An integrated device for desanding and desludging of kitchen pulp

Abstract

This utility model relates to an integrated device for removing slag and sand from kitchen slurry, comprising a coarse sand removal unit for removing scum and coarse sand from the slurry and a fine sand removal unit for removing fine sand from the slurry. The coarse sand removal unit includes a sand removal tank, a slag removal mechanism, a primary aeration pipe, and a primary screw conveyor. The sand removal tank has a scum zone above the vortex zone, which is connected to a scum collection tank. The scum removal mechanism includes a scum collection tank and a chain scraper assembly. The fine sand removal unit includes a fine sand removal tank, a secondary aeration pipe, and a secondary screw conveyor. The fine sand removal tank includes a circular tank body and a central cylinder. Multiple guide plates with staggered heights and spirally downward inclined are provided between the inner wall of the tank and the outer wall of the central cylinder. This utility model has a reasonable structure, which can improve the efficiency of slag and sand removal, effectively reduce equipment blockage and wear, and has good equipment operation stability, solving the problem of low separation efficiency caused by large changes in slurry concentration.

Description

Technical Field

[0001] In food waste treatment technology, the general approach is "pretreatment + anaerobic digestion". The slurry after pretreatment of food waste is characterized by high viscosity, high organic matter content, and the presence of grease and sand. Therefore, the pretreatment of food waste requires solid-liquid separation technology, that is, separating liquids such as water, grease, and organic matter from solid waste residue, and then treating the separated liquids and solids separately. Background Technology

[0002] Currently, in large-scale food waste treatment, after sorting and crushing, the food waste slurry passes through a sand and slag removal device and then enters a three-phase oil extractor for oil-water separation. To reduce the wear of heavy sand on subsequent equipment, sand removal is performed before oil extraction. However, the concentration of the slurry after food waste sorting varies, resulting in significant differences in separation efficiency. Traditional sand removal devices typically use sedimentation tanks for sand-water separation, relying on gravity settling. However, sedimentation tanks are mainly designed for separating sand particles from industrial or municipal wastewater. When dealing with the complex characteristics of food waste slurry, such as high oil content and viscosity, their practical application is significantly limited.

[0003] Existing sand removal devices for kitchen slurry employ a cyclone separator. Water enters the device tangentially, where a spiral blade generates intense rotation. Lighter sand and water have different densities; under the combined effects of centrifugal force, centripetal force, buoyancy, and fluid drag, the less dense water rises and is discharged from the outlet, while the denser sand particles are discharged from the drain at the bottom of the device. However, in viscous kitchen slurry, sand particles are easily encapsulated by organic matter, forming sand-organic complexes, significantly reducing settling velocity. Furthermore, during operation in kitchen slurry, sand particles may adhere and remain within the spiral channel, failing to be effectively discharged, resulting in insufficient sand separation efficiency. Additionally, fibers, grease, and debris in the kitchen slurry easily adhere to the surface of the spiral blades or the separator filter screen. The mixture of sand particles and organic matter accelerates blade wear, potentially leading to equipment downtime and requiring irregular maintenance. Therefore, clogging and wear are significant problems with the equipment. For high-viscosity kitchen waste slurry, it is usually necessary to increase the aeration intensity or the screw speed, which will lead to a significant increase in equipment energy consumption. Especially when the slurry concentration fluctuates, the lack of dynamic adjustment function results in large variations in separation efficiency and unstable treatment effect. Summary of the Invention

[0004] The purpose of this invention is to provide an integrated device for removing slag and sand from kitchen slurry, which has a reasonable structure, reduces the impact of slurry concentration changes on separation efficiency, improves slag and sand removal efficiency, reduces energy consumption, and enhances equipment operational stability.

[0005] The technical solution of this utility model to achieve the above-mentioned objective is: an integrated device for removing slag and sand from kitchen slurry, characterized in that: it includes a coarse sand removal unit for removing slag and coarse sand from the slurry and a fine sand removal unit for removing fine sand from the slurry.

