Equipment for preparing carbon source from kitchen waste biogas slurry and treatment method thereof
By setting an intermediate heating network and a condensation table in the anaerobic fermentation tank, the problem of condensation and reflux of water vapor and ammonia is solved, and the efficiency of carbon source preparation is improved.
Patent Information
- Application Number
- CN202510993128.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-18
- Publication Date
- 2025-09-12
AI Technical Summary
In the prior art, water vapor generated in the anaerobic fermentation tank condenses and refluxes, and ammonia dissolves in water, resulting in prolonged hydrothermal treatment time and low carbon source preparation efficiency.
A fully automatic anaerobic fermentation tank and a top collection tank are used, with an intermediate heating network and a top wall heating network. A condensing table is used to condense water vapor and collect it in a collection pool. Ammonia is dissolved in the water in the collection pool and discharged through a drain pipe to avoid backflow into the reaction solution.
The reaction speed is accelerated, the efficiency of carbon source preparation is improved, and the time extension caused by condensed water backflow and ammonia dissolution is avoided.
Smart Images
Figure CN120624181A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of separation equipment, and in particular to an equipment for preparing carbon sources from kitchen waste biogas slurry and a processing method thereof. Background Art
[0002] Anaerobic fermentation can achieve the degradation and resource utilization of organic matter in food waste, and is also a commonly used technology for converting food waste into energy. The anaerobic fermentation liquid of food waste contains rich nutrients, including C sources (such as VFAs and alcohols) and N sources (such as NH4 + ), can provide nutrients for plant and microbial growth, such as essential carbon and nitrogen sources for soil growth, enhancing soil fertility. However, the high salinity and low pH of anaerobic fermentation broth, as well as heavy metals and other harmful substances, can lead to soil salinization and acidification. Direct irrigation of the fermentation broth can make it difficult to control the effective dosage and application rate of external carbon and nitrogen sources. Therefore, safe methods for effectively separating and utilizing anaerobic fermentation broth from food waste are attracting increasing attention.
[0003] During hydrothermal treatment in the anaerobic fermenter, a certain amount of water vapor is generated due to the slurry temperature reaching 70°C. The hydrothermal treatment lasts for 24 hours, resulting in a large amount of water vapor in the fermenter. This water vapor condenses upon cooling, then drips back into the solution. Simultaneously, ammonia is generated during the reaction in the fermenter. Ammonia is highly soluble in water, meaning that the generated ammonia dissolves in the condensed water and then decomposes again after returning to the solution. This results in a portion of ammonia always being dissolved in the water and unable to be discharged, resulting in a longer hydrothermal treatment time and lower overall carbon source preparation efficiency. Summary of the Invention
[0004] The present application provides an apparatus for preparing a carbon source from kitchen waste biogas and a treatment method thereof, thereby solving the technical problem in the prior art that a large amount of water vapor is generated in the fermentation tank, the water vapor condenses after being cooled, and then drips again and flows back into the solution. Ammonia gas is generated in the reaction in the fermentation tank, and ammonia gas is highly soluble in water. That is to say, the generated ammonia gas will dissolve in the condensed water, and then decompose again after flowing back into the solution, resulting in a part of the ammonia gas always dissolving in the water and unable to be discharged, resulting in a long hydrothermal treatment time and low overall carbon source preparation efficiency. The application achieves the technical effect of accelerating the reaction speed and improving the carbon source preparation efficiency.
