CN111570478A

CN111570478A - Municipal administration domestic mixed waste screening processing system

Info

Publication number: CN111570478A
Application number: CN202010445188.6A
Authority: CN
Inventors: 兰剑; 郑琳珠; 胡京招; 王文魁; 林挺; 伍立说; 王海荣; 马源; 吴腾伟
Original assignee: CCCC National Engineering Research Center of Dredging Technology and Equipment Co Ltd
Current assignee: CCCC National Engineering Research Center of Dredging Technology and Equipment Co Ltd
Priority date: 2020-05-23
Filing date: 2020-05-23
Publication date: 2020-08-25

Abstract

A municipal domestic mixed garbage screening treatment system is characterized by comprising a garbage crushing and separating device (1), a conveying and feeding device (2), a screening device (3), a high-pressure flushing device (5), a mud pit (6), a harmless treatment tank (7) and a plate-and-frame filter press (8); the garbage is primarily sorted by the crushing and separating device (1) and then is conveyed to the screening device (3) by the conveying and feeding device (2); the screening device (3) is used for carrying out secondary screening on the garbage and sorting the garbage into slurry, small particle blocks and large particle block garbage; the high-pressure flushing device (5) cleans the screening device (3) to prevent the screening holes of the screen drum from being blocked; after the mud passes through a mud pit (6), the mud is subjected to innocent treatment by an innocent treatment tank (7) and is treated by a plate-and-frame filter press (8) to generate mud cakes. All devices of the system are arranged in a production line for operation, so that the system has a good separation effect and remarkably improves the garbage treatment efficiency.

Description

Municipal administration domestic mixed waste screening processing system

Technical Field

The invention relates to a municipal domestic mixed garbage screening treatment system.

Background

At present, the garbage disposal mode in China generally comprises three types: landfill, incineration, and composting. The most important mode of municipal waste treatment is landfill, which accounts for about 70% of the total treatment capacity. Most of the garbage landfill modes treat different types of garbage indiscriminately, occupy a large amount of land resources, and harmful substances generated by long-term garbage stacking easily have adverse effects on the surrounding natural environment. The garbage classification measures are not widely implemented, and the construction garbage and the domestic garbage of urban and rural municipal administration and the like are mixed and stacked after being transported to suburbs, cannot be effectively treated for a long time, generate a large amount of harmful microorganisms, malodorous gas and the like, and are harmful to the environment. In order to effectively treat municipal domestic mixed garbage, various garbage treatment equipment is invented, but the existing garbage treatment equipment has the following problems: solid particle dry waste is easy to cause blockage of screening equipment; high-concentration organic waste liquid generated by extruding and dehydrating wet garbage through equipment needs to be treated by independently designing a treatment process; the amount of tap water required for garbage treatment is large, and the treatment difficulty of the generated wastewater is large; the energy consumption of the equipment is large, and the operation efficiency is low.

Disclosure of Invention

The utility model provides an aim at overcomes prior art's is not enough, provides a municipal administration domestic mixed waste screening processing system, carries out the systematization to municipal administration domestic waste and handles, disposes devices such as multistage screening, high pressure bath to remedy screening equipment and block up, design alone and handle rubbish waste liquid technology etc. not enough.

The technical scheme provided by the application is as follows:

the utility model provides a municipal administration domestic mixed waste screening processing system which characterized in that pulverizes separator 1, carries feed arrangement 2, screening plant 3, high pressure flushing device 5, mud pit 6, innocent treatment jar 7, plate and frame filter press 8 including rubbish.

The garbage crushing and separating device 1 comprises a crushing device 11 and an overturning screen device 12; the crushing device 11 comprises a hopper 112, rollers 111.

The overturning screen device 12 comprises an overturning screen 121, an overturning motor (not shown in the figure) and a spring 122; the spring 122 is arranged between the crushing device 11 and the overturning screen 121 and is positioned on one side of the overturning screen device 12, so that the overturning screen 121 is inclined, when garbage is thrown in, the garbage is firstly primarily screened by the overturning screen 121 due to vibration of the spring 122, large garbage is blocked on the screen, and small garbage enters the crushing device 11; the turning screen 121 is driven by the turning motor to complete turning action, and large garbage on the screen 121 is poured into a coarse material accumulation position beside the garbage crushing and separating device 1.

