Multifunctional dry anaerobic fermentation device

Abstract

The invention relates to a multifunctional dry anaerobic fermentation device, and belongs to the technical field of anaerobic fermentation. Comprising a shell, an impurity removal mechanism, a backflow mechanism and a gas detection mechanism, a gas conveying opening is formed in the top face of the shell, a conveying opening is formed in the bottom face of the shell, the impurity removal mechanism is installed on the top face of the shell, the backflow mechanism is installed on the outer side wall of the shell, and the gas detection mechanism is installed at the gas outlet end of the impurity removal mechanism and detects gas subjected to impurity removal; marsh gas generated in the shell sequentially passes through the impurity removal mechanism and the backflow mechanism from the gas conveying opening and is finally discharged from the conveying opening to stir materials in the shell, and in the subsequent gas stirring process, the impurity removal time of the impurity removal mechanism is adjusted by the impurity removal mechanism according to the last detection result of the gas detection mechanism; the problems that the anaerobic fermentation efficiency and the gas production rate are influenced and the biogas power generation efficiency is reduced due to the fact that the concentration of impurities in the biogas is too high when gas stirring is adopted in the existing dry anaerobic fermentation process are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of anaerobic fermentation, and particularly relates to a multifunctional dry anaerobic fermentation device. Background Art

[0002] Biogas, also known as marsh gas, is the product of the decomposition and metabolism of organic substances (such as straw, weeds, human and animal feces, garbage, sludge, etc.) by various microorganisms under anaerobic conditions. Its main components are methane and nitrogen dioxide, and there are also small amounts of other gases such as hydrogen sulfide and water vapor. The process of biogas production is also called anaerobic fermentation. According to the total solid content, anaerobic digestion technology can be divided into wet anaerobic digestion (solid content < 15%) and dry anaerobic digestion (solid content 20 - 40%). The dry anaerobic process has the following obvious advantages: 1) It can adapt to solid organic waste from various sources; 2) Low operating cost and high volumetric gas production rate; 3) Low water requirement or no water required, and low subsequent treatment cost of residues; 4) Stable operation process, without problems such as scum and precipitation in the wet process.

[0003] Since the anaerobic process, especially the dry anaerobic fermentation process with a high solid content, the stirring of materials is a key factor in anaerobic gas production efficiency. Stirring directly determines the uniformity of material distribution, which in turn affects the contact between anaerobic microorganisms and materials and has an impact on the biochemical process. At the same time, it also has positive and negative feedback on heat transfer and mass transfer of materials. In engineering practice, it is found that compared with traditional mechanical stirring, dry anaerobic fermentation is more suitable for gas stirring. After the return biogas is pressurized and then input into the dry anaerobic fermentation tank, the anaerobic materials are stirred and disturbed, solving the problems of high energy consumption, large wear, and high failure rate of traditional mechanical stirring.

[0004] However, the biogas produced by anaerobic fermentation contains impurities. Therefore, during the process of returning biogas, the concentration of impurities carried in the biogas will gradually increase. Gases such as hydrogen sulfide and ammonia in the impurities will inhibit anaerobic microorganisms, thus affecting the efficiency and gas production of anaerobic fermentation. At the same time, the biogas produced by anaerobic fermentation is usually used for biogas power generation, but the impurities carried in these biogas will occupy the volume of the biogas, reducing the concentration of effective combustible gases (such as methane), thereby reducing the available energy and the power generation efficiency. Summary of the Invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a multifunctional dry anaerobic fermentation device, which solves the problems that the concentration of impurities in biogas is too high during gas stirring in the existing dry anaerobic fermentation process, affecting the efficiency and gas production of anaerobic fermentation, and at the same time reducing the biogas power generation efficiency.

[0006] The object of the present invention can be achieved by the following technical solutions: A multifunctional dry anaerobic fermentation device, including a housing, an impurity removal mechanism, a reflux mechanism and a gas detection mechanism. An air outlet is provided on the top surface of the housing, and a delivery port is provided on the bottom surface. The impurity removal mechanism is installed on the top surface of the housing, the reflux mechanism is installed on the outer side wall of the housing, and the gas detection mechanism is installed at the air outlet end of the impurity removal mechanism to detect the gas after impurity removal. The biogas generated in the housing passes through the impurity removal mechanism and the reflux mechanism in sequence from the air outlet, and finally is discharged from the delivery port to stir the materials in the housing. During the subsequent gas stirring process, the impurity removal mechanism adjusts the impurity removal time of the impurity removal mechanism according to the detection results of the gas detection mechanism last time.

