Method for rapidly producing organic fertilizer from organic waste by strain ecological method

Abstract

The invention discloses a method for rapidly producing an organic fertilizer from organic wastes by a strain ecological method and a microbial composition used in the method, and belongs to the technical field of organic waste treatment. The method aims to solve the problems of serious nitrogen volatilization loss, low functional flora synergistic efficiency and insufficient product decomposition degree in the fermentation process in the prior art. According to the method, a multi-component product is adopted and comprises a signal slow release type functional carrier (composition A) loaded with microbial population sensing signal molecules, a hydrolysis starting period fungicide (composition B), a signal response type thermophilic fungicide (composition C) and a decomposition synergistic period fungicide (composition D). Firstly, the composition A is mixed with organic waste, and then the compositions B, C and D are added in a sequencing batch mode according to the stage sequence of hydrolysis, high temperature and decomposition. According to the method disclosed by the invention, a microbial ecological system combining signal regulation and time sequence inoculation is constructed, so that the nitrogen loss is remarkably reduced, the quality and the decomposition degree of the organic fertilizer are improved, and the fermentation period is shortened.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic waste treatment, in particular to a method for rapidly producing organic fertilizer from organic waste by a strain ecological method. BACKGROUND

[0002] Organic waste resource utilization is an important part of environmental technology. Among many treatment methods, microbial aerobic fermentation technology is one of the mainstream processes for converting organic waste into organic fertilizer. This technology is widely used in the treatment of municipal solid waste, agricultural straw, and livestock and poultry manure, aiming to achieve harmless disposal and resource recycling of waste.

[0003] However, conventional aerobic fermentation technology has inherent technical bottlenecks in application. During the high-temperature stage of fermentation, organic nitrogen in the material is quickly mineralized into ammonia. The combined action of high temperature and alkaline environment immediately triggers intense ammonia volatilization. This directly leads to a large loss of nitrogen nutrients in the final product. In addition, the start-up period of fermentation is a critical window for microbial competition. Putrefactive microorganisms easily proliferate, not only producing malodorous substances, but also inhibiting the establishment of the dominant position of beneficial functional flora. The existing microbial inoculant addition method is mostly one-time input at the beginning of fermentation. This mode ignores the specific requirements of different functional microorganisms for environmental conditions and action timing. The suitable temperature intervals of mesophilic bacteria and thermophilic bacteria conflict, and the timing of nitrogen fixation should also match the peak period of ammonia nitrogen generation. One-time inoculation cannot achieve this timing coupling. The lack of such spatiotemporal coordination limits the operating efficiency of the entire fermentation system. Therefore, the final product often has the problem of incomplete composting, which may contain substances toxic to plants, which together restrict the quality improvement and efficient production of organic fertilizer. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a method for rapidly producing organic fertilizer from organic waste by a strain ecological method, which solves the problems of severe nitrogen loss during the high-temperature stage of fermentation, low synergy efficiency of functional flora, and insufficient composting degree of the final product in the prior art.

[0005] To achieve the above purpose, the present application is implemented by the following technical solutions: The present application provides, in a first aspect, a microbial composition product for organic waste fermentation, which is composed of multiple compositions that are independent of each other in function and addition timing. This multi-composition system, through the synergistic action of its internal components, can orderly regulate the entire process of organic waste fermentation.

[0006] In one specific embodiment, the microbial composition product comprises at least the following four independent compositions: composition A, composition B, composition C, and composition D.

[0007] The composition A is a signal slow-release functional carrier, the core function of which is to provide a microorganism with a colonization microdomain, pre-adsorb part of the to-be-converted substance, and serve as a signal release source for the subsequent initiation of specific microbial functions. In terms of dry weight, the composition comprises 40%-60% mesoporous biochar, 20%-30% zeolite powder, 5%-15% potassium humate, and 1%-5% chitosan. In addition to the above components, the carrier also carries a pre-set, non-fermentation environment endogenous microbial quorum sensing signal molecule. In one embodiment, the signal molecule is an N-acyl homoserine lactone (AHL) type signal molecule.

