A biomass nutrient solution applied to sewage biochemical treatment, a preparation device and a preparation method thereof

Abstract

The application discloses a kind of biomass nutrient solution applied to sewage biochemical treatment and preparation method thereof, belong to sewage treatment and biomass resource utilization technical field.The biomass nutrient solution is by brewery fermentation liquid precipitate slurry, vinegar factory precipitate slurry, beer fruit juice beverage factory fermentation residue slurry, dairy factory expired liquid milk and latex sludge, one or more of kitchen disposal industry concentrated liquid as raw material, by compound microbial inoculant fermentation, solid-liquid separation, secondary compounding is obtained.The preparation method includes raw material feeding, adds inoculant, stirring mixes, fermentation, solid-liquid separation, semi-finished product modulation and secondary compounding and the like steps.The product of the application COD≥300,000 mg / L, B / C ratio≥0.5, solidification point≤-18 DEG C, microbial utilization rate≥90%, cost is reduced by 10%~30% compared with sodium acetate.The application solves the problems that existing carbon source has poor safety, poor low-temperature adaptability, high cost and is easy to damage biochemical system, realizes the resource utilization of industrial organic waste.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment and biomass resource utilization technology, specifically relating to a biomass nutrient solution for wastewater biochemical treatment and its preparation method, as well as a treatment device for implementing the preparation method. This invention is particularly suitable for biological denitrification treatment systems for municipal wastewater, industrial wastewater, and rural domestic sewage, and is especially suitable for use in cold, high-altitude regions during winter. Background Technology

[0002] With the rapid pace of industrialization and urbanization in my country, wastewater discharge has continued to increase, leading to increasingly serious eutrophication problems in water bodies. To address this environmental issue, the State Council issued the "Water Pollution Prevention and Control Action Plan," which sets higher requirements for nitrogen and phosphorus removal in wastewater treatment plants. Statistics show that over 90% of wastewater treatment plants in my country use biological treatment methods, with biological denitrification being the core process for nitrogen removal. Biological denitrification mainly involves the nitrification and denitrification processes of microorganisms to convert ammonia nitrogen in water into nitrogen gas for removal.

[0003] In biological nitrogen removal, the denitrification stage requires a sufficient carbon source as an energy source and raw material for microorganisms and cell synthesis. When the carbon-to-nitrogen ratio (C / N ratio) in wastewater is insufficient, the activity of denitrifying bacteria is inhibited, leading to a significant decrease in denitrification efficiency. Studies have shown that wastewater treatment plant effluent still contains 70%–80% nitrate nitrogen, mainly due to insufficient carbon source for denitrification. The technical approaches to solving this problem mainly fall into two categories: one is to increase the volume of the anoxic zone, but this requires expansion of the wastewater treatment plant, resulting in huge infrastructure investments; the other is to add an exogenous carbon source (nutrient solution) to the system, a method that has proven to be more economical and feasible in practice.

[0004] Currently, commonly used carbon sources (nutrient solutions) on the market can be mainly divided into the following categories: (a) Single carbon source Methanol: Methanol has a high denitrification rate and relatively low operating costs, but it is toxic, classified as a hazardous chemical, and is flammable and explosive. It poses significant safety risks during storage, transportation, and use, and also has potential health hazards to operators.

[0005] Sodium acetate: Sodium acetate has a high denitrification rate and stable effect, but it is expensive and produces a high sludge output. Particularly noteworthy is that liquid sodium acetate has a high water content and a high freezing point (it begins to freeze at around 0°C), making it unsuitable for normal addition during winter in cold regions such as Northwest and Northeast my country, severely limiting its application.

[0006] Glucose: Glucose has a low cost, but its denitrification rate is greatly affected by water quality. It can easily cause bacteria to multiply in large quantities, leading to the accumulation of nitrite, which affects the quality of the effluent and can easily damage the microbial community structure of the biological system.

[0007] (ii) Composite carbon source Composite carbon sources consist of two or more effective carbon source components, requiring that the components be compatible and free from chemical reactions and safety risks. Although current composite carbon source products on the market combine the advantages of various carbon sources to some extent, they still generally suffer from problems such as high cost and strong dependence on raw materials.

[0008] (III) Existing biomass nutrient solution In recent years, the preparation of nutrient solutions from biomass waste has become a research hotspot. Some technical solutions attempt to prepare carbon sources using kitchen waste and agricultural waste (such as straw). For example, patent CN-119797596-A discloses a method for preparing a composite carbon source using agricultural waste (straw) as raw material through enzymatic hydrolysis. However, existing technologies still have the following shortcomings: The raw material source is singular, and the conditions for the use of wastewater are quite stringent, especially the requirements for pH value and temperature are high; When fermentation conditions are not met, microorganisms need a long time to adjust and adapt, which reduces biodegradation efficiency. Additional packaging during transportation and use generates a large amount of waste, increasing the environmental burden. The lack of consideration for the product's low-temperature performance makes it unable to meet the usage needs of cold regions.

