Continuous high-solid content anaerobic fermentation equipment and use method thereof

Abstract

The present invention discloses a continuous high-solid content anaerobic fermentation equipment and a method for using the same, which belongs to the technical field of waste treatment and resource utilization. It includes a horizontal anaerobic fermentation bin, a hydraulically driven plug-flow low-speed strong mixing and stirring system arranged in the horizontal anaerobic fermentation bin, a multi-material collaborative feeding system, and a temperature and power collaborative control system. The present invention abandons the reducer stirring method and adopts a hydraulically driven low-speed strong mixing and stirring method. At the same time, the angle, spacing and distribution of the stirring blades on the stirring shaft are designed so that the blade spacing is 50 cm, the blade plane is 67° to the axial direction, and the clockwise single-side blades are arranged in sequence at 90°. This design has no dead zone in the transmission of 20%±10% high-solid content materials and the low stirring process of 1 degree / second, thereby achieving low-energy consumption and full mixing of high-solid content organic solid waste and ensuring full fermentation of each material in the fermentation bin; at the same time, the material can be continuously processed, and the fermentation residues produced can be fully composted.

Description

Technical Field

[0001] The present invention relates to the technical field of waste treatment and resource utilization, and in particular to a continuous high-solid content anaerobic fermentation equipment and a use method thereof. Background Art

[0002] Currently, my country's organic waste is characterized by large production volumes and diverse types. These diverse sources primarily include kitchen waste, garden waste, sludge from urban sewage treatment plants, human feces, and agricultural waste such as livestock and poultry manure and straw. Statistics show that my country produces approximately 3.8 billion tons of livestock and poultry manure and 1 billion tons of crop straw annually, necessitating the development of efficient and coordinated treatment solutions.

[0003] The development and utilization of biomass energy has become a hot topic of research and development in various countries. As one of the important ways to develop and utilize biomass energy, anaerobic fermentation technology plays an important role in the treatment and utilization of biomass resources such as agricultural waste and urban garbage with its advantages of high energy efficiency, low pollution and renewability. At present, my country's biogas anaerobic fermentation mainly focuses on wet anaerobic fermentation such as CSTR. Although the technology is relatively mature, it still has problems such as low volumetric gas production rate, high energy consumption, high water consumption, large wastewater production and difficulty in treatment. The more advanced biogas projects abroad mostly use dry fermentation technology with a solid content greater than 20%. Dry anaerobic fermentation has the following advantages: 1) low water demand, less biogas liquid produced, and reduced treatment costs; 2) high volumetric productivity and high organic load rate per unit volume; 3) relatively simple pretreatment of organic solid waste. However, traditional dry anaerobic fermentation also has certain defects: 1) It is mainly based on batch processes such as composting and leaching, which makes heat and mass transfer difficult and the fermentation efficiency low; 2) Some continuous dry fermentations are subject to the level of automatic control, and the stirring devices used are severely worn in contact with the solid raw materials, and there are large stirring dead angles. In addition, most of them use reducers for stirring, which have a fast stirring speed and high energy consumption; 3) The anaerobic fermentation microorganisms are in uneven contact with the reaction substrate, and the fermentation cycle is long; 4) The moisture content of the materials is low, and there is serious heterogeneity.

[0004] High-solids anaerobic fermentation technology not only has the advantages of dry anaerobic fermentation, but also can effectively solve the problems of low heat transfer efficiency, uneven mass transfer, large equipment wear, and uneven contact between substrate and inoculum. However, the current high-solids anaerobic fermentation reactor is only suitable for treating organic solid waste with solid contents of about 10% and 25%. The solid content of about 10% is too low, which will produce a large amount of biogas slurry and increase treatment costs. The solid content of about 25% is too high, resulting in high equipment costs and poor homogeneity. For example, there is a "high-solid content fully mixed anaerobic reactor (CN202211385495.5)", which processes materials with a solid content of about 10%. It is only suitable for small fermentation systems, has a low level of intelligent control, and a processing volume of about 10L. It is difficult to continuously process organic solid waste, and the fermentation residues need to be further filtered. The "horizontal flow anaerobic digestion reaction device and method for treating high-solid content kitchen waste (CN202011300516.X)" is mainly aimed at the treatment of high-solid content food waste with a solid content ≥25%. It is equipped with multiple stirring devices, has a complex structure, and high energy consumption, which increases the difficulty of waste treatment and reduces treatment efficiency.

