. As shown in FIG. 1, the apparatus 1 includes a deodorizing tank 2 and a water supply tank 3 for supplying water containing sodium thiosulfate to the deodorizing tank. Further, in the present device 1, a storage tank 4 may be provided between the deodorizing tank and the water supply tank.

The deodorizing tank 2 is filled with a deodorizing material inoculated with activated sludge. The deodorizing material inoculated with activated sludge is filled in the deodorizing tank 2 at, for example, about 0.4 kg / L for rock wool deodorizing material before water addition and about 0.9 kg / L for Oya stone grains.

Ammonia gas 5 is ventilated from the lower part of the deodorizing tank 2 at, for example, an ammonia volume load: 35 to 65 NH ₃ / m ³ / day. The apparatus 1 may include means for controlling the amount of air flow of ammonia gas (for example, a gas mixer, a gas flow rate regulator, etc.).

On the other hand, water containing sodium thiosulfate (and sulfur denitrified sludge) is supplied as circulating water from the water supply tank 3 to the storage tank 4 via the pump 6 and then from the upper part of the deodorizing tank 2 via the pump 7. For example, about 3% of the volume of the deodorizing tank is sprinkled with circulating water once every 1 to several days (preferably 1 to 2 days, or 1 day if it is dry). Further, the circulating water is returned from the lower part of the deodorizing tank 2 to the storage tank 4.
The processing gas 8 can be discharged to the outside of the system from the upper part of the deodorizing tank 2.

The present invention described above has the following advantages over the prior art:
Unlike the method of diluting with water, the amount of water supply required does not increase and the amount of wastewater does not increase;
Since the denitrification tank is not provided separately, the equipment cost does not increase. By using the existing water tank as the sodium thiosulfate supply tank, it is possible to reduce the equipment cost;
Unlike the case of using an organic substance derived from a carrier or an organic waste that is a source of odor, it is possible to accurately grasp the amount of electron donor to be added, so that the control of the denitrification reaction is more accurate. Can be done;
Even if sodium thiosulfate is added in excess of the required amount, no separate wastewater treatment is required, so post-treatment after denitrification is not required;
Sulfur denitrifying bacteria are ubiquitous in the environment, and the growth rate of sulfur denitrifying bacteria is 0.051 / h in Thiobacillus thiophilus, for example (Kellermann and Griebler, 2009. International Journal of Systematic and Evolutionary Microbiology. 59: 583. -588.), It is relatively easy to prepare even if the bacterial cells need to be replenished;
It is not necessary to inhibit nitrate in the deodorizing tank, and the ion concentration can be easily controlled.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the technical scope of the present invention is not limited to these Examples.
1. 1. Materials and methods 1-1. Reactor operating conditions and ammonia removal performance evaluation Fig. 2 shows the outline of the reactor. A polycarbonate cylindrical reactor with a diameter of 7.5 cm and a height of 30 cm was filled with 0.8 L of deodorizing material. Rock wool (filler used in rock wool deodorization system (manufactured by Panasonic Environmental Systems &Engineering); including rice husks, zeolite, urethane chips; hereinafter referred to as "RW") and Otani stone powder (Otani stone grain (Otani stone material)) as deodorizing materials Cooperative); 2 to about 10 mm diameter, hereinafter referred to as "O") was used. For each of RW and O, a total of 4 treatment zones were set up with and without the addition of sulfur materials. As for the deodorizing material, sterilized distilled water was added in advance so that the water content at the time of filling was obtained, and then the activated sludge of the pig wastewater treatment facility by the batch type activated sludge method was resuspended in the nitrifying bacterium medium (Juhler et al. 2009). 12% (v / v) mixed. In a constant temperature room at 20 ° C, pure ammonia gas was diluted to about 100 ppm with an air compressor and aerated at about 0.4 L / min from the bottom. Circulating water (120 mL) was sprinkled from the top every few days to about 24 mL each time. Sterile distilled water was added up to a predetermined amount to replenish the reduced amount of circulating water before watering.