[0009] In conclusion, developing a safe, efficient, economical, and low-temperature-suitable biomass nutrient solution and its preparation method is of significant practical importance and has broad application prospects. Summary of the Invention

[0010] Technical issues This invention aims to overcome the shortcomings of existing technologies and provide a biomass nutrient solution, treatment device, and preparation method for wastewater biochemical treatment. Specifically, this invention addresses the following technical problems: 1. To address the safety hazards of existing methanol nutrient solutions, which are toxic, flammable, and explosive, and to provide a safe, non-toxic biomass nutrient solution with a high flash point; 2. To address the problem that existing sodium acetate nutrient solutions have a high freezing point and are unsuitable for winter application in northern regions, a nutrient solution with a low freezing point, does not freeze in winter, and has good fluidity is provided. 3. To address the issues of high cost and high sludge yield of existing sodium acetate nutrient solutions, a lower-cost nutrient solution with less sludge production can be provided by using industrial waste as raw material. 4. To solve the problem that existing glucose nutrient solutions easily cause nitrite accumulation and affect the quality of effluent, a nutrient solution is provided that can enhance the diversity of microbial communities, stabilize the denitrification rate, and not damage the system ecology. 5. Realize the resource utilization of organic waste from industries such as wineries, vinegar factories, beverage factories, dairy factories, and kitchen waste, turning waste into treasure.

[0011] Technical solution To achieve the above objectives, the present invention provides the following technical solutions.

[0012] In a first aspect, a method for preparing a biomass nutrient solution for wastewater biochemical treatment includes the following steps: (1) Raw material feeding: The industrial organic waste liquid raw material is directly added to the fermentation filter tank equipped with a stirrer without filtration; (2) Adding microbial agents and auxiliary materials: Add compound microbial agents, sodium chloride and molasses to the fermentation filter tank; (3) Stirring and mixing: Start the stirrer to thoroughly mix the raw materials and inoculum. (4) Fermentation process: control the fermentation temperature and time, and determine that the fermentation is complete when the COD value of the fermentation liquid is ≥150,000 mg / L; (5) Solid-liquid separation: The mixture after fermentation is completed is subjected to solid-liquid separation to obtain supernatant and filter residue; (6) Preparation of semi-finished product: Detect the pH value of the supernatant and adjust it to 7.5-8.5; (7) Secondary compounding: Using molasses as a COD regulator, the supernatant is adjusted to COD≥300,000 mg / L to obtain the biomass nutrient solution.

[0013] Preferably, in step (1), the industrial organic waste liquid raw material is selected from one or more of the following: fermentation liquid sedimentation slurry from wineries, sedimentation slurry from vinegar plants, fermentation slurry from beer, juice and beverage plants, expired liquid milk and latex sludge from dairy plants, and concentrated liquid from the kitchen waste disposal industry.

[0014] Preferably, in step (2), the compound microbial agent includes lactic acid bacteria, yeast, acetic acid bacteria, formic acid bacteria, Bacillus, EM bacteria and photosynthetic bacteria; the amount of compound microbial agent and excipients added per ton of raw material is: 50g of lactic acid bacteria, 150g of yeast, 55g of acetic acid bacteria, 30g of formic acid bacteria, 200g of a mixture of Bacillus and EM bacteria, 50g of sodium chloride, 500-1000g of molasses, and the amount of photosynthetic bacteria added is flexibly adjusted according to the seasonal temperature: reduce or not add when the temperature is high in summer, and add 30-50g per ton of raw material when the temperature is low in winter.

[0015] Preferably, in step (4), the fermentation process is as follows: the fermentation temperature is controlled at 30-45℃, the fermentation time is 48-70 hours, and the stirring is turned on for 10 minutes every 12 hours.

[0016] Preferably, the filter residue obtained in step (6) is dried and then used to prepare organic fertilizer or high-efficiency compound fertilizer.

[0017] Preferably, the industrial organic waste liquid raw material is tested for BOD, COD, pH and density data before feeding, and the raw material ratio is adjusted according to the test results.

[0018] Preferably, when starch-based raw materials are used, the amount of Bacillus added to the compound microbial agent is increased to 300g / ton of raw material.

[0019] Preferably, when using protein-based raw materials, the amount of yeast and lactic acid bacteria added to the compound microbial agent is increased accordingly.

[0020] Preferably, the fermentation process adopts a continuous fermentation method, that is, continuous feeding and continuous discharging.

[0021] Preferably, the stirring is performed by bottom aeration stirring instead of mechanical stirring.

[0022] Secondly, a processing apparatus for implementing the above-described preparation method includes: (The apparatus is connected in sequence) Raw material tank, used to store one or more industrial organic waste liquid raw materials; A fermentation filter tank, the inlet of which is connected to the outlet of the raw material tank, is equipped with a stirrer driven by a stirring motor, a bacteria inlet and a temperature control device, for the fermentation reaction of raw materials and compound microbial agents; A solid-liquid separation device, the inlet of which is connected to the outlet of the fermentation filter tank, is used to separate the solid and liquid components of the mixture after fermentation. The dispensing tank has its inlet connected to the liquid outlet of the solid-liquid separation equipment and is used to temporarily store the supernatant after filtration. The compounding tank has its inlet connected to the outlet of the dispensing tank. The compounding tank is equipped with a stirrer driven by a stirring motor. The compounding tank is also equipped with an additive inlet, which is connected to a molasses diluent tank and other additive tanks respectively, for secondary compounding of the supernatant. The finished product tank, whose inlet is connected to the outlet of the compounding tank, is used to store the final finished product.

