Combined convection type rinsing and selecting device for efficiently separating farmland plastic film residues
By combining turbulent shear cleaning and density gradient sorting with a combined convection rinsing and refining device, the problems of low separation efficiency and high energy consumption of waste plastic film were solved, achieving efficient and low-energy improvement of film purity and resource utilization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WUJIAQU LVJING AGRICULTURAL ENVIRONMENTAL PROTECTION TECHNOLOGY CO LTD
- Filing Date
- 2025-05-20
- Publication Date
- 2026-04-17
AI Technical Summary
In existing technologies, waste plastic film separation technology has low sorting efficiency, high impurity content, and problems such as high water consumption, high energy consumption and pollution, making it difficult to meet the requirements of high-value recycling and environmental protection.
A combined convection rinsing and refining device is adopted, which realizes a triple separation mechanism through turbulent shear cleaning, density gradient sorting and dynamic separation interface control, combined with PLC-HMI linkage control, thereby improving separation efficiency and reducing energy consumption.
It significantly improves membrane cleanliness, reduces impurity content, enhances the efficiency of resource utilization, reduces unit energy consumption by 28%, achieves product purity of over 95%, and achieves suspended solids separation efficiency of over 95%.
Smart Images
Figure CN224130226U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of agricultural machinery technology, and in particular to a combined convection rinsing and refining device for efficiently separating residual agricultural film. Background Technology
[0002] With the deepening of agricultural modernization, agricultural mulch film technology has become an indispensable element in agricultural production due to its significant effects in warming and conserving soil moisture, suppressing weeds, and increasing yields. However, the widespread use of mulch film has led to increasingly serious residue problems, creating a vicious cycle of "white pollution."
[0003] Current waste plastic film separation technologies suffer from low sorting efficiency and high impurity content. Existing technologies rely on manual sorting or simple mechanical sorting, resulting in low sorting efficiency and high labor intensity. For example, even after physical cleaning processes (such as water washing combined with roller friction), the impurity content of the plastic film still exceeds 10%, making it difficult to meet the requirements for high-value recycling. Although some equipment uses hydraulic flotation or sedimentation, due to flow field design defects, it cannot effectively separate impurities with similar densities (such as the small difference in Stokes number between straw and film), resulting in incomplete solid-liquid separation. In addition, existing processes generally suffer from high water and energy consumption. The water washing process consumes 5-15 m³ of water per wash. 3 The wastewater recycling process is slow and incomplete, leading to secondary pollution of sludge. Although chemical recycling can degrade mulch film, solvent residues can easily cause soil and water pollution, making it difficult to balance economic efficiency and environmental protection. Physical recycling technology is limited by impurity residues, resulting in a 30%-50% decrease in the mechanical properties of recycled particles, which is difficult to meet the needs of high-end product manufacturing and restricts the sustainable development of the industrial chain.
[0004] To address this issue, a combined convection rinsing and refining device for efficiently separating residual agricultural film is proposed. Utility Model Content
[0005] To overcome the above shortcomings, this utility model provides a combined convection rinsing and refining device for efficiently separating residual agricultural film, aiming to improve the problems of low sorting efficiency, incomplete impurity separation, high equipment energy consumption and poor cleaning effect in existing waste film separation technology.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: a combined convection rinsing and refining device for efficiently separating residual agricultural film, comprising a water tank, with material feeding working areas at both ends of the water tank, a material scooping working area on one side of the water tank, and a partial flushing area on the other side of the water tank. Several material feeders are evenly installed on the surface of the material feeding working area. A gradient dewatering unit is installed at one end of the water tank, and a gradient dewatering unit is installed on the other side of the surface of the material scooping working area. A scraper-type collection assembly is installed on the surface of the partial flushing area, a conical hopper is installed at the bottom of the partial flushing area, and a guide grid is installed in the middle of the partial flushing area.
[0007] As a further description of the above technical solution:
[0008] The surface of the feeder is provided with several blades.
[0009] As a further description of the above technical solution:
[0010] A pneumatic butterfly valve is installed at the bottom of the cone.
[0011] As a further description of the above technical solution:
[0012] A turbidity sensor is installed on the inner wall of the cone.
