Method for synergistically converting multi-source organic waste into sewage treatment composite carbon source and application

Abstract

The invention discloses a method for synergistically converting multi-source organic waste into a sewage treatment composite carbon source and application of the method. The method comprises the following steps: S1, firstly, adding a kitchen waste three-phase centrifuge liquid phase, pericarpium citri reticulatae waste pulp squeezed juice, alcohol byproducts of biodiesel prepared from kitchen waste oil and polysaccharide byproducts of an alcohol extraction process of a traditional Chinese medicine factory into a reaction kettle; adding the raw materials into a stirring tank according to a certain proportion and fully stirring; s2, carrying out sterilization treatment on the uniformly mixed mixed solution, and sterilizing the mixed solution by adopting a high-temperature instantaneous sterilization mode to obtain a composite carbon source finished product after sterilization is completed; s3, finally, the obtained composite carbon source finished product is sealed and stored under the normal-temperature condition. According to the invention, various organic wastes are reasonably treated and compounded to be converted into the composite carbon source, so that nutrient substances required by denitrification microorganisms for sewage treatment are balanced, the denitrification efficiency can be improved, and resource recycling and reutilization of the organic wastes are also realized, so that the urgent requirements of the sewage treatment industry on high-efficiency and low-cost carbon sources are met.

Description

Technical Field

[0001] This application relates to the technical field of multi-source organic waste treatment, and in particular to a method and application for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment. Background Art

[0002] At present, with the increasingly strict environmental protection requirements, the high efficiency of the denitrification process in sewage treatment has become increasingly important. When denitrifying microorganisms carry out denitrification, they require sufficient and balanced nutrients, and carbon source is one of the key factors. A suitable carbon source can provide sufficient nutrients for denitrifying microorganisms, promote their growth and metabolism, and thus effectively improve the denitrification efficiency. However, traditional externally added carbon sources such as methanol, sodium acetate, glucose, etc. have relatively high costs, and a single carbon source is difficult to meet the comprehensive requirements of denitrifying microorganisms for various nutrients. At the same time, a large amount of organic waste, such as the three-phase centrifugal waste liquid generated in the aerobic composting process of kitchen waste, the waste pulp generated in the production and processing of tangerine peel, the by-products of biodiesel production, and the polysaccharide by-products generated in the production and processing of traditional Chinese medicine, if not effectively utilized, will not only cause waste of resources, but also bring environmental pollution problems. If these organic wastes can be converted into a composite carbon source for sewage treatment, it can not only solve environmental problems, but also reduce the cost of sewage treatment, with significant economic and environmental benefits.

[0003] In terms of organic waste treatment, there are many deficiencies in the treatment methods of current organic wastes such as kitchen waste, tangerine peel waste pulp, alcohol by-products of biodiesel production from kitchen waste oil, and polysaccharide by-products of the alcohol extraction process in traditional Chinese medicine factories. For the three-phase centrifugal waste liquid generated in the aerobic composting process of kitchen waste, directly purifying it as high-concentration organic wastewater has a complex sewage treatment process, high project cost, and high operating cost, seriously affecting the profitability of the kitchen waste treatment project. Most of the tangerine peel waste pulp is directly discarded, causing waste of resources, and at the same time, it may cause odor and environmental pollution problems when decomposing in the natural environment. Due to the large number of impurities in crude glycerol, its subsequent utilization is restricted, and generally, it needs to go through a complex and costly refining process to be used in other industrial fields. The polysaccharide by-products of traditional Chinese medicine alcohol extraction are usually treated as waste and not effectively utilized, and the rich nutrients contained in them are wasted in vain.

[0004] Therefore, in view of the problems existing in the application of the above traditional carbon sources and the treatment of organic waste, it is of great practical significance to urgently develop a method that can not only effectively utilize organic waste but also provide high-quality composite carbon sources for sewage treatment denitrification. Summary of the Invention

[0005] The purpose of this application is to provide a method and application for co - converting composite carbon sources for sewage treatment from multiple sources of organic waste, so as to solve the problems existing in the application of traditional carbon sources and the treatment of organic waste. Thus, it can convert multiple organic wastes into composite carbon sources, realizing the resource utilization of organic waste, reducing the cost of sewage treatment, and improving the denitrification efficiency. Furthermore, it can meet the urgent needs of the sewage treatment industry for high - efficiency and low - cost carbon sources.

