Medium-high temperature anaerobic bacteria capable of increasing methane yield and relieving ammonia inhibition and application of medium-high temperature anaerobic bacteria

Abstract

The invention relates to the technical field of environmental biology, in particular to medium-temperature and high-temperature anaerobic bacteria for increasing methane yield and relieving ammonia inhibition and application of the medium-temperature and high-temperature anaerobic bacteria. The invention provides the Anaerobic zm02 with the strain number of CGMCC No.46069. The Anaerobic zm02 can obviously improve the organic matter degradation efficiency and the methane yield of an anaerobic digestion system, can effectively relieve ammonia inhibition, can be applied to fermentation treatment of wastes, and has a very good application prospect.

Description

Technical Field

[0001] The present invention relates to the field of environmental biotechnology, and in particular to medium- and high-temperature anaerobic bacteria capable of increasing methane production and alleviating ammonia inhibition, and applications thereof. Background Art

[0002] Kitchen waste refers to the waste generated in the daily life of residents and in food processing, catering services, unit catering and other activities. It has the characteristics of complex composition and easy decay. In addition to the limited environmental capacity, incineration and landfill treatment will also produce harmful gases such as dioxins, sulfur dioxide, and nitrogen oxides, causing secondary atmospheric pollution, or leachate causing soil and groundwater pollution. However, kitchen waste also has the characteristics of high water content and high organic matter content, with organic matter accounting for more than 80% of its dry matter content. This determines that in addition to "hazardous", kitchen waste also has the characteristics of "resource". Therefore, sustainable resource utilization technology and waste resource conversion are very important for the treatment of kitchen waste. At present, the main resource utilization method of kitchen waste is anaerobic digestion, which can recycle energy and achieve clean, green and low-carbon treatment of kitchen waste.

[0003] Due to the complexity of the composition of food waste, during the anaerobic digestion process, it often faces problems such as acidification and ammonia inhibition, resulting in low methane production, which seriously affects the efficiency of resource processing and increases a lot of industrial costs. Therefore, how to improve system stability and methane production efficiency is an urgent problem to be solved in the anaerobic biogas production of food waste. Given that anaerobic digestion is a multi-phase, multi-stage, and associated biochemical process led by a variety of microorganisms. Its stability depends on the multiple assimilation effects between different bacterial communities, and system instability is essentially the result of microbial metabolic disturbances. Bioaugmentation is a method of improving reactor performance by adding specialized microorganisms to the reactor system to improve specific functions in the system. Bioaugmentation technology has a good development prospect because it plays a significant role in promoting anaerobic digestion and has the advantages of simple operation and low cost. By adding functional microbial strains to the anaerobic fermentation system, the vitality and performance of the anaerobic fermentation system can be improved, and the purpose of alleviating ammonia inhibition and improving the efficiency of anaerobic biogas production can be finally achieved. Therefore, it is of great significance and application value to explore biological strains that can improve methane production and alleviate ammonia inhibition. Summary of the invention

[0004] In view of this, the technical problem to be solved by the present invention is to provide medium- and high-temperature anaerobic bacteria and applications thereof that can increase methane production and alleviate ammonia inhibition.

[0005] The present invention provides Anaerobic_zm02 with a deposit number of CGMCC No.46069.

[0006] The present invention provides a bacterial flora comprising the Anaerobic_zm02 described in 1 of the present invention.

[0007] The present invention provides a bacterial agent, which includes Anaerobic_zm02 described in the present invention or the bacterial flora described in the present invention and auxiliary materials.

[0008] Furthermore, the auxiliary materials include anti-minerals, vitamins, antibiotics, culture media, stabilizers, anti-flocculants, antioxidants and / or solid media.

[0009] Furthermore, the solid medium includes sawdust, peat soil, cottonseed hulls, bran, gypsum, sand and / or sucrose.

[0010] In the present invention, the bacterial agent includes a liquid bacterial agent and / or a solid bacterial agent, which is not limited in the present invention; the liquid bacterial agent includes the Anaerobic_zm02 described in the present invention and a liquid or liquid-soluble auxiliary material, and the auxiliary material can be a mineral, a vitamin, an antibiotic, a culture medium, a stabilizer, a deflocculating agent and / or an antioxidant, etc., which assist the reproduction or function of the Anaerobic_zm02; in a specific embodiment of the present invention, the bacterial agent is a liquid bacterial agent, which is obtained by expanding the culture medium of the Anaerobic_zm02, and the concentration of the liquid bacterial agent is at least 1×10 8 CFU / mL.