[0013] As a further description of the above technical solution:
[0014] The flow guide plate includes a corrugated screen and two inclined flow guide plates. The corrugated screen is installed in the middle of the local counter-current zone, and inclined flow guide plates are installed on both sides of the bottom end of the corrugated screen.
[0015] As a further description of the above technical solution:
[0016] The tilt angle of the inclined guide plate is 45°.
[0017] As a further description of the above technical solution:
[0018] A screw conveyor is installed on one side of the top of the localized counter-current zone.
[0019] As a further description of the above technical solution:
[0020] The surface of the stepped material retriever is provided with several chain rakes.
[0021] This utility model has the following beneficial effects:
[0022] 1. In this utility model, the device realizes a triple separation mechanism: turbulent shear cleaning, density gradient sorting and dynamic separation interface control, which reduces the membrane cleanliness index, improves the suspended solids separation efficiency, and significantly enhances the solid-liquid separation efficiency of subsequent resource recovery processes. The system realizes online monitoring of process parameters and energy efficiency optimization through PLC-HMI linkage control, reduces unit energy consumption, and the final product membrane purity reaches more than 95%.
[0023] 2. In this utility model, the device improves the residual film recovery rate and reduces system energy consumption through modular collaborative operation. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the structure of a combined convection rinsing and refining device for efficiently separating residual agricultural film proposed in this utility model;
[0025] Figure 2 This is a side view of a partial flushing zone of a combined convection rinsing and refining device for efficiently separating residual agricultural film proposed in this utility model;
[0026] Figure 3 This is a schematic diagram of the paddle structure of a combined convection rinsing and refining device for efficiently separating residual agricultural film proposed in this utility model.
[0027] Legend:
[0028] 1. Water tank; 2. Material feeding area; 3. Material scooping area; 4. Partial flushing area; 5. Material feeder; 6. Paddle; 7. Stepped material scooper; 8. Gradient dewatering unit; 9. Scraper collection assembly; 10. Screw conveyor; 11. Guide grid; 12. Corrugated screen; 13. Inclined guide plate; 14. Conical bucket; 15. Turbidity sensor; 16. Pneumatic butterfly valve; 17. Chain rake. Detailed Implementation
[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0030] Reference Figures 1-3This utility model provides an embodiment of a combined convection rinsing and refining device for efficiently separating residual agricultural film, comprising a water tank 1, which is designed as a rectangular flow channel. The material conveying system is connected to the inlet of the water tank 1 by a front-end chain conveyor. Material feeding working areas 2 are provided at both ends inside the water tank 1, a material scooping working area 3 is provided on one side inside the water tank 1, and a partial flushing area 4 is provided on the other side inside the water tank 1. Several material feeders 5 are evenly installed on the surface of the material feeding working area 2, and a clockwise rotation drive mechanism is configured and connected to a frequency converter. Several stepped scooping devices are installed on one side of the surface of the material scooping working area 3. The feeder 7 is equipped with a counterclockwise rotation drive mechanism and integrates a multi-stage lifting mechanism. The feeder 5 and the stepped feeder 7 are respectively connected to a planetary reducer through independent transmission shafts. A gradient dewatering unit 8 is installed at one end of the water tank 1, which includes three-stage centrifugal chambers connected in series. The pressure of each chamber increases by 0.3 MPa. The hot air drying unit uses an annular air distributor. The film falls from the feeder onto the inclined plate into the water tank 1 and undergoes a secondary wash in the feeder area. After the secondary wash, it enters the gradient dewatering unit 8. A scraper-type collection component 9 is installed on the surface of the local flushing zone 4 to remove particles with a density <1.0 g / cm³. 3 The scum layer has a cone hopper 14 installed at the bottom of the local flushing zone 4, where high-density particles settle and are collected. A flow guide plate 11 is installed in the middle of the local flushing zone 4 to guide the settling of high-density particles.
[0031] Reference Figure 3 The surface of the feeder 5 is provided with several blades 6, and the surface is covered with a 2mm wear-resistant ceramic coating. The spacing of the blades 6 is gradient along the axial direction, and the tilt angle of the blades 6 can be adjusted from 15° to 45°. The tangential fluid shear force generated by the blades 6 of the feeder 5 and the reverse hydraulic gradient of the feeder form a local counter-current zone 4 with a turbulence intensity of 3-5m / s, thereby achieving solid-liquid separation of the material with a hydraulic residence time of 120-180 seconds.