[0023] Preferably, the solid-liquid separation equipment is one of a plate and frame filter press, a centrifugal separator, or a membrane filtration device.

[0024] The solid-liquid separation equipment is a plate and frame filter press, which has a compressed air inlet at the top and a filter residue outlet and a supernatant outlet at the bottom.

[0025] Preferably, the fermentation filter tank is equipped with a heating and insulation jacket; the agitator is a mechanical agitator or a bottom aeration agitator; and the temperature control device includes a heater, a cooling coil, and a temperature sensor.

[0026] Preferably, the raw material tank includes multiple independent raw material tanks, each used to store different types of industrial organic waste liquid raw materials; each raw material tank is equipped with a BOD / COD / PH detection port, and each raw material tank is connected to the fermentation filter tank through a raw material pump and pipeline.

[0027] Preferably, the compounding tank is equipped with an online COD detector; the compounding tank is connected to the finished product tank via a transfer pump.

[0028] Thirdly, a nutrient solution prepared using the above-described preparation method.

[0029] Compared with the prior art, the present invention has the following beneficial effects: 1. Significantly improved safety: The product of this invention does not contain methanol or other toxic and harmful substances, is safe and non-toxic, has a high flash point, and poses no risk of flammability or explosion. It is safe and reliable during storage, transportation and use.

[0030] 2. Excellent low-temperature adaptability: The product has a freezing point of ≤-18℃, does not freeze or clump in winter, and has good fluidity, which completely solves the problem that traditional carbon sources such as sodium acetate cannot be added normally in cold northern regions during winter.

[0031] 3. Significantly reduced economic costs: This invention uses industrial organic waste as the main raw material, which has a stable source and low price, and can even be obtained for free in some areas. Compared with sodium acetate, the treatment cost is reduced by 10% to 30%.

[0032] 4. High microbial utilization rate: The product is rich in nutrients such as small molecule organic acids and alcohols that are easily utilized by microorganisms. The microbial utilization rate is ≥90%, which is higher than that of sodium acetate (about 85%), and can save 20% to 50% of the nutrient dosage.

[0033] 5. Low sludge production: The sludge production rate of the product of this invention is lower than that of sodium acetate, which can significantly reduce the solid waste disposal costs of sewage treatment plants.

[0034] 6. Good stability of the biochemical system: The product of this invention does not damage the microbial ecology of the sewage treatment system, can enhance the diversity of the microbial community, stabilize the denitrification rate, and will not lead to the accumulation of nitrite.

[0035] 7. Significant resource utilization benefits: It turns organic waste generated by wineries, vinegar factories, beverage factories, dairy factories, and catering industries into valuable resources, which is in line with the national policy orientation of pollution reduction and carbon reduction and circular economy, and achieves zero waste throughout the entire process. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in this disclosure, the accompanying drawings used in some embodiments of this disclosure will be briefly described below. Obviously, the drawings described below are only drawings of some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual size of the product, the actual flow of the method, the actual timing of the signals, etc. involved in the embodiments of this disclosure.

[0037] Figure 1 : Flowchart of the biomass nutrient solution production and compounding process of this invention.

[0038] Figure 2 : Schematic diagram of the configuration structure of the raw material tank and fermentation filter tank of the present invention.

[0039] Figure 3 : Schematic diagram of the connection structure between the plate and frame filter press and the dispensing tank of the present invention.

[0040] Figure 4 : Schematic diagram of the connection structure between the compounding area and the finished product tank in this invention.

[0041] In the diagram: 1-Raw material tank, 1.1-Raw material inlet, 1.2-BOD / COD / PH detection port, 1.3-Raw material pump, 1.4-Pipeline, 2-Fermentation filter tank, 2.1-Agitator, 2.2-Inoculum inlet, 2.3-Agitator motor, 2.4-Heating and insulation jacket; 3-Plate and frame filter press, 3.1-Compressed air inlet, 3.2-Filter residue outlet, 3.3-Supernatant outlet, 4-Dispensing tank, 5-Compound tank, 5.1-Online COD analyzer, 5.2-Detection fixture, 5.3-Agitator motor, 5.4-Additive inlet, 5.5-Transfer pump, 5.6-Molten molasses dilution tank, 5.7-Other additive tanks, 6-Finished product tank, 7-Product outlet. Detailed Implementation

[0042] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0043] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0044] The present invention will be further described in detail below through embodiments.

[0045] (a) Product Plan To achieve the above objectives, the present invention provides a biomass nutrient solution for use in the biochemical treatment of wastewater.