[0011] The Anaerobic_zm02 described in the present invention is obtained by sludge enrichment. Compared with other enriched bacterial species, it has a stronger ability to promote the degradation of organic matter and increase the production of biogas (the Anaerobic_zm02 described has no independent methane production ability, but plays an auxiliary role in methanogens), and also shows the ability to effectively alleviate ammonia inhibition.

[0012] The present invention provides the use of at least one of the following A) to C) in waste fermentation:

[0013] A) Anaerobic_zm02 of the present invention;

[0014] B), the bacterial flora of the present invention;

[0015] C) the bacterial agent of the present invention.

[0016] The present invention provides a method for waste fermentation, which comprises fermenting waste using at least one of the following a) to c):

[0017] a) Anaerobic_zm02 of the present invention;

[0018] b) the bacterial flora of the present invention;

[0019] c) The bacterial agent of the present invention.

[0020] Furthermore, the waste includes livestock and poultry manure or horn, agricultural waste and / or restaurant waste, which is not limited in the present invention. The strains described in the present invention participate in the treatment of the above waste under anaerobic conditions; in a specific embodiment of the present invention, the waste is restaurant waste, and the restaurant waste and activated sludge are degraded by organic matter through the action of the liquid bacterial agent, and biogas is generated during the degradation process, and ammonia inhibition can be relieved to increase the treatment efficiency.

[0021] In a specific embodiment of the present invention, the food waste and activated sludge are uniformly mixed at a VS ratio of 2:1, and then the liquid bacterial agent of the present invention is added for anaerobic fermentation, or the liquid bacterial agent of the present invention is added during the continuous anaerobic fermentation process to achieve the effect of strengthening anaerobic digestion and relieving ammonia inhibition. The bacterial concentration in the bacterial agent used is not less than 1×10 8 CFU / mL, in the specific embodiment of the present invention, 1×10 8 CFU / mL; the amount of the bacterial agent added is 15-20% of the total volume of the kitchen waste and activated sludge.

[0022] The present invention provides the use of at least one of the following I) to III) in degrading organic matter, assisting in increasing methane production and / or relieving ammonia inhibition:

[0023] 1) Anaerobic_zm02 of the present invention;

[0024] II), the bacterial flora of the present invention;

[0025] III), the bacterial agent of the present invention.

[0026] The present invention provides a product for degrading organic matter, assisting in increasing methane production and / or relieving ammonia inhibition, wherein the raw materials include at least one of the following i) to iii) and other functional substances that assist in methane production and / or relieve ammonia inhibition.

[0027] i) Anaerobic_zm02 of the present invention;

[0028] ii), the bacterial flora of the present invention;

[0029] iii) the bacterial agent of the present invention.

[0030] Further, the functional substances include but are not limited to compounds, nucleic acids and / or enzymes.

[0031] The present invention provides a method for degrading organic matter, increasing methane production and / or relieving ammonia inhibition, which comprises utilizing at least one of the following i) to iv):

[0032] i) Anaerobic_zm02 of the present invention;

[0033] ii), the bacterial flora of the present invention;

[0034] ii), the bacterial agent of the present invention;

[0035] iv) The product of the present invention.

[0036] The present invention provides Anaerobic_zm02 with a strain number of CGMCC No.46069, which can significantly improve the organic matter degradation efficiency and methane production of an anaerobic digestion system, and can effectively alleviate ammonia inhibition, and can be used in the fermentation treatment of wastes, and has a good application prospect.

