A screw press

Abstract

The present invention provides a screw press, comprising: a frame; a feed hopper; a pressing screw connected to the feed hopper for pushing materials; a driving motor connected to the pressing screw for driving the pressing screw to move; a screen located between the pressing screw and the frame; a back pressure device connected to the slag discharge end of the pressing screw for squeezing the materials pushed by the pressing screw to obtain solid slag and slurry; a discharge port arranged at the slag discharge end of the pressing screw for discharging solid slag; a slurry mixing and sand removal hopper arranged below the screen for accommodating slurry filtered by the screen; a sand lifting screw connected to the slurry mixing and sand removal hopper for discharging heavy materials in the slurry through the sand discharge port at the end of the sand lifting screw; and a slurry outlet for discharging the slurry after sand removal. According to the present invention, the solid-liquid separation of materials is better achieved, the resource recovery rate is improved, and at the same time, the operating pressure and load of subsequent processing equipment are reduced, and the service life and maintenance cycle of the equipment are extended.

Description

Technical Field

[0001] The invention relates to the technical field of environmental protection, and more particularly to a screw press. Background Art

[0002] Screw presses are mainly used for solid-liquid separation of materials and are widely used. For example, they are used in drainage pumping stations, sewage treatment plants and water plants to dehydrate and compress the residues intercepted by the trash screen; they are used in papermaking, brewing, food, leather, textile, printing and dyeing, petrochemical and other industries to dehydrate and compress raw materials, wastewater or slurry; they are used in livestock and poultry manure, anaerobic biogas residue dehydration and other treatments. In recent years, screw presses have been gradually applied to the catering waste and kitchen waste treatment industries. Due to the large differences in the components of different materials, the performance requirements of the screw press are high for materials with more complex components and high impurity content. If the content of organic matter, grease or other reusable components in the treatment object is high, in order to improve the resource recovery rate and ensure economic benefits, the extraction rate of reusable components should be increased as much as possible. At present, conventional screw presses have high failure rates, high moisture content in slag, high losses of organic matter, etc. in actual operation, the screen needs to be manually cleaned, which affects the environmental sanitation of the workshop, and the slurry needs additional sand removal equipment for further processing. The overall process route is complex, the number of equipment is large, and the area occupied is large. Summary of the invention

[0003] The present invention is proposed in view of the above problems. The present invention provides a screw press to solve at least one of the above problems.

[0004] According to the present invention, a screw press is provided, comprising:

[0005] frame;

[0006] A feed hopper is arranged above the frame and is used to feed materials;

[0007] A pressing screw, arranged inside the frame and connected to the feed hopper, for pushing the material;

[0008] A driving motor connected to the squeezing screw and used to drive the squeezing screw to move;

[0009] A screen is coaxially arranged with the pressing screw and located between the pressing screw and the frame;

[0010] A back pressure device, connected to the slag discharge end of the pressing screw, for applying back pressure to the material in the pressing screw to squeeze the material pushed by the pressing screw to obtain solid slag and slurry;

[0011] A discharge port, arranged at the slag discharge end of the squeezing screw, for discharging the solid slag;

[0012] A slurry mixing and sand removal hopper is arranged below the screen and is used to contain the slurry filtered by the screen;

[0013] A sand lifting screw is connected to the slurry adjustment and sand removal hopper and is used to discharge heavy materials in the slurry through a sand discharge port provided at the end of the sand lifting screw;

[0014] The slurry outlet is arranged in the middle or upper part of the slurry adjustment and sand removal hopper, and is used to discharge the slurry after the sand is removed.

[0015] Optionally, the pressing screw comprises:

[0016] There is a spiral blade area and a spiral blade-free area, wherein the spiral blade area is close to the feed end of the pressing screw, and the spiral blade-free area is close to the slag discharge end of the pressing screw.

[0017] Optionally, the pressing screw includes a hollow shaft for introducing steam or hot water to preliminarily heat the material.

[0018] Optionally, the screen includes a fixed screen and a movable screen, the fixed screen corresponds to the region with spiral blades, the movable screen corresponds to the region without spiral blades, and can move along the pressing screw.

[0019] Optionally, the diameter of the movable screen is larger than the diameter of the fixed screen.

[0020] Optionally, the screw press further comprises:

[0021] A hydraulic device is connected to the back pressure device and is used to drive the back pressure device.