[0032] Reference Figure 2 A pneumatic butterfly valve 16 is installed at the bottom of the cone 14. The pneumatic butterfly valve 16 at the bottom of the cone 14 is used for periodic discharge of gases with a density > 2.5 g / cm³. 3 The settled particles.
[0033] Reference Figure 2 The inner wall of the cone 14 is equipped with a turbidity sensor 15, which can detect the density of particulate matter inside the cone 14 so that it can be removed in a timely manner.
[0034] Reference Figure 2The flow guide plate 11 includes a corrugated screen 12 and two inclined flow guide plates 13. The corrugated screen 12 is installed in the middle of the local counter-current zone 4. The screen aperture is 5mm. Inclined flow guide plates 13 are installed on both sides of the bottom end of the corrugated screen 12. The double-layer design guides the light impurities to float and the heavy particles to settle.
[0035] Reference Figure 2 The inclined guide plate 13 has an inclination angle of 45° and is used to guide heavy particles into the cone hopper 14 for collection.
[0036] Reference Figure 2 A screw conveyor 10 is installed on one side of the top of the local flushing zone 4. The scum layer formed by the floating impurities is collected by the scraper and discharged through the lateral screw conveyor 10.
[0037] Reference Figure 1 The surface of the stepped material scoop 7 is equipped with several chain rakes 17. The chain rakes 17 adopt a staggered arrangement of spring teeth, which are arranged in a stepped manner and can roll in the opposite direction. The spring teeth form an angle of 5-15° with the horizontal plane. The reverse rolling is used to achieve the initial separation of the mulch film and impurities.
[0038] Working Principle: The pre-sorted film material is conveyed into a combined convection rinsing and refining device via a conveying mechanism. This device adopts a tank-type structure, and its core component includes 5 axially distributed feeders. In the rinsing and separation process section, a dynamic counter-current flow field is constructed by setting up counter-rotating feeders 5 and a material catcher mechanism to achieve efficient material sorting. Specifically, the axially distributed feeders 5 rotate clockwise, and their blades 6 apply tangential fluid shear force to the water, driving the film-containing material to migrate towards the central axial region of the device, i.e., the local counter-current zone 4; at the same time, the stepped material catcher array 7 runs counter-clockwise, generating a reverse hydraulic gradient through a multi-stage lifting mechanism. The overlapping of two opposing flow fields creates a localized countercurrent zone with turbulence intensity of 3-5 m / s4, significantly extending the hydraulic residence time of the material to 120-180 seconds. This promotes the peeling of deposits on the membrane surface and improves solid-liquid separation efficiency. From a fluid dynamics perspective, the kinetic energy dissipation induced by the countercurrent effect enables rapid separation of lightweight impurities such as straw with a Stokes number less than 0.1 from the membrane. In density-based sorting mechanisms, impurities with a density less than 1.0 g / cm2... 3 Plant fibers, under the Bernoulli effect, accumulate in the localized flushing zone 4 on the surface of the water tank 1, forming a scum layer approximately 15-20 cm thick, which can be continuously removed by the scraper-type collection component 9; while the density is greater than 2.5 g / cm³ 3High-density inorganic particles such as slag and soil accumulate at the bottom of the tank under gravity settling at a final settling velocity of 0.5-1.2 cm / s, with periodic solid phase discharge achieved in conjunction with the pneumatic butterfly valve 16. This process design reduces the impurity content of the membrane product to below 0.3%, and the unit processing energy consumption is reduced by 28% compared to traditional processes. The device integrates an intelligent control module, which monitors the concentration of suspended solids in the water in real time through an immersion turbidity sensor 15 (detection accuracy ±5 NTU), and dynamically adjusts the rotation speed of the feeder 5 (0-120 r / min stepless speed regulation) and the water circulation rate (5-15 m³ / min). 