[0037] Biological Deposit Description

[0038] The biological material Anaerobic_zm02, classified and named: Schnuerera sp., was deposited on July 29, 2024 at the General Microbiology Center of China Culture Collection Administration, located at: Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, with the deposit number CGMCC No.46069. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a scanning electron micrograph of strain Anaerobic_zm02;

[0040] Figure 2 This is the neighbor-joining phylogenetic tree of strain Anaerobic_zm02;

[0041] Figure 3 The gas production and organic matter conversion rate of anaerobic digestion of food waste by strain Anaerobic_zm02, where a is the change of gas production in anaerobic digestion; b is the improvement of gas production and organic matter conversion rate (VS removal efficiency);

[0042] Figure 4 The results show that strain Anaerobic_zm02 alleviates ammonia inhibition (external ammonia nitrogen concentration is 2000 and 5000 mg / L) in anaerobic digestion of food waste, where a is the cumulative gas production; b is the remaining VS after the reaction is completed;

[0043] Figure 5The results show that strain Anaerobic_zm02 alleviates ammonia inhibition (external ammonia nitrogen (TAN) concentrations of 1000 and 3000 mg / L) in anaerobic digestion of food waste, where a is the cumulative gas production; b is the VS remaining after the reaction is completed;

[0044] Figure 6 Figure 3 shows the alleviation of ammonia inhibition by strain Anaerobic_zm02 in anaerobic digestion of food waste at medium temperature, medium-high temperature and high temperature. a is the alleviation of ammonia inhibition in anaerobic digestion of food waste at medium temperature; b is the alleviation of ammonia inhibition in anaerobic digestion of food waste at medium-high temperature; c is the alleviation of ammonia inhibition in anaerobic digestion of food waste at high temperature. DETAILED DESCRIPTION

[0045] The present invention provides medium- and high-temperature anaerobic bacteria and their applications for increasing methane production and alleviating ammonia inhibition. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters for implementation. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0046] The present invention provides a strain for enhancing the anaerobic digestion of food waste to produce methane, which is identified as Schnuererasp., preserved in the China General Microbiological Culture Collection Center (CGMCC), the strain name is Anaerobic_zm02, and the preservation number is CGMCC No. 46069. The preservation address is No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing; the Anaerobic_zm02 is a Gram-positive bacterium, strictly anaerobic.

[0047]

[0048] In the present invention, the Anaerobic_zm02 is separated and screened from the activated sludge of a continuously operating kitchen waste anaerobic reactor (Hangzhou Energy and Environmental Engineering Co., Ltd.).

[0049] In some laboratory experiments, anaerobic activated sludge and food waste were evenly mixed at a VS ratio of 2:1 and placed in a 500 mL anaerobic bottle with a working volume of 200 mL. The bacterial agent was inoculated at 10% of the total volume for anaerobic fermentation (the bacterial agent was taken at 15% of the working volume in the system, centrifuged, and the bacterial precipitate was resuspended with 1 / 10 volume of sterile water of the bacterial solution, and the bacterial suspension was inoculated into the anaerobic fermentation system and cultured at 45 °C until the system no longer produced gas, which could increase the organic matter conversion rate by 14.56% and the cumulative gas production by 17.63%.

[0050] In other laboratory experiments, the effect of strain Anaerobic_zm02 on mitigating ammonia inhibition in the anaerobic fermentation of wet food waste at medium and high temperatures (45 °C) was verified. By adding NH4Cl, the concentration of added ammonia nitrogen reached 1000 mg / L, 2000 mg / L, 3000 mg / L, and 5000 mg / L, respectively. The experimental group added bacterial agents at 15% of the system working volume. When the organic load was 5 g VS / Ld, the cumulative methane production of the experimental group increased by 29.08%, 16.89%, 13.00%, and 20.26% respectively compared with the control group.

[0051] In a continuously running 30 L anaerobic fermentation tank, the strain Anaerobic_zm02 was verified to alleviate ammonia inhibition during the anaerobic fermentation of food waste at medium temperature, medium-high temperature, and high temperature. The reactor was brought into an ammonia inhibition state (methane production was reduced by more than 20% compared with Blank) by adding NH4Cl, and then the bacterial agent was added at 20% of the system working volume. At medium temperature, medium-high temperature, and high temperature, the average methane production after adding the bacterial agent increased by 24.08%, 28.58%, and 17.66% respectively compared with the inhibition state.

[0052] The use of the high-efficiency anaerobic methanogenic agent provided by the present invention can improve the organic matter removal rate, increase the methane production, and effectively alleviate the impact of ammonia inhibition on gas production, save equipment and investment and operation costs, and have good economic and environmental benefits.