[0005] Therefore, the development of an anaerobic fermentation reactor with a high level of automation control, the ability to continuously process multiple organic solid wastes, a simple structure, easy adjustment of the properties of the initial materials, and uniform stirring has become an urgent need to promote the development of the industry. Summary of the Invention

[0006] The purpose of the present invention is to provide a continuous high-solid content anaerobic fermentation equipment and its use method, so as to solve the problems mentioned in the above background technology, such as the complex structure, low level of intelligent control, poor homogeneity, and difficulty in continuously treating multiple organic solid wastes of the current high-solid content anaerobic fermentation reactor. It can realize the continuous treatment of high-solid content multiple organic solid wastes, the organic solid wastes are fully mixed in the reactor, the fermentation residues produced can be fully composted, and it is equipped with an integrated intelligent control system.

[0007] To achieve the above object, the present invention provides a continuous high solid content anaerobic fermentation equipment, comprising:

[0008] Multi-material collaborative feeding system, used to process multi-organic solid waste with high solid content;

[0009] A horizontal anaerobic fermentation chamber is connected to the multi-material coordinated feeding system via a conveying pipeline and is used to ferment the treated high-solid content multi-organic solid waste;

[0010] A hydraulically driven plug-flow low-speed strong mixing and stirring system is provided in the horizontal anaerobic fermentation chamber and is used to stir multi-organic solid waste with a high solid content;

[0011] The temperature and power coordinated control system drives the hydraulically driven plug-flow low-speed strong mixing and stirring system and the multi-material coordinated feeding system.

[0012] Preferably, the hydraulically driven plug-flow low-speed intensive mixing system includes a stirring shaft disposed within the fermentation chamber, with stirring blades evenly distributed on the stirring shaft. One end of the stirring shaft is connected to the stirring chamber via a first bearing seat, and the other end passes through the fermentation chamber via a second bearing seat and is connected to an external hydraulic drive device, which is connected to a hydraulic station. The use of hydraulic agitation to provide power transmission avoids the conventional reduction gear agitation method, enabling effective agitation even at low speeds, avoiding energy waste and saving energy consumption.

[0013] Preferably, the axial spacing between each stirring blade on the stirring shaft is 50 cm, and there is only one single-sided stirring blade at each blade point on the stirring shaft. Each stirring blade is arranged clockwise at a 90° angle to the stirring blade on the axial direction, and the plane of the stirring blade is distributed on the stirring shaft at a 67° angle to the axial direction. The use of hydraulic stirring combined with the angle, spacing, and shape design of the stirring blades can achieve uniform and dead-angle-free stirring of the material under slow stirring conditions, saving energy while improving stirring efficiency, thereby improving the fermentation efficiency of the device.

[0014] Preferably, the rotation speed of the stirring shaft is 1° per second, three revolutions per hour, and each revolution takes 6 minutes.

[0015] Preferably, the diameter of the stirring shaft is 27.3 cm, the stirring blade is a long strip with a 1 / 4 circle top and parallel sides, the blade width is 20 cm, and the centerline length of the stirring blade is 37.2% of the height of the horizontal anaerobic fermentation chamber.

[0016] Preferably, the horizontal anaerobic fermentation chamber comprises a fermentation box body, an observation port and a biogas outlet are provided on the top of the fermentation box body, and an electric auxiliary heating component and a radar liquid level detection device are provided inside the fermentation box body.

[0017] Preferably, the multi-material collaborative feeding system includes a feeding bin, which is connected to an external water pipeline. An automatically controlled spiral stirring shaft is provided in the feeding bin, the top of the spiral stirring shaft is connected to the motor output shaft, and a conveying screw pump is provided at the bottom of the feeding bin, so that one person can easily complete all feeding work.

[0018] Preferably, the temperature and power coordinated control system includes an intelligent control system, which integrates a hydraulically driven plug-flow low-speed strong mixing and stirring system, a multi-material coordinated feeding system and an electric auxiliary heating component for integrated control.