[0007] As a preferred technical solution of the present invention, the impurity removal mechanism includes an impurity removal box and a condenser. The condenser is installed at the air inlet end of the impurity removal box. A purification chamber is provided in the impurity removal box, and the purification chamber is used to filter nitrogen, hydrogen sulfide and carbon dioxide gases.

[0008] As a preferred technical solution of the present invention, the purification chamber includes a filtration pool and a separation membrane. The separation membrane is installed on one side of the purification chamber close to the air outlet end and is used to filter carbon dioxide gas. A separation port is also provided in the purification chamber. A plurality of filtration cavities are provided in the filtration pool, and various filtration materials are filled in the filtration cavities to filter nitrogen and hydrogen sulfide.

[0009] As a preferred technical solution of the present invention, the condenser includes a connecting ring and a number of condensation plates. The connecting ring is installed on the inner side wall of the air outlet, and the condensation plates are installed on the bottom surface of the connecting ring. A number of the condensation plates enclose to form a triangular cone shape with the conical end facing the air outlet.

[0010] As a preferred technical solution of the present invention, a corrugated layer is provided on the outer surface of the condensation plate.

[0011] As a preferred technical solution of the present invention, the gas detection mechanism is composed of a multi-channel gas analyzer.

[0012] As a preferred technical solution of the present invention, the reflux mechanism includes a storage shell, a compression shell, a turbine and a driver. An air inlet is provided on the top surface of the storage shell, and an air outlet is provided on the bottom surface. The compression shell is a hollow shell with ventilation holes provided on both the side surface and the bottom surface. The driver is installed on the top surface of the compression shell and the output end is connected to the turbine. The turbine is rotatably connected inside the compression shell. Biogas enters the storage shell through the ventilation holes and the air inlet.

[0013] As a preferred technical solution of the present invention, a one-way valve is provided at the air inlet.

[0014] As a preferred technical solution of the present invention, an electromagnetic reversing valve and a gas transmission pipeline are further provided at the air outlet end of the impurity removal mechanism. The gas transmission pipeline is communicated with the air outlet end, and the electromagnetic reversing valve is installed at the air outlet end and controls the communication between the air outlet end and the gas transmission pipeline.

[0015] The beneficial effects of the present invention are as follows: The impurity removal mechanism removes impurities in the output biogas, and the gas detection mechanism is installed at the air outlet end of the impurity removal mechanism to detect the gas component content after impurity removal in the impurity removal mechanism. Then, the gas after impurity removal is discharged into the reflux mechanism for compression. Then, the reflux mechanism transports the compressed high-pressure air through the delivery port back into the shell to stir the materials in the shell to ensure the gas production efficiency of the materials in the shell. At the same time, when gas stirring is carried out next time, the impurity removal mechanism will adjust the impurity removal time of the impurity removal mechanism according to the detection results of the previous air pressure detection mechanism, so as to accurately remove the impurities in the biogas and ensure the impurity removal accuracy of the impurity removal mechanism. Thus, it solves the problems that in the existing dry anaerobic fermentation process, when gas stirring is used, the concentration of impurities in the biogas is too high, affecting the efficiency and gas production of anaerobic fermentation, and at the same time reducing the biogas power generation efficiency. Description of the Drawings

[0016] For the convenience of those skilled in the art to understand, the present invention will be further described below with reference to the accompanying drawings.

[0017] Figure 1 is a schematic structural diagram of the present invention;

[0018] Figure 2 is a schematic structural diagram of the impurity removal mechanism of the present invention;

[0019] Figure 3 is a schematic structural diagram of the condenser of the present invention;

[0020] Figure 4 is a schematic structural diagram of the reflux mechanism of the present invention;

[0021] Main Element Symbol Explanation

[0022] In the figure: 1, shell; 11, gas transmission port; 2, impurity removal mechanism; 21, impurity removal box; 22, condenser; 221, connecting ring; 222, condensation plate; 223, corrugated layer; 231, filtration tank; 232, separation membrane; 24, gas transmission pipeline; 25, electromagnetic reversing valve; 3, reflux mechanism; 31, storage shell; 32, compression shell; 33, turbine; 34, driver; 4, gas detection mechanism. Detailed Embodiments

[0023] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following, in combination with the accompanying drawings and preferred embodiments, details the specific embodiments, structures, features, and their effects of the present invention as follows.