[0053] The test materials used in the present invention are all common commercial products and can be purchased on the market. The present invention is further described below in conjunction with the embodiments:

[0054] Example 1 Isolation and screening of anaerobic digestion functional bacteria

[0055] 1. The formula of Modified Wolin medium used in the example is as follows:

[0056] Modified Wolin's mineral solution 1 (MWL1, Modified Wolin basal medium): KCl 0.34 g / L, MgCl2·6H2O 4.00 g / L, MgSO4·7H2O 3.45 g / L, NH4Cl 0.25 g / L, CaCl2·2H2O 0.14 g / L, K2HPO4 0.14 g / L, NaCl 18.00 g / L, Modified Wolin's mineral solution10.00 mL, Fe(NH4)2(SO4)2·6H2O (0.1% w / v) 2.00 mL, Na-acetate 1.00 g / L, Yeastextract 2.00 g / L, Trypticase peptone 2.00 g / L, Sodium resazurin (0.1% w / v) 1mL, NaHCO3 5.00 g / L, Wolin's vitamin solution 10.00 mL, L-Cysteine ​​HCl·H2O 0.50g / L, Na2S·9H2O 0.50 g / L, Distilled water 1000.00 mL.

[0057] Wolin's vitamin solution (Wolfe's vitamin solution): Biotin 2.00 mg / L, Folicacid 2.00 mg / L, Pyridoxine hydrochloride 10.00 mg / L, Thiamine HCl 5.00 mg / L, Riboflavin 5.00 mg / L, Nicotinic acid 5.00 mg / L, Calcium D-(+)-pantothenate 5.00mg / L, Vitamin B12 0.10 mg / L, p-Aminobenzoic acid 5.00 mg / L, (DL)-alpha-Lipoic acid 5.00 mg / L, Distilled water 1000.00 mL.

[0058] Modified Wolin's mineral solution:Nitrilotriacetic acid 1.50 g / L,MgSO4·7H2O 3.00 g / L,MnSO4 ·H2O 0.50 g / L,NaCl1.00 g / L,FeSO4·7 H2O 0.10 g / L,CoSO4·7H2O 0.18 g / L,CaCl2·2H2O 0.10 g / L,ZnSO4·7H2O 0.18 g / L,CuSO4·5H2O 0.01 g / L,AlK(SO4)2·12H2O 0.02 g / L,H3BO3 0.01g / L,Na2MoO4·2H2O 0.01 g / L,NiCl2·6H2O 0.03 g / L,Na2SeO3·5H2O 0.30 mg / L, Na2WO4·2H2O 0.40 mg / L, Distilled water 1000.00 mL.

[0059] Modified Wolin basal medium was added with modified Wolfe's mineral solution (10 mL / L Modified Wolin basal medium), sterilized by high pressure steam at 121°C for 20 min, and then filtered and sterilized Wolfe's vitamin solution (10 mL / L Modified Wolin basal medium) was added to obtain Modified Wolin medium for use.

[0060] The anaerobic sludge used to isolate functional bacteria was collected from the long-term anaerobic digestion reactor of Hangzhou Energy and Environmental Engineering Co., Ltd. in Hangzhou, Zhejiang Province. 10 mL of anaerobic sludge was inoculated into 200 mL of Modified Wolin medium and enriched at 45 °C and 200 rpm for 7 days. Another 10 mL of culture medium was transferred to a new Modified Wolin medium and a second round of enrichment culture was carried out at 45 °C and 200 rpm. After 7 days, the enriched culture medium was gradient diluted, and the dilution was 10 -3 , 10 -4 , 10 -5 and 10 -6The enriched culture fluid was evenly spread on a solid plate of Modified Wolin medium (15-20g agar was added to Modified Wolin medium), and a single colony was picked after 48-96 hours of constant temperature culture at 44°C. The single colony was inoculated into Modified Wolin liquid medium, and after three times of culture-streaking-purification-passaging, the strain was determined by 16S rRNA sequencing. After testing, the strain had a similarity of 97.34% with Schnuerera ultunensis (the basal synonym is Clostridium ultunense), and its scanning electron micrograph is shown in the figure below. Figure 1 , the phylogenetic tree is as follows Figure 2 The bacterial solution was mixed with 50% glycerol at a ratio of 1:1 and stored at -80°C.

[0061] Example 2 Preparation of bacterial agent of bacterial strain

[0062] The pure strain of Anaerobic_zm02 was inoculated into 15 mL of Modified Wolin medium and cultured anaerobically at 45 °C and 200 rpm for 24-48 h. Then, it was inoculated into the next level of Modified Wolin medium at an inoculum rate of 1% of the volume of the Modified Wolin medium. The liquid inoculum of the strain was obtained by continuing to expand the culture under the same conditions.