[0019] The present invention also provides a method for using the above-mentioned continuous high-solid content anaerobic fermentation equipment, comprising the following steps:

[0020] Step 1: During the initial fermentation, anaerobic sludge is added to the feed bin, and the delivery screw pump is turned on to deliver the inoculum to the fermentation tank until the volume of the inoculum in the fermentation tank reaches 1 / 3 of the volume of the fermentation tank;

[0021] Step 2: Heat the temperature of the fermentation box to 35±1℃ or 55±1℃ through the electric auxiliary heating component;

[0022] Step 3: Add 1-2m3 of water into the feed bin every day. 3 For high-solid content multi-organic solid waste, open the water pipeline to adjust the solid content to 15%-20%, use the spiral stirring shaft to stir it evenly, then turn on the delivery screw pump to transport it to the fermentation box, and use the hydraulically driven plug flow low-speed strong mixing system's stirring shaft to stir it;

[0023] Step 4: When the internal material of the fermentation box reaches 2 / 3 of the box volume, turn on the discharge motor and regularly output the same volume of anaerobic fermentation residue from the discharge port according to the feed amount.

[0024] Therefore, the present invention adopts the above-mentioned continuous high solid content anaerobic fermentation equipment and its use method, and the specific beneficial effects are as follows:

[0025] (1) The stirring system of the present invention adopts a hydraulically driven single-axis push-flow stirring system, and combines the angle, spacing, and shape design of the stirring blades on the stirring shaft. The operation effect is measured by simulation, and the solid content in different areas is measured to measure the actual operation effect. It has been verified that it has the advantages of simple structure, few stirring dead angles, and low energy consumption. It can achieve uniform stirring of materials without dead angles under low-speed stirring conditions, save energy consumption, and improve stirring efficiency, thereby improving the fermentation efficiency and overall energy efficiency of the device;

[0026] (2) The device of the present invention can realize the continuous treatment of multi-organic solid waste with high solid content, which helps to reduce the waiting time between batches and improve the consistency and stability of the overall treatment process;

[0027] (3) The feed port of the present invention adopts a multi-material collaborative feeding system. The material input feed port can easily adjust the moisture content of the material, and accelerate the input of high-solid content materials into the fermentation bin through spiral stirring, so as to better realize the continuous automatic processing and automatic feeding of multi-materials. One person can complete all operations;

[0028] (4) The present invention uses intelligent integrated control of stirring time and real-time detection of key anaerobic fermentation parameters such as the temperature of the horizontal anaerobic fermentation chamber by radar, thereby ensuring uniform temperature in the fermentation chamber, avoiding local high temperature, and achieving precise heating, reducing energy consumption, and coordinating the control of the feeding / discharging device, which is simple and convenient to operate;

[0029] (5) The biogas generated by the present invention is directly used to generate electricity, which is used to power the electric auxiliary heating components of the system, thereby improving the energy efficiency and environmental benefits of the entire system.

[0030] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a front view of the equipment provided by Example 1 of the present invention;

[0032] Figure 2 is a side view of the equipment provided in Example 1 of the present invention;

[0033] Figure 3 is the volumetric gas production rate of anaerobic fermentation during the continuous feeding period of the equipment provided in Example 2 of the present invention;

[0034] Figure 4 is the methane concentration of anaerobic fermentation during the continuous feeding period of the equipment provided in Example 2 of the present invention;

[0035] Figure 5 This is a velocity cloud diagram of an anaerobic fermentation reactor provided in Example 2 of the present invention;

[0036] Reference numerals

[0037] 1. Power support plate; 2. Hydraulic drive device; 3. Second bearing seat; 4. Frame; 5. Stirring shaft; 6. Fermentation box; 7. Stirring blades; 8. Biogas outlet; 9. Observation port; 10. First bearing seat; 11. Discharge port; 12. Conveying screw pump; 13. Feed hopper; 14. Hydraulic station; 15. Spiral stirring shaft; 16. Water pipeline; 17. Motor; 18. Feed port; 19. Conveying pipeline; 20. Intelligent control system; 21. Electric auxiliary heating component. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.

[0039] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar terms used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0040] Example 1

[0041] like Figure 1-2 As shown, this embodiment discloses a continuous high-solid content anaerobic fermentation equipment, including a horizontal anaerobic fermentation tank, a hydraulically driven plug-flow low-speed strong mixing and stirring system arranged in the horizontal anaerobic fermentation tank, a multi-material coordinated feeding system, and a temperature and power coordinated control system. The high-solid content multi-organic solid waste is transported to the horizontal anaerobic fermentation tank through the multi-material coordinated feeding system through the conveying pipe 19, and then the high-solid content multi-organic solid waste is mixed and fermented with the inoculum through the hydraulically driven plug-flow low-speed strong mixing and stirring system, thereby ensuring that each organic solid waste in the horizontal anaerobic fermentation tank is fully fermented and the fermentation quality is guaranteed. The temperature and power coordinated control system drives the hydraulically driven plug-flow low-speed strong mixing and stirring system and the multi-material coordinated feeding system.