[0046] Specifically, a biomass nutrient solution for wastewater biochemical treatment is prepared from raw materials containing the following components through fermentation with compound microbial agents, solid-liquid separation, and secondary compounding: 1. Main raw materials The main raw material is selected from one or more of the following industrial organic waste liquids: The fermentation broth sediment slurry of a winery (rich in starch, protein, and incompletely fermented sugars); Vinegar factory sediment slurry (rich in acetic acid, starch, and cellulose); Fermentation residue slurry from beer, juice, and beverage factories (rich in sugars, pectin, and organic acids); Expired liquid milk and latex sludge from dairy plants (rich in lactose, milk protein, and fat); Concentrated liquid produced in the food waste disposal industry (rich in starch, oil, protein, and salt).

[0047] All the above raw materials are in liquid or slurry form and are added directly to the fermentation filter tank without filtration. This feeding method retains the solids and microorganisms in the raw materials, which is beneficial for the start-up and progress of the subsequent fermentation process. In addition, it can also be used for high-concentration wastewater from starch processing plants, non-toxic fermentation waste liquid from pharmaceutical plants, waste honey from sugar factories, and wastewater from soy product processing, etc.

[0048] 2. Compound microbial inoculants The compound microbial agent used in this invention must contain the following seven types of functional bacteria: Lactic acid bacteria convert sugars into lactic acid, lowering the pH and inhibiting other bacteria. At the same time, lactic acid is a high-quality small-molecule carbon source.

[0049] Yeast: converts sugars into ethanol and CO2, and the ethanol can be further oxidized into small molecule acids.

[0050] Acetic acid bacteria: oxidize ethanol into acetic acid.

[0051] Formic acid bacteria: convert complex organic matter into formic acid, which is a preferred carbon source for the denitrification process.

[0052] Bacillus: Secretes extracellular enzymes such as amylase, protease, and lipase to break down large molecules of starch, protein, and fat into smaller molecules of sugar, amino acids, and fatty acids, providing substrates for other bacterial species.

[0053] EM bacteria (Effective Microorganisms): These are composed of photosynthetic bacteria, lactic acid bacteria, yeast, and other microorganisms. They can produce growth factors such as vitamins and antioxidants, promoting the synergistic effect of the entire microbial community.

[0054] Photosynthetic bacteria: utilize light energy and organic matter to synthesize substances such as amino acids and nucleic acids, thereby enhancing the biological activity of fermentation products.

[0055] Based on per ton of raw material, the dosage of each microbial agent is as follows: 50g lactic acid bacteria, 150g yeast, 55g acetic acid bacteria, 30g formic acid bacteria, 200g mixture of Bacillus and EM bacteria, 50g sodium chloride, and 500-1000g molasses. The dosage of photosynthetic bacteria should be adjusted flexibly according to seasonal temperature: reduce or omit the addition during the high temperatures of summer, and add 30-50g per ton of raw material during the low temperatures of winter.

[0056] 3. Product performance indicators COD value: ≥300,000 mg / L (preferably 300,000 to 400,000 mg / L) A BOD5 to COD ratio (B / C ratio) ≥0.5 indicates excellent biodegradability. Freezing point: ≤-18℃, ensuring it remains fluid during severe winters. Microbial utilization rate: ≥90% Sludge yield: lower than sodium acetate (<0.35 kg MLSS / kg COD) Appearance: Brownish-brown liquid with a slightly fermented aromatic odor. pH value: 7.5–8.5, compatible with the pH environment of wastewater biological treatment systems. Density: 1.05~1.15 g / cm³ (25℃) (II) Methodology This invention also provides a method for preparing the biomass nutrient solution, characterized by employing a two-step process of "one-step fermentation + two-step compounding," specifically including the following steps: Step 1: Raw material pretreatment and feeding Industrial organic wastewater collected from wineries, vinegar factories, beverage factories, dairy factories, and the catering industry is packaged into raw material tanks. Basic data such as BOD, COD, pH, and density are tested, and the raw material ratio is adjusted based on the test results. The liquid raw materials are then directly added to a fermentation and filtration tank equipped with a stirrer, without filtration during the initial feeding.

[0057] Step 2: Add microbial agents and excipients Add compound microbial inoculant, sodium chloride, and molasses to the fermentation filter tank. The dosage per ton of raw material is: 50g lactic acid bacteria, 150g yeast, 55g acetic acid bacteria, 30g formic acid bacteria, 200g mixture of Bacillus and EM bacteria, 50g sodium chloride, and 500-1000g molasses. Adjust the amount of photosynthetic bacteria according to the season: add less or none in summer, and add 30-50g per ton in winter.

[0058] Step 3: Mix Start the mixer to thoroughly mix the raw materials and inoculum, ensuring that the inoculum and substrate are in full contact.

[0059] Step 4: Fermentation process Temperature control: The fermentation temperature should be controlled at 30–45℃, preferably 35–40℃. Hot water or steam can be circulated through the jacket of the fermentation filter tank for heating, and cooling water can be used for cooling in summer.

[0060] Stirring control: Turn on the stirrer for 10 minutes every 12 hours to avoid over-stirring and damaging the bacterial flocs, while ensuring uniform mixing and gas exchange.

[0061] Fermentation time: 48-70 hours.