[0063] Example 3: Enhanced effect of bacterial agent on gas production from wet anaerobic digestion of food waste

[0064] The food waste was taken from the food waste slurry of Xiaoshan Food Waste Treatment Plant, with a total solids (TS) content of 6.33% and a VS (volatile solid) / TS ratio of 81.03%. The activated sludge was collected from the long-term anaerobic digestion reactor of Hangzhou Energy and Environmental Engineering Co., Ltd. in Hangzhou, Zhejiang Province, with a TS content of 10.754% and a VS / TS ratio of 30.033%.

[0065] The food waste and activated sludge were evenly mixed at a VS ratio of 1:2 and placed in a 500 mL anaerobic bottle with a working volume of 200 mL and an organic load of 7.5 g VS / L. Experimental and control groups were set up. The experimental group was inoculated with liquid inoculant at 15% of the total volume of food waste and anaerobic activated sludge (the inoculant was taken at 15% of the total volume of the system (the concentration was at least 1×10 8CFU / mL), centrifuged, resuspended the bacterial precipitate with 1 / 10 volume of sterile water, and inoculated the bacterial suspension into the anaerobic fermentation system), the control group added the same volume of sterile water instead of the bacterial agent, the blank group was a single anaerobic activated sludge, and sterile water was added to all three groups to make the final working volume 200 mL. The temperature was controlled at 45 ℃, the biogas production was tested every day, and the VS in each system was measured before and after fermentation. The results showed (such as Figure 3 ), the cumulative gas production of the experimental group was 956.3 mL, which was 17.63% higher than that of the control group (813.0 mL). At the same time, the organic matter conversion rate of the experimental group was 82.10%, which was 14.56% higher than that of the control group (71.67%). This indicates that the strain Anaerobic_zm02 has a significant strengthening effect on the anaerobic fermentation of kitchen waste to produce biogas under medium and high temperature conditions.

[0066] Among them, organic matter conversion rate = [(VS (底物) )-(VS (1) -VS (污泥1) )] / (VS (0) -VS (污泥0) )×100%

[0067] VS (底物) : Volatile solid content of the food waste substrate added to the system (g);

[0068] VS (1) : Volatile solid content at the end of fermentation of the fermentation system containing food waste substrate and anaerobic activated sludge (g);

[0069] VS (污泥1) : Volatile solid content (g) at the end of fermentation in a single anaerobic activated sludge fermentation system.

[0070] Example 4 Effect of bacterial agents on alleviating ammonia stress in high-temperature wet anaerobic fermentation of food waste (external ammonia nitrogen concentration of 2000 and 5000 mg / L)

[0071] The food waste was taken from the food waste slurry of Xiaoshan Food Waste Treatment Plant, and the TS content of the food waste slurry was 6.33%, and the VS / TS was 81.03%. The activated sludge was collected from the long-term anaerobic digestion reactor of Hangzhou Energy and Environmental Engineering Co., Ltd. in Hangzhou, Zhejiang Province, and the TS content of the activated sludge was 8.764%, and the VS / TS was 30.596%.

[0072] The food waste and activated sludge were uniformly mixed at a VS ratio of 1:2, with a working volume of 200 mL and a total organic load of 5 g VS / L. Two ammonia nitrogen concentrations were set by adding NH4Cl to simulate the ammonia inhibition encountered in the anaerobic digestion of food waste. The concentrations of added NH4Cl were: (1) 2000 mg / L; (2) 5000 mg / L. A control group and an experimental group were set for each concentration gradient. The experimental group was inoculated with liquid bacterial agent at 15% of the total volume of food waste and anaerobic activated sludge (the bacterial agent was taken at 15% of the total volume of the system, centrifuged, and the bacterial precipitate was resuspended with 1 / 10 volume of sterile water of the bacterial liquid, and the bacterial suspension was inoculated into the anaerobic fermentation system). The control group added the same volume of sterile water instead of the bacterial agent. Finally, sterile water was added to make the working volume of the experimental group and the control group 200 mL. Three replicates were set for each treatment. The temperature was controlled at 45 °C, the biogas production was detected every day, and the VS in each system was measured before and after fermentation to calculate the utilization of organic matter. The results showed (such as Figure 4 ), when the concentration of added ammonia nitrogen was 2000 mg / L, the average cumulative gas production of the experimental group was 715.0 mL, which was 16.89% higher than the cumulative gas production of 611.7 mL in the control group. At the same time, the amount of residual organic matter (in terms of VS) decreased by 16.28% compared with the control group. When the concentration of added ammonia nitrogen was 5000 mg / L, the cumulative gas production of the experimental group was 672.6 mL, which was 20.26% higher than the cumulative gas production of 559.3 mL in the control group. At the same time, the amount of residual organic matter (in terms of VS) decreased by 6.37% compared with the control group.