[0005] The present application provides a device for preparing a carbon source from kitchen waste biogas, comprising a fully automatic anaerobic fermentation tank and a top collection tank, wherein the top collection tank comprises: A second tank body, the second tank body is used to receive the N2 blown out of the fully automatic anaerobic fermentation tank and the NH3 generated by the reaction; an intermediate heating net, wherein the intermediate heating nets are provided in plurality and are arranged in an upper and lower interval in the inner cavity of the second tank body, and the intermediate heating nets are used to heat the inner cavity of the second tank body to prevent condensation of water vapor in the inner cavity of the second tank body; A condensation table is provided on the top of the second tank body. The condensation table is in the shape of an inverted cone. A condenser is provided inside the condensation table. The condenser is used to reduce the temperature of the condensation table. The water vapor generated by the reaction condenses on the condensation table and gradually gathers at the pointed cone of the condensation table. A collecting tank, the collecting tank being located directly below the pointed cone of the condensation table and being used to collect water dripping from the pointed cone of the condensation table; a drain pipe, wherein the starting end of the drain pipe is connected to the bottom of the collection tank, and the terminal end of the drain pipe extends out of the second tank body; An air outlet is provided at the top of the second tank body, and is used to discharge N2 and NH3 in the second tank body.
[0006] Furthermore, the fully-automatic anaerobic fermentation tank is used to contain biogas slurry, which reacts in the fully-automatic anaerobic fermentation tank. The fully-automatic anaerobic fermentation tank includes a first tank body, which is used to contain biogas slurry. The first tank body is located below the second tank body, and the inner cavity of the first tank body is connected to the inner cavity of the second tank body. A top wall heating net is provided on the top of the inner wall of the first tank body, and the top wall heating net is used to heat the top of the inner wall of the first tank body to prevent water vapor from condensing on the top of the inner wall of the first tank body.
[0007] Furthermore, the fully automatic anaerobic fermentation tank also includes: a stirrer, the stirrer being disposed in the first tank and being used to stir the biogas slurry to facilitate its reaction; A discharge port is provided at the bottom of the first tank body and is used to discharge the product remaining after the biogas slurry reaction; a water inlet, the water inlet being provided at the bottom of the first tank body and being used for adding water into the first tank body; A feed inlet is provided at the top of the first tank body and is used to add biogas slurry into the first tank body.
[0008] Furthermore, the fully automatic anaerobic fermentation tank also includes: An N2 inlet is provided at the top of the first tank body and is connected to the nitrogen-air integrated machine. The N2 inlet is used to add biogas slurry N2 into the first tank body to maintain an N2 atmosphere during the reaction. The N2 inlet is connected to an N2 conduit leading to the bottom of the first tank body and is used to extend into the biogas slurry during the reaction to blow off NH3 generated during the reaction; A water bath heating jacket is provided surrounding the first tank body and is used for heating the first tank body to perform hydrothermal treatment on the biogas slurry.
[0009] Furthermore, the fully automatic anaerobic fermentation tank also includes: a monitoring mechanism, the monitoring mechanism being arranged on the side wall of the first tank body, the monitoring end of the monitoring mechanism extending into the biogas slurry, and the monitoring mechanism being used to detect the pH value and temperature of the biogas slurry; The automatic liquid adding mechanism is arranged on the top of the first tank body and is used to add reactants to the first tank body. The monitoring mechanism includes a pH monitor and a temperature sensor, and the automatic liquid adding mechanism includes an Al 3+ Solution Adder, Mg 2+ Solution feeders, lye feeders and acid feeders.
[0010] Furthermore, it also includes an ammonia recovery reaction tank, which is connected to the top collecting tank and is used to receive N2 and NH3 output from the top collecting tank; The ammonia recovery reaction tank comprises: a third tank body, wherein the third tank body is filled with water, and the drain pipe and the air outlet are both connected to the third tank body; A CO2 gas supply mechanism is used to deliver CO2 to the third tank body.