[0022] Optionally, the screw press further comprises:

[0023] A top cover is arranged on the top of the screw press and is connected to the feed hopper.

[0024] Optionally, the screw press further comprises:

[0025] A cleaning device is arranged inside the top cover and is used for cleaning the screen.

[0026] Optionally, the cleaning device comprises:

[0027] A plurality of cleaning branch pipes are respectively arranged at intervals inside the top cover;

[0028] Each of the cleaning branch pipes is provided with a plurality of spray openings facing the screen, and the cleaning liquid is radially sprayed on the screen through the spray openings.

[0029] Optionally, the screw press further comprises:

[0030] The reclaimed water return port is arranged in the middle or upper part of the slurry adjustment and sand removal hopper, and is used to input reclaimed water at a predetermined angle to dilute the slurry.

[0031] According to the screw press of the embodiment of the present invention, a slurry adjustment and sand removal bucket is arranged at the lower part of the press to collect the squeezed slurry, and heavy materials such as gravel, shells, ceramics, glass, metals, etc. in the slurry are discharged through the bottom screw conveyor, thereby reducing the operating pressure and load of subsequent processing equipment, extending the service life and maintenance cycle, and the organic slurry after sand removal is discharged from the slurry outlet. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other purposes, features and advantages of the present invention will become more apparent by describing the embodiments of the present invention in more detail in conjunction with the accompanying drawings. The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0033] Figure 1 is an example of a screw press according to an embodiment of the present invention;

[0034] Figure 2 is an example of a cleaning device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the present invention more obvious, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited to the exemplary embodiments described herein. Based on the embodiments of the present invention described in the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the protection scope of the present invention.

[0036] In the use of screw presses, the components of different materials vary greatly. For materials with more complex components and high impurity content, high performance requirements are placed on the screw press. If the content of organic matter, oil or other recyclable components in the treatment object is high, in order to improve resource recycling rate and ensure economic benefits, the extraction rate of recyclable components should be increased as much as possible. At present, conventional screw presses have high failure rates, high slag moisture content, high organic matter losses, and the screen needs to be manually cleaned, which affects the environmental sanitation of the workshop. The slurry needs additional sand removal equipment for further treatment. The overall process route is complex, the number of equipment is large, and the floor space is large.

[0037] Based on the above considerations, a screw press is provided according to an embodiment of the present invention. Figure 1 , Figure 1 An example of a screw press according to an embodiment of the present invention is shown. Figure 1 As shown, the screw press 100 comprises:

[0038] Rack 1;

[0039] A feed hopper 3 is provided above the frame 1 and is used for feeding materials;

[0040] A pressing screw 10 is disposed inside the frame 1 and is connected to the feed hopper 3 to push the material;

[0041] A driving motor 2, connected to the squeezing screw 10, for driving the squeezing screw 10 to move;

[0042] A screen, coaxially arranged with the pressing screw 10 and located between the pressing screw 10 and the frame 1;

[0043] A back pressure device 5 is connected to the slag discharge end of the pressing screw 10 and is used to apply back pressure to the material in the pressing screw 10 to squeeze the material pushed by the pressing screw 10 to obtain solid slag and slurry;

[0044] A discharge port 7 is provided at the slag discharge end of the squeezing screw 10 and is used to discharge the solid slag;

[0045] A slurry mixing and sand removal hopper 12 is disposed below the screen and is used to contain the slurry filtered by the screen;

[0046] The sand lifting screw 15 is connected to the slurry mixing and sand removal hopper 12 and is used to discharge the heavy materials in the slurry through the sand discharge port 16 provided at the end of the sand lifting screw 15;

[0047] The slurry outlet 14 is arranged in the middle or upper part of the slurry adjustment and sand removal hopper 12, and is used to discharge the slurry after the sand is removed.

[0048] Among them, the material enters the screw press through the feed hopper 3, and the driving motor 2 drives the pressing screw 10 to push the material. Under the joint action of the pressing screw 10 and the back pressure device 5, the material is squeezed to achieve solid-liquid separation. The solid residue after pressing is discharged from the discharge port 7, and the slurry falls into the slurry adjustment and sand removal hopper 12 at the bottom; the heavy materials such as gravel, shells, ceramics, glass, metals in the slurry are discharged through the sand discharge port 16 by the sand lifting screw 15, and the slurry after sand removal is discharged from the slurry outlet 14 to enter the subsequent processing process; the pressing and sand removal processes are combined into one, which reduces the operating pressure and load of the subsequent processing equipment and extends the service life and maintenance cycle of the equipment.

