Fermentation method for preparing fertilizer by utilizing wine-making pot-bottom water

Abstract

The fermentation method comprises the following steps: (1) raw material pretreatment: carrying out solid-liquid separation on the wine-making pot-bottom water, adjusting the pH value, and carrying out heavy metal adsorption; (2) directional fermentation of a complex microbial inoculant: primary fermentation: inoculating the complex microbial inoculant, and carrying out aerobic fermentation; secondary fermentation: after the aerobic fermentation is finished, carrying out micro-aerobic fermentation; third-stage fermentation: after the micro-aerobic fermentation is finished, carrying out anaerobic fermentation; (3) nutrient enhancement and stabilization: after anaerobic fermentation is finished, obtaining fermentation liquor, and adding urea and the like to enable nitrogen, phosphorus and potassium to reach a set proportion; adding EDTA chelated trace elements, and uniformly mixing; and (4) preparing a finished product: carrying out solid-liquid separation on the solution obtained in the step (3) to remove thallus residues, sterilizing, and adding xanthan gum to obtain the liquid fertilizer. The full-component utilization rate of the wine-making pot-bottom water reaches 80%, the conversion rate of organic acid is 85%, and the utilization rate of residual sugar is 90%.

Description

Technical Field

[0001] The present invention relates to the field of agricultural fertilizers, and particularly to a fermentation method for preparing fertilizers by using the bottom pan water of brewing. Background Art

[0002] Disclosing the information of this background art section is only intended to increase some understanding of the overall background of the present invention, and is not necessarily regarded as an admission or an implication in any form that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] The bottom pan water (distillers' grains water) of liquor brewing industry is the main by-product of liquor brewing industry. At present, its treatment and resource utilization technologies mainly include: direct discharge or simple treatment: some enterprises directly discharge the bottom pan water into the water body or discharge it after simple precipitation, resulting in environmental pollution problems such as eutrophication of water bodies and exceeding the standards of COD / BOD. Traditional composting: mixing the bottom pan water with straws, etc. for natural composting, but the fermentation period is long (3 - 6 months), the nutrient loss is large (nitrogen volatilization rate > 30%), and the inactivation of pathogenic bacteria is not thorough. Feed utilization: drying to make feed, but the residual alcohol (0.5% - 1.2%) and tannic acid in the bottom pan water are harmful to the digestive system of animals, and the processing energy consumption is high. Anaerobic fermentation to produce biogas: using the bottom pan water to produce biogas, but the subsequent treatment of biogas slurry is difficult (heavy metal accumulation), and the organic matter resources are not fully utilized with high value.

[0004] The above technologies have the following defects: environmental pollution risk: direct discharge or inefficient treatment leads to water pollution, violating environmental protection regulations. Resource waste: traditional composting and feed utilization processes fail to effectively extract the organic matter, amino acids and trace elements (such as potassium and phosphorus) in the bottom pan water. Low process efficiency: the natural fermentation period is long, and the microbial activity is insufficient (the number of effective bacteria < 1×10 4 CFU / mL), resulting in slow release of fertilizer efficiency. Safety problems: residual alcohol, tannic acid and undegraded macromolecular organic matters (such as lignin) inhibit the root development of crops, and even cause soil acidification (pH < 5.5).

[0005] The reasons for the above defects not being solved are as follows: technical complexity: the composition of the bottom pan water is complex (containing cellulose, hemicellulose, lignin and other difficult-to-degrade substances), and multi-strain co-fermentation is required, but the compatibility of existing bacterial agents is poor.

[0006] Economic bottleneck: the investment in high-efficiency fermentation equipment (such as continuous reactors) is high, and small and medium-sized enterprises are difficult to bear; the traditional process has low cost but poor benefits, lacking market motivation. Industry cognitive limitation: the agricultural field pays insufficient attention to the high-value utilization of brewing waste, and the policy support and scientific research investment are limited. Summary of the Invention

[0007] In view of the deficiencies of the prior art, the present invention realizes the whole - process conversion of carbon source (residual sugar) → energy (ethanol) → nutrients (amino acids, humic acid) in the bottom - pot water through a composite microbial agent (acid - tolerant yeast + phosphate - solubilizing bacteria), and the resource utilization rate is increased to 90%. The present invention can reduce the wastewater treatment cost by more than 40% and replace 15% of chemical fertilizers at the same time, promoting the liquor industry to shift from "end - of - pipe treatment" to cross - industrial chain integration of "production - environmental protection - agriculture".