[0062] Step 5: Determining the Fermentation Endpoint The COD value was measured after 48 hours. Fermentation was considered complete when the COD was ≥ 150,000 mg / L.

[0063] Step 6: Solid-liquid separation After fermentation, the mixture is subjected to solid-liquid separation to obtain a supernatant and a filter residue. Solid-liquid separation can be performed using a plate and frame filter press, a centrifuge, or a membrane filtration system. The filter residue, after drying, can be used to prepare organic fertilizer or high-efficiency compound fertilizer, achieving zero waste throughout the entire process.

[0064] Step 7: Preparation of semi-finished products Detect the pH value of the supernatant after filtration, and adjust the pH to 7.5-8.5 with an alkaline solution (such as sodium hydroxide solution) or an acidic solution.

[0065] Step 8: Secondary compounding (finished product preparation) Using molasses as a COD regulator, the supernatant is adjusted to a COD ≥ 300,000 mg / L, preferably 300,000–400,000 mg / L, using a molasses dilution solution (molasses:water = 1:0.5~2), thus obtaining the biomass nutrient solution. In winter, the product should be formulated to prevent freezing and clumping according to the actual requirements of the application site. The mixing ratio is determined based on the wastewater treatment process, influent water quality data, and discharge standards.

[0066] (III) Equipment Scheme The present invention also provides a processing apparatus for implementing the above-described preparation method, characterized in that it comprises: connected in sequence: Raw material tank 1 is used to store one or more industrial organic waste liquid raw materials; Fermentation filter tank 2, whose inlet is connected to the outlet of the raw material tank, is equipped with a stirrer 2.1 driven by a stirring motor 2.3, a bacteria inlet 2.2 and a temperature control device, for the fermentation reaction of raw materials and compound microbial agents; A solid-liquid separation device, the inlet of which is connected to the outlet of the fermentation filter tank, is used to separate the solid and liquid components of the mixture after fermentation. The dispensing tank 4 has its inlet connected to the liquid outlet of the solid-liquid separation equipment and is used to temporarily store the supernatant after filtration. The compounding tank 5 has its inlet connected to the outlet of the dispensing tank. The compounding tank 5 is equipped with a stirrer driven by a stirring motor 5.3. The compounding tank 5 is also equipped with an additive inlet. The additive inlet 5.4 is connected to the molasses dilution tank 5.6 and other additive tanks 5.7 respectively, for secondary compounding of the supernatant. Finished product tank 6, whose inlet is connected to the outlet of the compounding tank, is used to store the final finished product.

[0067] The solid-liquid separation equipment is one of a plate and frame filter press, a centrifugal separator, or a membrane filtration equipment.

[0068] The solid-liquid separation equipment is a plate and frame filter press 3. The plate and frame filter press 3 is provided with a compressed air inlet 3.1 at the top and a filter residue outlet 3.2 and a supernatant outlet 3.3 at the bottom.

[0069] The fermentation filter tank 2 is equipped with a heating and insulation jacket 2.4; the agitator is a mechanical agitator or a bottom aeration agitator; and the temperature control device includes a heater, a cooling coil, and a temperature sensor.

[0070] The raw material tank includes multiple independent raw material tanks, which are used to store different types of industrial organic waste liquid raw materials. Each raw material tank is equipped with a BOD / COD / PH detection port 1.2, and each raw material tank is connected to the fermentation filter tank 2 through a raw material pump 1.3 and a pipeline 1.4.

[0071] The compounding tank 5 is equipped with an online COD detector 5.1; the compounding tank 5 is connected to the finished product tank 6 via a transfer pump 5.5.

[0072] Raw material tanks: Used to store one or more industrial organic waste liquid raw materials. The raw material tanks include multiple independent tanks (e.g., 3-10), each used to store different types of industrial organic waste liquid. Each raw material tank is equipped with a BOD / COD / pH detection port, a transfer pump, and piping to the fermentation and filtration tank. An online COD / pH analyzer is optional.

[0073] Fermentation filter tank: Its inlet is connected to the outlet of the raw material tank. The fermentation filter tank is equipped with a stirrer and a temperature control device for the fermentation reaction of the raw material and the compound microbial agent. The volume of the fermentation filter tank is preferably 10-100 cubic meters. The stirrer is a mechanical stirrer (top mechanical stirrer, anchor type or paddle type, speed adjustable from 0-150 rpm) or a bottom aeration stirrer (suitable for easily foaming raw materials). The temperature control device includes a heater (jacket or coil), a cooling coil, a temperature sensor and an automatic control cabinet, used to control the fermentation temperature at 30-45℃±2℃. A pH meter and dissolved oxygen electrode are optional.

[0074] Solid-liquid separation equipment: Its inlet is connected to the outlet of the fermentation filter tank, and it is used to separate the solid and liquid components of the mixture after fermentation. The solid-liquid separation equipment is a plate and frame filter press, a centrifuge, or a membrane filtration device. When a plate and frame filter press is used, its solid outlet is connected to the organic fertilizer preparation unit (including a dryer, a crusher, and a mixer).