The grinding device 11 is provided with a plurality of rollers 111 which are arranged in parallel, the rollers 111 are provided with a tooth-shaped structure, the teeth of the adjacent rollers 111 are meshed with each other, and the rollers 111 rotate in the same direction during working; the small garbage primarily screened by the overturning screen 121 is further crushed by means of the mutual meshing action of the rollers 111, and the crushed garbage enters the conveying and feeding device 2.

The conveying and feeding device 2 is a multi-stage conveying device, and each conveying device comprises a belt pulley 21, a belt 22 and a fender 23; the belt 22 is attached to the belt pulley 21, and the belt pulley 21 rotates to drive the belt 22 to move; the fender 23 is arranged on two sides of the belt, so that garbage on the belt is prevented from shaking to cause falling in the transportation process.

The screening device 3 comprises a screening device which comprises an inner layer roller 31, an outer layer roller 32, a coarse material output port 33, a fine material output port 34 and a driving device 35; the drive device 35 includes a motor 351, a speed reducer 352, and a coupling 353.

From the aspect of shape, the inner layer roller 31 and the outer layer roller 32 are both in the shape of a circular truncated cone side surface, the central axis of the circular truncated cone is in the horizontal direction, one side close to the conveying device 2 is the lower bottom surface (namely the surface with a large diameter) of the circular truncated cone, the upper bottom surface of the circular truncated cone is in a sealed shape, the lower bottom surface is in an open shape, the central axis of the upper bottom surface of the circular truncated cone is connected with a driving device 35 after extending, and the driving device 35 provides; the diameter (the diameter of the upper bottom surface and the lower bottom surface) of the outer layer roller 32 is larger than that of the inner layer roller 31, the inner layer roller 31 and the outer layer roller 32 are both of net-shaped steel structures, and the outer layer roller 32 is sleeved outside the inner layer roller 31 to form a double-layer screen structure; the mesh holes of the inner layer roller 31 are larger, and the mesh holes of the outer layer roller 32 are smaller; the coarse material output port 33 is arranged at the bottom of the right side (the lower bottom surface of the circular truncated cone) of the inner-layer roller 31; the fine material outlet 34 is arranged at the bottom of the right side (the lower bottom surface of the circular truncated cone) of the outer layer roller 32.

The inner layer roller 31 and the outer layer roller 32 are in a slope shape, garbage with the diameter larger than the diameter of the grid holes of the inner layer roller 31 is limited in the inner layer roller 31 and then is conveyed to the coarse material output port 33 through the slope of the inner layer roller 31; garbage with the diameter smaller than the diameter of the mesh holes of the inner layer roller 31 enters the outer layer roller 32 through the holes of the inner layer roller 31; the garbage larger than the diameter of the mesh holes of the outer roller 32 is confined between the outer roller 32 and the inner roller 31 and is conveyed to the fine material outlet 34 through the slope of the outer roller 32, and the fine particle garbage smaller than the diameter of the mesh holes of the outer roller 32 flows to the slurry tank 6.

The high-pressure flushing device 5 comprises a high-pressure flushing pump set 51, a high-pressure flushing pipeline 52 and a nozzle 53; the nozzles 53 are uniformly distributed on the high-pressure flushing pipeline 52, and the high-pressure flushing device 5 improves the spraying area by utilizing the combination of the high-pressure flushing pipeline 52 and the nozzles 53; the high-pressure flushing pipeline 52 comprises a lower flushing pipeline 521, a middle flushing pipeline 522 and an upper flushing pipeline 523; and a liquid level water pipe on the mud pit (6) is connected with a water outlet and an external water pipe to form a high-pressure flushing water source together, and is connected with a high-pressure flushing pump set (51).

The lower water flushing pipeline 521 is horizontally arranged in the inner layer roller 31 and is close to the lower inner wall of the inner layer roller 31 and used for downwards cleaning the inner layer roller 31; the middle flushing pipeline 522 is horizontally arranged in the inner layer roller 31 and above the conveying and feeding device 2 and is used for cleaning fine particles in the garbage on the conveying and feeding device 2 to disperse the garbage, so that the garbage is convenient for soluble substances such as soil to form a solution and is separated from the solid garbage; the upper flushing pipeline 523 is parallel to the outer drum 32 of the screening device 3, is installed outside the outer drum 32, flushes high-pressure water from the outside of the screening device 3 to the inside of the screening device 3, flushes the garbage attached to the inner wall of the inner drum and the outer drum of the screening device 3, and prevents the screening drum from being blocked.

