Medium-temperature dry fermentation system for kitchen residues and kitchen waste organic matters

Abstract

The utility model relates to the technical field of mixed fermentation of kitchen waste and kitchen waste, and discloses a medium-temperature dry fermentation system of kitchen waste and kitchen waste organic matter, which comprises a material mixing unit, a medium-temperature dry fermentation unit and a post-treatment unit which are communicated through pipelines, the material mixing unit comprises a material pit, a transfer device and a material mixer which are communicated, the transfer device comprises a grab bucket and an inclined material guide arc plate, and one end of the material guide arc plate extends into the mixer. The kitchen waste organic matters still contain 10-20% of impurities such as plastics and fibers, so that equipment is easy to wind and block. Holes are easily formed after the organic matters are degraded, and equipment is easily blocked after impurities around the holes are settled; according to the scheme, the kitchen residues, the kitchen waste organic matter and the biogas residues and sludge are subjected to mixed fermentation, the kitchen residues can provide the organic matter and can also provide support for mixed organic matter, and mixed materials are prevented from settling and blocking equipment. According to the scheme, the mixing unit is additionally arranged, so that the mixing and homogenizing effects, namely the fermentation efficiency and the fermentation effect, of the mixed organic matters are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of mixed fermentation of food waste and kitchen waste, and particularly to a medium-temperature dry fermentation system for food waste residues and kitchen waste organic matter. Background Art

[0002] Food waste and kitchen waste have a high solid content and a high organic matter content. Direct landfilling is likely to cause pollution to groundwater, the atmosphere, etc., while incineration requires a large amount of additional fuel. Therefore, anaerobic fermentation is mainly used for resource utilization in China. As a technology for treating organic waste and converting it into bioenergy, the complexity of anaerobic fermentation lies in that it is restricted by various factors including raw material components, particle size, pH value, and ammonia nitrogen level, and these factors are directly related to fermentation efficiency and gas production capacity. In actual operation, due to the complex composition of food waste and kitchen waste, anaerobic fermentation will face problems such as stratification, acidification, uneven heating, and reduced fermentation efficiency, seriously affecting the stability and economy of the anaerobic fermentation system.

[0003] Currently, anaerobic fermentation technologies are divided into two major categories: wet and dry. The wet anaerobic fermentation technology is relatively mature, but its application scope is severely restricted by the requirement of "low-solid-content materials". In contrast, dry anaerobic fermentation is widely used and becoming increasingly mature globally due to its advantages of treating high-solid-content waste (25% - 45%), smaller floor area, low energy consumption, and less biogas slurry production.

[0004] The prior art CN214937410U discloses a mixed dry anaerobic fermentation treatment system for food waste and kitchen waste, which can treat food waste and kitchen waste simultaneously, reduce the production of biogas slurry, correspondingly reduce the later-stage biogas slurry treatment cost, and reduce the economic cost. However, when the prior art mixes and processes food waste and kitchen waste, there are still the following technical problems: (1) In the existing mixed dry anaerobic fermentation equipment, the mixing fermentation efficiency is easily reduced due to uneven mixing of various raw materials; even due to uneven mixing of materials and high impurity gas content, the mixed organic matter will instead form a high load, resulting in high ammonia nitrogen content and ammonia nitrogen inhibiting gas production, and then leading to the phenomenon of "system instability" and even system collapse; (2) In the existing mixed fermentation, even if the particle sizes of various raw materials are small, it is still easy for ductile impurities such as cloth strips and plastics in the waste to entangle with each other and remix into strip-shaped objects during the mixing process, which will entangle the equipment, resulting in increased equipment damage and increased equipment maintenance costs; (3) After the strip-shaped objects in the existing waste entangle the equipment, it is necessary to stop work for cleaning, reducing the operation stability and continuity of the system equipment, and thus resulting in low treatment efficiency.

[0005] In view of this, developing a medium-temperature dry fermentation system for food waste residues and kitchen waste organic matter can not only effectively make up for the deficiencies of the prior art, but also effectively improve the mixed fermentation effect of the two and increase the recovery rate of organic matter in the waste. Summary of the Invention

[0006] The present invention aims to provide a medium-temperature dry fermentation system for kitchen waste and kitchen organic matter, so as to solve the technical problem that when the existing fermentation system processes mixed fermentation, the mixing fermentation efficiency is reduced due to uneven mixing of each raw material, resulting in a relatively low recovery rate of organic matter in kitchen waste and kitchen garbage.