Two weeks after the equipment was started up, sludge accumulated under thiosulfate denitrification conditions was added to the circulating water in the sulfur material addition section. Thiosulfuric acid denitrification accumulated sludge is placed in a closed container so that the sulfur denitrification medium (Hashimoto et al. 1989) and the above activated sludge are 9: 1 (vol / vol), cultured at 28 ° C for 6 days, and then centrifuged. Recovered by. The disappearance of nitric acid and thiosulfate was confirmed during the culture, and 10 mL of the culture solution was used for each group. At the same time, sodium thiosulfate and trace metal element (Hashimoto et al. 1989) were added (in FIGS. 3 and 4 and Table 2, "+ S" means the addition of sodium thiosulfate and thiosulfate denitrified accumulated sludge). The amount of sodium thiosulfate added should be the required S / N ratio based on the following theoretical reaction formula for sulfur denitrification (Bisogni and Driscoll, 1977) with respect to the nitric acid concentration one week after the start of operation. I set it.

^{_{0.844 S 2 O 3 2- + NO}} 3 - + 0.347 CO 2 + 0.0865 HCO 3 - + 0.0865 NH 4 + + 0.434 H 2 O → 0.0865 C 5 H 7 O 2 N + 0.5 N 2 + 1.689 SO 4 2- + 0.697 H ⁺
Then added 4 times.

In order to evaluate the ammonia removal performance, a 3 mol / L sulfuric acid trap was attached to the final stage of the gas flow path in each treatment group to recover the effluent ammonia. A reactor that was not filled with materials was operated separately to grasp the inflow.

1-2. The circulating water before component analysis sprinkling of the circulating water to 0.1mL collected, glass electrode method pH (LAQUA twin pH meter, HORIBA) _{^{with, NH 4 +, NO 2 -}} , NO 3 -, S 2 O 3 2-, The SO ₄ ^2- concentration was measured by ion chromatography (HIC-NS, Shimadzu). The sulfuric acid solution trapped with ammonia was diluted and the ammonium concentration was measured by ion chromatography.

1-3. Microbial analysis of deodorant material On the 52nd day at the end of the test, the carrier was collected and the total DNA was extracted using the Fast DNA SPIN Kit for Soil (MO Bio). After purification using the QIAEX II Gel Extraction Kit (Qiagen), the DNA concentration was measured with the Fluorescent DNA Quantitation Kit (Bio-rad). Real-time PCR was performed under the following conditions using amoA-1F / amoA-2R (Rotthauwe et al. 1997), which is a primer specific to ammonia-oxidizing bacteria. Using a CFX96 real-time system (Bio-rad), a total of 20 μL reaction system containing 10 μL of 2 × SsoAdvanced universal SYBR Green supermix, 0.5 μM of primer, and 2.7 to 3.9 ng of template DNA was performed. As for the amplification conditions, after heat denaturation at 98 ° C. for 3 minutes, 98 ° C. for 15 seconds and 60 ° C. for 1 minute were performed in 40 cycles, and then melting curve analysis was performed in the range of 65 ° C. to 95 ° C. Calibration curves were prepared using known quantities of the amoA genes of Nitrosomonas multiformis (NCIMB 11849) and Nitrosomonas europaea (NBRC 14298). A known concentration of the amoA gene was added to the sample, the PCR inhibition rate was determined, and the number of amoA copies of the sample was corrected.

In addition, next-generation sequence analysis targeting the 16S rRNA gene of general bacteria was performed by the same method as Suto et al. (2017), and the presence of sulfur denitrifying bacteria was confirmed.

2. Results and discussion 2-1. Ammonia removal performance and changes in circulating water components The water content of the deodorizing material before use and during filling is 56% and 60%, 16% and 20% for RW and O, respectively. There were few.