[0006] On the one hand, the method for co - converting composite carbon sources for sewage treatment from multiple sources of organic waste provided by this application adopts the following technical solutions: The method for co - converting composite carbon sources for sewage treatment from multiple sources of organic waste includes a raw material pretreatment process and a composite carbon source preparation process; The raw material pretreatment process includes the following steps: S1. Obtaining the liquid phase of the three - phase centrifuge of food waste: The food waste transported into the site is sorted and impurities are removed to remove large impurities. Then the food waste is pulped to be broken into uniform slurry. Next, the slurry is steamed to fully ripen the material and fully separate the animal and vegetable oils and fats in the material. Then, inorganic impurities such as sand grains are removed through a sand removal process. Then, the oil is separated through the oil extraction process of the three - phase centrifuge, and the liquid phase of the three - phase centrifuge is obtained; S2. Obtaining the squeezed juice of tangerine peel waste pulp: The waste pulp is obtained from a tangerine peel production processing factory, and the juice is obtained through a pressing process; S3. Obtaining the alcohol by - product of biodiesel production from waste cooking oil: This by - product has a short carbon chain and high purity and is a good carbon source for microorganisms. The method of vacuum distillation is used to remove the moisture and a small amount of residual fatty acid methyl esters and other impurities in it, and finally it is used as a raw material for compounding the composite carbon source after treatment; S4. Obtaining the polysaccharide by - product of the alcohol extraction process in traditional Chinese medicine factories: The main component of this by - product is polysaccharide substances, which are directly used as raw materials for compounding the composite carbon source; The composite carbon source preparation process includes the following steps: S1. First, the liquid phase of the three - phase centrifuge of food waste, the squeezed juice of tangerine peel waste pulp, the alcohol by - product of biodiesel production from waste cooking oil, and the polysaccharide by - product of the alcohol extraction process in traditional Chinese medicine factories after the above pretreatment are added to a stirring tank in a certain proportion, and are fully stirred and mixed evenly; S2. Then, the mixed solution after mixing is sterilized. The high - temperature short - time sterilization method is used to sterilize the mixed solution, and the finished product of the composite carbon source is obtained after sterilization; S3. Finally, the obtained finished product of the composite carbon source is sealed and stored at room temperature.

[0007] Further, during the process of obtaining the liquid phase of the three-phase centrifuge for kitchen waste, acid-producing microorganisms that have been pre-enriched and domesticated are added to the liquid phase produced by the three-phase centrifuge. Anaerobic fermentation hydrolysis is used to produce organic acids and organic alcohols; then continuous anaerobic fermentation is carried out for 5 to 7 days, and the hydrolyzed liquid after anaerobic fermentation is filtered through a microfiltration membrane to remove residual fine solid impurities therein.

[0008] Further, the proportion of the acid-producing microorganisms is 15% - 30%, and the pore size of the microfiltration membrane is 0.3 - 0.8 μm.

[0009] Further, during the anaerobic fermentation process, the fermentation temperature is controlled between 25 and 35 °C; at the same time, during the entire anaerobic fermentation process, regular stirring is required, stirring 4 times a day, continuously stirring for 30 minutes each time, and the stirring rate is controlled at 30 - 45 r / min.

[0010] Further, during the process of obtaining the squeezed juice from tangerine peel waste pulp, after squeezing the waste pulp from the tangerine peel production factory to obtain the juice, pectinase with a mass fraction of 0.1% - 0.3% and a purity of 99.5% is added, and then enzymatic hydrolysis is carried out at 35 - 40 °C for 2 - 3 h. Finally, centrifugation is carried out at a rotational speed of 3000 r / min for 30 minutes to remove sediment impurities, and the supernatant is collected.

[0011] Further, during the process of obtaining the alcohol by-products in the production of biodiesel from kitchen waste oil, the distillation temperature is controlled at 120 - 150 °C and the distillation pressure is controlled at 1 - 5 kPa.