The mud pit (6) is funnel-shaped, is arranged below a roller of the screening device (3), is formed by pouring cement and is used for containing mud solution of garbage on a flushing pipeline (522) in the screening device (3) and flushing a belt (22); after the slurry solution is precipitated, the supernatant enters a high-pressure flushing pump set (51) for recycling, and the lower slurry enters a harmless treatment tank (7).

The innocent treatment tank 7 is slurry heavy metal treatment equipment; the lower end is provided with a slurry outflow pipeline, and the slurry after innocent treatment enters a plate-and-frame filter press 8.

And the plate-and-frame filter press 8 dehydrates the mud treated by the innocent treatment tank 7 to form mud cakes.

Compared with the prior art, the beneficial effect of this application lies in:

the mixture of the building garbage, the household garbage and the sludge can be screened into large stones, small stones and slurry, the screening effect is good, and the screened waste can be effectively utilized; the garbage screening device is provided with a high-pressure washing device to wash out mud and sand in the garbage, so that the formation of subsequent slurry is facilitated;

harmful substances in the garbage are reduced to the minimum by adopting a physical and chemical method, so that the pollution to the environment is avoided; the invention can separate effective fruits of the garbage, and the slurry finally forms dehydrated and dried usable soil, thereby realizing resource recycling.

The system only discloses the process and is combined with a special structure, and when the system is applied in the future, full-automatic assembly line operation can be realized only by combining an electric control part. The electrical control part is not the object of the invention and the necessary technical features of the solution of the present application.

Drawings

FIG. 1 is a schematic view of a municipal solid waste screening system;

fig. 2 is a left view radial screenshot of fig. 1 at the screening device 3;

digital tag annotation:

1 garbage crushing and separating device, 11 crushing device, 12 overturning screen device, 111 roller, 112 hopper, 121 overturning screen, 122 roller, 2 conveying and feeding device, 21 belt pulley, 22 belt, 23 fender, 3 screening device, 31 inner layer roller, 32 outer layer roller, 33 coarse material output port, 34 fine material output port, 35 driving device, 351 motor, 352 reducer, 353 coupler, 4 telescopic carding device, 41 telescopic cylinder, 42 carding brush, 5 high-pressure flushing device, 51 high-pressure flushing pump set, 52 high-pressure flushing pipeline, 53 nozzle, 521 lower flushing pipeline, 522 middle flushing pipeline, 523 upper flushing pipeline, 6 mud pit, 7 innocent treatment tank and 8 plate and frame filter press.

Detailed Description

In order to make the technical solutions of the present invention better understood, the present invention is described in detail below with reference to the accompanying drawings and examples.

Example 1:

as shown in figure 1, the municipal domestic mixed garbage screening treatment system comprises a garbage crushing and separating device 1, a conveying and feeding device 2, a screening device 3, a high-pressure flushing device 5, a supporting device 6, a mud pit 6, a harmless treatment tank 7 and a plate-and-frame filter press 8, and in order to increase the cleaning capacity of the system, a telescopic carding device 4 is added as an embodiment system, wherein the devices in the embodiment system are arranged in a production line.

The conveying and feeding device 2 is a multi-stage conveying device, and each conveying device comprises a belt pulley 21, a belt 22 and a fender 23; the belt (22) is attached to the belt pulley (21), and the belt pulley (21) rotates to drive the belt (22) to move; the front-stage conveying device is higher than the rear-stage conveying device, and the belts 22 at the joints of the front-stage conveying device and the rear-stage conveying device are overlapped in a certain length, so that the stability of conveying the garbage is ensured; the conveying device is used for conveying the garbage separated by the garbage crushing and separating device and conveying the garbage to the inside of the roller of the screening device; the belt pulley 21 provides power for the rotation of the belt; the fender 23 is arranged on two sides of the belt, so that garbage on the belt is prevented from shaking to cause falling in the transportation process.

The screening device 3 comprises a screening device which comprises an inner layer roller 31, an outer layer roller 32, a coarse material output port 33, a fine material output port 34 and a driving device 35; the driving device 35 includes a motor 351, a speed reducer 352, and a coupling 353; the driving device 35 is connected with the roller rotating shaft through a coupler 353 to provide power for the rotation of the roller.