3 The film, after being selected in the material collection area 3, is transported to the slag discharge and film washing optimization system. Five sets of feeders rotate continuously in the water, driving the film backward. The feeders are set to rotate clockwise, with the speed adjusted in real-time by a frequency converter, ranging from 0-120 r / min. During this process, the slag and micron-sized particulate impurities adhering to the film surface are fully removed under the secondary turbulent washing action and concentrated in the slag discharge area at the bottom of the tank by gravity settling. After rinsing, the film undergoes a primary dewatering stage via an end-feeding centrifugal dryer. This equipment has a built-in high-speed rotating centrifugal drum, driven by a frequency converter motor and a belt drive system. After the material is automatically fed into the centrifugal drying chamber by a screw propulsion system, under the action of centrifugal force, free water and solid material move in opposite directions. Water is forced out through the gaps in the wall of the centrifugal drum, while the solid material continues to propel along the axial direction. In the primary dehydration stage, the material is subjected to centrifugal acceleration generated by a rotation speed of ≥1000 r / min within the spin dryer, achieving rapid removal of surface free water. The secondary dehydration stage further squeezes out internal pore water by optimizing the flow guiding structure on the inner wall of the spin dryer and utilizing the material's own accumulation pressure. The vibration-assisted system effectively disrupts capillary action between materials, reducing water retention, and ultimately achieving a dehydration rate of over 50%. The dehydrated material is automatically discharged via a screw conveyor structure, with a processing capacity of 300-400 kg / h, for subsequent production processes. In the deep dehydration stage, a horizontal multi-stage gradient spin dryer unit is used. Through progressive pressurization (0.2-1.2 MPa) combined with a hot air convection drying module (80-120℃), the crystallinity of the thin film is controlled and residual moisture is evaporated, removing 80-90% of the moisture. The final processing stage features a fully automated metering and packaging system, integrating high-precision weighing sensors (±0.5% FS) and a vacuum moisture-proof sealing unit to form standardized finished rolls. The entire system mainly includes a combined convection rinsing and refining device and a slag removal and film washing optimization system. Through turbulent shear cleaning, density gradient sorting, and dynamic separation interface control, the film cleanliness index (surface residue) is improved from an initial 3.5-5.2 g / m³. 2 Reduced to 0.8-1.2 g / m 2 The suspended solids separation efficiency reaches over 95%, enabling online monitoring of process parameters and energy efficiency optimization. The unit energy consumption is reduced by more than 35% compared to traditional processes, with a system energy consumption of ≤15kWh / t.
[0039] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A combined counterflow rinsing and cleaning device for efficiently separating residual agricultural film, comprising a water tank (1), characterized in that: Both ends of the water tank (1) are provided with material feeding working areas (2), one side of the water tank (1) is provided with material scooping working area (3), the other side of the water tank (1) is provided with a local flushing area (4), a number of material feeders (5) are evenly installed on the surface of the material feeding working area (2), a number of stepped material scoopers (7) are installed on one side of the surface of the material scooping working area (3), a gradient dewatering unit (8) is installed at one end of the water tank (1), a scraper-type collection component (9) is installed on the surface of the local flushing area (4), a cone bucket (14) is installed at the bottom of the local flushing area (4), and a guide grid plate (11) is installed in the middle of the local flushing area (4).
2. The combined counterflow rinsing and cleaning device according to claim 1, wherein: The surface of the feeder (5) is provided with several blades (6).
3. The combined counterflow rinsing and cleaning device according to claim 1, wherein: A pneumatic butterfly valve (16) is installed at the bottom of the cone (14).
4. The combined counterflow rinsing and cleaning device according to claim 3, characterized in that: A turbidity sensor (15) is installed on the inner wall of the cone (14).
5. The combined counterflow rinsing and cleaning device according to claim 1, wherein: The flow guide plate (11) includes a corrugated screen (12) and two inclined flow guide plates (13). The corrugated screen (12) is installed in the middle of the local counter-current zone (4), and inclined flow guide plates (13) are installed on both sides of the bottom end of the corrugated screen (12).
6. The combined counterflow rinsing and cleaning device according to claim 5, wherein: The tilt angle of the inclined guide plate (13) is 45°.
7. The combined counterflow rinsing and cleaning device according to claim 1, wherein: A screw conveyor (10) is installed on one side of the top of the local counter-current zone (4).
8. The combined convection rinsing and refining device for efficiently separating residual agricultural film as described in claim 1, characterized in that: The surface of the stepped material scoop (7) is provided with several chain rakes (17).