[0024] Please refer to Figures 1 - 4 In this embodiment, a multi-functional dry anaerobic fermentation device is provided, which includes a housing 1, an impurity removal mechanism 2, a reflux mechanism 3 and a gas detection mechanism 4. An air outlet 11 is provided on the top surface of the housing 1, and a delivery port is provided on the bottom surface. The impurity removal mechanism 2 is installed on the top surface of the housing 1, and the reflux mechanism 3 is installed on the outer side wall of the housing 1. During anaerobic fermentation, the biogas generated will be discharged from the air outlet 11 and enter the impurity removal mechanism 2. The impurity removal mechanism 2 removes the impurities in the output biogas, and the gas detection mechanism 4 is installed at the air outlet end of the impurity removal mechanism 2 to detect the gas component content after impurity removal in the impurity removal mechanism 2, and then the gas after impurity removal is discharged into the reflux mechanism 3 for compression. Then, the reflux mechanism 3 transports the compressed high-pressure gas back into the housing 1 through the delivery port to stir the materials in the housing 1 to ensure the gas production efficiency of the materials in the housing 1.

[0025] At the same time, this completes one gas stirring process. During the continuous anaerobic fermentation process, the gas stirring cycle needs to be continuously carried out. Therefore, during the next gas stirring, the impurity removal mechanism 2 will adjust the impurity removal time of the impurity removal mechanism 2 according to the detection result of the previous pressure detection mechanism, so as to accurately remove the impurities in the biogas, ensure the impurity removal accuracy of the impurity removal mechanism 2, reduce the content of impurities in the biogas, and avoid the situation that the concentration of impurities carried in the biogas gradually increases during the process of refluxing biogas, which affects the efficiency and gas production of anaerobic fermentation.

[0026] During anaerobic fermentation, the main components of the biogas are methane and nitrogen dioxide, and there are also a small amount of other gases such as hydrogen sulfide and water vapor. Therefore, in order to remove the impurities in the biogas and reduce the content of impurities in the biogas, so as to improve the efficiency and production of anaerobic fermentation during the reflux gas stirring process, in this embodiment, the impurity removal mechanism 2 includes an impurity removal box 21 and a condenser 22. The condenser 22 is installed at the air inlet end of the impurity removal box 21. A purification chamber is provided in the impurity removal box 21, and the purification chamber is used to filter nitrogen, hydrogen sulfide and carbon dioxide gases. During impurity removal, first let the biogas pass through the condenser 22 to intercept the moisture carried in the biogas to avoid the influence of water vapor on the subsequent impurity removal process, and then let the biogas after removing moisture pass through the purification chamber to remove the remaining impurities.

[0027] Since the impurities in the biogas produced by anaerobic fermentation mainly include nitrogen, hydrogen sulfide and carbon dioxide gas, in one embodiment, the purification chamber includes a filtration tank 231 and a separation membrane 232. The separation membrane 232 is installed on one side of the purification chamber close to the gas outlet end and is used to filter carbon dioxide gas. The purification chamber is also provided with a separation opening. The filtration tank 231 is provided with a plurality of filtration chambers, and a variety of filtration materials are filled in the filtration chambers to filter nitrogen and hydrogen sulfide. The nitrogen and hydrogen sulfide are adsorbed or removed through the plurality of independent filtration chambers provided in the filtration tank 231, and then the carbon dioxide gas is filtered through the separation membrane 232, thereby reducing the impurity content in the biogas. Since the main components of the impurities in the biogas are nitrogen, hydrogen sulfide and carbon dioxide gas, but there will also be a small amount of other gases, therefore, if this part of the gas needs to be purified, the corresponding purification materials can be filled in the filtration tank 231 for filtration.