[0006] The coarse sand separation and desanding unit includes a sand separation tank, a slag removal mechanism, a primary aeration pipe, and a primary screw conveyor. The sand separation tank includes an inverted conical coarse sand settling zone and an upper cylindrical vortex zone. The sand separation tank has a tangential primary water inlet in the vortex zone and a scum zone above the vortex zone, which is connected to a slag collection tank. The sand separation tank has a primary water outlet above the coarse sand settling zone and a primary aeration pipe with multiple primary aeration holes below the coarse sand settling zone. The primary aeration pipe is used to agitate the slurry and wash the settling sand. The sand outlet at the bottom of the sand separation tank is connected to the feed inlet of the primary screw conveyor, and a primary electric gate is installed at the sand outlet of the sand separation tank.

[0007] The slag removal mechanism includes a slag collection tank and a chain plate scraper assembly. The slag collection tank is located outside the sand desanding coarse separator and is opposite to the primary water inlet. The two end plates of the slag collection tank are fixedly connected to the sand desanding coarse separator. The chain plate scraper assembly is installed on the slag collection tank. The scraper plates on the chain plate scraper assembly scrape the floating slag in the upper part of the vortex zone from the floating slag zone to the slag collection tank. The bottom of the slag collection tank is provided with a slag discharge port.

[0008] The sand removal and refining unit includes a sand removal and refining tank, a secondary aeration pipe, and a secondary screw conveyor. The sand removal and refining tank includes a circular tank body and a central cylinder. The upper part of the sand removal and refining tank is provided with a secondary water inlet and a clean water outlet. The secondary water inlet is connected to the primary water outlet through a pipeline. Multiple guide plates with staggered heights and spiral downward inclination are provided between the inner wall of the tank and the outer wall of the central cylinder. The guide plates are used to guide the slurry downward and provide gravity buffering. The top guide plate is located below the secondary water inlet. The bottom of the central cylinder is open and the top is provided with a top plate. The upper part of the central cylinder is connected to the clean water outlet. The sand removal and refining tank is provided with a secondary aeration pipe with multiple second aeration holes at the bottom. The secondary aeration pipe is used to agitate the slurry and wash the fine sand. The sand outlet at the bottom of the sand removal and refining tank is connected to the feed inlet of the secondary screw conveyor, and a secondary electric gate is installed at the sand outlet of the sand removal and refining tank.

[0009] This invention combines a cyclone coarse sand removal unit for removing scum and coarse sand from slurry with a fine sand removal unit for removing fine sand from slurry. The cyclone coarse sand removal unit scrapes off the scum in the cyclone zone of the slurry entering the coarse sand removal tank, removing larger particles or fibrous materials from the scum in time. Then, the fine sand removal unit continues to treat the wastewater for sand removal. The slurry is treated in two stages, resulting in a uniform slurry distribution. This not only reduces the phenomenon of short sand settling paths but also reduces the adhesion of fibers, grease, and organic debris, improving the impurity removal efficiency and reducing pipeline blockage. This invention utilizes high-speed cyclone separation in a coarse sand removal tank to remove sand from kitchen slurry, effectively removing coarse sand larger than 500μm with a removal rate exceeding 95%. The slurry, after coarse sand removal, is then fed into a fine sand removal tank via a secondary inlet. Further fine sand (50-500μm) is removed through multiple staggered guide plates between the fine sand removal tank and the central cylinder. This spiral guides the slurry along a pre-defined path under gravity before discharge through the central cylinder, extending the settling path and processing time for fine sand, reducing sand escape, and improving the separation efficiency between fine sand and organic matter. This invention effectively solves the problem of low separation efficiency caused by large variations in slurry concentration by using a two-stage synergistic process of cyclone coarse sand removal and fine sand removal units to separate sand and organic matter. This invention features a primary aeration pipe within the coarse sand separation tank, which effectively removes surface organic matter from impacted sand and gravel clumps. Simultaneously, a secondary aeration pipe within the fine sand separation tank allows microbubbles to penetrate the gaps between sand particles, deeply cleaning the sand and gravel surface. This achieves the dual effects of forceful removal and fine sand removal, reducing the loss of organic matter and grease, mitigating the impact of slurry concentration variations on separation efficiency, and improving the separation efficiency of sand and organic matter. The invention also boasts a rational structure, effectively reducing equipment clogging and wear, and enhancing operational stability. Attached Figure Description

[0010] The embodiments of this utility model will now be described in further detail with reference to the accompanying drawings.