[0042] The multi-material coordinated feeding system is used to process high-solids multi-organic solid waste. It includes a feed silo 13 connected to an external water pipeline 16. A spiral stirring shaft 15 is installed within the feed silo 13. The top of the spiral stirring shaft 15 is connected to the output shaft of a motor 17. A delivery screw pump 12 is installed at the bottom of the feed silo 13. Multi-organic solid waste can be directly fed into the feed silo 13. Water is delivered through the water pipeline 16 to adjust the water content to an appropriate level. The spiral stirring shaft 15 accelerates the material input into the horizontal anaerobic fermentation chamber, increasing the material feed rate.

[0043] The horizontal anaerobic fermentation tank is provided with a feed port 18 at the lower end, which is connected to the multi-material coordinated feeding system via a conveying pipe 19. The tank includes a fermentation chamber 6, with two circular observation ports 9 and a biogas outlet 8 located above the fermentation chamber 6. The biogas outlet 8 is located at the center of the upper portion of the fermentation chamber 6, and the observation ports 9 are located on either side of the biogas outlet 8. A frame 4 is provided on the outside of the fermentation chamber 6, and electric auxiliary heating components 21 are provided on the left, right, and bottom sides of the fermentation chamber 6. The electric auxiliary heating components 21 consist of heating pipes and insulation cotton.

[0044] The hydraulically driven, plug-flow, low-speed, high-intensity mixing system includes a stirring shaft 5 disposed within a fermentation chamber 6. Sixteen stirring blades 7 are evenly distributed along the stirring shaft 5, with each stirring blade spaced 50 cm apart axially. Each blade position on the stirring shaft 5 contains only one single stirring blade 7. Each stirring blade 7 is arranged clockwise at 90° angles to the preceding stirring blade 7, with the stirring blades 7 distributed at 67° angles along the stirring shaft 5. One end of the stirring shaft 5 is connected to the stirring chamber via a first bearing block 10. The other end passes through the fermentation chamber 6 and is connected to an external hydraulic drive unit 2 via a second bearing block 3. The hydraulic drive unit 2 is fixed to a power support plate 1, and its lower end is connected to a hydraulic station 14 for hydraulic power. The stirring shaft 5 rotates at a speed of 1° per second, making only three revolutions per hour, a single revolution taking six minutes. The rest of the time, the power is disconnected.

[0045] The diameter of the stirring shaft is 27.3 cm, the stirring blade is a long strip with a 1 / 4 circle top and parallel sides, the blade width is 20 cm, and the centerline length of the stirring blade is 37.2% of the height of the horizontal anaerobic fermentation chamber.

[0046] The temperature and power coordinated control system includes an intelligent control system 20, which integrates a hydraulically driven plug-flow low-speed strong mixing and stirring system, a multi-material coordinated feeding system and an electric auxiliary heating component 21 for integrated control. The stirring time is controlled by setting parameters on the interface of the intelligent control system 20, and the temperature of the horizontal anaerobic fermentation bin and other key anaerobic fermentation parameters are detected in real time by radar, and the feeding / discharging device is controlled in a coordinated manner, which is simple and convenient to operate.

[0047] Example 2

[0048] This embodiment provides a method for using the above-mentioned continuous high-solids anaerobic fermentation equipment, comprising the following steps:

[0049] Step 1: During the initial fermentation, anaerobic sludge is added to the feed bin 13, and the delivery screw pump 12 is turned on to deliver the inoculum to the fermentation tank 6 until the volume of the inoculum in the fermentation tank 6 reaches 1 / 3 of the volume of the fermentation tank 6;

[0050] Step 2: Heat the temperature of the fermentation box 6 to 35° C. through the electric auxiliary heating component 21;

[0051] Step 3: Add 2m3 of water into the feed bin 13 every day. 3 The high solid content multi-organic solid waste is opened and the solid content is adjusted to 18%. The spiral stirring shaft 15 is used to stir it evenly, and then the delivery screw pump 12 is turned on to transport it to the fermentation box 6. The stirring shaft 5 of the hydraulically driven plug flow low-speed strong mixing and stirring system is used for stirring;

[0052] Step 4: When the volume of the fermentation box 6 reaches 2 / 3 of the box volume, the discharge motor is turned on to periodically discharge the same volume of anaerobic fermentation residue from the discharge port 11 according to the feed amount.