[0012] Further, the liquid phase of the three-phase centrifuge for kitchen waste, the squeezed juice from tangerine peel waste pulp, the alcohol by-products in the production of biodiesel from kitchen waste oil, and the polysaccharide by-products of the alcohol extraction process in traditional Chinese medicine factories are added to a stirring tank in a volume ratio of (3 - 5):(1 - 2):(1 - 3):(1 - 2) respectively for sufficient stirring.

[0013] Further, the stirring speed of the stirrer in the stirring tank is 15 - 30 r / min, and the stirring time is 30 minutes.

[0014] Further, when using the method of high-temperature short-time sterilization, the sterilization temperature is 135 °C and the sterilization time is 5 seconds; at the same time, the obtained finished product of the composite carbon source is sealed and stored at room temperature of 20 - 30 °C, and it can be stably stored for more than 6 months, and the fluctuation range of the technical indicators of the finished product of the composite carbon source during storage does not exceed ±5%.

[0015] On the other hand, the application of the composite carbon source for sewage treatment by multi-source organic waste collaborative conversion provided by this application adopts the following technical scheme: The application of a composite carbon source for sewage treatment through the co - conversion of multi - source organic wastes. The finished product of the composite carbon source prepared by the above - mentioned method is applied to nitrogen removal in sewage treatment.

[0016] Compared with the prior art, the beneficial effects of this application are as follows: This application rationally processes and compound - converts a variety of organic wastes into a composite carbon source, balancing the nutrients required by microorganisms for nitrogen removal in sewage treatment. Thus, it can reduce the cost of sewage treatment and improve the nitrogen removal efficiency. At the same time, it realizes the resource recovery and reuse of organic wastes, thereby reducing the production cost of the composite carbon source, and further meeting the urgent needs of the sewage treatment industry for high - efficiency and low - cost carbon sources. Specific Embodiments

[0017] The following further elaborates on this application.

[0018] On the one hand, the embodiment of this application discloses a method for the co - conversion of multi - source organic wastes into a composite carbon source for sewage treatment, adopting the following technical solution: Specifically, in this embodiment, the method includes a raw material pretreatment process and a composite carbon source preparation process.

[0019] Among them, the raw material pretreatment process includes the following steps: S1. Obtaining the liquid phase of the kitchen waste three - phase centrifuge: The kitchen waste transported into the site is sorted and impurities removed, removing large - sized impurities such as plastics and metals. Then the sorted and impurity - removed kitchen waste is pulped to break it into a uniform slurry, specifically, the particle size of the slurry is 1 - 3 mm.

[0020] Then, steam at 0.6 MPa and 170 °C is used to uniformly heat the slurry to 70 - 80 °C for cooking, and the cooking time is 30 min to fully ripen the material, so as to fully separate out the animal and vegetable oils and fats in the material. Then, inorganic impurities such as sand grains are removed through a sand - removal process. Then, the oil is separated through the oil - extraction process of the three - phase centrifuge to obtain the liquid phase of the three - phase centrifuge. This liquid phase is rich in various organic substances such as short - chain fatty acids and carbohydrates, providing a carbon source and part of the nitrogen source for microorganisms.

[0021] In addition, during the process of obtaining the liquid phase of the three-phase centrifuge for kitchen waste, acidogenic microorganisms that have been pre-enriched and domesticated are added to the liquid phase produced by the above-mentioned three-phase centrifuge. Specifically, the proportion of the added acidogenic microorganisms is 15%-30%. And anaerobic fermentation is used to hydrolyze and produce organic acids and organic alcohols; preferably, during the anaerobic fermentation process, the fermentation temperature is controlled between 25-35°C; at the same time, during the entire anaerobic fermentation process, regular stirring is required, stirring 4 times a day, continuously stirring for 30 minutes each time, and the stirring rate is controlled at 30-45 r / min, so as to ensure close contact between the acidogenic microorganisms and the liquid phase of the three-phase centrifuge for kitchen waste.