Approximately 25.7 mg of ammonia nitrogen flowed in per day, but 99% or more was removed in all treatment groups (Fig. 3). A few days after the addition of sodium thiosulfate, a decrease in the concentration of nitrite and nitric acid in the circulating water was observed in Group O (Figs. 4a and 4b). In plot O, the decrease in nitric acid was accompanied by sulfuric acid production (Fig. 4e), suggesting that sulfur denitrification was occurring. At this time, the pH of the O group tended to be slightly lower than that without the addition of thiosulfate, and was significantly reduced especially in the latter half of the test period (Fig. 4d). On the other hand, in the RW group, the nitric acid production rate gradually decreased 18 days after the start of sodium thiosulfate addition (Fig. 4a). On the 27th day, a decrease in nitrite was observed (Fig. 4b), and the production of sulfuric acid was confirmed (Fig. 4e). Comparing the groups with and without sodium thiosulfate added to the inorganic nitrogen concentration in the circulating water on day 52, the addition of sodium thiosulfate reduced the concentrations of RW and O by 28% and 44%, respectively (Table). 1).

The following are possible reasons why the decrease in nitric acid and nitrite in the RW group was observed after the number of days after the addition of thiosulfate had passed. The nitrate reductase system of Thiobacillus denitrificans, a sulfur denitrifying bacterium, has been shown to be inhibited by nitrite (Baalsrud and Baalsrud, 1954), with an inhibitory concentration of 200 mg / L (Claus and Kutzner, 1985) or 150 mg /. There is a report of L (Oh et al. 2000). In the RW group, the nitrite concentration exceeded 200 mg / L one week after the addition of sodium thiosulfate, and continued to accumulate up to around 700 mg / L, suggesting that the sulfur denitrification reaction may have been inhibited. rice field. On the other hand, when the decrease in nitric acid concentration began, the nitrite concentration still remained at 600 mg / L or more, so factors other than inhibition of nitrite can be considered.

2-2. AmoA gene copy number derived from ammonia oxidizing bacteria microbes analysis deodorizing material, both RW Zone and O-ku, although ng was DNA per 10 ⁴ orders, 27% RW Ward by sulfur addition, 31% in O-ku reduced Was.

Looking at the changes in the ammonium concentration in the circulating water, the ammonium concentration remained high in the latter half of the test period, especially in the sulfur-added group in Group O, and a decrease in pH was observed as described above (Figs. 4c and 4d). ). A decrease in pH is thought to inhibit ammonia oxidation because it causes a decrease in the concentration of non-ionic ammonia, which is a form available to ammonia-oxidizing bacteria (Suzuki et al. 1974). Another test provided data suggesting the possibility of nitrogen removal without inhibiting nitrification by keeping the pH on the weakly alkaline side in a reactor filled with Oya stone (Table 2).

As a result of microbial analysis of the deodorizing material, the genus Thiobacillus containing sulfur denitrifying bacteria was detected only in the sodium thiosulfate-added group in both the RW group and the O group. In this test, as described above, sludge accumulated with sodium thiosulfate was inoculated, and it was judged that the inoculated bacteria were involved in the sulfur denitrification reaction in the deodorization test reactor.

The abundance ratio in each section of the Nitrosomonadale family, including the genus Nitrosomonas and the genus Nitrosospira, which are ammonia-oxidizing bacteria, showed a tendency similar to the number of copies of the amoA gene. In addition, it was suggested that the abundance ratio of the genus Nitrospira, which is a nitrite-oxidizing bacterium, was higher in the O group than in the RW group.

3. 3. Summary It has been clarified that in a circulating watering type biological deodorizing device, sulfur denitrification and nitrification can be combined to remove ammonia and suppress the accumulation of inorganic nitrogen in circulating water. Although sulfur denitrification reaction occurs in both rock wool and Oya stone, under the operating conditions of this example, the removal rate of inorganic nitrogen in circulating water is higher than that in the case of using rock wool with the combination of Oya stone and sodium thiosulfate. It was suggested that it could be further enhanced.