[0028] In the process of removing nitrogen, activated carbon materials can be used to adsorb nitrogen. Therefore, if the moisture is not removed sufficiently before the activated carbon adsorption, the moisture may saturate the activated carbon and reduce its adsorption capacity. Therefore, in one embodiment, in order to reduce the situation that the filtration tank 231 is affected by moisture during the process and the filtration effect is reduced, the condenser 22 includes a connecting ring 221 and a plurality of condensation plates 222. The connecting ring 221 is installed on the inner side wall of the gas inlet 11, and the condensation plates 222 are installed on the bottom surface of the connecting ring 221. The plurality of condensation plates 222 enclose a triangular cone shape with the tapered end facing the gas inlet 11. When the biogas passes through the condensation plates 222, the temperature of the moisture in the biogas can be reduced to condense the water vapor to achieve the filtration effect. At the same time, the biogas can pass along the surface of the condensation plates 222 through the triangular cone shape formed by the plurality of condensation plates 222, so that the moisture in the biogas can fully contact the condensation plates 222 to condense the water vapor, thereby reducing the moisture content in the gas.

[0029] In order to further improve the condensation effect of the condensation plates 222, in one embodiment, the outer surface of the condensation plates 222 is provided with a wrinkled layer 223. When the biogas passes through the condensation plates 222, the wrinkled layer 223 on the surface of the condensation plates 222 will increase the contact area between the biogas and the condensation plates 222, so that the water vapor in the biogas can more effectively contact the condensation surface. Moreover, the wrinkles can increase the turbulence degree of the gas flow, promote the heat exchange between the gas and the condensation plates 222, and improve the cooling and condensation efficiency.

[0030] Since there are many types of impurities in biogas, in order to improve the detection of the content of impurity gases and at the same time improve the impurity removal effect of impurity gases, in one embodiment, the gas detection mechanism 4 is composed of a multi-channel gas analyzer. The multi-channel gas analyzer is usually equipped with multiple sensors, each sensor responds to a specific gas component. The sensor signals collected by the analyzer can be processed to calculate the concentration of each gas component, and the results are displayed or transmitted. Moreover, the multi-channel design can improve the detection sensitivity of low-concentration gases, ensuring that even trace impurities can be identified, thus ensuring that the impurity removal mechanism 2 can accurately control the impurity removal time during impurity removal.

[0031] In order to accurately control the impurity removal time of each gas, solenoid valves can be set in each filter chamber to control the residence time of the gas, so as to better remove the impurity gases.

[0032] As Figure 1 shown, the intake end of the reflux mechanism 3 is connected to the outlet end of the impurity removal mechanism 2 through a connecting pipe (the connecting pipe is not shown in the figure). Since the gas stirring method is adopted during the anaerobic fermentation process, in order to ensure the gas stirring effect, it is necessary to make the gas output from the delivery port have sufficient impact force to ensure that a strong gas reflux can be generated in the housing 1 to achieve the stirring effect. In one embodiment, the reflux mechanism 3 includes a storage shell 31, a compression shell 32, a turbine 33 and a driver 34. The top surface of the storage shell 31 is provided with an air inlet, and the bottom surface is provided with an air outlet. The compression shell 32 is a hollow housing 1 and is provided with ventilation holes on both the side and the bottom surface. The driver 34 is installed on the top surface of the compression shell 32 and the output end is connected to the turbine 33. The turbine 33 is rotatably connected inside the compression shell 32. Biogas enters the storage shell 31 through the ventilation holes from the air inlet. When the biogas impurity removal is completed, the biogas will enter the compression shell 32 from the air inlet, and then the driver 34 compresses the biogas in the compression shell 32 by rotating the turbine 33 and enters the storage shell 31 for storage, so that the gas transported from the delivery port can be high-pressure gas to generate a strong air flow in the housing 1 to achieve a good stirring effect.

[0033] Moreover, the compressed gas will have a certain temperature, thus avoiding reducing the temperature inside the housing 1 when a new gas is input into the housing 1, which may cause the temperature inside the housing 1 to fluctuate and affect the efficiency and gas production of anaerobic fermentation.

[0034] In order to ensure that the gas in the storage shell 31 can maintain a high-pressure state, in one embodiment, a one-way valve is provided at the air inlet. By means of the one-way valve, it can be ensured that the gas in the storage shell 31 will not flow back, effectively preventing the high-pressure gas in the storage shell from flowing back through the air inlet and maintaining the air pressure stability in the storage shell 31, so as to ensure that a strong gas swirl can be formed during transportation to complete the stirring.