[0022] Then, continuous anaerobic fermentation is carried out for 5-7 days, and the hydrolyzate after anaerobic fermentation is filtered using a microfiltration membrane to remove the remaining fine solid impurities therein; more preferably, the pore size of the microfiltration membrane is 0.3-0.8 μm, which can achieve a better filtration effect on the hydrolyzate.

[0023] The following Table 2-1 shows the technical indicators of the liquid phase of the three-phase centrifuge for kitchen waste.

[0024] S2. Obtaining the squeezed juice of orange peel waste pulp: Obtain waste pulp from an orange peel production processing factory and get the juice through a squeezing process. This juice contains rich organic acids, sugars, flavonoid compounds, etc., which can not only provide a carbon source but also have certain biological activities, helping the growth and metabolism of microorganisms.

[0025] At the same time, during the process of obtaining the squeezed juice of orange peel waste pulp, after squeezing the waste pulp juice of the orange peel production processing factory, add pectinase with a mass fraction of 0.1%-0.3%, and the purity of the pectinase is 99.5%, then enzymatically hydrolyze at 35-40°C for 2-3 hours, and finally centrifuge at 3000 r / min for 30 minutes to remove the precipitated impurities and collect the supernatant.

[0026] The following Table 2-2 shows the squeezed juice of orange peel waste pulp.

[0027] S3. Obtaining the alcohol by-products of biodiesel produced from kitchen waste oil: This by-product has a short carbon chain and high purity, and is a good carbon source for microorganisms. Using the method of vacuum distillation, remove the water and a small amount of residual fatty acid methyl esters and other impurities therein, and finally, after treatment, it can be used as a raw material for compound carbon source compounding. Specifically, during the process of obtaining the alcohol by-products of biodiesel produced from kitchen waste oil, control the distillation temperature at 120-150°C and the distillation pressure at 1-5 kPa.

[0028] The following Table 2-3 shows the alcohol by-products of biodiesel produced from kitchen waste oil.

[0029] S4. Obtaining the polysaccharide by - product of the alcohol extraction process in traditional Chinese medicine factories: This by - product is obtained from various traditional Chinese medicines through the alcohol extraction process in traditional Chinese medicine factories, and the main component of this by - product is polysaccharide substances, which can be directly used as the compound carbon source compounding raw materials.

[0030] The following Table 2 - 4 shows the polysaccharide by - products of the alcohol extraction process in traditional Chinese medicine factories.

[0031] Therefore, through the above - mentioned pretreatment process steps such as filtration and hydrolysis acid production of the liquid phase of the three - phase centrifuge, enzymatic hydrolysis and centrifugation of the pressed juice from waste pulp in tangerine peel production and processing plants, distillation and purification of the alcohol by - product in the production of biodiesel from kitchen waste oil, and their corresponding parameter ranges, the specific combination of these pretreatment process steps and parameters is the key link to ensure that the raw materials are suitable for subsequent processing and finally form high - quality compound carbon sources.

[0032] In addition, in this embodiment, the preparation process of the compound carbon source includes the following steps: S1. First, add the above - mentioned pretreated liquid phase of the three - phase centrifuge of kitchen waste, pressed juice from waste pulp of tangerine peel, alcohol by - product in the production of biodiesel from kitchen waste oil, and polysaccharide by - product of the alcohol extraction process in traditional Chinese medicine factories into a stirring tank in a certain proportion, and carry out sufficient stirring to mix evenly.

[0033] Specifically, add the liquid phase of the three - phase centrifuge of kitchen waste, pressed juice from waste pulp of tangerine peel, alcohol by - product in the production of biodiesel from kitchen waste oil, and polysaccharide by - product of the alcohol extraction process in traditional Chinese medicine factories into the stirring tank according to the volume ratio of (3 - 5):(1 - 2):(1 - 3):(1 - 2) respectively for sufficient stirring. And a stirrer is installed in the stirring tank, the stirring speed of the stirrer is 15 - 30 r / min, and the stirring time is 30 min.