[0008] The technical solution adopted in the present invention is as follows: In the first aspect of the present invention, a fermentation method for preparing fertilizer by using bottom - pot water from liquor brewing is provided. The method includes the following steps: (1) Raw material pretreatment: The bottom - pot water from liquor brewing is subjected to solid - liquid separation to remove solid residues, the pH is adjusted to 5.5 - 6.0, and then heavy - metal adsorption is carried out; (2) Directed fermentation of the composite microbial agent: Primary fermentation: Inoculate the composite microbial agent and carry out aerobic fermentation with the dissolved oxygen content DO≥4 mg / L, and ferment at 38 - 40 °C for 10 - 14 h; the composite microbial agent is composed of Saccharomyces boulardii ( Saccharomyces cerevisiae var. boulardii ) and Pseudomonas fluorescens ( Pseudomonas fluorescens ); Secondary fermentation: After the aerobic fermentation is completed, carry out micro - aerobic fermentation with the dissolved oxygen content DO of 0.5 - 1 mg / L, and ferment at 33 - 35 °C for 60 - 72 h. Add phosphate rock powder before the micro - aerobic fermentation; Tertiary fermentation: After the micro - aerobic fermentation is completed, carry out anaerobic fermentation and ferment at 28 - 30 °C for 90 - 96 h; (3) Nutrient strengthening and stabilization: After the anaerobic fermentation is completed, obtain the fermentation broth, add urea, phosphate rock powder, and potassium sulfate to make the nitrogen, phosphorus, and potassium reach the set ratio; then add EDTA - chelated trace elements and mix evenly; (4) Finished - product preparation: Solid - liquid separate the solution obtained in step (3) to remove the microbial residues, sterilize, and add xanthan gum to obtain the liquid fertilizer.

[0009] In one or some embodiments of the present invention, in step (1), the initial pH of the bottom - pot water from liquor brewing is 4.0 - 4.5, and the ethanol content is 2 - 3 v / v%. Neutralize the acidic bottom - pot water to 5.5 - 6.0 to avoid inhibiting the activity of subsequent fermenting bacteria.

[0010] In one or some embodiments of the present invention, in step (1), the heavy - metal adsorption is carried out by using modified bentonite adsorption and chelating bacteria ( Bacillus subtilis ) fixation. The lead content in the finally obtained finished product is ≤3 mg / kg, and the cadmium content is ≤0.5 mg / kg, which is better than the limit value of the "Organic Fertilizer Standard" (NY / T 525 - 2021), achieving a breakthrough in the industry in terms of heavy - metal safety control.

[0011] In one or some embodiments of the present invention, in the primary fermentation of step (2), the ratio of the viable bacteria count of Saccharomyces boulardii to Pseudomonas fluorescens is 6:(3 - 5); preferably 6:4, and it is added in the form of a bacterial solution with a viable bacteria content of 1×10 8 CFU / mL. The inoculation amount of the composite bacterial agent is 8% - 10% of the volume of the bottom pan water, preferably 9%.

[0012] In one or some embodiments of the present invention, in the primary fermentation of step (2), it is fermented at 40°C for 12 h.

[0013] In one or some embodiments of the present invention, in step (2), during the primary fermentation, the microorganisms degrade the residual sugar, and after the aerobic fermentation ends, the ethanol concentration is reduced to 0.5 v / v% or less.

[0014] In one or some embodiments of the present invention, in the secondary fermentation of step (2), it is fermented at 35°C for 72 h.

[0015] In one or some embodiments of the present invention, in the secondary fermentation of step (2), phosphate rock powder is added to promote Pseudomonas fluorescens to release soluble phosphorus, and the dissolution rate of the phosphate rock powder is increased to 80%; the addition amount is 4 - 6 kg of phosphate rock powder per ton of bottom pan water, preferably 5 kg, and the dissolution rate of the phosphate rock powder is increased to more than 80% by means of stirring dissolution + acidolysis assistance.

[0016] In one or some embodiments of the present invention, in the tertiary fermentation of step (2), it is fermented at 30°C for 96 h.

[0017] In one or some embodiments of the present invention, in step (2), after the anaerobic fermentation ends, the fermentation broth contains humic acid (≥15%) and amino acids (≥8 g / L).

[0018] In one or some embodiments of the present invention, in step (3), urea, phosphate rock powder, and potassium sulfate are added to make the N - P - K weight ratio reach 1:0.5:1.2.

[0019] In one or some embodiments of the present invention, in step (3), the EDTA - chelated trace elements are EDTA - chelated zinc and EDTA - chelated iron, and the ratio of EDTA - chelated zinc to EDTA - chelated iron is not limited. The addition amount of the EDTA - chelated trace elements is 0.1 w / w%, which means that the weight of the added EDTA - chelated trace elements is 0.1% of the weight of the solution after adding urea, phosphate rock powder, and potassium sulfate.

[0020] In one or some embodiments of the present invention, in step (4), solid-liquid separation is carried out by using a centrifuge to remove bacterial residues (solid content ≤ 0.5%) at a rotational speed of 3,000 rpm.

[0021] In one or some embodiments of the present invention, in step (4), pasteurization (65 °C / 30 min) is used to inactivate microorganisms, and the total number of colonies in the finished product is ≥ 1×10 3 CFU / mL.