[0011] Figure 1 This is a schematic diagram of the structure of an integrated device for removing slag and sand from kitchen slurry according to this utility model.

[0012] Figure 2 This is a structural schematic diagram of the sand removal and coarse separation tank and slag collection pool of this utility model.

[0013] Figure 3 yes Figure 1 A magnified structural diagram at point I.

[0014] Figure 4 yes Figure 1 Enlarged structural diagram at point II.

[0015] Wherein: 1—Sand removal and coarse separation tank, 1-1—Primary inlet, 1-2—Swirl zone, 1-3—Scum zone, 1-4—Coarse sand settling zone, 1-5—Primary outlet, 2—Chain plate scraper assembly, 2-1—Scraper plate, 2-11—Scum plate seat, 2-12—Scraper, 2-2—Passive chain shaft, 2-3—Chain, 2-4—Drive chain shaft, 2-5—Drive chain, 2-6—Motor, 3—Scum collection tank, 3-1 —Slag discharge port, 3-2—Bearing seat, 4—Primary aeration pipe, 5—Primary electric gate, 6—Primary screw conveyor, 7—Sand removal and purification tank, 7-1—Secondary water inlet, 7-2—Guide plate, 7-3—Clear water outlet, 7-4—Central cylinder, 7-5—Sand baffle, 7-51—Secondary guide rib, 7-6—Conical tank bottom, 8—Secondary aeration pipe, 9—Secondary electric gate, 10—Secondary screw conveyor. Specific Implementation

[0016] See Figure 1 As shown, this utility model discloses an integrated device for removing slag and sand from kitchen slurry, including a coarse sand removal unit for removing slag and coarse sand from the slurry and a fine sand removal unit for removing fine sand from the slurry.

[0017] See Figure 1 , 2 As shown, the coarse sand separation and desanding unit of this utility model includes a sand separation tank 1, a slag removal mechanism, a primary aeration pipe 4, and a primary screw conveyor 6. The sand separation tank 1 includes an inverted conical coarse sand settling zone 1-4 and an upper cylindrical swirl zone 1-2. The sand separation tank 1 is provided with a tangential primary water inlet 1-1 on the swirl zone 1-2. Therefore, the kitchen slurry enters the sand separation tank 1 tangentially through the primary water inlet 1-1. Swirl flow zones 1-2 form a swirling flow, which, under gravity, enters the coarse sand settling zones 1-4. Under the action of the inverted conical guide wall, rapid separation of large sand particles is achieved. In this invention, the included angle of the tank wall in the coarse sand settling zones 1-4 of the coarse sand separation tank 1 is 60±5°. If the included angle of the inverted conical guide wall of the coarse sand separation tank 1 is 60°, the kitchen slurry enters the coarse sand separation tank 1 and swirls at a high flow rate of 1.5-2.0 m / s, rapidly removing coarse sand >500μm with a removal rate >95%. See [link / reference]. Figure 1 , 2 As shown, the sand removal and coarse separation tank 1 of this utility model is provided with a scum zone 1-3 above the vortex zone 1-2. The scum zone 1-3 is connected to the scum collection tank 3. Therefore, larger particles or fibrous materials in the kitchen slurry entering the sand removal and coarse separation tank 1 are removed to the scum collection tank 3 in a timely manner, reducing equipment and pipeline blockage and improving the impurity removal efficiency.

[0018] See Figure 1As shown, the coarse sand separator 1 of this utility model has a primary outlet 1-5 above the coarse sand settling zone 1-4. The slurry after removing scum and coarse sand is added to the fine sand separator 7 through the primary outlet 1-5 for secondary treatment. See... Figure 1 As shown, the sand separation tank 1 of this utility model is provided with a primary aeration pipe 4 with multiple first aeration holes at the lower part of the coarse sand settling zone 1-4. The primary aeration pipe 4 is connected to the air duct. The primary aeration pipe 4 is made of oleophobic material. The primary aeration pipe 4 is used to disturb the slurry and wash the settling sand. Through intermittent aeration by the primary aeration pipe 4, the aggregated state of sand and food residue in the slurry after settling is impacted, and organic matter on the surface of the sand and gravel clumps is peeled off, which can improve the separation efficiency of sand and gravel and organic matter. At the same time, the slurry is continuously disturbed to prevent sand and gravel from caking and smoothly discharge the settling sand at the bottom to the primary screw conveyor 6. The primary aeration pipe 4 of this utility model is arranged in a ring inside the sand removal and coarse separation tank 1. The first aeration holes on the primary aeration pipe 4 are arranged along the circumference and axial direction of the pipe wall, and the diameter of the first aeration holes is between 3 and 5 mm. If the diameter of the first aeration hole is 5 mm, and the aeration is interrupted for 2 minutes and then stopped for 1 minute, intermittent aeration is formed and large bubbles are generated, which can violently peel off the organic matter on the sand and gravel. It can also continuously aerate and generate large bubbles to prevent the sand and gravel from caking.