[0034] In this way, by setting the combination method of the liquid phase of the three - phase centrifuge of kitchen waste after sorting, impurity removal, pulping, cooking, sand removal, and oil extraction, the pressed juice from waste pulp in tangerine peel production and processing plants, the alcohol by - product in the production of biodiesel from kitchen waste oil, and the polysaccharide by - product generated by the alcohol extraction process in traditional Chinese medicine production and processing plants, using this unique raw material combination is the material basis for the preparation of the compound carbon source in the present invention, which can be distinguished from other methods of using single or different combinations of organic waste to prepare carbon sources. At the same time, through the above - mentioned precise compounding ratio and mixing process, the balance of nutrients in the compound carbon source is ensured, which is an important technical feature for improving the denitrification efficiency in the present invention.

[0035] S2. Then, sterilize the mixed liquid after mixing. Sterilize the mixed liquid by means of high-temperature instantaneous sterilization. After the sterilization is completed, the finished product of the composite carbon source is obtained. Specifically, when using the high-temperature instantaneous sterilization method, the sterilization temperature is 135°C and the sterilization time is 5 seconds.

[0036] S3. Finally, store the obtained finished product of the composite carbon source sealed at room temperature; specifically, store the obtained finished product of the composite carbon source sealed at room temperature of 20°C - 30°C, which can be stably stored for more than 6 months, and the fluctuation range of each technical index of the finished product of the composite carbon source during storage does not exceed ±5%.

[0037] The following Table 2-5 is the finished product of the composite carbon source.

[0038] Therefore, through the above description: The present invention makes full use of a variety of organic wastes, realizes the effective recovery and reuse of resources, and reduces the production cost of the composite carbon source. At the same time, through the reasonable compounding of different organic wastes, the composite carbon source contains rich carbon and other nutrient elements, as well as trace elements and growth factors required for the growth of various microorganisms, so as to be able to evenly meet the nutritional needs of sewage treatment denitrifying microorganisms and significantly improve the denitrification efficiency. In addition, through the synergistic effect of each step, the resource utilization of organic wastes and the preparation of high-efficiency composite carbon source are realized, which is different from other similar preparation methods.

[0039] In addition, through experimental verification, compared with traditional carbon sources, when using the composite carbon source prepared by the present invention, the denitrification efficiency in the sewage treatment system can be increased by 8% - 15%; and the composite carbon source product prepared by the present invention has stable properties, is easy to store and transport, and has broad application prospects in the field of sewage treatment.

[0040] On the other hand, the application of the composite carbon source for sewage treatment by the synergistic conversion of multi-source organic wastes provided by the present application adopts the following technical solutions: Specifically, in the application of the composite carbon source for sewage treatment by the synergistic conversion of multi-source organic wastes, the finished product of the composite carbon source prepared by the above method is applied to sewage treatment denitrification.

[0041] More specifically, the following is the production application test of the prepared finished product of the composite carbon source: Example 1: Application test of a certain street town urban sewage treatment plant in Foshan City, Guangdong Province.

[0042] Basic information of the sewage treatment plant: The urban sewage treatment plant in this street town adopts the A² / O process, and the average daily urban domestic sewage treatment volume is about 18,000 m³ / d. Inlet water quality: total nitrogen 45 mg / L, COD 120 mg / L, and the original effluent total nitrogen standard design is 12 mg / L.

[0043] Test process: Conduct a 30-day continuous operation test. Divide the sewage treatment system into two groups. One group is dosed with the composite carbon source prepared by the present invention, and the other group is dosed with traditional sodium acetate as the carbon source. During the entire test period, except for the different types of carbon sources, other treatment process parameters, including aeration volume, hydraulic retention time, sludge return ratio, etc., are kept consistent to ensure the accuracy and comparability of the test results.

[0044] Test results: In the system using the composite carbon source of the present invention, during the 30-day test cycle, the average total nitrogen concentration in the effluent was detected to be 10 mg / L. According to the denitrification efficiency calculation formula: Denitrification efficiency = (Inlet total nitrogen concentration - Effluent total nitrogen concentration) ÷ Inlet total nitrogen concentration × 100%, the calculated denitrification efficiency is (45 - 10) ÷ 45 × 100% ≈ 77.8%.

[0045] In the system using sodium acetate as the carbon source, the average total nitrogen concentration in the effluent was 13 mg / L. Calculated according to the same formula, its denitrification efficiency is (45 - 13) ÷ 45 × 100% ≈ 71.1%.