[0011] Another aspect of the present application provides a method for preparing a carbon source from kitchen waste biogas slurry, characterized by comprising the following steps: S1. Adjust the pH of the food waste biogas to 9-10; S2, stirring in N2 atmosphere, and adding Mg dropwise 2+ Solution and Al 3+ solution; S3. After the precipitate appears, the suspension is subjected to hydrothermal treatment. After the reaction is completed, the precipitate is washed and collected to obtain a carbon resource product, wherein the hydrothermal treatment is performed at 70° C. for 24 hours. The carbon resource product is an organic acid-based double metal hydroxide; S4. During the hydrothermal treatment, water vapor is condensed at the top, and part of the NH3 generated by the reaction is dissolved in the condensate, and the other part is discharged to the ammonia recovery reaction device. At the same time, the condensate is also discharged to the ammonia recovery reaction device; S5 and CO2 are introduced into the ammonia recovery reaction device to form NH4HCO3 products which are crystallized and precipitated to obtain nitrogen resource products.
[0012] Furthermore, in step S1, the kitchen waste biogas is obtained by anaerobic fermentation of kitchen waste and separation of fermentation residues; The method for anaerobic fermentation of food waste is as follows: food waste and deionized water are slurried in a mass ratio of 1:1, and then anaerobic fermentation is carried out. During the fermentation process, the temperature is controlled at 35°C, and the pH is adjusted and controlled at 5.0-6.0. Natural fermentation is carried out without inoculating sludge, and the reaction time is 3 days. When adjusting the pH of the biogas slurry, use 4M NaOH or 4M HCl to adjust the pH.
[0013] Further, in step S2, Mg 2+ The solution is Mg(NO3)2 solution, Al 3+ The solution is Al(NO3)3 solution; Mg 2+ Mg in solution 2+ ions, Al 3+ Al in solution 3+ The ratio of ions and anaerobic fermentation liquid of food waste is 0.3mol:0.15mol:5L.
[0014] The technical solution provided by this application has at least the following technical effects or advantages: 1. Due to the use of the intermediate heating network 202 and the top wall heating network 207, water vapor will not condense on the top of the first tank body 101 and the side wall of the second tank body 201 until the water vapor moves to the condensation table 203 and condenses when it is cold, forming small water droplets, which gradually gather at the pointed cone of the condensation table 203 and then drip into the collection pool 204 below. Ammonia will also dissolve in the water in the collection pool 204 and be discharged into the ammonia recovery reaction tank 3 along the drain pipe 205. Therefore, no condensed water will flow back into the reaction solution. Therefore, there is no ammonia dissolved in the condensed water and brought back into the reaction solution, thereby accelerating the reaction speed and improving the carbon source preparation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 This is a schematic diagram of the overall structure of the equipment for preparing carbon source from kitchen waste biogas slurry in an embodiment of the present application; Figure 2 This is a schematic cross-sectional view of an apparatus for preparing a carbon source from kitchen waste biogas slurry in an embodiment of the present application; Figure 3 This is a schematic structural diagram of a fully automatic anaerobic fermentation tank in an embodiment of the present application; Figure 4 This is a schematic cross-sectional view of a fully automatic anaerobic fermentation tank in an embodiment of the present application; Figure 5 This is a partial structural diagram of a fully automatic anaerobic fermentation tank in an embodiment of the present application; Figure 6 This is a schematic structural diagram of the top collecting tank in the embodiment of the present application; Figure 7 This is a schematic cross-sectional view of a top collecting tank in an embodiment of the present application; Figure 8 This is a schematic diagram of the structure of the ammonia recovery reaction tank in the embodiment of the present application.