[0007] To achieve the above object, the present invention adopts the following technical solution: A medium-temperature dry fermentation system for kitchen waste and kitchen organic matter, including a mixing unit, a medium-temperature dry fermentation unit and a post-treatment unit connected by pipelines. The mixing unit includes a material pit, a transfer device and a mixer connected in sequence; the mixer includes a base, a mixing cylinder rotatably connected to the base and a driving mechanism for driving the mixing cylinder to rotate. The two ends of the mixing cylinder are respectively a feed end and a discharge end. The mixing cylinder is inclined, and the feed end is higher than the discharge end. A mixing and dispersing section is arranged in the mixing cylinder, and segmented spiral blades are arranged in the mixing and dispersing section.

[0008] The principle and advantages of this solution are as follows:

[0009] 1. Compared with the existing fermentation system that can only process one raw material, resulting in poor fermentation effect, this solution improves the fermentation effect and further improves the recovery rate of organic matter in kitchen waste and kitchen garbage by setting a mixing unit to fully mix raw materials from different sources before fermentation, so that each raw material can give full play to its respective role. Specifically, since the kitchen organic matter still contains 10-20% impurities (including 3-5% sand, plastic, fiber and other impurities), it is easy to cause equipment entanglement and blockage. And after the organic matter degrades, the solid content of the material will decrease, and then a series of cavities will be formed. After the impurities around the cavities settle, it is easy to block the equipment; while in this solution, the kitchen waste and kitchen organic matter are combined to form a mixed organic matter and fermented with biogas residue sludge (including kitchen sludge and kitchen organic sludge). The kitchen waste can not only provide organic matter, but also provide support for the mixed organic matter, avoiding the settlement and blockage of the mixed material in the equipment, and effectively improving the continuity of the mixed fermentation.

[0010] 2. And this solution effectively improves the mixing and homogenization effect of the mixed organic matter by adding a mixing unit, thereby effectively improving the fermentation efficiency and fermentation effect. Specifically, this solution sets a material pit to facilitate the preliminary mixing of fermentation materials from different sources, sets a mixer to further mix the preliminarily mixed materials, and sets a grab bucket and a guide arc plate to facilitate the transfer of the preliminarily mixed raw materials in the material pit to the mixer for full mixing, thereby effectively improving the fermentation effect of kitchen waste and kitchen organic matter; in addition, this solution sets an inclined guide arc plate to facilitate the mixed material to automatically slide into the mixer under the action of gravity, improving the transfer effect of the mixed material.

[0011] 3. In the mixed fermentation process of this solution, biogas residue sludge (including food waste sludge and kitchen waste sludge) can also be added as raw materials to facilitate the provision of the microorganisms required for fermentation in the mixed fermentation. Specifically, although there are also some microorganisms in food waste and kitchen waste organic matter, their quantity is limited. Adding biogas residue sludge in the mixed fermentation process can not only provide microorganisms for the mixed materials, but also improve the bonding force and fluidity of the mixed materials, avoiding the settlement of difficult-to-degrade or non-degradable impurities around the equipment after the organic matter degrades to form voids and blocking the equipment.

[0012] 4. By setting up a medium-temperature dry fermentation unit in this solution, it is convenient to carry out medium-temperature dry fermentation on the evenly mixed fermentation materials to obtain biogas energy and fermentation mixture, realizing the resource utilization of the organic matter in the fermentation materials and reducing resource waste. And by setting up a post-treatment unit after fermentation, it is convenient to carry out post-treatment on the fermentation mixture, thus realizing the full-line treatment of food waste and kitchen waste organic matter, reducing its harm to the environment, and being of great significance to maintaining the earth's environment.

[0013] Preferably, as an improvement, the transfer device includes a grab bucket and a guiding arc plate arranged obliquely. One end of the guiding arc plate extends into the mixer, and the guiding arc plate is made of a smooth metal fabric.

[0014] Technical effect: With the above settings in this solution, it is convenient to grab the mixed materials in the pit and slide them down along the guiding arc plate into the mixer for full mixing, thereby improving the fermentation efficiency and fermentation effect of the mixed materials.