[0008] In a specific embodiment, the preparation method of the composition A (signal slow-release functional carrier) comprises the following steps: Signal molecule loading: dissolve the N-acyl homoserine lactone signal molecule in an organic solvent (ethanol) to form a signal solution; uniformly spray the signal solution on the mixture of pre-weighed mesoporous biochar and zeolite powder, and continuously stir at a specific temperature (room temperature or slightly heated) until the solvent is completely volatilized, so that the signal molecule is loaded inside the porous carrier material through physical adsorption.

[0009] Dry powder mixing: uniformly mix the carrier material loaded with the signal molecule and the potassium humate powder in a mixing device.

[0010] Binder preparation and granulation: dissolve the chitosan in a weak acid solution (1% acetic acid solution) to prepare a binder solution with a specific viscosity; place the above dry mixed powder in a granulation device, knead by spraying or dripping the chitosan binder solution, and prepare wet granules with a specific particle size (2-5 mm) by extrusion or rolling.

[0011] Drying: dry the prepared wet granules at low temperature (below 40°C) by air flow drying or vacuum drying until the water content is below the pre-set value (10%), and the composition A product is obtained.

[0012] The composition B is a hydrolysis initiation period composite microbial agent, which is used in the initial stage of the fermentation process.

[0013] The composition C is a signal response type thermophilic composite microbial agent, which is used in the high temperature stage of the fermentation process.

[0014] The composition D is a decomposition and synergism period composite microbial agent, which is used in the cooling and decomposition stage of the fermentation process.

[0015] In order to realize the cooperation of microbial populations at each stage and the stable operation of the system, the present application further limits the above-mentioned compositions.

[0016] The signal-responsive nitrifying functional strain contained in the composition C has its nitrification metabolic pathway initiated under the control of the pre-set microbial quorum sensing signal molecule in the composition A. When the signal molecule is released from the composition A and reaches the set concentration threshold, it can specifically induce the expression of the genes encoding the key enzymes of the nitrification metabolism in the strain, thereby initiating its nitrification function. This structure establishes the functional connection between the composition A and the composition C.

[0017] In addition, there are also interactions between the bacterial agent compositions at the level of metabolites. In one embodiment, the microorganisms in the composition B can produce specific bacitracin in their metabolic processes. The bacitracin has an inhibitory effect on common spoilage microorganisms in the fermentation material, but does not significantly inhibit the functional strains in the subsequently added compositions C and D, thereby establishing a favorable microbial niche for the growth and succession of the dominant functional bacterial population. In another embodiment, the microorganisms in the composition C can produce specific growth factors in their metabolic processes, which are precursor substances required for the growth of some functional strains (photosynthetic bacteria) in the composition D, and can promote their proliferation and function in the composting stage. This structure establishes the metabolic flow connection between the compositions B, C and D.

[0018] The second aspect of the present application provides a method for rapidly producing organic fertilizer from organic waste by microbial ecological method, which utilizes the above-mentioned microbial composition product and realizes efficient conversion of organic waste by staged and programmed regulation of the fermentation process.

[0019] The method comprises the following steps: a) mixing the organic waste with the aforementioned composition A to construct a fermentation initial material containing a signal release source and a microbial colonization microdomain; b) sequentially adding the aforementioned compositions B, C and D to the fermentation initial material or its subsequent fermentation product in a sequencing batch mode according to a pre-set time sequence, guiding the fermentation process to orderly go through three stages of hydrolysis initiation, high-temperature thermophilic and composting synergism with different functional and environmental conditions.

[0020] In a specific embodiment, the operation process and mechanism of step b) are as follows: First, in the initiation stage of the fermentation process (temperature controlled at 30-45°C), the composition B is added. The microorganisms in this composition mainly perform the hydrolysis function of the macromolecular organic matters such as proteins and cellulose in the waste. At the same time, as mentioned above, the bacitracin produced in its metabolism can form competitive inhibition to the spoilage bacteria in the system, ensuring that the fermentation proceeds in the predetermined direction.