[0016] In the figure: 1. Fully automatic anaerobic fermentation tank; 2. Top collection tank; 3. Ammonia recovery reaction tank; 101. First tank; 102. Mixer; 103. Discharge port; 104. Water inlet; 105. Feed port; 106. N2 inlet; 107. Water bath heating jacket; 108. Monitoring mechanism; 1081. pH monitor; 1082. Temperature sensor; 109. Automatic liquid addition mechanism; 1091. Al 3+ Solution adder; 1092, Mg 2+ Solution adder; 1093, alkali solution adder; 1094, acid solution adder; 201, second tank; 202, intermediate heating network; 203, condensation table; 204, collection tank; 205, drain pipe; 206, air outlet; 207, top wall heating network; 301. Third tank; 302. CO2 gas supply mechanism. DETAILED DESCRIPTION
[0017] The embodiment of the present application discloses a device for preparing a carbon source from kitchen waste biogas slurry. A top collecting tank 2 is provided to receive the N2 blown out from the fully automatic anaerobic fermentation tank 1 and the NH3 generated by the reaction, and an intermediate heating net 202 and a top wall heating net 207 are provided, so that water vapor will not condense on the top of the first tank body 101 and the side wall of the second tank body 201 until the water vapor moves to the condensation table 203 and condenses when it is cold, forming small water droplets, which gradually gather at the pointed cone of the condensation table 203 and then drip into the collection pool 204 below. Ammonia will also dissolve in the water in the collection pool 204 and be discharged into the ammonia recovery reaction tank 3 along the drain pipe 205. Therefore, no condensed water will flow back into the reaction solution. Therefore, there is no ammonia dissolved in the condensed water and brought back into the reaction solution, thereby accelerating the reaction speed and improving the carbon source preparation efficiency.
[0018] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.
[0019] Example 1, refer to Figures 1 to 8 The present application provides an apparatus for preparing a carbon source from kitchen waste biogas slurry, comprising a fully automatic anaerobic fermentation tank 1, a top collecting tank 2 and an ammonia recovery reaction tank 3. The fully automatic anaerobic fermentation tank 1 is used to contain biogas slurry, which reacts in the fully automatic anaerobic fermentation tank 1 to generate a carbon resource product. The top collecting tank 2 is connected to the fully automatic anaerobic fermentation tank 1 and is used to receive the N2 blown out of the fully automatic anaerobic fermentation tank 1 and the NH3 generated by the reaction. The ammonia recovery reaction tank 3 is connected to the top collecting tank 2 and is used to receive the N2 and NH3 output by the top collecting tank 2 and generate a nitrogen resource product.
[0020] Specifically, refer to Figure 3 and Figure 4 The fully automatic anaerobic fermentation tank 1 includes a first tank body 101, a mixer 102, a discharge port 103, a water inlet 104, a feed port 105, an N2 inlet 106, a water bath heating jacket 107, a monitoring mechanism 108, and an automatic liquid addition mechanism 109. The first tank body 101 is used to contain biogas slurry, the mixer 102 is disposed in the first tank body 101, and is used to stir the biogas slurry to facilitate its reaction, the discharge port 103 is disposed at the bottom of the first tank body 101, and is used to discharge the products remaining after the biogas slurry reaction, the water inlet 104 is disposed at the bottom of the first tank body 101, and is used to add water to the first tank body 101, and the feed port 105 is disposed at the top of the first tank body 101, and is used to add biogas slurry to the first tank body 101.
[0021] Further, refer to Figure 4 The N2 inlet 106 is provided at the top of the first tank 101 and is connected to the nitrogen-air integrated machine. The N2 inlet 106 is used to add biogas liquid N2 to the first tank 101 to maintain the N2 atmosphere during the reaction. The N2 inlet 106 is connected to an N2 conduit 1061 leading to the bottom of the first tank 101, which is used to extend into the biogas liquid during the reaction and blow off the NH3 generated during the reaction. The water bath heating jacket 107 is surrounded by the first tank. The first tank body 101 is provided with a water bath heating jacket 107 for heating the first tank body 101 to perform hydrothermal treatment on the biogas slurry. The monitoring mechanism 108 is provided on the side wall of the first tank body 101. The monitoring end of the monitoring mechanism 108 extends into the biogas slurry. The monitoring mechanism 108 is used to detect the pH value and temperature of the biogas slurry. The automatic liquid adding mechanism 109 is provided on the top of the first tank body 101. The automatic liquid adding mechanism 109 is used to add reactants to the first tank body 101. It should be noted that, referring to Figure 5 The monitoring mechanism 108 includes a pH monitor 1081 and a temperature sensor 1082, and the automatic liquid adding mechanism 109 includes an Al 3+ Solution Adder 1091, Mg 2+ Solution adder 1092 , alkali solution adder 1093 and acid solution adder 1094 .