[0019] See Figure 1 As shown, the sand outlet at the bottom of the sand desanding tank 1 of this utility model is connected to the feed inlet of the primary screw conveyor 6. A primary electric gate 5 is installed at the sand outlet of the sand desanding tank 1. The primary electric gate 5 controls the sand discharge, and the primary screw conveyor 6 discharges the sand and gravel. The screw conveyor 6 of this utility model is an existing shaftless screw conveyor. The outer diameter of the shaftless screw blades remains unchanged, and the pitch of the front and middle parts of the shaftless screw blades is the same. The pitch of the screw blade compression section is 1.5 to 2.5 times the pitch of the front and middle screw blades. For example, if the pitch of the screw blade compression section is twice the pitch of the front and middle screw blades, the sand and gravel are compressed by the screw blades with variable pitch, and the remaining organic matter on the surface is peeled off, further separating the sand and gravel from the organic matter, and then the sand and gravel are discharged.

[0020] See Figures 1 to 4As shown, the slag removal mechanism of this utility model includes a slag collection tank 3 and a chain plate scraper assembly 2. The slag collection tank 3 is located outside the sand removal coarse separator tank 1 and faces away from the water inlet. The two end plates of the slag collection tank 3 are fixedly connected to the sand removal coarse separator tank 1. The top of the sand removal coarse separator tank 1 is open and communicates with the slag collection tank 3. Therefore, the scum area 1-3 at the top of the sand removal coarse separator tank 1 communicates with the slag collection tank 3. This utility model may also provide a semi-circular transverse partition plate at the top of the sand removal coarse separator tank 1. Furthermore, the sand removal and coarse separation tank 1 has a notch on the upper part of the horizontal partition plate and is connected to the slag collection tank 3. The slag collection tank 3 is equipped with a chain plate scraper assembly 2. The scraper plate 2-1 on the chain plate scraper assembly 2 scrapes the scum on the slurry from the scum area 1-3 into the slag collection tank 3, preventing the scum from flowing out from the primary outlet 1-5. The bottom of the slag collection tank 3 is provided with a slag discharge port 3-1. After the scum is collected in the slag collection tank 3, it is discharged through the slag discharge port 3-1 and the scum is treated separately.

[0021] See Figures 1 to 4 As shown, the chain plate scraper assembly 2 of this utility model includes a motor 2-6, a drive chain shaft 2-4, a driven chain shaft 2-2, multiple scraper plates 2-1, and two chains 2-3. The drive chain shaft 2-4 and the driven chain shaft 2-2 are mounted on the slag collection tank 3 via bearing seats 3-2. The bearing seats 3-2 are mounted on the front and rear sides of the end plates of the slag collection tank 3. The drive chain shaft 2-4 and the driven chain shaft 2-2 are mounted on their respective bearing seats 3-2 via bearings. The drive chain shaft 2-4 has drive sprockets at both ends, and the driven chain shaft 2-2 has driven sprockets at both ends. The two chains 2-3 are correspondingly mounted on the drive sprockets and driven sprockets. The scraper plates 2-1 are mounted on the two chains 2-3 at both ends. The output side of the motor 2-6 mounted on the slag collection tank 3 is connected to the drive chain shaft 2-4. Figure 4 As shown, the output shaft of the motor 2-6 of this utility model is equipped with an upper sprocket, and the drive sprocket 2-4 is also equipped with a corresponding lower sprocket. The transmission chain 2-5 is installed on the upper and lower sprockets, transmitting the power output from the motor 2-6 to the drive sprocket 2-4 through the transmission chain 2-5. The motor 2-6 drives the drive sprocket on the drive sprocket 2-4 to drive the chain 2-3, which in turn drives the scraper 2-1 to scrape the scum into the scum collection tank 3. See Figure 2 , 3 As shown, the slag scraper 2-1 of this utility model includes two slag plate seats 2-11 and a scraper 2-12. The slag plate seats 2-11 are L-shaped and are installed on the corresponding chain 2-3. The two ends of the scraper 2-12 are installed on the slag plate seats 2-11 by fasteners.