[0049] In some embodiments, the material may be food waste or any other material that needs to be squeezed.

[0050] Optionally, the pressing screw 10 includes a region with spiral blades and a region without spiral blades, wherein the region with spiral blades is close to a feeding end of the pressing screw 10 , and the region without spiral blades is close to a slag discharge end of the pressing screw 10 .

[0051] The length of the area with spiral blades and the length of the area without spiral blades can be set as needed. For example, the squeezing screw 10 near the discharge port 7 can be designed without spiral blades of a reasonable length, so as to form a plugging area 11 between the area without spiral blades and the screen, further ensuring the squeezing efficiency.

[0052] In some embodiments, the pressing screw 10 includes a hollow shaft for passing steam or hot water to preliminarily heat the material. The pressing screw 10 is designed as a hollow shaft. According to the operation conditions, steam or hot water can be used as a heating medium to preliminarily increase the temperature of the pressed material and reduce the viscosity, so as to improve the pressing efficiency, thereby improving the solid-liquid separation efficiency, so that as many reusable components in the material as possible enter the slurry, and ensure a high resource recovery rate.

[0053] Optionally, the screen may include a fixed screen 8 and a movable screen 9, wherein the fixed screen 8 corresponds to the region with spiral blades, and the movable screen 9 corresponds to the region without spiral blades and can move along the pressing screw.

[0054] In some embodiments, the diameter of the movable screen 9 is greater than the diameter of the fixed screen 8 .

[0055] Among them, when the screw press is under inspection and maintenance, and the internal material needs to be emptied, the movable screen 9 can be moved toward the feed hopper 3. Under the pushing action of the pressing screw 10, the material falls from the material plug area 11 into the slurry mixing and sand removal hopper 12, and is discharged through the sand lifting screw 15. The equipment can be emptied by fully automatic operation, avoiding manual operation and keeping the workshop environment clean and tidy.

[0056] Optionally, the screw press further comprises:

[0057] The hydraulic device 6 is connected to the back pressure device 5 and is used to drive the back pressure device 5 .

[0058] The back pressure device 5 is driven by a hydraulic device 6, and the back pressure can be adjusted according to the material characteristics and needs to ensure that the moisture content of the discharged slag meets the requirements. At the same time, the plug area 11 near the discharge end of the squeezing screw 10 ensures a low moisture content of the discharged slag through the dual effects of back pressure between the materials and the discharge end.

[0059] Optionally, the screw press further comprises:

[0060] A top cover 4 is disposed on the top of the screw press and is connected to the feed hopper 3 .

[0061] The top cover 4 may be arranged outside the frame 1 to protect the entire screw press and various components in the frame 1 .

[0062] Optionally, the screw press further comprises:

[0063] A cleaning device 17 is disposed inside the top cover 4 and is used for cleaning the screen.

[0064] In some embodiments, the cleaning device 17 comprises:

[0065] A plurality of cleaning branch pipes are arranged at intervals inside the top cover 4;

[0066] Each of the cleaning branch pipes is provided with a plurality of spray ports 18 facing the screen, and the cleaning liquid is radially sprayed on the screen through the spray ports 18 .

[0067] In some embodiments, the plurality of cleaning branch pipes are evenly spaced and arranged inside the top cover.

[0068] Among them, if the viscosity of the processed material is high, the fixed screen 8 and the movable screen 9 may adhere to a certain amount of material after the operation. In order to ensure better squeezing efficiency and slurry permeability, a cleaning device 17 is designed inside the top cover 4 to achieve regular automatic cleaning. The spray port 18 is connected to the cleaning branch pipe by flange or thread connection, which is detachable and convenient for inspection and maintenance. The installation position of the cleaning device 17 should avoid the feed hopper 3, and the cleaning branch pipe can be reasonably designed according to the material conditions, such as Figure 2 As shown, the cleaning device 17 includes three cleaning branches, all installed on the upper part of the screen, and the spray heads of the two side branches should be installed in the direction of the pressing screw 10 to spray radially to ensure the cleaning effect. The cleaning device 17 is arranged inside the top cover 4 of the screw press to realize full automatic operation, regularly clean the pressing screen, and ensure high passability of the slurry.