[0022] In this embodiment, the fully automatic anaerobic fermentation tank 1 can automatically adjust pH and temperature. At the same time, it can ensure that the two external samples (Mg 2+ Solution and Al 3+ The sample solution is automatically and uniformly added dropwise, with mechanical stirring. The sample addition rate and stirring rate are adjustable. The N2 inlet 106 is connected to a nitrogen and air integrated machine to maintain an N2 atmosphere during the reaction. The N2 inlet 106 is connected to an N2 conduit 1061 at the bottom of the first tank 101. This conduit is used to extend into the anaerobic digestion slurry of the food waste during the reaction, creating an N2 atmosphere while blowing out the NH3 produced during the reaction.
[0023] When using the above-mentioned fully automatic anaerobic fermentation tank 1, first place 5.0L of anaerobic fermentation liquid of food waste that has been fermented in advance and separated by filter paper in the first tank body 101, and adjust the pH to the desired pH = 9-10 with 4M NaOH or 4M HCl, then, keep the stirring rate at 100rpm in N2 atmosphere, add 0.30molMg 2+ solution (150 mL) and 0.15 molAl 3+ The solution (150 mL) was added dropwise to the first tank 101. After precipitation occurred, the suspension was hydrothermally treated at 70°C for 24 h. After the reaction, the precipitate was washed three times with deionized water and collected by centrifugation to obtain the carbon resource product, VFA-LDH.
[0024] Further, refer to Figure 6 and Figure 7In this embodiment, the top collecting tank 2 includes a second tank body 201, an intermediate heating net 202, a condensing table 203, a collecting pool 204, a drain pipe 205, and an air outlet 206. The second tank body 201 is used to receive the N2 blown out of the fully-automatic anaerobic fermentation tank 1 and the NH3 generated by the reaction. The first tank body 101 is located below the second tank body 201, and the inner cavity of the first tank body 101 is connected to the inner cavity of the second tank body 201. A top wall heating net 207 is provided on the top of the inner wall of the first tank body 101. The top wall heating net 207 is used to heat the top of the inner wall of the first tank body 101 to prevent water vapor from condensing on the top of the inner wall of the first tank body 101. There are multiple intermediate heating nets 202, and the multiple intermediate heating nets 202 are arranged in the inner cavity of the second tank body 201 at intervals up and down. The intermediate heating net 202 is used to heat the inner cavity of the second tank body 201 to prevent water vapor from condensing in the inner cavity of the second tank body 201.
[0025] Further, refer to Figure 7 The condensation table 203 is arranged at the top of the second tank body 201. The condensation table 203 is in the shape of an inverted cone. A condenser is arranged inside the condensation table 203. The condenser is used to reduce the temperature of the condensation table 203. The water vapor generated by the reaction condenses at the condensation table 203 and gradually gathers at the tip of the condensation table 203. The collection tank 204 is located directly below the tip of the condensation table 203. The collection tank 204 is used to collect water dripping from the tip of the condensation table 203. The starting end of the drain pipe 205 is connected to the bottom of the collection tank 204, and the end of the drain pipe 205 extends out of the second tank body 2016. The air outlet 206 is arranged at the top of the second tank body 201, and the air outlet 206 is used to discharge N2 and NH3 in the second tank body 201.