The screening device 3 is provided with a fixing device for providing a support bracket for the screening device 3.

After the garbage conveyed by the conveying and feeding device 2 enters the screening device 3, the inner layer roller 31 and the outer layer roller 32 start to rotate; the inner layer roller 31 and the outer layer roller 32 are in a slope shape, the conveying and feeding device 2 dumps the garbage to the left side (the upper bottom surface of the circular truncated cone) close to the inner layer roller 31, the garbage larger than the diameter of the grid holes of the inner layer roller 31 is limited in the inner layer roller 31, and then the garbage is rolled to the coarse material output port 33 through the slope of the inner layer roller 31; garbage with the diameter smaller than the mesh hole diameter of the inner roller 31 enters the outer roller 32 through the pores of the inner roller 31, and similarly, garbage with the diameter larger than the mesh hole diameter of the outer roller 32 is limited between the outer roller 32 and the inner roller 31, the garbage is rolled to the fine material output port 34 through the slope of the outer roller 32, and fine particle garbage with the diameter smaller than the mesh hole diameter of the outer roller 32 flows to the mud pit 6.

As an embodiment, the system can further comprise an electric part and a retractable combing device 4 when in specific application, the retractable combing device 4 can be designed with a retractable cylinder 41 and a combing brush 42, and the retractable action of the combing brush 42 can be realized; the retractable carding device 4 is parallel to the inner upper wall of the inner layer roller 31 in the screening device 3, and the stretched carding brush 42 is in contact with the inner upper wall of the inner layer roller 31; when the screening device 3 works, the telescopic carding device 4 controls the telescopic cylinder 41 to stretch the carding brush 42 into the screening device and contact with the inner upper wall of the inner layer roller 31, the carding brush 42 cleans garbage (such as plastic bags, cloth strips and the like) on the meshes of the inner wall of the inner layer roller 31 in the rotation process of the inner layer roller 31, and when the screening device 3 stops rotating, the telescopic carding device 4 withdraws the carding brush 42 out of the screening device 3 and works again after cleaning.

The high-pressure flushing device 5 comprises a high-pressure flushing pump set 51, a high-pressure flushing pipeline 52 and a nozzle 53; the high-pressure flushing pipeline 52 is uniformly provided with nozzles 53, and high-pressure water is directionally sprayed through the nozzles 53; the high-pressure flushing pipeline 52 comprises a lower flushing pipeline 521, a middle flushing pipeline 522 and an upper flushing pipeline 523; the high-pressure flushing pump set 51 is connected with an upper water outlet and an external water pipe of the mud pit 6; the water at the water outlet of the mud pool 6 is supernatant liquid after mud sedimentation, and the water in the external water pipe comes from a municipal pipe network; as shown in fig. 2, the lower water flushing pipe 521 is horizontally arranged in the inner drum 31, close to the lower inner wall of the inner drum 31, for washing the inner drum 31 downward; the middle flushing pipeline 522 is horizontally arranged in the inner layer roller 31 and above the conveying and feeding device 2 and is used for cleaning fine particles in the garbage on the conveying and feeding device 2 so as to disperse the garbage, so that the garbage is convenient for soluble substances such as soil to form a solution and is separated from the solid garbage; the upper flushing pipe 523 is parallel to the outer drum 32 of the screening device 3, is installed outside the outer drum 32, flushes high-pressure water from the outside of the screening device 3 to the inside of the screening device 3, flushes the garbage attached to the inner wall of the inner drum and the outer drum of the screening device 3, and prevents the screening drum from being blocked.

The supporting device comprises a bearing and a system supporting frame, and provides support for the whole system.

The mud pit 6 is funnel-shaped, is arranged below a roller of the screening device 3 and is formed by pouring cement, prevents heavy metal from permeating soil to pollute soil, and is used for containing mud solution flushed down by the screening device 3; after the slurry solution is precipitated, the supernatant enters a high-pressure flushing pump set 51 for recycling; a plunger pumping device is arranged at the discharge port of the mud pool 6 and pumps mud to the harmless treatment tank 7.

The innocent treatment tank 7 is special slurry treatment equipment; the upper end of the side wall is provided with a slurry inflow pipeline, the tank is internally provided with a helical blade, the blades rotate to uniformly mix the slurry during operation, harmful substances such as heavy metals in the slurry are removed by physical and chemical methods, the lower end of the side wall is provided with a slurry outflow pipeline, and the slurry after harmless treatment enters the plate-frame filter press 8.