[0022] In one or some embodiments of the present invention, in step (4), the addition amount of xanthan gum is 0.1 w / w%, which means that the weight of the added xanthan gum is 0.1% of the weight of the sterilized solution.

[0023] The present invention uses three-stage fermentation for brewing bottom pan water. First-stage fermentation: aerobic degradation of residual sugar, and the ethanol conversion rate ≥ 95%; second-stage fermentation: micro-aerobic release of soluble phosphorus, and the dissolution rate of phosphate rock powder is increased to 80%; third-stage fermentation: anaerobic synthesis of humic acid, and the carbon source utilization rate reaches 92%.

[0024] The directional screening and adaptability optimization of the composite microbial agent of the present invention: using a composite strain of acid-resistant yeast ( Saccharomyces cerevisiae var. boulardii ) and phosphate-solubilizing bacteria ( Pseudomonas fluorescens ) (the ratio of viable bacteria is 6:4), breaking through the activity limitation of traditional strains in the acidic (pH 4 - 5) and ethanol-containing (1 - 3%) environment of bottom pan water; nutrient dynamic regulation: by supplementing urea, phosphate rock powder, potassium sulfate (ratio 1:0.5:1.2), combined with fermentation and mineralization, to solve the problem of unbalanced nutrient of traditional bottom pan water fertilizers.

[0025] Through the above method, the overall component utilization rate of brewing bottom pan water reaches 80% (traditional technology ≤ 50%), among which the organic acid conversion rate is 85% and the residual sugar utilization rate is 90%.

[0026] In the second aspect of the present invention, a liquid fertilizer prepared by using the above method is provided; the content of humic acid in the liquid fertilizer is ≥ 5 w / w% and the amino acid is ≥ 8 g / L.

[0027] Specifically, the liquid fertilizer has the technical indicators shown in Table 1: Table 1 Liquid Fertilizer Index

[0028] In the third aspect of the present invention, a system for preparing fertilizer by using brewing bottom pan water is provided. The system includes a pretreatment unit, a fermentation unit, a nutrient regulation unit, and a post-treatment unit; The pretreatment unit includes a pH adjustment tank, a raw material tank, a solid-liquid separation sieve, and a heavy metal adsorption column connected in sequence; The fermentation unit includes a compound bacterial agent activation tank, a primary fermentation tank connected to a heavy metal adsorption column, a secondary fermentation tank, and a tertiary fermentation tank that are connected in sequence, and a dissolved oxygen regulation system connected to the three fermentation tanks. The dissolved oxygen regulation system includes an air compressor and a dissolved oxygen / temperature adjustment device; The nutrient regulation unit includes a nitrogen, phosphorus, and potassium supplement tank connected to the primary fermentation tank and a chelating agent sprayer connected to the tertiary fermentation tank; The post-treatment unit includes a centrifuge connected to the tertiary fermentation tank and a pasteurizer, a concentration device, a storage device, and a finished product tank that are connected to the centrifuge in sequence.

[0029] In one or some embodiments of the present invention, the centrifuge removes bacterial residues (solid content ≤ 0.5%) at a rotational speed of 3,000 rpm.

[0030] In one or some embodiments of the present invention, the pasteurizer (65°C / 30 min) inactivates microorganisms, and the total number of viable colonies in the finished product ≥ 1×10 3 CFU / mL.

[0031] Compared with the related technologies known to the inventors of the present invention, one of the technical solutions of the present invention has the following beneficial effects: (1) Turning waste into treasure: converting all acids, alcohols, sugars, etc. in the bottom pan water into fertilizer components (humic acid, amino acids, etc.), with a utilization rate exceeding 80%.

[0032] (2) Low-cost treatment: using acid- and ethanol-resistant composite strains, eliminating the distillation step, and reducing the treatment energy consumption by 75%.

[0033] (3) Safe and efficient: fixing heavy metals through strains to ensure that the fertilizer meets national standards; adding nitrogen, phosphorus, and potassium to regulate nutrients and reduce soil acidification. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The specification drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0035] Figure 1 It is a flowchart of the fermentation process for preparing fertilizer using the bottom pan water of brewing.

[0036] Among them, 1. pH adjustment tank, 2. raw material tank, 3. solid-liquid separation sieve, 4. heavy metal adsorption column, 5. complex microbial agent activation tank, 6-1. primary fermentation tank, 6-2. secondary fermentation tank, 6-3. tertiary fermentation tank, 7-1. air compressor, 7-2. dissolved oxygen / temperature adjustment equipment, 8. nitrogen, phosphorus and potassium supplement tank, 9. chelating agent sprayer, 10. centrifuge, 11. pasteurizer, 12. concentration equipment, 13. storage equipment, 14. finished product tank. Detailed implementation mode

[0037] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0038] It should be noted that the terms used herein are only for describing specific implementation modes and are not intended to limit the exemplary implementation modes according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, and / or combinations thereof.

[0039] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in combination with specific embodiments.