[0021] Secondly, when the fermentation process enters the high temperature stage (temperature control at 55-65℃), composition C is added. The thermophilic strains in the composition produce heat rapidly to raise the material temperature to the set range, achieving harmless treatment of pathogenic bacteria and insect eggs. During this period, the organic nitrogen in the material is mineralized to produce ammonia or ammonium ions. With the continuous release of the pre-set signal molecules in composition A, when the concentration reaches the induction threshold, the nitrification function of the signal-responsive nitrifying functional strain in composition C is activated, converting the ammonia or ammonium ions into non-volatile nitrate nitrogen in situ within the fermentation system. The nitrate nitrogen can be adsorbed on the carrier, thereby significantly reducing the loss of nitrogen due to high temperature.

[0022] Finally, during the cooling and composting stage after the fermentation temperature falls from high temperature (temperature naturally cools below 45℃), composition D is added. The functional strains in the composition perform the final composting of the material. In one embodiment, the proliferation of specific functional strains (photosynthetic bacteria) in composition D is promoted due to the supply of metabolic products (specific growth factors) of composition C, thereby enhancing their degradation ability of residual antibiotic pollutants in the material or promoting the function of heavy metal passivation strains, ultimately obtaining high-quality organic fertilizer products.

[0023] The present application provides a method for rapidly producing organic fertilizer from organic waste by microbial ecological method. The method has the following beneficial effects: 1. The present application constructs a "signal induction-nitrogen fixation in situ" technical path by pre-setting signal molecules in the functional carrier (composition A) and adding nitrifying functional strains (composition C) that respond to the signal molecules during the high temperature stage. This path can timely and efficiently convert volatile ammonia nitrogen into stable nitrate nitrogen during the high temperature period when a large amount of ammonia is produced by organic nitrogen mineralization, and the nitrogen is adsorbed by the carrier, thereby significantly reducing the nitrogen loss during the fermentation process and effectively improving the total nitrogen content and fertilizer value of the final organic fertilizer product.

[0024] 2. The present application uses a method of sequentially adding functionally independent microbial compositions (compositions B, C, and D) to program the fermentation process. In the start-up stage, the bacitracin produced by composition B inhibits spoilage bacteria, establishing a dominant ecological niche for the growth of subsequent functional bacterial groups, ensuring the directionality and stability of the fermentation process, and avoiding the problem of material spoilage or rancidity caused by disordered microbial competition.

[0025] 3, The application utilizes the signal slow-release functional carrier (composition A) to construct a functional microdomain in the fermentation system. The carrier not only provides a place for microbial colonization and adhesion, but more importantly, as a controllable signal release source, it realizes the remote and timed start of the specific metabolic function (nitrification) of specific microorganisms (nitrifying bacteria in composition C). This precise spatiotemporal control enables the biological nitrogen fixation process, which is difficult to carry out efficiently at high temperatures, to be realized, thereby improving the overall synergistic efficiency of the system.

[0026] 4, The application improves the maturity and safety of the final product through the metabolic flow synergy between different stage microbial compositions. The metabolic products of composition C can provide specific growth factors for the functional strains in composition D, promoting their proliferation and function in the late decomposition stage, thereby more thoroughly decomposing residual organic matter and potential biological inhibitors, and ultimately obtaining an organic fertilizer product with a higher seed germination index (GI) and no toxic side effects on plant growth.

[0027] 5, The application divides the entire complex fermentation process into three functionally clear stages: hydrolysis initiation, high-temperature thermophilic, and decomposition efficiency enhancement, and matches each stage with a special microbial composition. This modular design enables each functional flora to perform at its maximum efficiency under the most suitable environmental conditions, improving the overall conversion rate of organic waste, shortening the fermentation period, and enhancing the universality and robustness of the technical solution for different sources and components of organic waste raw materials. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The figure is a schematic diagram of the method of the application. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the application will be described in detail below with reference to the drawings of the application specification. Obviously, the described embodiments are only a part of the embodiments of the application, not all. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the application.