[0015] Preferably, as an improvement, the driving mechanism includes a motor, a driving gear connected to the motor, and a driven gear sleeved outside the mixing cylinder, and the driving gear meshes with the driven gear.

[0016] Technical effect: With the above settings in this solution, it is convenient to drive the mixing cylinder to rotate to promote the full mixing of the mixed materials.

[0017] Preferably, as an improvement, the aperture of the feeding end of the mixing cylinder is larger than that of the discharging end, and the inclined taper of the mixing cylinder is 2 - 4°, preferably 2°.

[0018] Technical effect: With the above settings in this solution, it is convenient for the mixed materials to be mixed while rotating with the cylinder and transported forward at the same time. By limiting the inclined taper of the mixing cylinder, it can effectively avoid the materials being transported too fast and being unevenly mixed.

[0019] Preferably, as an improvement, the pressure angle ɑ of the spiral blades is 15 - 20° and the height is 45 - 55mm.

[0020] Technical effect: By defining the pressure angle ɑ of the spiral blade, that is, the inclination angle between the spiral direction of the spiral blade and the radial plane of the mixing cylinder is 20°, it is convenient to push the mixed material forward during the rotation of the mixing cylinder, avoiding the material from rolling in place, thereby accelerating the discharging speed of the mixed material.

[0021] Preferably, as an improvement, along the direction from the feed end to the discharge end, a conveying section is further provided at the rear end of the mixing and dispersing section. A continuous spiral blade is provided in the conveying section, and the length of the conveying section is less than or equal to one-third of the length of the mixing cylinder; the shape of the spiral blade is trapezoidal, and the edge chamfer of the trapezoid is arc-shaped.

[0022] Technical effect: By setting two types of spiral blades (continuous spiral blades and segmented spiral blades) in this solution, the continuity and stability of the mixing of the mixed material can be effectively improved. Defining the length of the conveying section facilitates shortening the settlement distance of heavy substances such as sand and gravel in the mixed material during the conveying process, reducing their settlement and sticking to the inner wall of the mixing cylinder and reducing the mixing effect. The top of the arc-shaped spiral blade is not easy to entangle and hang the material and is not easy to stick, and when the material falls, it has a certain dispersing effect.

[0023] Preferably, as an improvement, a pusher block is provided near the feed end of the spiral blade along the spiral direction of the spiral blade. The long axis of the pusher block is parallel to the axial direction of the mixing cylinder; the pusher block divides the space between adjacent spiral blades into a sliding material mixing gap and a pusher conveying gap; the shapes of the spiral blade and the pusher block are both trapezoidal, and the edge chamfer of the trapezoid is arc-shaped.

[0024] Technical effect: With the above settings in this solution, it is convenient to fully mix the mixed material while transporting the mixed material forward. Specifically, a pusher groove is formed between the pusher block and the spiral blade. A pusher conveying gap for pushing the material forward is formed between the pusher block and the adjacent spiral blade. A sliding material mixing gap is formed between the end of the pusher block far from the spiral blade and the adjacent spiral blade. When the material is pushed to the upper half of the mixing cylinder by the rotation of the mixing cylinder, the material slides or rolls back to the lower half of the mixing cylinder under the action of gravity and mixes with other materials again, and then continues to be transported forward under the push of the pusher block and the spiral blade (the mixed material is located in the pusher groove and the pusher conveying gap), realizing the full mixing and forward transportation of the material in the mixing cylinder.

[0025] Preferably, as an improvement, the medium-temperature dry fermentation unit includes a fermentation tank. The top of the fermentation tank is connected to a biogas collection device, and a discharge port is provided at the bottom. The discharge port is connected to a bottom discharge screw. The outlet of the bottom discharge screw is connected to a return pipe, and the other end of the return pipe is connected to the feed end of the mixer; a mixing and conveying pipe is connected between the discharge end of the mixing cylinder and the fermentation tank, and a feed plunger pump is provided on the mixing and conveying pipe.

[0026] Technical effect: With the above settings in this solution, it is convenient for the mixed materials to enter the fermentation tank for mixed fermentation, and a part of the mixed fermented materials is refluxed to the mixer, enabling the high-concentration microorganisms in the fermentation mixture to enter the mixed fermentation stage again. This effectively replenishes the microbial supply of the mixed materials during the fermentation stage and enhances the bonding force of the mixed materials, thereby enabling efficient and continuous mixed fermentation.