[0035] Since the biogas in the anaerobic fermentation process is not only used for gas stirring but also for biogas power generation, in order to ensure that the biogas can be smoothly transported to complete biogas power generation while also performing the function of gas stirring, in one embodiment, an electromagnetic directional valve 25 and a gas transmission pipeline 24 are further provided at the gas outlet end of the impurity removal mechanism 2. The gas transmission pipeline 24 communicates with the gas outlet end. The electromagnetic directional valve 25 is installed at the gas outlet end and controls the communication between the gas outlet end and the gas transmission pipeline 24. Since biogas is continuously generated during the anaerobic fermentation process, and this part of the biogas needs to first meet the gas required for gas stirring, the gas continuously generated during the anaerobic fermentation process also needs to be processed in a timely manner to avoid the occurrence of too high air pressure in the housing 1. Therefore, the electromagnetic directional valve 25 is used to control the communication between the gas transmission pipeline 24 and the biogas power generation pipeline, so that the purified biogas can enter the biogas power generation pipeline to complete biogas power generation.

[0036] The above is only a preferred embodiment of the present invention and does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments by using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A multifunctional dry anaerobic fermentation device, characterized in that: It includes a shell, a dust removal mechanism, a reflux mechanism and a gas detection mechanism. The top surface of the shell is provided with a gas transmission port, and the bottom surface is provided with a delivery port. The dust removal mechanism is installed on the top surface of the shell, and the reflux mechanism is installed on the outer side wall of the shell. The gas detection mechanism is installed on the gas outlet end of the dust removal mechanism and detects the gas after dust removal. The biogas generated in the shell passes through the dust removal mechanism and the reflux mechanism in sequence from the gas transmission port, and is finally discharged from the delivery port to stir the material in the shell. In the subsequent gas stirring process, the dust removal mechanism adjusts the dust removal time of the dust removal mechanism according to the detection result of the gas detection mechanism last time.

2. A multifunctional dry anaerobic fermentation device according to claim 1, characterized in that: The impurity removal mechanism comprises an impurity removal box and a condenser. The condenser is installed at the air inlet end of the impurity removal box. A purification chamber is arranged in the impurity removal box. The purification chamber is used to filter nitrogen, hydrogen sulfide and carbon dioxide gas.

3. A multifunctional dry anaerobic fermentation device according to claim 2, characterized in that: The purification chamber includes a filter pool and a separation membrane. The separation membrane is installed on one side of the purification chamber close to the gas outlet and is used to filter carbon dioxide gas. The purification chamber is also provided with a separation port. A plurality of filter cavities are provided in the filter pool. The filter cavities are filled with a plurality of filter materials for filtering nitrogen and hydrogen sulfide.

4. A multifunctional dry anaerobic fermentation device according to claim 2, characterized in that: The condenser comprises a connecting ring and a plurality of condensation plates, wherein the connecting ring is mounted on the inner side wall of the gas delivery port, and the condensation plates are mounted on the bottom surface of the connecting ring, and the plurality of condensation plates are enclosed to form a triangular cone with the cone end facing the gas delivery port.

5. A multifunctional dry anaerobic fermentation device according to claim 4, characterized in that: The outer surface of the condensation plate is provided with a corrugated layer.

6. The multifunctional dry anaerobic fermentation device according to claim 1, characterized in that: The gas detection mechanism is composed of a multi-channel gas analyzer.

7. The multifunctional dry anaerobic fermentation device according to claim 1, characterized in that: The reflux mechanism includes a storage shell, a compression shell, a turbine and a driver. The storage shell is provided with an air inlet on the top surface and an air outlet on the bottom surface. The compression shell is a hollow shell with air vents on the side and bottom surfaces. The driver is mounted on the top surface of the compression shell and the output end is connected to the turbine. The turbine is rotatably connected to the compression shell, and the biogas enters the storage shell from the air vent through the air inlet.

8. A multifunctional dry anaerobic fermentation device according to claim 7, characterized in that: A one-way valve is arranged at the air inlet.

9. The multifunctional dry anaerobic fermentation device according to claim 1, characterized in that: The air outlet of the impurity removal mechanism is also provided with an electromagnetic reversing valve and an air supply pipeline, the air supply pipeline is communicated with the air outlet, and the electromagnetic reversing valve is installed at the air outlet and controls the air outlet to communicate with the air supply pipeline.

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