[0030] Example 1: Preparation of composition A (signal slow-release functional carrier) This embodiment specifically describes the preparation process of composition A, which is one of the core components of the microbial composition product.

[0031] Raw material list: Mesoporous biochar: purchased from a commercial supplier, with bamboo-derived biochar as raw material, particle size of 100-200 mesh, specific surface area of 350 m 2 / g.

[0032] Zeolite powder: purchased from commercial suppliers, natural clinoptilolite, particle size 200 mesh.

[0033] Potassium humate: purchased from commercial suppliers, mineral origin, water-soluble 95%.

[0034] Chitosan: purchased from commercial suppliers, raw material from shrimp and crab shells, degree of deacetylation 90%.

[0035] Quorum sensing signal molecule: N-(3-oxohexanoyl)-L-homoserine lactone (3-oxo-C6-HSL), purity ≥98%, purchased from Sigma-Aldrich.

[0036] Preparation steps: Take the preparation of 10 kg of Composition A as an example.

[0037] Step one (signal molecule loading): weigh 5.0 kg of mesoporous biochar and 2.5 kg of zeolite powder and place them in a horizontal ribbon mixer for 10 minutes. Dissolve 500 mg of 3-oxo-C6-HSL signal molecule in 2 L of 95% (v / v) ethanol. Start the mixer and evenly spray the signal molecule solution into the powder within 30 minutes through a spray device. Continue stirring for 60 minutes until the ethanol is completely volatilized and the powder is dry.

[0038] Step two (dry powder mixing): add 1.5 kg of potassium humate powder and 0.5 kg of chitosan powder to the above mixture loaded with signal molecules and continue dry mixing for 20 minutes to ensure uniform mixing of all components.

[0039] Step three (preparation and granulation): transfer the above uniformly mixed dry powder to a trough-type mixing kneader. Take another container and mix 50 L of water with 500 g of glacial acetic acid to prepare a 1% acetic acid solution by mass fraction as a wetting binder. Start the kneader and slowly spray the acetic acid solution into the dry powder until the material reaches a suitable plastic state (can be formed into a ball by hand and scattered by a light touch). The prepared wet material is sent to a pair of roller extrusion granulators and extruded through a 3 mm diameter die.

[0040] Step four (drying): evenly spread the prepared cylindrical wet granules on a baking tray and send them to a 40°C forced air oven for continuous drying for 24 hours until the final product has a moisture content of less than 8%. After drying, cool to room temperature and seal for packaging to obtain the finished product of Composition A.

[0041] Example 2: Preparation of liquid microbial inoculant (Composition B, C, D) This example specifically illustrates the preparation process of Composition B, C, D.

[0042] Strain list: Composition B: Aspergillus niger CGMCC No. 3.1234, Bacillus subtilis CGMCC No. 1.5678, Bacillus amyloliquefaciens CGMCC No. 1.9012.

[0043] Composition C: Bacillus stearothermophilus ATCC 7953, Nitrosomonas europa sp. (laboratory constructed strain, responsive to 3-oxo-C6-HSL), Nitrobacter sp. (laboratory constructed strain, responsive to 3-oxo-C6-HSL).

[0044] Composition D: Bacillus megaterium CGMCC No. 1.3456, Rhodopseudomonas palustris (photosynthetic bacteria) CGMCC No. 1.7890, engineered Saccharomyces cerevisiae carrying metallothionein gene (laboratory constructed strain).

[0045] Culture and compounding: Preparation of Composition B: The three strains above were inoculated into LB liquid medium respectively, and cultured at 35°C, 150 rpm for 48 hours. The viable cell count of each was determined by plate counting method, and then the corresponding volume of bacterial liquid was taken for mixing, so that the effective viable cell count (CFU) ratio of the three strains in the final bacterial agent was 1:1:1, and the total viable cell count was not less than 1×10 9 CFU / mL.