[0046] Through this actual application test in a certain street town's urban sewage treatment plant in Foshan City, Guangdong Province, it clearly and intuitively shows that the composite carbon source of the present invention has a significant improvement in denitrification efficiency compared with the traditional sodium acetate carbon source. Using the composite carbon source of the present invention can further reduce the total nitrogen concentration of the treated sewage, which is more conducive to meeting the increasingly stringent environmental protection discharge standards, and provides a more efficient and advantageous solution for the selection of carbon sources in urban sewage treatment processes.

[0047] Example 2: Production application test in an industrial wastewater treatment plant in Foshan City, Guangdong Province.

[0048] Basic information of the sewage treatment plant: This industrial wastewater treatment plant uses the A² / O process to treat industrial wastewater, with a daily average industrial wastewater treatment volume of about 8000 m³ / d. Inlet water quality: pH value 7.5, COD 78 mg / L, total nitrogen 41.42 mg / L, ammonia nitrogen 17 mg / L, total phosphorus 0.5 mg / L, and the original effluent total nitrogen standard is designed to be 12 mg / L.

[0049] Test process: Conduct a 30-day operation test. Divide the wastewater treatment system into two groups. One group is dosed with the composite carbon source prepared by the present invention, and the other group is dosed with traditional sodium acetate carbon source. During the test period, except for the different types of carbon sources, the remaining treatment process parameters, such as aeration time, hydraulic retention time of the anaerobic tank and aerobic tank, sludge return ratio, etc., are maintained unchanged to ensure the accuracy and reliability of the test results.

[0050] Test results: In the system using the composite carbon source of the present invention, during the 30-day test cycle, after multiple detections, the average total nitrogen concentration in the effluent was 9 mg / L. According to the denitrification efficiency calculation formula: Denitrification efficiency = (Inlet total nitrogen concentration - Effluent total nitrogen concentration) ÷ Inlet total nitrogen concentration × 100%, the calculated denitrification efficiency was (41.42 - 9) ÷ 41.42 × 100% ≈ 78.7%.

[0051] For the system using sodium acetate as the carbon source, the average total nitrogen concentration in the effluent was 13 mg / L. Calculated according to the same formula, its denitrification efficiency was (41.42 - 13) ÷ 41.42 × 100% ≈ 68.6%.

[0052] The actual application test in an industrial wastewater treatment plant in Foshan City, Guangdong Province this time shows that compared with the traditional sodium acetate carbon source, the composite carbon source of the present invention exhibits higher efficiency in the denitrification treatment of industrial wastewater. Using the composite carbon source of the present invention can make the total nitrogen concentration in the treated industrial wastewater closer to or even better than the design standard, which strongly proves the applicability and superiority of this composite carbon source in the field of industrial wastewater treatment and provides a practical new option for the optimization of industrial wastewater treatment processes.

[0053] The above are only embodiments of the present invention and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made using the content of the specification of the present invention, or directly or indirectly applied in other related technical fields, shall be included in the patent protection scope of the present invention by the same token.

Claims

1. A method for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment, characterized in that: It includes a raw material pretreatment process and a composite carbon source preparation process; The raw material pretreatment process comprises the following steps: S1. Obtaining the liquid phase of the three-phase centrifuge of restaurant kitchen waste: The restaurant kitchen waste collected and transported to the site is sorted and impurities are removed to remove large impurities; then the restaurant kitchen waste is pulped to be broken into a uniform slurry; then the slurry is steamed to fully mature the material to fully extract the animal and plant oils in the material; then the sand removal process is used to remove inorganic impurities such as sand particles; then the oil is separated through the three-phase centrifuge oil extraction process to obtain the three-phase centrifuge liquid phase; S2. Obtaining juice by squeezing waste tangerine peel pulp: Obtain waste tangerine peel pulp from a tangerine peel production and processing plant, and obtain juice by squeezing; S3. Obtaining alcohol byproducts from the production of biodiesel from waste cooking oil: This byproduct has a short carbon chain and high purity, and is a good carbon source for microorganisms. The water and a small amount of residual impurities such as fatty acid methyl ester are removed by vacuum distillation, and finally used for composite carbon source compounding raw materials after treatment; S4. Acquisition of polysaccharide byproducts from the alcohol extraction process of traditional Chinese medicine factories: The main component of the byproduct is polysaccharide substances, which are directly used as composite carbon source compound raw materials; The composite carbon source preparation process comprises the following steps: S1, firstly, the pre-treated three-phase centrifuge liquid phase of the kitchen waste, the squeezed juice of the tangerine peel waste pulp, the alcohol by-products of biodiesel produced from kitchen waste oil, and the polysaccharide by-products of the alcohol extraction process of the traditional Chinese medicine factory are added into a stirring tank according to a certain proportion, and fully stirred and mixed evenly; S2, and then sterilizing the mixed solution by high-temperature instantaneous sterilization. After the sterilization is completed, the finished composite carbon source is obtained; S3. Finally, the obtained composite carbon source product is sealed and stored at room temperature.