[0073] Example 5 Effect of bacterial agents on alleviating ammonia stress in high-temperature wet anaerobic fermentation of food waste (external ammonia nitrogen concentrations of 1000 and 3000 mg / L)

[0074] The food waste was taken from the food waste slurry of Xiaoshan Food Waste Treatment Plant, and the TS content of the food waste slurry was 5.071%, and the VS / TS was 76.261%. The activated sludge was collected from the long-term anaerobic digestion reactor of Hangzhou Energy and Environmental Engineering Co., Ltd. in Hangzhou, Zhejiang Province, and the TS content of the activated sludge was 7.817%, and the VS / TS was 27.311%.

[0075] The food waste and activated sludge were uniformly mixed at a VS ratio of 1:2, with a working volume of 100 mL and a total organic load of 5 g VS / L. Two ammonia nitrogen concentrations were set by adding NH4Cl to simulate the ammonia inhibition encountered in the anaerobic digestion of food waste. The concentrations of added NH4Cl were: (1) 1000 mg / L; (2) 3000 mg / L. A control group and an experimental group were set for each concentration gradient. The experimental group was inoculated with liquid bacterial agent at 15% of the total volume of food waste and anaerobic activated sludge (the bacterial agent was taken at 15% of the total volume of the system, centrifuged, and the bacterial precipitate was resuspended with 1 / 10 volume of sterile water of the bacterial liquid, and the bacterial suspension was inoculated into the anaerobic fermentation system). The control group added the same volume of sterile water instead of the bacterial agent. Finally, sterile water was added to make the working volume of the experimental group and the control group 100 mL. Three replicates were set for each treatment. The temperature was controlled at 45 °C, the biogas production was detected every day, and the VS in each system was measured before and after fermentation to calculate the utilization of organic matter. The results showed (such as Figure 5 ), when the added ammonia nitrogen concentration was 1000 mg / L, the average cumulative gas production of the experimental group was 651.0 mL, which was 29.08% higher than the cumulative gas production of 504.3 mL in the control group. At the same time, the amount of residual organic matter (in terms of VS) decreased by 7.25% compared with the control group. When the added ammonia nitrogen concentration was 3000 mg / L, the cumulative gas production of the experimental group was 336.0 mL, which was 13.00% higher than the cumulative gas production of 297.3 mL in the control group. At the same time, the amount of residual organic matter (in terms of VS) decreased by 7.85% compared with the control group.

[0076] Example 6 Effect of bacterial agents on alleviating ammonia stress in medium-temperature, medium-high-temperature, and high-temperature wet anaerobic fermentation of food waste

[0077] The food waste was collected from the food waste slurry of Xiaoshan Food Waste Treatment Plant; the activated sludge was collected from the long-term anaerobic digestion reactor of Hangzhou Energy and Environmental Engineering Co., Ltd. in Hangzhou, Zhejiang Province. The physical and chemical properties of the activated sludge and food waste used in the operation of the reactor are shown in Table 1.

[0078] Table 1. Physicochemical properties of food waste and activated sludge

[0079]

[0080] This experiment was carried out in a completely stirred anaerobic digestion reactor with a working volume of 30 L. According to the VS calculation of the food waste slurry, the organic loading rate of the reactor was controlled to be 2.1 g / (L·d) -1. The feed is fed and discharged from the top feed port once a day, and the generated gas is discharged through the exhaust port. The gas volume is measured by the gas flowmeter connected to the exhaust port. Three reactors (M, MH, H) with medium temperature, medium-high temperature, and high temperature are set up for anaerobic fermentation at 37 ℃, 45 ℃, and 55 ℃, respectively, and the generated gas volume is recorded every day. At the same time, indicators such as methane content, pH, and ammonia nitrogen concentration in biogas are monitored.