[0046] Preparation of Composition C: Bacillus stearothermophilus was inoculated into LB medium and cultured at 55°C, 150 rpm for 24 hours. The two signal-responsive nitration functional strains were inoculated into their specific inorganic salt liquid medium respectively, and cultured at 30°C, 120 rpm for 72 hours. After the viable cell count was determined, they were mixed in a CFU ratio of Bacillus stearothermophilus: Nitrosomonas: Nitrobacter = 3:1:1 to prepare Composition C, and the total viable cell count was not less than 1×10 9 CFU / mL.

[0047] Preparation of Composition D: Bacillus megaterium and engineered yeast were inoculated into LB and YPD medium respectively, and cultured at 30°C, 150 rpm for 48 hours. The photosynthetic bacteria were inoculated into its special medium and cultured under anaerobic conditions with 3000 lux light for 72 hours. After the viable cell count was determined, they were mixed in a CFU ratio of Bacillus megaterium: photosynthetic bacteria: engineered yeast = 1:1:1 to prepare Composition D, and the total viable cell count was not less than 1×10 9 CFU / mL.

[0048] All prepared liquid bacterial agents were stored at 4°C and used within 48 hours.

[0049] Example 3: Complete implementation process of the method of the application This example demonstrates the complete process of organic fertilizer production using the composition products prepared in Example 1 and Example 2.

[0050] Raw material pretreatment: Take the kitchen waste from the catering industry, after solid-liquid separation, mix with corn straw crushed to 3 cm in length at a ratio of 3:1 by dry weight. Detect and adjust the initial C / N ratio of the mixture to 30:1 and the moisture content to 60%. Put the treated material totaling 1000 kg into a fermentation tank equipped with forced ventilation and turning device.

[0051] First stage (Day 1-3): evenly sprinkle 50 kg (5% of the total wet weight) of composition A granules prepared in Example 1 into the material and turn it over. Then, evenly spray 2 L (0.2% of the total wet weight) of composition B inoculant prepared in Example 2 on the material after dilution, and turn it over again. This stage turns the pile 1 time a day, and maintains an intermittent ventilation of 0.1 m 3 / (min·m 3 ).

[0052] Second stage (Day 4-9): on the morning of the 4th day, evenly spray 2 L of composition C inoculant into the pile during the turning process after dilution. Increase the ventilation to 0.15 m 3 / (min·m 3 ), so that the pile temperature rises to 60°C within 48 hours, and use ventilation and turning (1 time every 2 days) to maintain the temperature within the range of 60°C ± 2°C for 5 days.

[0053] Third stage (Day 10-15): it is monitored that the pile temperature naturally falls below 45°C on the 10th day. On the same day, evenly spray 2 L of composition D inoculant into the pile during the turning process after dilution. Reduce the ventilation to 0.05 m 3 / (min·m 3 ), turn the pile 1 time every 3 days until the fermentation is complete.

[0054] End of fermentation: by the 15th day, the fermentation is complete. The final product is loose black-brown with a soil fragrance, no foul odor, and no original waste form has been observed. Take samples for testing.

[0055] Comparative Example 1: Traditional high-temperature aerobic fermentation Compared with Example 3, the difference is that during the entire fermentation process, no composition A prepared in Example 1 is added, and no composition B, composition C and composition D prepared in Example 2 are added, only natural fermentation is carried out by controlling ventilation and turning. The rest of the conditions such as raw material pretreatment, fermentation equipment, overall temperature control and turning strategy are consistent with the description of Example 3.

[0056] Comparative Example 2: Fermentation with one-time addition of general carrier and mixed bacterial agent The difference compared with Example 3 is that: On the first day of fermentation, the 50 kg of carrier added was ordinary mesoporous biochar without signal molecules and other functional components.

[0057] The liquid bacterial agents of Composition B, Composition C and Composition D prepared in Example 2 were physically mixed in advance and added into the fermentation material all at once on the first day of fermentation along with ordinary biochar. The rest of the conditions such as raw material pretreatment, fermentation equipment and process parameter control were consistent with the description of Example 3.