[0022] See Figure 1As shown, the sand removal and refining unit of this utility model includes a sand removal and refining tank 7, a secondary aeration pipe 8, and a second screw conveyor. The sand removal and refining tank 7 includes a circular tank body and a central cylinder 7-4. The upper part of the sand removal and refining tank 7 is provided with a secondary water inlet 7-1 and a clean water outlet 7-3. The clean water outlet 7-3 is lower than the secondary water inlet 7-1. The secondary water inlet 7-1 is connected to the primary water outlet 1-5 via a pipeline. The wastewater after primary sand removal is added to the sand removal and refining tank 7 through the secondary water inlet 7-1 for further sand removal. The wastewater after sand removal is discharged through the clean water outlet 7-3 and enters the subsequent treatment process. See Figure 1 As shown, the inner wall of the tank and the outer wall of the central cylinder 7-4 of this utility model are provided with multiple guide plates 7-2 of staggered heights and spirally downward inclined. The guide plates 7-2 are used to guide the slurry downward and provide gravity buffering. The top guide plate 7-2 is located below the secondary water inlet 7-1. The bottom of the central cylinder 7-4 is open and the top is provided with a top plate. The upper part of the central cylinder 7-4 is connected to the clear water outlet 7-3. The water flow is forced to flow downward spirally through multiple guide plates 7-2. The staggered heights of the guide plates 7-2 can form a gravity buffer layer, prolonging the settling path and settling time of fine sand. The central cylinder 7-4 effectively avoids short flow. Through the two-stage sand removal treatment, the violent stripping and fine sand removal effects are achieved. It can meet the treatment of slurry of different concentrations and solve the problem of fine sand escape caused by the reduced settling time of the inverted conical vortex. The sand removal efficiency is stable and reliable.

[0023] See Figure 1 As shown, the diameter-to-height ratio of the sand removal and refining tank 7 of this utility model is between 1:1.20 and 1.5. For example, if the diameter-to-height ratio of the sand removal and refining tank 7 is 1:1.25, the sand removal and refining tank 7 removes fine sand of 50-500μm. The wastewater after sand removal enters the central cylinder 7-4 and is discharged through the clean water outlet 7-3. See... Figure 1 As shown in this invention, 4 to 8 guide plates 7-2 are evenly distributed around the sand removal and purification tank 7. For example, 5 guide plates 7-2 are evenly distributed around the sand removal and purification tank 7. The wastewater flows spirally downward under the guiding action of the guide plates 7-2. The downward inclination angle between the guide plates 7-2 and the horizontal plane is between 40±5°. For example, the downward inclination angle between the guide plates 7-2 and the horizontal plane is 40° to ensure guidance and swirling flow. The guide plates 7-2 have multiple first guide ribs on the bottom surface to form a concave-convex surface. The height of the first guide ribs is between 1 and 5 mm, and the distance between adjacent first guide ribs is between 50±10 mm. For example, the height of the first guide ribs is 2 mm and the spacing is 50 mm. After the water comes into contact with the guide ribs, the fine sand will move downward and settle.

[0024] See Figure 1As shown, the central cylinder 7-4 of this utility model has multiple sand-blocking plates 7-5 that slope downwards from the outside to the inside along the circumference and height direction. As the water flows upward, it gradually passes through the sand-blocking plates 7-5, further blocking fine sand. The lower part of the sand-blocking plate 7-5 has multiple guide ribs that form a concave-convex surface. The height of the second guide rib 7-51 is 1 to 5 mm, and the distance between adjacent second guide ribs 7-51 is between 50 ± 10 mm, which better prevents fine sand from escaping with the water flow when the treated water flows upward.