[0027] Preferably, as an improvement, the post-treatment unit includes an extruder, which is provided with a mixed fermented material inlet, a sewage outlet, and an extrusion residue outlet. The mixed fermented material inlet is connected to the bottom discharge screw, the sewage outlet is connected to a sewage tank, and the extrusion residue outlet is connected to an extrusion residue box.

[0028] Technical effect: With the above settings in this solution, it is convenient for the post-treatment of the materials after fermentation. Specifically, the other part of the fermented mixture that is not refluxed is separated into sewage and extrusion residue (specifically biogas sludge) by the extruder, which facilitates subsequent classification treatment and realizes the complete treatment of food waste and kitchen waste organic matter.

[0029] Preferably, as an improvement, the feeding end of the material pit is also connected to a food waste box, a kitchen waste organic matter temporary storage box, and a biogas residue and sludge box.

[0030] Technical effect: With the above settings in this solution, it is convenient to preliminarily mix food waste, kitchen waste organic matter, and biogas residue and sludge in the material pit. The biogas residue and sludge can also be the biogas sludge obtained from the anaerobic fermentation of food waste, effectively realizing the coordinated treatment of food waste and kitchen waste, and taking into account the unity between enhancing the economic benefits of organic matter recovery and the environmental benefits of waste treatment. Brief Description of the Drawings

[0031] Figure 1 It is a schematic structural diagram of the medium-temperature dry fermentation system for food waste and kitchen waste organic matter in Embodiment 1 of the present invention.

[0032] Figure 2 It is a schematic structural diagram of the anti-winding mixer in Embodiment 1 of the present invention.

[0033] Figure 3 It is a schematic structural diagram of the mixing drum in Embodiment 1 of the present invention.

[0034] Figure 4 is Figure 2 a schematic diagram of the shape of the spiral blade.

[0035] Figure 5 It is a schematic structural diagram of the multi-source organic solid waste collaborative treatment system in Embodiment 3 of the present invention. Detailed Description of the Invention

[0036] The following is a further detailed description through specific embodiments:

[0037] The markings in the attached drawings of the specification include: base 1, mixing cylinder 2, feed end 21, discharge end 22, motor 3, driving gear 31, driven gear 32, spiral blade 4, pusher block 5, pusher conveying gap 51, and sliding material mixing gap 52.

[0038] Example 1

[0039] Basically as shown in the attached Figure 1 figures: A medium-temperature dry fermentation system for kitchen waste and kitchen organic matter includes a mixing unit, a medium-temperature dry fermentation unit, and a post-treatment unit connected by pipelines.

[0040] The mixing unit includes a connected material pit, a transfer device, and a mixer. The feed end of the material pit is also connected to a kitchen waste box, a kitchen organic matter temporary storage box, and a biogas residue and sludge box. As a reference, in this embodiment, the biogas residue and sludge box is specifically a kitchen sludge box for transporting the kitchen sludge obtained from the anaerobic fermentation of kitchen waste. The transfer device includes a grab bucket and an inclined guide plate. One end of the guide plate extends into the mixer, and the other end is fixed to the ground through a bracket. The grab bucket is a hoisting tool in the prior art for grasping and discharging bulk materials by the opening and closing of two combined buckets or multiple jaw plates on the left and right. In this solution, the kitchen waste and kitchen organic matter are first transported to the material pit to form a mixed material, and then transported to the mixer for full mixing. As a reference, the guide plate is made of a smooth metal material, such as a smooth aluminum alloy material. In this solution, the mixed material in the material pit is grabbed by the grab bucket and placed on the guide plate, and then slides into the mixer obliquely under the action of gravity to complete the full mixing of the mixed material (including kitchen waste, kitchen organic matter, and kitchen sludge).

[0041] As Figure 2 shown, the mixer includes a base 1, a mixing cylinder 2 rotatably connected to the base 1, and a driving mechanism for driving the rotation of the mixing cylinder 2. The driving mechanism includes a motor 3, a driving gear 31 connected to the motor 3, and a driven gear 32 sleeved outside the mixing cylinder 2. The driving gear 31 meshes with the driven gear 32.