[0058] Comparative Example 3: Fermentation with sequential batch addition but using non-functional carrier The only difference compared with Example 3 is that the 50 kg of carrier added in the first stage was ordinary mesoporous biochar without N-acyl homoserine lactone signal molecules, zeolite, potassium humate and chitosan, i.e. an equal amount of ordinary mesoporous biochar was used to replace Composition A prepared in Example 1. All the rest of the conditions, including the types, addition amounts, addition time sequences of Composition B, C and D and the process parameter control of each stage, were exactly the same as described in Example 3.

[0059] Test Example 1: Detection of physicochemical properties and fertilizer efficiency indicators of final product In order to verify the technical effects of the technical solutions of the present application, samples of the final products after fermentation of Example 3 and Comparative Examples 1, 2 and 3 were taken and detected for key physicochemical properties and fertilizer efficiency related indicators.

[0060] Experimental method Sample collection and preparation: At the end of fermentation, samples were collected from the fermentation tanks of Example 3 and each comparative example using the multi-point sampling method (5 points from each of the upper, middle and lower layers), and the samples from the same tank were thoroughly mixed to form representative samples. The samples were naturally air-dried, then dried to constant weight in an oven at 65°C, pulverized with a pulverizer and sieved through a 0.25 mm aperture sieve before being packed into sealed bags for use.

[0061] Indicator detection: Total nitrogen (TN) content: determined by Kjeldahl method.

[0062] Ammonium nitrogen (NH4 + -N) content: determined by 2 mol / L KCl solution extraction and indigo blue colorimetry.

[0063] Nitrate nitrogen (NO3 - -N) content: determined by 2 mol / L KCl solution extraction and ultraviolet spectrophotometry.

[0064] Organic matter (OM) content: Determined by potassium dichromate volumetric method-external heating method.

[0065] Seed germination index (GI): The dried sample was mixed with deionized water at a ratio of 1:10 (w / v), shaken for 1 hour, and then filtered to obtain the extract. The extract was diluted and used for seed germination experiments. Twenty full small cabbage seeds were selected and placed in a culture dish lined with filter paper, and 5 mL of the test extract was added. The same amount of deionized water was added as a control. The culture dishes were placed in a 25°C constant temperature incubator for 72 hours, and then the seed germination rate and root length were calculated.

[0066] Germination index (GI) (%) = (treatment group seed germination rate x treatment group average root length) / (control group seed germination rate x control group average root length) x 100%.

[0067] The experimental results of the end products of Example 3 and each comparative example were detected by the above indicators, and the results are recorded in Table 1 below.

[0068] Table 1: Comparison of physical properties and fertilizer efficiency indicators of the fermentation end products of Example 3 and each comparative example As can be seen from the data in Table 1, the organic fertilizer product prepared by the method of Example 3 of the present application has different technical effects in terms of total nitrogen content, nitrate nitrogen content, and seed germination index compared to Comparative Examples 1, 2, and 3. Specifically, the product of Example 3 has a higher total nitrogen content and seed germination index than each of the comparative examples, and its nitrate nitrogen content is significantly higher than that of all the comparative examples, while the ammonium nitrogen content is at a relatively low level.

[0069] The technical effects presented by the technical solution are directly related to the internal material and information synergistic regulation mechanism. In Example 3, the ammonium nitrogen produced in the high temperature stage is subjected to preset regulation in its subsequent conversion path. This regulation is achieved by the slow-release N-acyl homoserine lactone signal molecule in Composition A. The signal molecule induces the metabolic activity of the signal-responsive nitrification functional strain in Composition C added later in a specific time window, thereby efficiently and in situ converting the volatile loss-prone ammonium nitrogen into stable nitrate nitrogen, which is then trapped by the porous carrier in Composition A. Although Comparative Example 3 also uses sequential batch addition, the lack of signal molecule induction results in insufficient activity of the nitrification functional strain, leading to low conversion efficiency of nitrate nitrogen, residual or volatile loss of nitrogen in the form of ammonium nitrogen, and lower total nitrogen retention rate than Example 3.