[0025] See Figure 1 As shown, the lower part of the sand removal and fine separation tank 7 of this utility model is provided with a secondary aeration pipe 8 with multiple second aeration holes. The secondary aeration pipe 8 is connected to a blower and is made of an oleophobic material. The secondary aeration pipe 8 is used to agitate the slurry and wash the fine sand. Continuous microbubbles penetrate the gaps between sand particles, and the residual organic matter and grease on the surface of the fine sand are stripped away by tension, thus achieving secondary fine sand removal. See Figure 2 As shown, the secondary aeration pipe 8 of this invention is arranged in a ring shape inside the sand removal and fine separation tank 7. The second aeration holes on the secondary aeration pipe 8 are arranged circumferentially and axially along the pipe wall, and the diameter of the second aeration holes is between 0.1 and 0.3 mm. For example, if the diameter of the second aeration hole is 0.2 mm, continuous air is supplied to the secondary aeration pipe 8, and the second aeration holes continuously aerate, allowing microbubbles to penetrate 50-500 μm sand particles to achieve fine sand removal and deep cleaning of the fine sand surface. See Figure 1 As shown, the sand outlet at the bottom of the sand removal and fine separation tank 7 of this utility model is connected to the feed inlet of the secondary screw conveyor 10. The secondary screw conveyor 10 is an existing shaftless screw blade conveyor. A secondary electric gate 9 is installed at the sand outlet of the sand removal and fine separation tank 7. The sand removal and fine separation tank 7 has a conical tank bottom 7-6, which settles the fine sand at the conical tank bottom 7-6, facilitating the discharge of the settled sand. The secondary electric gate 9 controls the sand discharge, and the secondary screw conveyor 10 discharges the fine sand.

Claims

1. An integrated device for removing slag and sand from kitchen slurry, characterized in that: It includes a coarse sand removal unit for removing scum and coarse sand from the slurry and a fine sand removal unit for removing fine sand from the slurry; The coarse sand separation and desanding unit includes a sand separation tank (1), a slag removal mechanism, a primary aeration pipe (4), and a primary screw conveyor (6). The sand separation tank (1) includes an inverted conical coarse sand settling zone (1-4) and an upper cylindrical swirl zone (1-2). The sand separation tank (1) has a tangential primary inlet (1-1) on the swirl zone (1-2). The sand separation tank (1) has a scum zone (1-3) above the swirl zone (1-2). The scum zone (1-3) is connected to the slag collection zone. The tank (3) is connected; the sand removal coarse separator (1) is provided with a primary outlet (1-5) at the upper part of the coarse sand settling area (1-4), and the sand removal coarse separator (1) is provided with a primary aeration pipe (4) with multiple first aeration holes at the lower part of the coarse sand settling area (1-4). The primary aeration pipe (4) is used to disturb the slurry and wash the settling sand; the sand outlet at the bottom of the sand removal coarse separator (1) is connected to the feed inlet of the primary screw conveyor (6), and a primary electric gate (5) is installed at the sand outlet of the sand removal coarse separator (1); The slag removal mechanism includes a slag collection tank (3) and a chain plate scraper assembly (2). The slag collection tank (3) is located outside the sand desanding coarse separator (1) and opposite to the first-stage inlet (1-1). The two end plates of the slag collection tank (3) are fixedly connected to the sand desanding coarse separator (1). The chain plate scraper assembly (2) is installed on the slag collection tank (3). The scraper plate (2-1) on the chain plate scraper assembly (2) scrapes the floating slag above the swirling zone (1-2) from the floating slag zone (1-3) into the slag collection tank (3). The bottom of the slag collection tank (3) is provided with a slag discharge port (3-1). The sand removal and refining unit includes a sand removal and refining tank (7), a secondary aeration pipe (8), and a secondary screw conveyor (10). The sand removal and refining tank (7) includes a circular tank body and a central cylinder (7-4). The upper part of the sand removal and refining tank (7) is provided with a secondary water inlet (7-1) and a clean water outlet (7-3). The secondary water inlet (7-1) is connected to the primary water outlet (1-5) through a pipeline. Between the inner wall of the tank and the outer wall of the central cylinder (7-4), there are multiple guide plates (7-2) with staggered heights and spirally inclined downwards. The guide plates (7-2) are used to guide the slurry downwards and... The gravity buffer is used, and the top guide plate (7-2) is located below the secondary water inlet (7-1). The bottom of the central cylinder (7-4) is open and the top is equipped with a top plate. The upper part of the central cylinder (7-4) is connected to the clean water outlet (7-3). The sand removal and fine separation tank (7) is equipped with a secondary aeration pipe (8) with multiple second aeration holes at the bottom. The secondary aeration pipe (8) is used to disturb the slurry and wash the fine sand. The sand outlet at the bottom of the sand removal and fine separation tank (7) is connected to the feed inlet of the secondary screw conveyor (10), and a secondary electric gate (9) is installed at the sand outlet of the sand removal and fine separation tank (7).