[0069] In some embodiments, the pressing screw 10, the fixed screen 8, the movable screen 917, the cleaning device and the frame 1 are all flange-connected to facilitate maintenance and disassembly.

[0070] Optionally, the screw press further comprises:

[0071] The reclaimed water return port 13 is arranged in the middle or upper part of the slurry adjustment and sand removal hopper 12, and is used to input reclaimed water to dilute the slurry.

[0072] In some embodiments, the grey water enters the slurry adjustment and sand removal hopper at a predetermined angle.

[0073] Among them, the several times of the reclaimed water after subsequent treatment enters the slurry adjustment and sand removal hopper 12 at a certain angle through the reclaimed water return port 13 to dilute the squeezed slurry. The angle at which the reclaimed water return port is inserted into the slurry adjustment and sand removal hopper can be set as needed to ensure the internal slurry sand removal effect. The reclaimed water return port 13 uses the principles of gravity separation and density difference to control the water flow rate, so that the inorganic particles with large relative density sink and discharge, and the organic particles with small relative density are carried away with the water flow.

[0074] In some embodiments, all parts in contact with materials can be made of stainless steel. For example, the feed hopper 3, the fixed screen 8, the movable screen 9, the pressing screw 10, the back pressure device 5, the discharge port 7, the slurry mixing and sand removal hopper 12, the reclaimed water return port 13, the slurry outlet 14, the sand lifting screw 15, and the sand discharge port 16 are all made of stainless steel.

[0075] In some embodiments, the surface of the pressing screw 10 is sprayed with wear-resistant alloy steel.

[0076] Optionally, the screw press further comprises:

[0077] The controller is used to control at least one of the pressing screw 10 , the movable screen 9 , the back pressure device 5 , and the cleaning device 17 .

[0078] In some embodiments, the controller may be a CPU, a GPU or other chips with computing capabilities. In practical applications, the processor may be implemented by software, hardware, firmware or a combination thereof, and may use circuits, single or multiple application-specific integrated circuits (ASIC), digital signal processors (DSP), digital signal processing devices (DSPD), programmable logic devices (PLD), field programmable gate arrays (FPGA), central processing units (CPU), controllers, microcontrollers, and at least one of microprocessors.

[0079] The electric control signals of the pressing screw, mobile screen, back pressure device and cleaning device are all connected to the controller, and the whole process is automated.

[0080] In some embodiments, the controller can control the pressing screw 10 to realize forward and reverse rotation, and when the material is stuck or entangled, the reverse protection device is automatically performed.

[0081] Combination Figure 1 and Figure 2 , a screw press according to an embodiment of the present invention is described. Specifically, it includes:

[0082] The user puts the material into the material hopper 3, and the material enters the squeezing screw 10 through the material hopper 3. The controller can be used to control the driving motor 2 to drive the squeezing screw 10 to rotate clockwise (or reverse counterclockwise) to push the material. If the material is stuck or entangled during the process, the controller can be used to control the driving motor 2 to drive the squeezing screw 10 to rotate counterclockwise (or forward clockwise).

[0083] The squeezing screw 10 pushes the material forward, and the back pressure provided by the back pressure device 5 squeezes the material in the plug area 11 to achieve solid-liquid separation; according to the operation situation, steam or hot water can be used as a heating medium in the hollow shaft of the squeezing screw 10 to initially increase the temperature of the squeezing material and reduce the viscosity, so as to improve the squeezing efficiency and allow as many reusable components in the material as possible to enter the slurry, ensuring a high resource recovery rate.