[0070] Compared with the traditional fermentation (Comparative Example 1) and the non-sequential fermentation of mixing all components at one time (Comparative Example 2), the present application constructs a sequential microbial ecological succession process by sequentially adding functional microbial agents (Compositions B, C, and D). Composition B establishes a dominant ecological niche for the subsequent microbial population, Composition C performs controlled nitrogen fixation while performing high-temperature decomposition, and Composition D completes the final composting and efficiency enhancement under suitable temperature and substrate conditions. This interlocking programmed synergy ensures that each functional microorganism performs its specific function at the most suitable time and space, ultimately resulting in a comprehensive result of the product in terms of nitrogen form, content, and biological safety (characterized by GI).

[0071] Test Example 2: Monitoring of key gas emissions during fermentation process In order to further verify the technical effect of the technical solution of the present application in terms of nitrogen retention from the process control point of view, the ammonia (NH3) emission during the fermentation process of Example 3 and Comparative Examples 1, 2, and 3 was monitored.

[0072] Experimental method Gas collection and monitoring: An inverted static gas collection hood was installed at the top center of each fermentation tank, and the gas outlet of the collection hood was connected to an online ammonia analyzer (model: Gas-ProNH3-1000) through a pipeline. A micro-pump was used to draw the gas emitted from the surface layer of the fermentation pile into the analyzer at a constant flow rate of 0.5 L / min. From the 4th day to the 12th day of fermentation, the ammonia concentration was measured at 10:00 am every day, each measurement lasted for 10 minutes, and the peak concentration during this period was recorded.

[0073] Cumulative emission estimation: Based on the daily measured concentration, gas flow rate, and set daily ventilation time, the daily ammonia emission was estimated and accumulated to obtain the cumulative ammonia emission during the high-temperature stage (Day 4-12).

[0074] The experimental results of monitoring the ammonia emission during the fermentation process of Example 3 and each comparative example are recorded in Table 2.

[0075] Table 2: Comparison of ammonia emissions during the high-temperature stage of fermentation of Example 3 and each comparative example As can be seen from the data in Table 2, the peak concentration and cumulative emission of ammonia during the high-temperature stage of fermentation of Example 3 are significantly lower than those of Comparative Examples 1, 2, and 3. This result shows that the technical solution of the present application can effectively inhibit the ammonia volatilization during the fermentation process, thereby fixing more nitrogen in the fermentation product.

[0076] The technical effect is achieved by the in-situ biological nitrogen fixation pathway regulated by the signal molecules constructed in the present solution. During the high-temperature stage of Example 3, a large amount of ammonia is produced by the mineralization of organic nitrogen. At the same time, the signal molecules loaded in Composition A are continuously released, and when their concentration reaches a certain threshold, the metabolic activity of the signal-responsive nitrifying functional strain in Composition C is induced, rapidly converting the ammonia / ammonium ions in the micro-domain of the pile into non-volatile nitrate nitrogen. This process converts nitrogen from a volatile form to a stable form, directly reducing the emission flux of gaseous ammonia. Although Comparative Example 3 also performs sequential batch addition, because the carrier does not contain pre-set signal molecules, the metabolic activity of the nitrifying functional strain cannot be precisely matched with the ammonia generation rate, resulting in a large amount of ammonia being lost by volatilization before being converted.

[0077] Compared with Comparative Example 1 (without exogenous microbial agents) and Comparative Example 2 (one-time mixed addition of microbial agents), the present solution also has the advantage of its programmed microbial community construction. In Comparative Example 2, the non-thermophilic nitrifying bacteria are introduced prematurely along with other bacteria, and their activity is inhibited in the high-temperature environment, making it impossible to effectively perform the nitrogen fixation function. Example 3, by adding functionally independent compositions at different stages, ensures that the thermophilic heat-producing function and the non-thermophilic nitrifying nitrogen fixation function work in their respective optimal environmental windows, avoiding functional antagonism and environmental intolerance problems among microorganisms, and ultimately forming an efficient nitrogen fixation system, the effectiveness of which is demonstrated by the significant reduction in ammonia gas emissions.