2. The integrated device for removing slag and sand from kitchen slurry according to claim 1, characterized in that: The chain plate scraper assembly (2) includes a motor (2-6), a drive chain shaft (2-4), a driven chain shaft (2-2), multiple scraper plates (2-1), and two chains (2-3). The drive chain shaft (2-4) and the driven chain shaft (2-2) are mounted on the slag collection tank (3) through bearing seats (3-2). The drive chain shaft (2-4) has drive sprockets at both ends, and the driven chain shaft (2-2) has driven sprockets at both ends. The two chains (2-3) are mounted on the drive sprockets and the driven sprockets respectively. The output side of the motor (2-6) mounted on the slag collection tank (3) is connected to the drive chain shaft (2-4). The two ends of the scraper plates (2-1) are mounted on the two chains (2-3).

3. An integrated device for removing slag and sand from kitchen slurry according to claim 1 or 2, characterized in that: The slag scraper (2-1) includes two slag plate seats (2-11) and a scraper (2-12). The slag plate seats (2-11) are L-shaped and mounted on the corresponding chains (2-3). The two ends of the scraper (2-12) are mounted on the slag plate seats (2-11) by fasteners.

4. The integrated device for removing slag and sand from kitchen slurry according to claim 1, characterized in that: The shaftless screw conveyor of the first-stage screw conveyor has a constant outer diameter of the screw blades, the same pitch in the front middle section of the screw blades, and the pitch of the screw blade extrusion section is 1.5 to 2.5 times the pitch of the front middle section of the screw blades.

5. The integrated device for removing slag and sand from kitchen slurry according to claim 1, characterized in that: The primary aeration pipe (4) is arranged in a ring inside the sand removal and coarse separation tank (1). The first aeration holes on the primary aeration pipe (4) are arranged circumferentially and axially along the pipe wall, and the diameter of the first aeration holes is between 3 and 5 mm.

6. The integrated device for removing slag and sand from kitchen slurry according to claim 1, characterized in that: The included angle of the tank wall of the coarse sand settling zone (1-4) of the sand removal coarse separation tank (1) is between 60±5°.

7. The integrated device for removing slag and sand from kitchen slurry according to claim 1, characterized in that: The secondary aeration pipe (8) is arranged in a ring inside the sand removal and fine separation tank (7). The second aeration holes on the secondary aeration pipe (8) are arranged circumferentially and axially along the pipe wall, and the diameter of the second aeration holes is between 0.5 and 1 mm.

8. The integrated device for removing slag and sand from kitchen slurry according to claim 1, characterized in that: The diameter-to-height ratio of the sand removal and purification tank (7) is between 1:1.25 and 1.

5. Four to eight guide plates (7-2) are evenly distributed around the sand removal and purification tank (7). The downward inclination angle of the guide plate (7-2) to the horizontal plane is between 40±5°. The bottom surface of the guide plate (7-2) is provided with multiple first guide ribs to form a concave-convex surface. The height of the first guide ribs is between 1 and 5 mm, and the distance between adjacent first guide ribs is between 50±10 mm.

9. An integrated device for removing slag and sand from kitchen slurry according to claim 1, characterized in that: The central cylinder (7-4) is provided with a plurality of sand baffles (7-5) that slope downward from the outside to the inside along the circumference and height direction. The lower part of the sand baffles (7-5) is provided with a plurality of second guide ribs (7-51) and forms a concave-convex surface. The height of the second guide ribs (7-51) is between 1 and 5 mm, and the distance between adjacent second guide ribs (7-51) is between 50 ± 10 mm.

Images