The plate-and-frame filter press 8 is in the prior art, and the plate-and-frame filter press 8 dehydrates the slurry treated by the innocent treatment tank 7 to form a mud cake.

Further optimizing the technical scheme:

the inner layer roller 31 has a mesh opening single hole size of about 50mmX50mm, and the outer layer roller 32 has a mesh opening single hole size of about 20X20 mm;

example 2:

referring to fig. 1, a municipal domestic mixed waste screening treatment method adopts the municipal domestic mixed waste screening treatment system of the embodiment 1, and comprises the following specific steps:

firstly, the garbage crushing and separating device 1 crushes the soft bulk garbage and separates the bulk hard stone, concrete and other wastes; conveying the primarily treated garbage to a feeding hole of a screening device 3 through a conveying and feeding device 2; the inner wall of the screening device 3 is cleaned by the telescopic carding device 4, so that the screening cylinder is prevented from being blocked; the outer wall of the screening device is washed by the high-pressure flushing device 5, so that the screening holes of the screening cylinder are prevented from being blocked, the mud in the garbage is diluted, and the garbage is diluted, so that the garbage mud smoothly flows through the screening cylinder and is discharged; separating the primary treated garbage by a sieving and subpackaging device 3, wherein the garbage is secondarily treated into slurry, small particle blocks and large particle blocks; the garbage mud is precipitated through a mud pit 6; carrying out innocent treatment on the slurry through an innocent treatment tank 7; the treated slurry is sent to a plate-and-frame filter press 8 to be compressed into a mud cake.

The garbage screening and processing method of the system comprises the following steps:

s1, receiving the original garbage;

s2, crushing large hard stones and the like in the garbage into small blocks by using the garbage crushing device 1, and separating the large hard stones;

s3, pouring the primarily screened garbage on the conveying and feeding device 2, and conveying the garbage into the inner layer roller 31 of the screening device 3;

s4, the screening device 3 operates to sort the garbage into large, medium and small particle size particles and sundries such as cloth strips and plastic bags which are difficult to clean;

s5, conveying the fine particles to a mud pit 6 and mixing the fine particles into mud with a certain concentration;

s6, conveying the slurry to a harmless treatment tank 7 for harmless treatment;

the slurry treated by the S7 is concentrated and pressed into solid mud blocks by a plate-and-frame filter press 8 for sustainable reuse.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A municipal domestic mixed garbage screening treatment system is characterized by comprising a garbage crushing and separating device (1), a conveying and feeding device (2), a screening device (3), a high-pressure flushing device (5), a mud pit (6), a harmless treatment tank (7) and a plate-and-frame filter press (8);

the garbage crushing and separating device (1) comprises a crushing device (11) and an overturning screen device (12); the crushing device (11) comprises a hopper (112) and a roller (111);

the overturning screen device (12) comprises an overturning screen (121), an overturning motor (not shown in the figure) and a spring (122); the spring (122) is arranged between the crushing device (11) and the overturning screen (121) and is positioned on one side of the overturning screen device (12), so that the overturning screen (121) is inclined, when garbage is thrown in, the garbage is primarily screened by the overturning screen (121) under the vibration action of the spring (122), large garbage is blocked on the screen, and small garbage enters the crushing device (11); the overturning screen (121) completes overturning action under the driving of an overturning motor, and large garbage on the screen (121) is poured into a coarse material accumulation part accumulated beside the garbage crushing and separating device (1);

the grinding device (11) is provided with a plurality of rollers (111) which are arranged in parallel, the rollers (111) are provided with tooth-shaped structures, the teeth of adjacent rollers (111) are meshed with each other, and the rollers (111) rotate in the same direction during working; further crushing the small garbage primarily screened by the overturning screen (121) by means of mutual meshing action of the teeth of the rollers (111), and feeding the crushed garbage into a conveying and feeding device (2);

the conveying and feeding devices (2) are multistage conveying devices which are sequentially connected in series from high to low, and each conveying device comprises a belt pulley (21), a belt (22) and a fender (23); the belt (22) is attached to the belt pulleys (21) at the two ends, and the belt pulleys (21) rotate to drive the belt (22) to move; the fender boards (23) are arranged on two sides of the belt, so that garbage on the belt is prevented from vibrating and falling off in the transportation process;