[0084] The solid slag after squeezing is discharged from the discharge port 7, and the slurry falls into the slurry adjustment and sand removal hopper 12 at the bottom;

[0085] The several times more reclaimed water after subsequent treatment enters the slurry adjustment and sand removal hopper 12 at a certain angle through the reclaimed water return port 13 to dilute and adjust the squeezed slurry;

[0086] Heavy materials such as sand, shells, ceramics, glass, and metals in the slurry are discharged through the sand discharge port 16 via the sand lifting screw 15, thereby reducing the operating pressure and load of the subsequent processing equipment, extending the service life and maintenance cycle of the equipment, and the slurry after sand removal is discharged from the slurry outlet 14 to enter the subsequent processing process;

[0087] After the operation is completed, the fixed screen 8 and the movable screen 9 may adhere to certain materials. In order to ensure better squeezing efficiency and slurry permeability, a cleaning device 17 is designed inside the top cover 4 to achieve regular automatic cleaning to ensure higher slurry permeability and workshop environmental hygiene;

[0088] When the screw press is under inspection or maintenance and the internal material needs to be emptied, the movable screen 9 can be moved toward the feed hopper 3 through the controller. The material falls from the plug area 11 into the slurry mixing and sand removal hopper 12 under the pushing action of the pressing screw 10 and is discharged through the sand lifting screw 15.

[0089] Therefore, the screw press according to the embodiment of the present invention solves the problems of high moisture content of slag discharged from conventional equipment, manual cleaning of the screen, and the need for additional sand removal equipment for the slurry; and the material can be heated through the screw shaft to reduce the viscosity of the material, improve the solid-liquid separation efficiency, and ensure that most of the reusable materials enter the slurry, providing a guarantee for subsequent resource utilization.

[0090] According to the screw press of the embodiment of the present invention, a slurry adjustment and sand removal bucket is arranged at the lower part of the press to collect the squeezed slurry, and heavy materials such as gravel, shells, ceramics, glass, metals, etc. in the slurry are discharged through the bottom screw conveyor, thereby reducing the operating pressure and load of subsequent processing equipment, extending the service life and maintenance cycle, and the organic slurry after sand removal is discharged from the slurry outlet.

[0091] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0092] The above is only a specific embodiment of the present invention or an explanation of a specific embodiment. The protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A screw press, characterized in that: The screw press comprises: frame; A feed hopper is arranged above the frame and is used to feed materials; A pressing screw, arranged inside the frame and connected to the feed hopper, for pushing the material; A driving motor connected to the squeezing screw and used to drive the squeezing screw to move; A screen is coaxially arranged with the pressing screw and located between the pressing screw and the frame; A back pressure device, connected to the slag discharge end of the pressing screw, for applying back pressure to the material in the pressing screw to squeeze the material pushed by the pressing screw to obtain solid slag and slurry; A discharge port, arranged at the slag discharge end of the squeezing screw, for discharging the solid slag; A slurry mixing and sand removal hopper is arranged below the screen and is used to contain the slurry filtered by the screen; A sand lifting screw is connected to the slurry adjustment and sand removal hopper and is used to discharge heavy materials in the slurry through a sand discharge port provided at the end of the sand lifting screw; A slurry outlet is provided in the middle or upper part of the slurry adjustment and sand removal hopper, and is used to discharge the slurry after sand removal; A reclaimed water return port is provided in the middle or upper part of the slurry adjustment and sand removal hopper, and is used to input reclaimed water at a predetermined angle to dilute the slurry; The pressing screw comprises: There is a spiral blade area and a spiral blade-free area, the spiral blade area is close to the feed end of the pressing screw, and the spiral blade-free area is close to the slag discharge end of the pressing screw; The screen comprises a fixed screen and a movable screen, wherein the fixed screen corresponds to the region with spiral blades, and the movable screen corresponds to the region without spiral blades and can move along the pressing screw.

2. The screw press according to claim 1, characterized in that The pressing screw comprises a hollow shaft for introducing steam or hot water to preliminarily heat the material.

3. The screw press according to claim 1, characterized in that The diameter of the movable screen is greater than the diameter of the fixed screen.

4. The screw press according to claim 1, characterized in that The screw press also includes: A hydraulic device is connected to the back pressure device and is used to drive the back pressure device.

5. The screw press according to claim 1, characterized in that The screw press also includes: A top cover is arranged on the top of the screw press and is connected to the feed hopper.

6. The screw press according to claim 5, characterized in that The screw press also includes: A cleaning device is arranged inside the top cover and is used for cleaning the screen.

7. The screw press according to claim 6, characterized in that The cleaning device comprises: A plurality of cleaning branch pipes are respectively arranged at intervals inside the top cover; Each of the cleaning branch pipes is provided with a plurality of spray openings facing the screen, and the cleaning liquid is radially sprayed on the screen through the spray openings.

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