[0042] As Figure 3 shown, the two ends of the mixing cylinder 2 are respectively a feed end 21 and a discharge end 22. The mixing cylinder 2 is inclined, and the feed end 21 is higher than the discharge end 22; the aperture of the feed end 21 of the mixing cylinder 2 is larger than that of the discharge end 22. As a reference, the inclination taper of the mixing cylinder 2 is 2 - 4°, preferably 2°, to avoid the material from being transported too fast. A mixing and dispersing section is provided inside the mixing cylinder 2, and segmented spiral blades 4 are provided in the mixing and dispersing section. As an improvement, at least two groups of segmented spiral blades 4 with different pitches are provided in the mixing and dispersing section to facilitate the dispersion and separation of the material during mixing and prevent it from winding into a group and blocking the equipment.

[0043] A pusher block 5 is provided near the feed end 21 of the spiral blade 4 along the spiral direction of the spiral blade 4. The long axis of the pusher block 5 is parallel to the axial direction of the mixing cylinder 2. A pusher groove (not shown in the figure) is formed between the pusher block 5 and the spiral blade 4. The pusher block 5 divides the space between adjacent spiral blades 4 into a sliding material mixing gap 52 and a pusher conveying gap 51. Among them, a pusher conveying gap 51 for pushing the material forward is formed between the pusher block 5 and the adjacent spiral blade 4, and a sliding material mixing gap 52 is formed between the end of the pusher block 5 far from the spiral blade 4 and the adjacent spiral blade 4. When the material rotates with the mixing cylinder 2 to the upper half of the mixing cylinder 2, the material slides or rolls back along the sliding material mixing gap 52 under the action of gravity to the lower half of the mixing cylinder 2 and is mixed with other materials again, and then continues to be conveyed forward under the push of the pusher block 5 and the spiral blade 4, realizing the full mixing of the material in the mixing cylinder 2. As a reference, the pusher block 5 is 300 mm long and the sliding material mixing gap 52 is 200 mm long. This gap makes it easier for the material to be mixed, avoiding the situation that all the materials are piled up in the pusher groove and directly discharged with the rotation of the mixing cylinder 2, making it difficult to be evenly mixed.

[0044] As Figure 4 shown, the shapes of both the spiral blade 4 and the pusher block 5 are inclined "trapezoids", and the edges of the "trapezoids" are chamfered into arcs. Because when the material has some viscosity and is easy to stick, the top of the arc-shaped spiral blade 4 is not easy to wind and hang the material and is not easy to stick. And when the material falls, it has a certain effect of breaking up. The pressure angle ɑ of the spiral blade 4 is 15 - 20° and the height is 45 - 55 mm, which is convenient for breaking up and pushing the mixed material forward during the rotation of the mixing cylinder 2, improving the conveying speed and avoiding the mixed material rolling in place.

[0045] As Figure 1 shown, a mixing and conveying pipe is connected between the discharge end of the mixing cylinder and the medium-temperature dry fermentation unit. An inlet plunger pump is provided on the mixing and conveying pipe, which is convenient for pumping the mixed material in the mixer into the fermentation tank.

[0046] The medium-temperature dry fermentation unit includes a fermentation tank, and the fermentation tank is a vertical anaerobic fermentation tank or a horizontal anaerobic fermentation tank; as a reference, the fermentation tank in this solution is specifically a vertical anaerobic fermentation tank. The top of the fermentation tank is connected to a biogas collection device, and the bottom is provided with a discharge port. The discharge port is connected to a bottom discharge screw. The outlet of the bottom discharge screw is connected to a return pipe, and the other end of the discharge of the return pipe is connected to the feed end 21 of the mixer.

[0047] The post-treatment unit includes an extruder. As a reference, the extruder is an extruder with a screen. The extruder is provided with a mixed fermentation product inlet, a sewage outlet and an extrusion residue outlet. The mixed fermentation product inlet is connected to the bottom discharge screw. As a reference, a discharge plunger pump is provided on the connecting pipe between the extruder and the bottom discharge screw; the sewage outlet is connected to a sewage tank, and the extrusion residue outlet is connected to an extrusion residue box.