[0075] Dispensing tank: Its inlet is connected to the liquid outlet of the solid-liquid separation equipment, and it is used to temporarily store the supernatant after filtration. The volume is generally 0.5-1 times that of the fermentation filter tank, and it is equipped with a stirrer and a pH adjuster dosing port.

[0076] Compounding tank: Its inlet is connected to the outlet of the dispensing tank, and it is equipped with a molasses additive inlet for secondary compounding of the supernatant. The compounding tank is equipped with a high-precision metering pump for precise control of the molasses addition ratio, and is also equipped with a stirrer and an online COD detector (or sampling port).

[0077] Finished product tank: Its inlet is connected to the outlet of the compounding tank and is used to store the final finished product. The volume of the finished product tank is determined according to sales and transportation needs (e.g., 30-100 m³), ​​and it can be equipped with a heating and insulation jacket (for winter antifreeze) and a filling port.

[0078] (iv) Mechanism of Operation 1. Principle of Co-fermentation This invention utilizes the synergistic metabolic effect of compound microbial agents at 30–45°C to efficiently convert complex macromolecular organic matter in industrial waste into small-molecule carbon sources that are preferentially utilized by denitrifying bacteria. Step 1 (hydrolysis): Bacillus secretes amylase, protease, and lipase to break down large molecules of starch, protein, and fat into smaller molecules of sugar, amino acids, and fatty acids.

[0079] Step 2 (glycolysis and alcohol production): Yeast converts sugars into pyruvate via the EMP pathway, which is then decarboxylated to produce ethanol.

[0080] The third step (acid production): Lactic acid bacteria convert sugars into lactic acid; acetic acid bacteria and formic acid bacteria oxidize ethanol, lactic acid, etc. into short-chain volatile fatty acids (VFAs) such as acetic acid and formic acid.

[0081] Step 4 (Synergy and Promotion): The vitamins, nucleic acids, growth factors and other factors produced by EM bacteria promote the growth and metabolism of all bacterial species; photosynthetic bacteria use the organic acids and light energy produced by metabolism to synthesize amino acids, coenzymes and other substances, thereby improving the nutritional value and biological activity of the products.

[0082] This synergistic metabolic network results in the final fermentation products being rich in VFAs such as acetic acid, propionic acid, butyric acid, lactic acid, and formic acid, as well as small amounts of alcohols such as ethanol and propanol. These substances have small molecular weights and simple structures, allowing denitrifying bacteria to rapidly transport and utilize them across the membrane without secreting inducing enzymes, thus achieving a microbial utilization rate of over 90%.

[0083] 2. Principle of Secondary Compounding The COD of basic fermentation products is typically 150,000-200,000 mg / L, with a high B / C ratio (≥0.6). However, the COD equivalent is still relatively low for commercial applications (transportation costs, storage space). By adding a high-concentration (COD 800,000-1,200,000 mg / L) molasses dilution, the COD of the final product can be increased to over 300,000 mg / L. Furthermore, molasses, in addition to sucrose (which requires further decomposition), contains abundant minerals (such as K, Ca, Mg, Fe) and vitamins, compensating for the potential deficiency of trace elements in industrial waste. This combination of "fermentation products (high B / C ratio, low molecular weight acid) + molasses (high COD, trace elements)" optimizes the product's cost-effectiveness.

[0084] 3. Low-temperature adaptability principle The freezing point of a liquid product depends primarily on the type and concentration of its solute. Small molecule organic acids (such as acetic acid and propionic acid) and alcohols (such as ethanol and propanol) form hydrogen bonds with water molecules, significantly disrupting the water crystallization process and lowering the freezing point. This invention controls fermentation process parameters (especially the ratio of inoculum and temperature) to achieve a higher proportion of C2-C4 small molecule acids and alcohols in the product. Simultaneously, the molasses used in the blend contains a large amount of reducing sugars and fructose, which also help lower the freezing point. The synergistic effect of these three factors lowers the product's freezing point to below -18°C, far lower than sodium acetate (approximately -5°C) and glucose solution (approximately -3°C), completely solving the problem of winter addition.

[0085] Example 1 raw material: Winery fermentation liquid sediment slurry: 1 ton Compound probiotic agent: 50g lactic acid bacteria, 150g yeast, 55g acetic acid bacteria, 30g formic acid bacteria, 200g mixture of Bacillus and EM bacteria. Other ingredients: 50g sodium chloride, 800g molasses, 20g photosynthetic bacteria Preparation steps: One ton of fermentation liquid sediment slurry from the winery was directly added to a fermentation filter tank equipped with a stirrer, without filtration.

[0086] Add 50g of lactic acid bacteria, 150g of yeast, 55g of acetic acid bacteria, 30g of formic acid bacteria, 200g of a mixture of Bacillus and EM bacteria, 50g of sodium chloride, 800g of molasses, and 20g of photosynthetic bacteria to the fermentation filter tank.

[0087] Turn on the mixer and mix thoroughly.

[0088] Control the fermentation temperature at 35℃ and ferment for 60 hours, stirring for 10 minutes every 12 hours.