[0040] Example 1: A fermentation method for preparing fertilizer using the bottom pot water of brewing, the method comprising the following steps: (1) Raw material pretreatment: The bottom pot water of brewing (from the bottom pot water of Luzhou-flavor liquor produced by Yibin Xufu Winery, initial pH 4.0 - 4.5, ethanol content 1.8 v / v%, total sugar content 0.5 w / v%) is subjected to solid-liquid separation to remove solid residues. The solid-liquid separation is carried out using a solid-liquid separation sieve, which uses a stainless steel sieve mesh with a pore size of 0.5 mm to remove the distiller's grains residues in the bottom pot water (filtration efficiency ≥ 95%); quicklime is added to the pH adjustment tank to neutralize the acidic bottom pot water to a pH of 5.5 - 6.0, and then a heavy metal adsorption column (filled with modified bentonite, loaded with chelating bacterium Bacillus subtilis) is used for heavy metal adsorption, adsorbing ionic heavy metals such as lead and cadmium to ≤ 5 mg / kg, meeting the NY / T 525-2021 standard, and reducing the COD from 50,000 mg / L to 12,000 mg / L; (2) Directed fermentation of complex microbial agent: This embodiment uses a compound bacterial agent liquid, which is obtained by activating in a bacterial agent activation tank. In the bacterial agent activation tank, Saccharomyces boulardii and Pseudomonas fluorescens are added and mixed at a ratio of viable bacteria numbers of 6:4, activated at 35 °C for 12 hours, and the bacterial liquid concentration reaches 1×10 8 CFU / mL.

[0041] Primary fermentation: Inoculate 9% of the compound bacterial agent liquid into the raw materials pretreated in step (1), and perform aerobic fermentation (DO is 5.2 mg / L, 40 °C / 48 h) to degrade residual sugar, and reduce the ethanol concentration to less than 0.5%; Secondary fermentation: Micro-aerobic fermentation (DO 0.8 mg / L, 35 °C / 72 h), add phosphate rock powder to promote the release of soluble phosphorus by phosphate-solubilizing bacteria, and increase the dissolution rate of phosphate rock powder to 80%; the amount of phosphate rock powder added per ton of bottom pan water is 5 kg; Tertiary fermentation: Anaerobic fermentation (30 °C / 96 h), detect after the anaerobic fermentation ends, generate humic acid at 18 w / w% and amino acids at 10 g / L, and the carbon source utilization rate reaches 92%.

[0042] (3) Nutrient enhancement and stabilization: Add urea (1.5 w / w%), phosphate rock powder (0.8 w / w%), and potassium sulfate (1.2 w / w%) to the supplement tank to make the N-P-K ratio reach 1:0.5:1.2; add 0.1 w / w% EDTA chelated trace elements (iron, zinc) to the sprayer to prevent precipitation and improve nutrient stability.

[0043] This step can dynamically regulate the N-P-K ratio (real-time feedback from sensors) and add chelating agents to prevent nutrient precipitation.

[0044] (4) Finished product preparation: The centrifuge removes bacterial residues at a speed of 3,000 rpm (the solid content ≤ 0.5%); the total number of colonies of the finished product ≥ 1×10 3 CFU / mL, and then add 0.1 w / w% xanthan gum for anti-precipitation treatment, and fill the finished liquid fertilizer. The fertilizer indexes are shown in Table 2.

[0045] Example 2: A fermentation method for preparing fertilizer using brewing bottom pan water, the method comprising the following steps: (1)Raw material pretreatment: The distillery bottom water (from the Luzhou-flavor liquor distillery bottom water produced by Yibin Xufu Liquor Industry, with an initial pH of 4.0 - 4.5, an ethanol content of 2 v / v%, and a total sugar content of 0.5 w / v%) is subjected to solid-liquid separation to remove solid residues. The solid-liquid separation is carried out using a solid-liquid separation sieve with a 0.5 mm aperture stainless steel screen to remove the distiller's grains residues in the bottom water (filtration efficiency ≥ 95%); quicklime is added to the pH adjustment tank to neutralize the acidic bottom water to a pH of 5.5 - 6.0, and then a heavy metal adsorption column (filled with modified bentonite and loaded with chelating bacteria Bacillus subtilis) is used for heavy metal adsorption, adsorbing ionic heavy metals such as lead and cadmium to ≤ 5 mg / kg, meeting the NY / T 525 - 2021 standard, and reducing the COD from 50,000 mg / L to 12,000 mg / L; (2)Directed fermentation with compound microbial agents: In this example, a compound microbial agent liquid is used, which is obtained by activating in a microbial agent activation tank. In the microbial agent activation tank, Saccharomyces boulardii and Pseudomonas fluorescens are added and mixed in a ratio of 6:4 by viable cell count, and activated at 35 °C for 12 hours, and the bacterial liquid concentration reaches 1×10 8 CFU / mL.