[0026] The top collecting tank 2 in this embodiment receives the N2 blown out of the fully automatic anaerobic fermentation tank 1 and the NH3 generated by the reaction. At the same time, during the hydrothermal treatment of the first tank body 101, a certain amount of water vapor will be generated because the temperature of the biogas slurry reaches 70°. The hydrothermal treatment time reaches 24 hours, so that a large amount of water vapor is generated in the first tank body 101. The water vapor condenses after being cooled, and then drips again and flows back into the solution. At the same time, ammonia gas is generated in the reaction of the first tank body 101. Ammonia gas is highly soluble in water, that is, the generated ammonia gas will dissolve in the condensed water, and then decompose again after flowing back into the solution, resulting in a portion of ammonia gas always dissolving in the water and unable to be discharged, which makes the hydrothermal treatment time longer.
[0027] In this embodiment, the top collecting tank 2 is provided to accommodate the generated water vapor, and the intermediate heating network 202 and the top wall heating network 207 are provided to prevent the water vapor from condensing on the top of the first tank body 101 and the side wall of the second tank body 201 until the water vapor moves to the condensation table 203 and condenses when it is cold, forming small water droplets, which gradually gather at the pointed cone of the condensation table 203 and then drip into the collection pool 204 below. The ammonia gas will also dissolve in the water in the collection pool 204 and be discharged into the ammonia recovery reaction tank 3 along the drain pipe 205.
[0028] Through the above arrangement, no condensed water will flow back into the reaction solution. Therefore, there will be no problem of ammonia dissolved in the condensed water being brought back into the reaction solution, resulting in a part of ammonia always being dissolved in the water and unable to be discharged, making the hydrothermal treatment time longer.
[0029] Further, refer to Figure 8 The ammonia recovery reaction tank 3 of this embodiment includes a third tank body 301 and a CO2 gas supply mechanism 302. The third tank body 301 is filled with water. The liquid discharge pipe 205 and the gas outlet 206 are both connected to the third tank body 301. The CO2 gas supply mechanism 302 is used to supply CO2 to the third tank body 301. It should be noted that the CO2 gas supply mechanism 302 is a CO2 gas cylinder. In the third tank body 301, NH3 reacts with CO2NH3 to form NH4HCO3 product, which crystallizes and precipitates to obtain a nitrogen resource product.
[0030] Example 2, refer to Figures 1 to 8 The present application also provides a method for preparing a carbon source from kitchen waste biogas slurry, comprising the following steps: S1. Adjusting the pH of kitchen waste biogas to 9-10. The kitchen waste biogas is obtained by anaerobic fermentation of food waste and separation of fermentation residues. The method for anaerobic fermentation of food waste is as follows: food waste and deionized water are slurried in a mass ratio of 1:1, and then anaerobic fermentation is carried out. During the fermentation process, the temperature is controlled at 35°C, and the pH is adjusted and controlled at 5.0-6.0. Natural fermentation is carried out without inoculating sludge, and the reaction time is 3 days. When adjusting the pH of biogas slurry, use 4M NaOH or 4M HCl to adjust the pH; S2, stirring in N2 atmosphere, and adding Mg dropwise 2+ Solution and Al 3+ Solution, Mg 2+ The solution is Mg(NO3)2 solution, Al 3+ The solution is Al(NO3)3 solution; Mg 2+ Mg in solution 2+ ions, Al 3+ Al in solution3+ The ratio of ions to the amount of biogas slurry from anaerobic fermentation of food waste is 0.3 mol:0.15 mol:5 L; S3. After the precipitate appears, the suspension is subjected to hydrothermal treatment. After the reaction is completed, the precipitate is washed and collected to obtain a carbon resource product. The hydrothermal treatment refers to hydrothermal treatment at 70° C. for 24 hours. The carbon resource product is an organic acid-based double metal hydroxide. S4. During the hydrothermal treatment, water vapor is condensed at the top, and part of the NH3 generated by the reaction is dissolved in the condensate, and the other part is discharged to the ammonia recovery reaction device. At the same time, the condensate is also discharged to the ammonia recovery reaction device; S5 and CO2 are introduced into the ammonia recovery reaction device to form NH4HCO3 products which are crystallized and precipitated to obtain nitrogen resource products.