the screening device (3) comprises an inner layer roller (31), an outer layer roller (32), a coarse material output port (33), a fine material output port (34) and a driving device (35); the inner layer roller (31) and the outer layer roller (32) are both in the shape of the side surface of a circular truncated cone, the central axis of the circular truncated cone is in the horizontal direction, one side close to the conveying device (2) is the lower bottom surface of the circular truncated cone, the upper bottom surface of the circular truncated cone is sealed, and the lower bottom surface of the circular truncated cone is open; the central shaft of the upper bottom surface of the circular truncated cone extends and then is connected with a driving device (35), and the driving device (35) provides power for the rotation of the roller; the inner layer roller (31) and the outer layer roller (32) are both of a net-shaped steel structure, and the outer layer roller (32) is sleeved outside the inner layer roller (31) to form a double-layer screen structure; the mesh holes of the inner layer roller (31) are larger, and the mesh holes of the outer layer roller (32) are smaller; the coarse material output port (33) is arranged at the lower bottom surface of the right circular table of the inner layer roller (31); the fine material output port (34) is arranged at the lower bottom surface of the right circular table of the outer layer roller (32);

the high-pressure flushing device (5) comprises a high-pressure flushing pump set (51), a high-pressure flushing pipeline (52) and a nozzle (53); a plurality of nozzles (53) are uniformly distributed on the high-pressure flushing pipeline (52) and matched with the screening device (3) to complete the screening operation;

the high-pressure flushing pipeline (52) comprises a lower flushing pipeline (521), a middle flushing pipeline (522) and an upper flushing pipeline (523); a liquid level water pipe on the mud pit (6) is connected with a water outlet and an external water pipe to form a selectable water source for high-pressure flushing together, and is connected with a high-pressure flushing pump set (51);

the mud pit (6) is funnel-shaped, is arranged below the roller of the screening device (3), is formed by pouring cement and is used for containing mud solution of garbage on the belt (22) flushed by the middle flushing pipeline (522) in the screening device (3); after the slurry solution is statically precipitated, the supernatant enters a high-pressure flushing pump set (51) for cyclic utilization, and the lower slurry enters a harmless treatment tank (7);

the innocent treatment tank (7) is mud heavy metal treatment equipment; the lower end is provided with a slurry outflow pipeline, and the slurry after the harmless treatment enters a plate-and-frame filter press (8);

and the plate-and-frame filter press (8) dehydrates the mud treated by the innocent treatment tank (7) to form mud cakes.

2. The municipal solid waste screening system of claim 1, wherein:

the inner layer roller (31) and the outer layer roller (32) are in a slope shape, garbage with the diameter larger than the diameter of the grid holes of the inner layer roller (31) is limited in the inner layer roller (31), and then the garbage is conveyed to the coarse material output port (33) through the slope of the inner layer roller (31); garbage with the diameter smaller than the diameter of the mesh holes of the inner layer roller (31) enters the outer layer roller (32) through the holes of the inner layer roller (31); the garbage larger than the diameter of the mesh holes of the outer layer roller (32) is limited between the outer layer roller (32) and the inner layer roller (31) and is conveyed to a fine material outlet (34) through the slope of the outer layer roller (32), and the fine particle garbage smaller than the diameter of the mesh holes of the outer layer roller (32) flows to the mud pit (6).

3. The municipal solid waste screening system of claim 1, wherein:

the lower water flushing pipeline (521) is horizontally arranged in the inner layer roller (31) and is close to the lower inner wall of the inner layer roller (31) and used for downwards cleaning the inner layer roller (31);

the middle flushing pipeline (522) is horizontally arranged in the inner layer roller (31), is arranged above the conveying and feeding device (2) and is used for cleaning fine particles in the garbage on the conveying and feeding device (2) to disperse the garbage, so that soluble substances such as soil and the like can form solution conveniently to be separated from the solid garbage;

the upper flushing pipeline (523) is parallel to the outer layer roller (32) in the screening device (3), is arranged outside the outer layer roller (32), flushes high-pressure water from the outside of the screening device (3) to the inside of the screening device (3), flushes garbage attached to the inner wall of the inner roller and the outer roller of the screening device (3) down, and prevents the screening roller from being blocked.