[0048] The mixed kitchen waste, kitchen organic matter and kitchen sludge initially form a mixed material in the material pit, and then are grabbed by a grab bucket and placed at one end of the arc-shaped guide plate, and then slide obliquely into the mixer along the arc-shaped guide plate. During the rotation of the mixing cylinder 2 in the mixing cylinder 2, the material is intermittently scattered and conveyed by the spiral blade 4 and the pushing block 5 in a cycle, so as to realize the full mixing and forward conveying of the material. Specifically, when the material is pushed to the upper half of the mixing cylinder 2 along with the rotation of the mixing cylinder 2, the material slides or rolls back to the lower half of the mixing cylinder 2 by itself under the action of gravity through the sliding material mixing gap 52 and is mixed with other materials again, and then continues to be conveyed forward under the pushing of the pushing block 5 and the spiral blade 4 (the mixed material is located in the pushing groove and the pushing conveying gap 51), realizing the full mixing and forward conveying of the material in the mixing cylinder 2.

[0049] The mixed material is pumped into the fermentation tank under the action of the feed plunger pump. Specifically, the mass ratio of kitchen waste, kitchen sludge and kitchen organic matter in the mixed material is 1-3:1-3:10, the fermentation temperature is 41±3°C, the hydraulic retention time HRT is 20-35d, biogas and a fermentation mixture are obtained by fermentation, and 30-50% of the fermentation mixture is refluxed to the mixer, and the remaining part enters the extruder and is extruded into sewage and extruded residue (i.e., biogas sludge), completing the mixed fermentation of kitchen waste and kitchen organic matter.

[0050] Example 2

[0051] The difference between this example and Example 1 is that: along the direction from the feed end 21 to the discharge end 22, a conveying section is also provided at the rear end of the mixing and scattering section, and a continuous spiral blade 4 is provided in the conveying section, and the length of the conveying section is less than or equal to one-third of the length of the mixing cylinder 2.

[0052] In this example, by setting two kinds of spiral blades 4 (continuous spiral blade 4 and segmented spiral blade 4), the continuity and stability of the mixing of the mixed material can be effectively improved. By limiting the length of the conveying section, it is convenient to shorten the sedimentation distance of heavy substances such as sand and gravel in the mixed material during the conveying process, and reduce the sedimentation and adhesion to the inner wall of the mixing cylinder 2 and reduce the mixing effect. The top of the arc-shaped spiral blade 4 is not easy to entangle and hang the material, is not easy to stick, and has a certain scattering effect when the material falls.

[0053] Example 3

[0054] This solution also provides a multi-source organic solid waste collaborative treatment system, including the medium-temperature dry fermentation system for kitchen waste and kitchen organic matter in Example 1, as Figure 5 shown, a kitchen waste pretreatment unit is also connected in front of the kitchen waste bin and the kitchen sludge bin, and a kitchen organic matter pretreatment unit is connected in front of the kitchen organic matter temporary storage bin, respectively treating kitchen waste into kitchen waste and kitchen sludge, and treating kitchen organic waste into kitchen organic matter, which is convenient for subsequent mixing and medium-temperature dry fermentation.

[0055] The kitchen waste pretreatment unit includes a sorting machine, a pulping machine, a impurity removing machine, an oil removing machine, an anaerobic fermentation tank and a dehydrator which are connected in sequence through pipelines; the outlets of the sorting machine and the pulping machine are also connected to a washing and squeezing device, the washing and squeezing device is connected to a coarse material impurity box, and the outlet of the impurity removing machine is also connected to a kitchen waste residue box; the outlet of the oil removing machine is also connected to a swill oil temporary storage box, and the outlet of the dehydrator is respectively connected to a sewage treatment device and a kitchen waste sludge box; both the kitchen waste residue box and the kitchen waste sludge box are connected to a material pit.

[0056] The kitchen waste pretreatment unit includes a crusher, a magnetic separator, a disc screen, a drum screen and a crusher which are connected in sequence, and the magnetic separator is also connected to a magnetic material slag box; both the disc screen and the drum screen are connected to an impurity box to collect coarse slag; another outlet of the crusher is connected to a kitchen waste organic matter temporary storage box, and the kitchen waste organic matter temporary storage box is connected to the material pit. Kitchen waste organic matter is obtained and preliminarily mixed with kitchen waste organic matter, kitchen waste residue and kitchen waste sludge in the material pit.

[0057] The sufficient mixing of the subsequent materials is completed in the above-mentioned mixer, the mixed fermentation is completed in the fermentation tank, the biogas of the mixed fermentation product is collected separately, and the fermentation mixture is processed in the above-mentioned post-treatment unit.