[0078] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A microbial composition product for organic waste fermentation, characterized in that: The product comprises at least the following four independent compositions: Composition A: A signal-slow-release functional carrier, which comprises, by dry weight: Mesoporous biochar: 40%-60%; Zeolite powder: 20%-30%; Potassium humate: 5%-15%; Chitosan: 1%-5%; and a pre-defined microbial quorum sensing signaling molecule; Composition B: a composite bacterial agent for the hydrolysis start-up period; Composition C: a signal-responsive thermophilic composite bacterial agent; Composition D: A composite bacterial agent for the decomposition and enhancement period.

2. A microbial composition product for organic waste fermentation according to claim 1, characterized in that: The preset microbial quorum sensing signal molecule in the composition A is an N-acyl homoserine lactone signal molecule.

3. The microbial composition product for organic waste fermentation according to claim 1, characterized in that: The microorganisms in the composition C include at least one signal-responsive nitrification functional strain, and the activation of the nitrification metabolic pathway of the strain is specifically induced by the microbial quorum sensing signal molecules preset in the composition A.

4. The microbial composition product for organic waste fermentation according to claim 1, characterized in that: The microorganisms in the composition B are capable of metabolizing and producing bacitracin that has no inhibitory effect on the functional strains in the composition C and the composition D; The microorganisms in the composition C are capable of metabolizing and producing specific growth factors that promote the growth of the functional strains in the composition D.

5. A method for rapidly producing organic fertilizer from organic waste using an ecological method based on the product of claim 1, characterized in that: The following steps are involved: a) mixing organic waste with the composition A according to any one of claims 1 to 4 to form an initial fermentation material; b) adding the composition B, composition C, and composition D according to any one of claims 1 to 4 to the fermentation initial material or its subsequent fermentation product in a sequential batch manner according to a preset time sequence, guiding the fermentation process through three different stages: hydrolysis initiation, high temperature thermophilicity, and composting synergistic enhancement.

6. The method for rapidly producing organic fertilizer from ecological organic waste according to claim 5, wherein: The specific operations of step b) are: During the start-up phase of the fermentation process, composition B is added to degrade macromolecular organic matter and establish a niche for dominant microorganisms; When the fermentation process enters the high-temperature stage, composition C is added to perform high-temperature harmless treatment, and the nitrifying functional strains in composition C receive the signal molecules released from composition A and are activated to perform in-situ biological nitrogen fixation within the fermentation system; During the cooling and composting stage of the fermentation process, the composition D is added to complete the composting of the materials and enhance their functions.

7. The method for rapidly producing organic fertilizer from ecological organic waste according to claim 6, wherein: During the startup phase, composition B is added to inhibit spoilage bacteria in the fermentation material by utilizing the bacitracin produced by its metabolism.

8. The method for rapidly producing organic fertilizer from ecological organic waste according to claim 6, wherein: In the high temperature stage, the thermophilic bacteria in composition C undergoes thermogenic decomposition, and at the same time, the signal-responsive nitrification functional bacteria contained therein convert ammonia or ammonium ions produced by mineralization in the material into nitrate nitrogen.

9. The method for rapidly producing organic fertilizer from ecological organic waste according to claim 6, wherein: During the decomposition and synergistic stage, the metabolites of composition C provide growth factors for the functional strains in composition D, promoting their degradation of antibiotics or passivation of heavy metals.

10. The method for rapidly producing organic fertilizer from organic waste using an ecological method according to claim 6, wherein: The temperature control characteristics of the three stages are: The temperature of the hydrolysis startup stage is controlled at 30°C-45°C, the temperature of the high-temperature thermophilic stage is controlled at 55°C-65°C, and the composting and synergistic stage is a process of natural cooling from below 45°C.

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