[0046] Primary fermentation: Inoculate 9% of the compound microbial agent liquid into the raw materials pretreated in step (1) and carry out aerobic fermentation (DO is 5.5 mg / L, 40 °C / 48 h) to degrade the residual sugar and reduce the ethanol concentration to below 0.5%; Secondary fermentation: Micro-aerobic fermentation (DO 1 mg / L, 35 °C / 72 h), add phosphate rock powder to promote the release of soluble phosphorus by phosphorus-solubilizing bacteria, and the dissolution rate of phosphate rock powder is increased to 80%; the amount of phosphate rock powder added per ton of bottom water is 5 kg; Tertiary fermentation: Anaerobic fermentation (30 °C / 96 h). After the anaerobic fermentation is completed, it is detected that the humic acid generated is 20 w / w% and the amino acid is 12 g / L, and the carbon source utilization rate reaches 92%.

[0047] (3)Nutrient strengthening and stabilization: Urea (2.0 w / w%), phosphate rock powder (1.0 w / w%), and potassium sulfate (1.5 w / w%) are added to the supplement tank to make the N - P - K ratio reach 1:0.5:1.2; 0.1 w / w% EDTA chelated trace elements (iron, zinc) are added by the sprayer to prevent precipitation and improve the nutrient stability.

[0048] This step can dynamically adjust the N - P - K ratio (real-time feedback by sensors) and add chelating agents to prevent nutrient precipitation.

[0049] (4)Finished product preparation: The centrifuge removes the bacterial residues (solid content ≤ 0.5%) at a speed of 3,000 rpm; pasteurization (65°C / 30 min) inactivates microorganisms, and the total number of colonies in the finished product is ≥ 1×10 3 CFU / mL. Then, 0.1 w / w% xanthan gum is added for anti-precipitation treatment, and the finished liquid fertilizer is filled. The fertilizer indexes are shown in Table 2.

[0050] Example 3: A fermentation method for preparing fertilizer using distillery bottom water, which comprises the following steps: (1) Raw material pretreatment: The distillery bottom water (from the bottom water of Luzhou-flavor liquor produced by Xufu Distillery in Yibin City, with an initial pH of 4.0 - 4.5, an ethanol content of 2.1 v / v%, and a total sugar content of 0.5 w / v%) is subjected to solid-liquid separation to remove solid residues. The solid-liquid separation is carried out using a solid-liquid separation sieve with a 0.5 mm pore diameter stainless steel screen to remove the lees residues in the bottom water (filtration efficiency ≥ 95%); quicklime is added in the pH adjustment tank to neutralize the acidic bottom water to a pH of 5.5 - 6.0, and then a heavy metal adsorption column (filled with modified bentonite and loaded with chelating bacteria Bacillus subtilis) is used for heavy metal adsorption, adsorbing ionic heavy metals such as lead and cadmium to ≤ 5 mg / kg, meeting the NY / T 525-2021 standard, and reducing the COD from 50,000 mg / L to 12,000 mg / L; (2) Directed fermentation of compound microbial agents: In this example, a compound microbial agent liquid is used, which is obtained by activating in a microbial agent activation tank. In the microbial agent activation tank, Saccharomyces boulardii and Pseudomonas fluorescens are added and mixed in a ratio of 6:4 by viable count, and activated at 35°C for 12 hours, and the concentration of the bacterial liquid reaches 1×10 8 CFU / mL.

[0051] Primary fermentation: The raw materials pretreated in step (1) are inoculated with 8.5% compound microbial agent liquid for aerobic fermentation (DO is 6 mg / L, 40°C / 48 h) to degrade residual sugar, and the ethanol concentration is reduced to less than 0.5%; Secondary fermentation: Micro-aerobic fermentation (DO 0.6 mg / L, 35°C / 72 h), adding phosphate rock powder to promote the release of soluble phosphorus by phosphorus-solubilizing bacteria. The amount of phosphate rock powder added per ton of bottom water is 5 kg, and the dissolution rate of phosphate rock powder is increased to 80%; Tertiary fermentation: Anaerobic fermentation (30°C / 96 h). After the anaerobic fermentation is completed, it is detected that the humic acid generated is 16 w / w% and the amino acid is 11 g / L, and the carbon source utilization rate reaches 92%.

[0052] (3) Nutrient strengthening and stabilization: The supplementary tank is added with urea (1.8 w / w%), rock phosphate (0.9 w / w%), and potassium sulfate (1.5 w / w%) to make the N-P-K ratio reach 1:0.5:1.2; the sprayer is added with 0.1 w / w% EDTA chelated trace elements (iron, zinc) to prevent precipitation and improve the nutrient stability.

[0053] This step can dynamically regulate the N-P-K ratio (real-time feedback from sensors) and add chelating agents to prevent nutrient precipitation.