[0053] The continuous high solid content anaerobic fermentation equipment of the present invention is used to treat multiple high solid content organic wastes, such as Figure 3 and 4 It can be seen that the volumetric gas production rate is equivalent to that of dry anaerobic fermentation. After testing, the volumetric gas production rate of anaerobic fermentation can reach a maximum of 2.1 m 3 ·m -3 ;

[0054] Depend on Figure 5 It can be seen that the use of the plug-flow stirring shaft 5 and the hydraulic drive method to stir the material can effectively reduce the stirring dead zone.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A continuous high solid content anaerobic fermentation equipment, characterized in that: include: Multi-material collaborative feeding system, used to process multi-organic solid waste with high solid content; A horizontal anaerobic fermentation chamber is connected to the multi-material coordinated feeding system via a conveying pipeline and is used to ferment the treated high-solid content multi-organic solid waste. The horizontal anaerobic fermentation chamber includes a fermentation box; A hydraulically driven plug-flow low-speed strong mixing and stirring system is provided in the horizontal anaerobic fermentation chamber and is used to stir multi-organic solid waste with a high solid content; A temperature and power coordinated control system drives the hydraulically driven plug-flow low-speed strong mixing and stirring system and the multi-material coordinated feeding system; The hydraulically driven plug-flow low-speed strong mixing and stirring system includes a stirring shaft arranged in the fermentation box, and stirring blades are evenly distributed on the stirring shaft. One end of the stirring shaft is connected to the fermentation box through a first bearing seat, and the other end passes through the fermentation box and is connected to an external hydraulic drive device through a second bearing seat. The hydraulic drive device is connected to a hydraulic station; The axial spacing between each stirring blade on the stirring shaft is 50 cm, and there is only one single-sided stirring blade at each blade point on the stirring shaft. Each stirring blade is arranged in a clockwise direction at an angle of 90° to the stirring blade on the axial direction, and the plane of the stirring blade is distributed on the stirring shaft at an angle of 67° to the axial direction; The diameter of the stirring shaft is 27.3 cm, the stirring blade is a long strip with a top that is 1 / 4 circle and two parallel sides, the blade width of the stirring blade is 20 cm, and the centerline length of the stirring blade is 37.2% of the height of the horizontal anaerobic fermentation chamber; The rotation speed of the stirring shaft is 1° per second, three revolutions per hour, and each revolution takes 6 minutes.

2. The continuous high solid content anaerobic fermentation equipment according to claim 1, characterized in that: An observation port and a biogas outlet are provided on the top of the fermentation box, and an electric auxiliary heating component and a radar liquid level detection device are provided inside.

3. The continuous high solid content anaerobic fermentation equipment according to claim 2, characterized in that: The multi-material collaborative feeding system includes a feeding bin, which is connected to an external water pipeline. A spiral stirring shaft is provided in the feeding bin, the top of the spiral stirring shaft is connected to the motor output shaft, and a conveying screw pump is provided at the bottom of the feeding bin.

4. The continuous high solid content anaerobic fermentation equipment according to claim 3, characterized in that: The temperature and power coordinated control system includes an intelligent control system, which integrates a hydraulically driven plug-flow low-speed strong mixing and stirring system, a multi-material coordinated feeding system and an electric auxiliary heating component for integrated control.

5. A method for using the continuous high-solid content anaerobic fermentation equipment according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: During the initial fermentation, anaerobic sludge is added to the feed bin, and the delivery screw pump is turned on to deliver the inoculum to the fermentation tank until the volume of the inoculum in the fermentation tank reaches 1 / 3 of the volume of the fermentation tank; Step 2: Heat the temperature of the fermentation box to 35±1℃ or 55±1℃ through the electric auxiliary heating component; Step 3: Add 1-2m3 of water into the feed bin every day. 3 For high-solid content multi-organic solid waste, open the water pipeline to adjust the solid content to 15%-20%, use the spiral stirring shaft to stir it evenly, then turn on the delivery screw pump to transport it to the fermentation box, and use the hydraulically driven plug flow low-speed strong mixing system's stirring shaft to stir it; Step 4: When the internal material of the fermentation box reaches 2 / 3 of the box volume, turn on the discharge motor and regularly output the same volume of anaerobic fermentation residue from the discharge port according to the feed amount.

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