4. References
Baalsrud K. and Baalsrud KS (1954) Studies on Thiobacillus denitrificans. Arch. Mikrobiol. 20: 34-62.
Bisogni JJJr. And Driscoll CTJr. (1977) Denitrification using Thiosulfate and Sulfide, Proc. Of Am. Soc. Civ. Eng., J. Env. Eng. Div. 103: 593-604.
Claus G. and Kutzner HJ (1985) Physiology and kinetics of autotrophic denitrification by Thiobacillus denitrificans. Appl. Microbiol. Biotechnol. 22: 283-288.
Juhler S., Revsbech NP, Schramm A., Herrmann M., Ottosen LDM and Nielsen LP (2009) Distribution and rate of microbial processes in an ammonia-loaded air filter biofilm. Appl. Environ. Microbiol. 75: 3705-3713.
Kellermann C. and Griebler C. (2009) Thiobacillus thiophilus sp. Nov., A chemolithoautotrophic, thiosulfate-oxidizing bacterium isolated from contaminated aquifer sediments. Int. J. System. Evol. Microbiol. 59: 583-588.
Kruemmel and Heinz (1982) Effect of organic matter on growth and cell yield of ammonia-oxidizing bacteria. Arch. Microbiol. 133: 50-54.
Oh SE, Kim KS, Choi HC, Cho J. and Kim IS (2000) Kinetics and physiological characteristics of autotrophic denitrification by denitrifying sulfur bacteria. Water Sci. Technol. 42: 59-68.
Rotthauwe JH, Witzel KP and Liesack W. (1997) The ammonia monooxygenase structural gene amoA as a functional marker: molecular fine-scale analysis of natural ammonia-oxidizing populations. Appl. Environ. Microbiol. 63: 4704-4712.
Suto R., Ishimoto C., Chikyu M., Aihara Y., matsumoto T., Uenishi H., Yasuda T., Fukumoto Y. and Waki M. (2017) Anammox biofilm in activated sludge swine wastewater treatment plants. Chemosphere. 167: 300-307.
Suzuki I., Dular U. and Kwok SC (1974) Ammonia or ammonium as substrate for oxidation by Nitrosomonas europaea cells and extracts. J. Bacteriol. 120: 556-558.
Shou Hashimoto, Kenji Furukawa, Masahiko Shioyama (1989) Accumulation of sulfur denitrifying bacteria and adaptation to elemental sulfur. Water pollution research, 12, 431-440.

1: Deodorizing and denitrifying treatment device according to the present invention 2: Deodorizing tank 3: Water supply tank 4: Storage tank 5: Ammonia gas 6: Pump 7: Pump 8: Processing gas

Claims (8)

A deodorizing tank filled with Oya stone inoculated with activated sludge, which uses ammonia gas for nitrification and sulfur denitrification reactions.
A water supply tank that supplies water containing sodium thiosulfate to the deodorizing tank, and
A deodorizing and denitrifying treatment device equipped with
In the deodorizing tank, ammonia is nitrified by nitrifying bacteria in the active sludge grown on the surface of Otani stone in a state of being adsorbed on Otani stone, and converted to nitrite and nitric acid, while thiosulfate as a sulfur source. By adding sodium, a sulfur denitrification reaction occurs due to sulfur-oxidizing bacteria in active sludge, thiosulfate reacts with nitrite and nitric acid, and oxidation of thiosulfate produces sulfuric acid, which removes nitrogen as nitrogen gas. do,
The device . The device according to claim 1, wherein the ammonia gas is generated from the process of treating livestock excrement. The device according to claim 1 or 2, wherein the water further contains sulfur denitrifying sludge. The device according to any one of claims 1 to 3, wherein the pH of water is 7.0 to 8.8. A deodorizing and denitrifying treatment method comprising a step of subjecting ammonia gas to a nitrification reaction and a sulfur denitrification reaction in the presence of activated sludge-inoculated Otani stone and sodium thiosulfate .
In the above step, ammonia is nitrified by nitrifying bacteria in the active sludge grown on the surface of Otani stone in a state of being adsorbed on Otani stone and converted to nitrite and nitric acid, while sodium thiosulfate as a sulfur source. Is added to cause a sulfur denitrification reaction by sulfur-oxidizing bacteria in active sludge, thiosulfate reacts with nitrite and nitric acid, and oxidation of thiosulfate produces sulfuric acid, which removes nitrogen as nitrogen gas. ,
The method . The method of claim 5, wherein the ammonia gas is generated from the process of treating livestock excrement. The method of claim 5 or 6, wherein the reaction is further carried out in the presence of sulfur denitrifying sludge. The method according to any one of claims 5 to 7, wherein the reaction is carried out at pH 7.0 to 8.8.

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