2. The method of claim 1 for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment, characterized in that: In the process of obtaining the liquid phase of the three-phase centrifuge of food waste, the acid-producing microorganisms that have been enriched and domesticated in advance are added to the liquid phase obtained from the three-phase centrifuge, and anaerobic fermentation is used for hydrolysis to produce organic acids and organic alcohols; then continuous anaerobic fermentation is carried out for 5d-7d, and the hydrolyzate after anaerobic fermentation is filtered with a microfiltration membrane to remove the fine solid impurities remaining therein.

3. The method of synergistically converting multi-source organic waste into a composite carbon source for sewage treatment according to claim 2, characterized in that: The proportion of the acid-producing microorganisms is 15%-30%, and the pore size of the microfiltration membrane is 0.3um-0.8um.

4. The method of claim 2 for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment, characterized in that: During the anaerobic fermentation process, the fermentation temperature is controlled between 25-35°C; at the same time, regular stirring is required throughout the anaerobic fermentation process, stirring 4 times a day, each time for 30 minutes, and the stirring rate is controlled at 30-45r / min.

5. The method of claim 1 for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment, characterized in that: In the process of obtaining juice from the waste pulp of tangerine peel, the waste pulp from the tangerine peel production and processing plant is squeezed into juice, and then 0.1%-0.3% pectinase by mass is added, and the purity of the pectinase is 99.5%, and then enzymolysis is carried out at 35-40°C for 2-3h, and finally centrifuged at 3000r / min for 30min to remove precipitated impurities and collect the supernatant.

6. The method of claim 1 for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment, characterized in that: In the process of obtaining alcohol by-products from cooking waste oil to biodiesel, the distillation temperature is controlled at 120-150°C and the distillation pressure is controlled at 1-5kPa.

7. The method of claim 1 for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment, characterized in that: The liquid phase of the three-phase centrifuge of food waste, the juice squeezed from the waste pulp of tangerine peel, the alcohol by-products of biodiesel produced from food waste oil, and the polysaccharide by-products of the alcohol extraction process of the traditional Chinese medicine factory were added into a mixing tank in a volume ratio of (3-5): (1-2): (1-3): (1-2) and fully stirred.

8. The method of claim 7 for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment, characterized in that: The stirring speed of the stirrer in the stirring tank is 15-30 r / min, and the stirring time is 30 min.

9. The method of claim 1 for synergistically converting multi-source organic waste into a composite carbon source for sewage treatment, characterized in that: When high-temperature instantaneous sterilization is adopted, the sterilization temperature is 135°C and the sterilization time is 5 seconds; at the same time, the obtained composite carbon source finished product is sealed and stored at room temperature of 20°C-30°C, and can be stably stored for more than 6 months, and the fluctuation range of various technical indicators of the composite carbon source finished product during the storage period does not exceed ±5%.

10. Application of multi-source organic wastes in synergistic conversion of composite carbon sources for sewage treatment, the method for synergistic conversion of multi-source organic wastes in synergistic conversion of composite carbon sources for sewage treatment according to any one of claims 1 to 9, characterized in that: The finished composite carbon source prepared by the above method is used in sewage treatment and denitrification.

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