[0081] After the gas production of the reactor is stable (recorded as Blank), the ammonia nitrogen concentration of the system is adjusted by adding NH4Cl solid. The ammonia nitrogen concentration is increased in a gradient, so that the anaerobic digestion system at the three temperatures finally reaches the ammonia inhibition state. That is, first make the concentration of added ammonia nitrogen reach 1000 mg / L, and continue for 5 to 7 days. Pay attention to indicators such as methane production. If the methane production drops to 20% of the stable stage (Blank), stop increasing the concentration of added ammonia nitrogen and enter the bio-enhancement stage; if the methane production does not drop significantly, continue to add NH4Cl solid to increase the concentration of added ammonia nitrogen in the system. The ammonia nitrogen concentration of each gradient is increased by 500 mg / L compared with the previous gradient. After entering the bio-enhancement stage, inoculate liquid bacterial agent (concentration of at least 1×10 8 CFU / mL. Take the inoculum at 20% of the total volume of the system, centrifuge, resuspend the bacterial precipitate with 1 / 10 volume of sterile water, inoculate the bacterial suspension into the reactor, pay attention to indicators such as methane production, so as to verify the effect of adding the inoculum on alleviating ammonia inhibition of anaerobic digestion at different temperatures.

[0082] The results are as follows Figure 6 As shown in the figure, when the concentration of ammonia nitrogen added was 2500 mg / L, the average methane production of the reactor operated at medium temperature decreased by 28.07%, and the average methane production after adding the bacterial agent increased by 24.08% compared with the inhibition state; when the concentration of ammonia nitrogen added was 3000 mg / L, the average methane production of the reactor operated at medium and high temperature decreased by 20.13%, and the average methane production after adding the bacterial agent increased by 28.58% compared with the inhibition state; when the concentration of ammonia nitrogen added was 2500 mg / L, the average methane production of the reactor operated at high temperature decreased by 36.40%, and the average methane production after adding the bacterial agent increased by 17.66% compared with the inhibition state. This shows that the bacterial agent has an outstanding effect in alleviating ammonia inhibition.

[0083] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. Anaerobic_zm02 with the deposit number of CGMCC No.46069.

2. A flora, characterized in that Including Anaerobic_zm02 as described in claim 1.

3. A bacterial agent, characterized in that It comprises the Anaerobic_zm02 described in claim 1 or the flora described in claim 2 and auxiliary materials.

4. The bacterial agent according to claim 3, characterized in that The auxiliary materials include anti-minerals, vitamins, antibiotics, culture media, stabilizers, anti-flocculants, antioxidants and / or solid media.

5. Application of at least one of the following A) to C) in waste fermentation: A) and the Anaerobic_zm02 described in the claims; B), the bacterial flora according to claim 2; C) The bacterial agent according to claim 3 or 4.

6. The use according to claim 5, characterized in that: The waste includes food waste.

7. A method for waste fermentation, characterized in that: The method comprises fermenting waste using at least one of the following a) to c): a) Anaerobic_zm02 as described in the claims; b) The bacterial flora according to claim 2; c) The bacterial agent according to claim 3 or 4.

8. Use of at least one of the following I) to III) in degrading organic matter, assisting in increasing methane production and / or relieving ammonia inhibition: I) Anaerobic_zm02 as described in the claim; II), the bacterial colony according to claim 2; III), the bacterial agent according to claim 3 or 4.

9. A product for degrading organic matter, assisting in increasing methane production and / or relieving ammonia inhibition, characterized in that: The raw materials include at least one of the following i) to iii) and other functional substances that assist in the degradation of organic matter, increase methane production and / or relieve ammonia inhibition: i) Anaerobic_zm02 as described in the claims; ii) The bacterial flora according to claim 2; iii) The bacterial agent according to claim 3 or 4.

10. A method for degrading organic matter, increasing methane production and / or relieving ammonia inhibition, characterized in that: Including using at least one of the following i) to iv): i) Anaerobic_zm02 as described in the claims; ii) The bacterial flora according to claim 2; iii) the bacterial agent according to claim 3 or 4; iv) The product according to claim 9.

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