[0089] After 60 hours, the COD was measured at 162,000 mg / L, reaching the fermentation endpoint.

[0090] The fermentation broth is separated into solid and liquid components using a plate and frame filter press to obtain supernatant and filter residue.

[0091] The pH of the supernatant was found to be 6.8, and the pH was adjusted to 8.0 using sodium hydroxide solution.

[0092] Add molasses diluent (molasses:water = 1:1) to the adjusted supernatant to adjust the COD to 320,000 mg / L.

[0093] Product performance: COD: 320,000 mg / L B / C ratio: 0.51 pH: 8.0 Freezing point: -18℃ without freezing, good fluidity Appearance: Brownish-brown liquid with a slightly fermented aromatic odor; Density: 1.12 g / cm³.

[0094] Example 2 raw material: Vinegar plant sediment slurry: 0.5 tons 0.5 tons of expired liquid milk from a dairy factory. Compound microbial agent and excipients: Same as in Example 1 Preparation steps: 0.5 tons of sediment slurry from a vinegar factory and 0.5 tons of expired liquid milk from a dairy factory were mixed and then added to a fermentation and filtration tank.

[0095] The addition of microbial agents and excipients is the same as in Example 1.

[0096] The fermentation temperature was controlled at 40℃, and the fermentation time was 48 hours.

[0097] The COD level was measured at 158,000 mg / L after 48 hours.

[0098] The subsequent solid-liquid separation, pH adjustment, and compounding steps are the same as in Example 1.

[0099] Product performance: COD: 310,000 mg / L B / C ratio: 0.52 pH: 7.9 Freezing point: -20℃ without freezing Example 3 (Winter Formula) raw material: Fermentation residue slurry from a beer, juice, and beverage factory: 0.6 tons Concentrated liquid for food waste treatment industry: 0.4 tons Microbial agent: Same as in Example 1, but the amount of photosynthetic bacteria added is increased to 45g / ton. Preparation steps: After the raw materials are mixed, they are added to the fermentation and filtration tank.

[0100] The bacterial agent was added in the same way as in Example 1, but the amount of photosynthetic bacteria was increased to 45g.

[0101] The fermentation temperature was controlled at 38℃, and the fermentation time was 65 hours.

[0102] The fermentation endpoint COD was 155,000 mg / L.

[0103] The subsequent steps are the same as in Example 1.

[0104] Product performance: COD: 305,000 mg / L B / C ratio: 0.50 pH: 8.1 Freezing point: -22℃ without freezing Suitable for winter application in high-altitude and cold regions Example 4 (Alternative Raw Material Scheme) raw material: High-concentration wastewater from starch processing plant: 1 ton Inoculant adjustment: The amount of Bacillus added was increased to 300g / ton (because starch-based raw materials require more amylase). Preparation steps: Same as Example 1.

[0105] Product performance: COD: 315,000 mg / L B / C ratio: 0.51 Microbial utilization rate: 91% Example 5 (Alternative Separation Method) Raw materials and fermentation: Same as in Example 1 Solid-liquid separation methods: A centrifuge was used instead of a plate and frame filter press, with a rotation speed of 4000 r / min and a separation time of 15 minutes.

[0106] result: The supernatant recovery rate was 95%, and the product performance was basically the same as that of Example 1.

[0107] Example 6 (Continuous Fermentation Scheme) Raw materials: Fermentation broth, sediment, and slurry from a winery (continuous supply) Process parameters: Fermentation filter tank: continuous feeding, continuous discharging Duration of stay: 60 hours Temperature: 35~38℃ Microbial agent is added continuously according to the feed rate. result: After 30 days of stable operation, the average COD of the fermentation broth was 160,000 mg / L, and the COD of the product remained stable at 310,000–330,000 mg / L.

[0108] Comparative Example 1 (Performance comparison with sodium acetate) In the same wastewater treatment system (a municipal wastewater treatment plant with a treatment capacity of 50,000 tons / day), a comparative experiment was conducted by adding an equivalent COD amount (300,000 mg / L) of the product of Example 1 of this invention and sodium acetate, respectively. The operation period was 30 days, and the results are as follows: Application example: Processor operation instance Adopting attachment Figure 1-4The processing device shown is a production line with an annual output of 10,000 tons of biomass nutrient solution established by an environmental protection technology company in Hebei Province.

[0109] Device parameters: Raw material tanks: 5 units, each 20 m³, made of 304 stainless steel.

[0110] Fermentation filter tanks: 2 units, used alternately, each 30 m³, equipped with paddle agitator (11 kW), jacketed steam heating, and cooling coils.

[0111] Plate and frame filter press: XMYZ80 / 800 model, filtration area 80 m².

[0112] Packaging tank: 20 m³.

[0113] Compound mixing tank: 15 m³, with metering pump.

[0114] Finished product tanks: 3 units, each 30 m³, with insulation jackets.

[0115] Running result: It processes 60 tons of industrial organic waste liquid per day (from 3 wineries, 2 vinegar factories and 1 dairy factory in the surrounding area).

[0116] Daily production includes 20 tons of nutrient solution (COD 320,000 mg / L) and 12 tons of organic fertilizer (filter residue).