[0031] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.
[0032] The above is only a preferred specific implementation method of the embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solution and concept of the present application within the technical scope disclosed in the present application, and they should be covered by the scope of protection of the present application.
Claims
1. A device for preparing carbon source from kitchen waste biogas, characterized in that: The invention comprises a fully automatic anaerobic fermentation tank (1) and a top collecting tank (2), wherein the top collecting tank (2) comprises: A second tank body (201), the second tank body (201) is used to receive the N2 blown out of the fully automatic anaerobic fermentation tank (1) and the NH3 generated by the reaction; an intermediate heating net (202), wherein the intermediate heating net (202) comprises a plurality of intermediate heating nets (202), the plurality of intermediate heating nets (202) being arranged in an upper and lower interval in the inner cavity of the second tank body (201), and the intermediate heating net (202) being used to heat the inner cavity of the second tank body (201) to prevent condensation of water vapor in the inner cavity of the second tank body (201); A condensation table (203), the condensation table (203) is arranged on the top of the second tank (201), the condensation table (203) is in the shape of an inverted cone, a condenser is arranged inside the condensation table (203), the condenser is used to reduce the temperature of the condensation table (203), and the water vapor generated by the reaction condenses on the condensation table (203) and gradually gathers at the pointed cone of the condensation table (203); A collecting pool (204), the collecting pool (204) is located directly below the pointed cone of the condensation table (203), and the collecting pool (204) is used to collect water dripping from the pointed cone of the condensation table (203); a liquid discharge pipe (205), wherein the starting end of the liquid discharge pipe (205) is connected to the bottom of the collection tank (204), and the end of the liquid discharge pipe (205) extends out of the second tank body (201); An air outlet (206) is provided at the top of the second tank body (201), and the air outlet (206) is used to discharge N2 and NH3 in the second tank body (201).
2. The device for preparing carbon source from kitchen waste biogas slurry according to claim 1, characterized in that: The fully automatic anaerobic fermentation tank (1) is used to contain biogas slurry, and the biogas slurry reacts in the fully automatic anaerobic fermentation tank (1). The fully automatic anaerobic fermentation tank (1) comprises a first tank body (101), wherein the first tank body (101) is used to contain biogas slurry, the first tank body (101) is located below the second tank body (201), and the inner cavity of the first tank body (101) is communicated with the inner cavity of the second tank body (201), and a top wall heating net (207) is provided on the top of the inner wall of the first tank body (101), wherein the top wall heating net (207) is used to heat the top of the inner wall of the first tank body (101) to prevent water vapor from condensing on the top of the inner wall of the first tank body (101).
3. The equipment for preparing carbon source from kitchen waste biogas slurry according to claim 2, characterized in that: The fully automatic anaerobic fermentation tank (1) further comprises: A stirrer (102), the stirrer (102) being arranged in the first tank (101), and the stirrer (102) being used to stir the biogas slurry to facilitate the reaction of the biogas slurry; A discharge port (103), the discharge port (103) being arranged at the bottom of the first tank body (101), and the discharge port (103) being used to discharge products remaining after the biogas slurry reaction; a water inlet (104), the water inlet (104) being arranged at the bottom of the first tank body (101), the water inlet (104) being used to add water into the first tank body (101); A feed inlet (105), the feed inlet (105) being arranged at the top of the first tank body (101), and the feed inlet (105) being used to add biogas slurry into the first tank body (101).
4. The equipment for preparing carbon source from kitchen waste biogas slurry according to claim 3, characterized in that: The fully automatic anaerobic fermentation tank (1) further comprises: An N2 inlet (106), the N2 inlet (106) being arranged at the top of the first tank body (101), the N2 inlet (106) being connected to a nitrogen-air integrated machine, the N2 inlet (106) being used to add biogas slurry N2 into the first tank body (101) to maintain an N2 atmosphere during the reaction process, the N2 inlet (106) being connected to an N2 conduit (1061) leading to the bottom of the first tank body (101), being used to extend into the biogas slurry during the reaction process to blow off NH3 generated during the reaction process; A water bath heating jacket (107), the water bath heating jacket (107) is disposed around the first tank body (101), and the water bath heating jacket (107) is used to heat the first tank body (101) to perform hydrothermal treatment on the biogas slurry.