[0054] (4)Finished product preparation: The centrifuge removes the bacterial residues at a speed of 3,000 rpm (the solid content ≤ 0.5%); pasteurization (65°C / 30 min) inactivates microorganisms, and the total number of colonies in the finished product ≥ 1×10 3 CFU / mL, and then 0.1 w / w% xanthan gum is added for anti-precipitation treatment, and the finished liquid fertilizer is filled. The fertilizer indexes are shown in Table 2.

[0055] Example 4: A system for preparing fertilizer using the bottom water of wine brewing, which includes a pretreatment unit, a fermentation unit, a nutrient regulation unit, and a post-treatment unit; The pretreatment unit includes a pH adjustment tank 1, a raw material tank 2, a solid-liquid separation screen 3, and a heavy metal adsorption column 4 connected in sequence; The fermentation unit includes a complex bacterial agent activation tank 5, a primary fermentation tank 6-1, a secondary fermentation tank 6-2, and a tertiary fermentation tank 6-3 connected in sequence, which are connected to the heavy metal adsorption column. A dissolved oxygen regulation system is connected to the three fermentation tanks. The dissolved oxygen regulation system includes an air compressor 7-1 and a dissolved oxygen / temperature adjustment device 7-2; The nutrient regulation unit includes a nitrogen, phosphorus, and potassium supplementary tank 8 connected to the primary fermentation tank 6-1 and a chelating agent sprayer 9 connected to the tertiary fermentation tank 6-3; The post-treatment unit includes a centrifuge 10 connected to the tertiary fermentation tank 6-3 and a pasteurizer 11, a concentration device 12, a storage device 13, and a finished product tank 14 connected to the centrifuge in sequence.

[0056] Table 2 Liquid fertilizer indexes:

[0057] Comparative Example 1: The difference from Example 1 is that in step (1), quicklime is added to the pH adjustment tank to neutralize the acidic bottom water to pH 7. In step (2), Saccharomyces boulardii is replaced with Lactobacillus spp. Other steps and conditions are the same as those in Example 1.

[0058] It was found that the fermentation rate was slower after replacing yeast: Lactobacillus generally has a slower fermentation rate compared to Saccharomyces boulardii. Lactobacillus often produces lactic acid when decomposing organic matter, while Saccharomyces boulardii can convert sugars into alcohol more efficiently, so its fermentation process is faster and the yield is higher.

[0059] Too high acidity: Lactobacillus produces lactic acid during fermentation, significantly increasing the acidity of the environment. This increase in acidity affects the pH value of the bottom pan water, making the liquid fertilizer too acidic and reducing its suitability for plants. Saccharomyces boulardii can grow and ferment better in a low pH environment and can effectively regulate acidity to avoid excessive acidification.

[0060] Differences in by-products: The main by-product of Lactobacillus fermentation is lactic acid, which results in more organic acids in the fermentation broth. Although it has a certain promoting effect on some plants, for some crops, the high lactic acid content leads to unsatisfactory fertilizer application effects. Saccharomyces boulardii can not only produce alcohol but also decompose other organic substances to generate more beneficial metabolites such as amino acids and vitamins, promoting plant growth.

[0061] Differences in environmental adaptability: Lactobacillus has a poorer environmental adaptability compared to Saccharomyces boulardii. Especially under relatively large environmental changes, its fermentation efficiency will decline. Saccharomyces boulardii has strong tolerance to conditions such as changes in the acidity and alkalinity of the bottom pan water and temperature fluctuations. Therefore, under different experimental conditions, Saccharomyces boulardii can maintain a more stable fermentation effect.

[0062] Comparative example 2: The difference from Example 1 is that in step (2), Saccharomyces boulardii and Pseudomonas fluorescens are added to the bacterial agent activation tank in a ratio of 4:6 by viable cell count and activated at 35 °C for 12 hours, and the bacterial liquid concentration reaches 1×10 8 CFU / mL.

[0063] Other steps and conditions are the same as those in Example 1.

[0064] In actual fermentation, if the ratio of the two fermentation bacteria, Saccharomyces boulardii and Pseudomonas fluorescens, is inappropriate, the following adverse effects will occur: Low fermentation efficiency: Saccharomyces boulardii and Pseudomonas fluorescens play different roles in the fermentation process. Saccharomyces boulardii is mainly responsible for fermenting sugars to produce alcohol, while Pseudomonas fluorescens plays a key role in organic matter degradation and promoting plant growth. If the ratio of the two is inappropriate, the activity of one party will be inhibited, thus affecting the efficiency of the entire fermentation process. For example, if the ratio of Saccharomyces boulardii is too high, it will lead to excessive alcohol accumulation, inhibit the growth of Pseudomonas fluorescens, and reduce its ability to degrade harmful substances in the fermentation broth.