[0117] The annual output value is approximately 12 million yuan, the annual waste disposal volume is 18,000 tons, and the CO2 emissions are reduced by approximately 3,000 tons (calculated based on methane emissions from waste landfill).

[0118] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0119] The foregoing has described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0120] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a biomass nutrient solution for wastewater biochemical treatment, characterized in that, Includes the following steps: (1) Raw material feeding: The industrial organic waste liquid raw material is directly added to the fermentation filter tank equipped with a stirrer without filtration; (2) Adding microbial agents and auxiliary materials: Add compound microbial agents, sodium chloride and molasses to the fermentation filter tank; (3) Stirring and mixing: Start the stirrer to thoroughly mix the raw materials and inoculum. (4) Fermentation process: control the fermentation temperature and time, and determine that the fermentation is complete when the COD value of the fermentation liquid is ≥150,000 mg / L; (5) Solid-liquid separation: The mixture after fermentation is completed is subjected to solid-liquid separation to obtain supernatant and filter residue; (6) Preparation of semi-finished product: Detect the pH value of the supernatant and adjust it to 7.5-8.5; (7) Secondary compounding: Using molasses as a COD regulator, the supernatant is adjusted to COD≥300,000 mg / L to obtain the biomass nutrient solution.

2. The preparation method according to claim 1, characterized in that, In step (1), the industrial organic waste liquid raw materials are selected from one or more of the following: fermentation liquid sedimentation slurry from wineries, sedimentation slurry from vinegar plants, fermentation slurry from beer, juice and beverage plants, expired liquid milk and latex sludge from dairy plants, and concentrated liquid from the kitchen waste disposal industry.

3. The preparation method according to claim 1, characterized in that, In step (2), the compound microbial agent includes lactic acid bacteria, yeast, acetic acid bacteria, formic acid bacteria, Bacillus, EM bacteria and photosynthetic bacteria; the amount of compound microbial agent and excipients added per ton of raw material is: 50g of lactic acid bacteria, 150g of yeast, 55g of acetic acid bacteria, 30g of formic acid bacteria, 200g of a mixture of Bacillus and EM bacteria, 50g of sodium chloride, and 500-1000g of molasses. The amount of photosynthetic bacteria added is flexibly adjusted according to the seasonal temperature: reduce or not add when the temperature is high in summer, and add 30-50g per ton of raw material when the temperature is low in winter.

4. The preparation method according to claim 1, characterized in that, In step (4), the fermentation process is as follows: the fermentation temperature is controlled at 30-45℃, the fermentation time is 48-70 hours, and the stirring is turned on for 10 minutes every 12 hours.

5. A processing apparatus for implementing the preparation method according to any one of claims 1 to 4, characterized in that, Including those connected sequentially: Raw material tank (1) is used to store one or more industrial organic waste liquid raw materials; Fermentation filter tank (2), whose inlet is connected to the outlet of the raw material tank, the fermentation filter tank (2) is equipped with a stirrer (2.1) driven by a stirring motor (2.3), a bacteria inlet (2.2) and a temperature control device, for the fermentation reaction of raw materials and compound microbial agents; A solid-liquid separation device, the inlet of which is connected to the outlet of the fermentation filter tank, is used to separate the solid and liquid components of the mixture after fermentation. The dispensing tank (4) has its inlet connected to the liquid outlet of the solid-liquid separation equipment and is used to temporarily store the supernatant after filtration. The compounding tank (5) has its inlet connected to the outlet of the dispensing tank. The compounding tank (5) is equipped with a stirrer driven by a stirring motor (5.3). The compounding tank (5) is also equipped with an additive inlet. The additive inlet (5.4) is connected to the molasses dilution tank (5.6) and other additive tanks (5.7) respectively, for secondary compounding of the supernatant. The finished product tank (6) has its inlet connected to the outlet of the compounding tank and is used to store the final finished product.

6. The processing apparatus according to claim 5, characterized in that, The solid-liquid separation equipment is a plate and frame filter press (3). The plate and frame filter press (3) has a compressed air inlet (3.1) at the top and a filter residue outlet (3.2) and a supernatant outlet (3.3) at the bottom.

7. The processing apparatus according to claim 5, characterized in that, The fermentation filter tank (2) is equipped with a heating and insulation jacket (2.4); the agitator is a mechanical agitator or a bottom aeration agitator; and the temperature control device includes a heater, a cooling coil and a temperature sensor.

8. The processing apparatus according to claim 5, characterized in that, The raw material tank includes multiple independent raw material tanks, which are used to store different types of industrial organic waste liquid raw materials. Each raw material tank is equipped with a BOD / COD / PH detection port (1.2), and each raw material tank is connected to the fermentation filter tank (2) through a raw material pump (1.3) and a pipeline (1.4).

9. The processing apparatus according to claim 5, characterized in that, The compounding tank (5) is equipped with an online COD detector (5.1); the compounding tank (5) is connected to the finished product tank (6) via a transfer pump (5.5).

10. A nutrient solution prepared by the preparation method according to any one of claims 1 to 4.

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