5. The equipment for preparing carbon source from kitchen waste biogas slurry according to claim 4, characterized in that: The fully automatic anaerobic fermentation tank (1) further comprises: A monitoring mechanism (108), the monitoring mechanism (108) being arranged on the side wall of the first tank (101), the monitoring end of the monitoring mechanism (108) extending into the biogas slurry, the monitoring mechanism (108) being used to detect the pH value and temperature of the biogas slurry; An automatic liquid adding mechanism (109) is provided on the top of the first tank (101) and is used to add reactants to the first tank (101). The monitoring mechanism (108) includes a pH monitor (1081) and a temperature sensor (1082), and the automatic liquid adding mechanism (109) includes an Al 3+ Solution Adder (1091), Mg 2+ A solution adder (1092), an alkali solution adder (1093) and an acid solution adder (1094).
6. The equipment for preparing carbon source from kitchen waste biogas slurry according to claim 1, characterized in that: It also includes an ammonia recovery reaction tank (3), the ammonia recovery reaction tank (3) is connected to the top collecting tank (2), and the ammonia recovery reaction tank (3) is used to receive N2 and NH3 output from the top collecting tank (2); The ammonia recovery reaction tank (3) comprises: A third tank body (301), wherein the third tank body (301) is filled with water, and the liquid discharge pipe (205) and the air outlet (206) are both connected to the third tank body (301); A CO2 gas supply mechanism (302) is used to deliver CO2 to the third tank body (301).
7. A method for preparing a carbon source from kitchen waste biogas slurry, characterized in that: The steps include: S1. Adjust the pH of the food waste biogas to 9-10; S2, stirring in N2 atmosphere, and adding Mg dropwise 2+ Solution and Al 3+ solution; S3. After the precipitate appears, the suspension is subjected to hydrothermal treatment. After the reaction is completed, the precipitate is washed and collected to obtain a carbon resource product, wherein the hydrothermal treatment is performed at 70° C. for 24 hours. The carbon resource product is an organic acid-based double metal hydroxide; S4. During the hydrothermal treatment, water vapor is condensed at the top, and part of the NH3 generated by the reaction is dissolved in the condensate, and the other part is discharged to the ammonia recovery reaction device. At the same time, the condensate is also discharged to the ammonia recovery reaction device; S5 and CO2 are introduced into the ammonia recovery reaction device to form NH4HCO3 products which are crystallized and precipitated to obtain nitrogen resource products.
8. The method for preparing a carbon source from kitchen waste biogas slurry according to claim 7, characterized in that: In step S1, the kitchen waste biogas is obtained by anaerobic fermentation of kitchen waste and separation of fermentation residues; The method for anaerobic fermentation of food waste is as follows: food waste and deionized water are slurried in a mass ratio of 1:1, and then anaerobic fermentation is carried out. During the fermentation process, the temperature is controlled at 35°C, and the pH is adjusted and controlled at 5.0-6.
0. Natural fermentation is carried out without inoculating sludge, and the reaction time is 3 days. When adjusting the pH of the biogas slurry, use 4M NaOH or 4M HCl to adjust the pH.
9. The method for preparing a carbon source from kitchen waste biogas slurry according to claim 7, characterized in that: In step S2, Mg 2+ The solution is Mg(NO3)2 solution, Al 3+ The solution is Al(NO3)3 solution; Mg 2+ Mg in solution 2+ ions, Al 3+ Al in solution 3+ The ratio of ions and anaerobic fermentation liquid of food waste is 0.3mol:0.15mol:5L.