[0065] Accumulation of harmful substances: When Pseudomonas fluorescens decomposes organic matter, it can produce some beneficial metabolites, such as antibiotics and plant hormones, which help inhibit the growth of harmful microorganisms. If the proportion of Pseudomonas fluorescens is too low, it will lead to insufficient production of its metabolites, which will in turn affect the fertilizer's ability to kill bacteria, resist diseases and promote plant growth. If the proportion of Saccharomyces boulardii is too high, it will lead to excessive fermentation, and the alcohol and other by-products produced will have a negative impact on the environment and even be detrimental to plants.

[0066] Poor environmental adaptability: Saccharomyces boulardii and Pseudomonas fluorescens have different adaptability to the environment. Saccharomyces boulardii adapts better to acidic environments, while Pseudomonas fluorescens prefers neutral or slightly alkaline environments. If the ratio of the two is not appropriate, the environmental conditions will be unfavorable to one side, thus affecting the activity of the strain and the stability of fermentation. If the acidic environment is too strong, it will inhibit the activity of Pseudomonas fluorescens and affect its role in fermentation.

[0067] Bacterial competition: If the proportion of Saccharomyces boulardii is too high, it will consume a large amount of sugar in the bottom pot water, resulting in insufficient nutrition sources for Pseudomonas fluorescens, thereby inhibiting its growth and metabolic activities. Conversely, if the proportion of Pseudomonas fluorescens is too high, they will compete with Saccharomyces boulardii for oxygen and nutrients, affecting the smooth progress of the fermentation process and resulting in reduced alcohol production.

[0068] Unstable fertilizer quality: An inappropriate ratio of the two bacteria will lead to unstable products during the fermentation process. For example, when there are too many Saccharomyces boulardii, the alcohol and carbon dioxide produced during the fermentation process make the environment unfavorable for the growth of Pseudomonas fluorescens, resulting in uneven effective ingredients in the fertilizer. The liquid fertilizer produced in this way has quality fluctuations and cannot stably provide the nutrients required by plants.

[0069] A reasonable ratio of strains is essential to ensure the smooth progress of the fermentation process. The roles of Saccharomyces boulardii and Pseudomonas fluorescens in fermentation are complementary. Saccharomyces boulardii produces alcohol by fermenting sugars, while Pseudomonas fluorescens plays a positive role by degrading organic matter, promoting plant growth and inhibiting harmful microorganisms. If the ratio of the two is not appropriate, the fermentation process will be unstable, undesirable by-products will be produced, and even the quality and efficiency of the fertilizer will be affected. Therefore, in the actual fermentation process, accurately controlling the ratio of the two bacteria is the key to achieving the best fermentation effect and fertilizer quality.

[0070] Comparative Example 3: The difference from Example 1 is that the secondary fermentation in step (2) is omitted. The other steps and conditions are the same as those in Example 1.

[0071] In the actual fermentation process, if the secondary fermentation in step (2) is omitted, the following adverse effects will occur: Incomplete fermentation: Secondary fermentation is usually carried out to further decompose the remaining fermentable substances and assist in completing the sugars and other organic substances that were not fully converted during the primary fermentation process. After omitting the secondary fermentation, the fermentation is not fully carried out, and the remaining fermentable substances (such as unconverted sugars) will affect the quality of the final product and lead to an incomplete fermentation process, leaving too many untreated substances.

[0072] Excessive by-products: After primary fermentation, many yeasts and bacteria are still producing by-products such as alcohol, carbon dioxide, esters, and organic acids. If the secondary fermentation is omitted, these by-products will accumulate, affecting the quality of the final product. For example, if the concentration of alcohol is too high, the by-products of over-fermentation will affect the stability of the fertilizer and the adaptability of plants.

[0073] Reduced fertilizer effectiveness: Secondary fermentation helps to further convert organic matter and generate more components beneficial to plants, such as amino acids and vitamins. Omitting this process results in incomplete or unbalanced nutrient components in the fertilizer, reducing its effectiveness for plants. Without secondary fermentation, the nutrient components of the fertilizer cannot be fully optimized, affecting the absorption and growth of plants.

[0074] Unstable liquid fertilizer: Secondary fermentation not only helps to complete the fermentation process but also further stabilizes the chemical composition of the fertilizer. If this step is omitted, the liquid fertilizer is prone to stratification or precipitation due to insufficient fermentation, resulting in poor stability of the fertilizer and inconsistent effects during use.

[0075] Microbial community imbalance: Secondary fermentation is an important step in adjusting and optimizing the microbial community, which helps to promote the growth of beneficial microorganisms and inhibit harmful microorganisms. If this stage is omitted, it will lead to the accumulation of harmful microorganisms in the fermentation broth, inhibiting the activity of beneficial bacteria, resulting in a decline in the quality of the liquid fertilizer and even triggering adverse microbial competition or contamination.

[0076] Secondary fermentation is an important step in optimizing the quality, stability, and effectiveness of the fermentation broth. If this link is omitted, it will lead to a series of problems such as incomplete fermentation process, insufficient nutrient components, excessive by-products, and unstable liquid fertilizer, thus affecting the quality of the fertilizer and its effect on plants. Therefore, secondary fermentation is crucial for ensuring the final quality and effect of liquid fertilizers.