[0058] The above are only embodiments of the present invention, and common general technical knowledge such as specific technical solutions and / or characteristics known in the solutions are not described in detail here. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several deformations and improvements can be made, and these should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent. The protection scope required by this application should be subject to the content of its claims, and the specific implementation manners and the like recorded in the specification can be used to interpret the content of the claims.

Claims

1. A mesophilic dry fermentation system for kitchen waste and kitchen organic matter, characterized in that: It includes a mixing unit, a medium-temperature dry fermentation unit and a post-treatment unit connected by pipelines. The mixing unit includes a material pit, a transfer device and a mixer connected in sequence; the mixer includes a base, a mixing drum rotatably connected to the base, and a driving mechanism for driving the mixing drum to rotate. The two ends of the mixing drum are respectively a feed end and a discharge end. The mixing drum is inclined, with the feed end higher than the discharge end. A mixing and dispersing section is arranged inside the mixing drum, and segmented spiral blades are arranged in the mixing and dispersing section.

2. The mesophilic dry fermentation system for kitchen waste and kitchen organic matter according to claim 1, wherein: The transfer device includes a grab bucket and an inclined guide arc plate. One end of the guide arc plate extends into the mixer, and the guide arc plate is made of smooth metal fabric.

3. The mesophilic dry fermentation system for kitchen waste residues and kitchen waste organic matter according to claim 1, wherein: The driving mechanism includes a motor, a driving gear connected to the motor, and a driven gear sleeved outside the mixing drum. The driving gear meshes with the driven gear.

4. The mesophilic dry fermentation system for kitchen waste and kitchen organic matter according to claim 1, characterized in that: The aperture of the feed end of the mixing drum is larger than that of the discharge end, and the inclination taper of the mixing drum is 2 - 4°.

5. The mesophilic dry fermentation system for kitchen waste and kitchen organic matter according to claim 1, characterized in that: The pressure angle ɑ of the spiral blades is 15 - 20°, and the height is 45 - 55 mm.

6. The mesophilic dry fermentation system for kitchen waste and kitchen organic matter according to claim 1, characterized in that: In the direction from the feed end to the discharge end, a conveying section is also arranged at the rear end of the mixing and dispersing section. Continuous spiral blades are arranged in the conveying section, and the length of the conveying section is less than or equal to one-third of the length of the mixing drum; the shape of the spiral blades is trapezoidal, and the edges of the trapezoid are chamfered into an arc shape.

7. The mesophilic dry fermentation system for kitchen waste and kitchen organic matter according to claim 1, characterized in that: A pushing block is arranged along the spiral direction of the spiral blade near the feed end of the spiral blade. The long axis of the pushing block is parallel to the axial direction of the mixing drum; the pushing block divides the space between adjacent spiral blades into a sliding material mixing gap and a pushing material conveying gap; the shapes of the spiral blades and the pushing block are both trapezoidal, and the edges of the trapezoid are chamfered into an arc shape.

8. The mesophilic dry fermentation system for kitchen waste and kitchen organic matter according to claim 1, characterized in that: The medium-temperature dry fermentation unit includes a fermentation tank. The top of the fermentation tank is connected to a biogas collection device, and a discharge port is arranged at the bottom. The discharge port is connected to a bottom discharge screw. The outlet of the bottom discharge screw is connected to a return pipe, and the other end of the return pipe is connected to the feed end of the mixer; a mixing and conveying pipe is connected between the discharge end of the mixing drum and the fermentation tank, and a feed plunger pump is arranged on the mixing and conveying pipe.

9. The mesophilic dry fermentation system for kitchen waste and kitchen organic matter according to claim 8, wherein: The post-treatment unit includes an extruder. The extruder is provided with a mixed fermentation product inlet, a sewage outlet and an extrusion residue outlet. The mixed fermentation product inlet is connected to the bottom discharge screw, the sewage outlet is connected to a sewage tank, and the extrusion residue outlet is connected to an extrusion residue box.

10. The mesophilic dry fermentation system for kitchen waste and kitchen organic matter according to any one of claims 1 to 9, characterized in that: The feed end of the material pit is also connected to a kitchen waste bin, a kitchen organic matter temporary storage bin and a biogas residue and sludge bin.

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