[0077] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A fermentation method for preparing fertilizer using the bottom pot water of wine brewing, characterized in that, The method comprises the following steps: (1) Raw material pretreatment: separating solid residues from the brewing bottom pot water through solid-liquid separation, adjusting the pH to 5.5 - 6.0, and then performing heavy metal adsorption; (2) Directed fermentation with a compound microbial agent: Primary fermentation: inoculate with a composite microbial agent, conduct aerobic fermentation, with the dissolved oxygen content DO ≥ 4 mg / L, and ferment at 38 - 40 °C for 10 - 14 h; the composite microbial agent is composed of Saccharomyces boulardii ‌Saccharomyces cerevisiae var. boulardii and Pseudomonas fluorescens Pseudomonas fluorescens ; Secondary fermentation: after aerobic fermentation ends, perform micro-aerobic fermentation with the dissolved oxygen content DO being 0.5 - 1 mg / L, ferment at 33 - 35 °C for 60 - 72 h, and add phosphate rock powder before micro-aerobic fermentation; Tertiary fermentation: after micro-aerobic fermentation ends, perform anaerobic fermentation, ferment at 28 - 30 °C for 90 - 96 h; (3) Nutrient strengthening and stabilization: after anaerobic fermentation ends, obtain the fermentation broth, add urea, phosphate rock powder, and potassium sulfate to make nitrogen, phosphorus, and potassium reach the set ratio; then add EDTA chelated trace elements and mix evenly; (4) Finished product preparation: separate the solid and liquid of the solution obtained in step (3) to remove the microbial residues, sterilize, and add xanthan gum to obtain the liquid fertilizer.

2. The fermentation method for preparing fertilizer using the bottom water of wine brewing according to claim 1, characterized in that, In step (1), the initial pH of the brewing bottom pot water is 4.0 - 4.5, and the ethanol content is 2 - 3 v / v%.

3. The fermentation method for preparing fertilizer using the bottom water of wine brewing as claimed in claim 1, characterized in that, In step (1), the heavy metal adsorption is carried out by using modified bentonite adsorption and chelating bacteria Bacillus subtilis fixation, and the lead content in the finally obtained finished product is ≤ 3 mg / kg, and the cadmium is ≤ 0.5 mg / kg.

4. The fermentation method for preparing fertilizer using the bottom water of the wine-making pot as claimed in claim 1, wherein, In the primary fermentation of step (2), the ratio of viable bacteria of Saccharomyces boulardii to Pseudomonas fluorescens is 6:(3 - 5); in the primary fermentation of step (2), ferment at 40 °C for 12 h.

5. The fermentation method for preparing fertilizer using the bottom water of wine brewing pot according to claim 1, characterized in that, In the secondary fermentation of step (2), ferment at 35 °C for 72 h.

6. The fermentation method for preparing fertilizer using the bottom water of wine brewing pot according to claim 1, characterized in that, In the tertiary fermentation of step (2), ferment at 30 °C for 96 h.

7. The fermentation method for preparing fertilizer using the bottom water of wine brewing according to claim 1, characterized in that, In step (3), the EDTA chelated trace elements are EDTA chelated zinc and EDTA chelated iron, and the addition amount of the EDTA chelated trace elements is 0.1 w / w%.

8. The fermentation method for preparing fertilizer using the bottom water of wine brewing according to claim 1, characterized in that, In step (4), the addition amount of the xanthan gum is 0.1 w / w%, which means the weight of the added xanthan gum is 0.1% of the weight of the solution after sterilization.

9. The liquid fertilizer prepared by the method according to any one of claims 1 to 8, characterized in that, The content of humic acid in the liquid fertilizer is ≥5 w / w%, and the amino acid content is ≥8 g / L.

10. A system for preparing fertilizer using the bottom water of a brewing pot, characterized in that, The system comprises a pretreatment unit, a fermentation unit, a nutrient regulation unit, and a post-treatment unit; The pretreatment unit comprises a pH adjustment tank, a raw material tank, a solid-liquid separation sieve, and a heavy metal adsorption column connected in sequence; The fermentation unit comprises a compound microbial agent activation tank, a primary fermentation tank connected to the heavy metal adsorption column, a secondary fermentation tank, and a tertiary fermentation tank connected in sequence, and a dissolved oxygen regulation system connected to the three fermentation tanks. The dissolved oxygen regulation system comprises an air compressor and a dissolved oxygen / temperature adjustment device; The nutrient regulation unit comprises a nitrogen, phosphorus, and potassium supplement tank connected to the primary fermentation tank and a chelating agent sprayer connected to the tertiary fermentation tank; The post-treatment unit comprises a centrifuge connected to the tertiary fermentation tank and a pasteurizer, a concentration device, a storage device, and a finished product tank connected to the centrifuge in sequence.

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