A tannin extraction residue filter pressing device and a method of using the same

Abstract

The application discloses a tannin extract residue filter-pressing device and a use method thereof, relates to the technical field of tannin processing, and comprises a base, a mounting frame fixedly connected to the base, and a filter press fixedly penetrating through the mounting frame. The filter press comprises a filter box fixedly penetrating through the mounting frame, a filter plate fixedly connected in the filter box, and a pressing plate movably arranged in the filter box. A feeding pipe is communicated with the upper half of the filter box. A driving mechanism is arranged on the filter press and used for driving the filter press to perform filter-pressing treatment on residues. A discharging device is arranged at the bottom of the filter press and comprises a sealing cover mechanism and a cleaning mechanism. The sliding rod penetrates through the pressing plate and filter cloth, the filter cake can be conveniently taken out, the discharging port and the liquid outlet pipe are integrated on the cover plate, the structure can be conveniently overhauled, the discharged filter cake and residues are few, the cleaning time is reduced, the overall working efficiency is improved, the moving plate can not only assist in discharging the filter cake from the filter box but also clean the residues on the filter plate, and the overall coherence of the equipment is improved.

Description

Technical Field

[0001] This invention relates to the field of tannin processing technology, specifically to a tannin extraction residue pressure filter device and its usage method. Background Technology

[0002] Tannin is a core biomass material in the forest chemical industry. It is prepared from forestry byproducts such as tree bark and fruit shells through hot water extraction to remove tannins. It is widely used in various industries, including leather tanning, water treatment flocculation, wood adhesives, and oilfield chemicals, possessing both economic and ecological benefits. During the tannin extraction process, a large amount of solid residue is generated after the extraction, mainly composed of cellulose, lignin, and hemicellulose, with residual small amounts of tannins and phenolic substances. The initial moisture content is typically 60%–80%, resulting in a high-moisture paste with poor flowability, making it difficult to directly transport and utilize as a resource.

[0003] Efficient dehydration of tannin extraction residue is a key step in the production process. On one hand, the significantly reduced moisture content of the dehydrated residue allows for the formation of a well-formed filter cake, substantially reducing storage and transportation costs. This facilitates subsequent resource utilization, such as blending with biomass fuel, preparing activated carbon, or manufacturing engineered wood products, aligning with the circular economy development direction of forestry chemical industry, which aims to "turn waste into treasure." On the other hand, the waste liquid extracted during pressing contains residual tannin components, which can be recycled back to the extraction process, improving the comprehensive utilization rate of raw materials and reducing production losses. Currently, the industry commonly uses plate and frame filter presses as the core equipment for residue dehydration, relying on the squeezing action of filter plates and pressure plates to achieve solid-liquid separation. However, its practical application still has several technical shortcomings.

[0004] First, traditional filter presses mostly employ a structure with built-in drive rods along the pressing direction. These drive rods directly penetrate the pressure plate and filter cloth into the filter chamber. After pressing, the rods become embedded in the filter cake, easily tearing the cake during unloading and generating a large amount of debris. This not only results in poor filter cake integrity but also causes scattered debris to accumulate in equipment gaps and on the workshop floor, significantly increasing manual cleaning workload and extending the turnaround time for each batch. Second, fine residue easily adheres to the surfaces of the filter plates and filter cloth. Most existing equipment lacks an automatic cleaning mechanism, requiring manual cleaning of the filter plate surface after each batch unloading. This leads to low continuous production efficiency, and uneven manual cleaning can easily cause partial damage to the filter cloth, increasing consumable costs.

[0005] Furthermore, the drainage pipes of existing filter press equipment are mostly scattered on the side walls and bottom of the filter box, with numerous and dispersed sealing interfaces. When leaks or blockages occur, the main structure of the filter box must be disassembled for repair, resulting in high maintenance difficulty and long downtime. The unloading method is mostly an open unloading system where the filter plates are pulled open laterally. The filter cake is prone to breakage during free fall, and material is easily splashed and leaked, worsening the workshop working environment. At the same time, unloading, filtration, and drainage processes are mostly controlled by independent drive components, resulting in complex equipment structures, numerous power points, and high failure rates and maintenance costs. To address these industry pain points, there is an urgent need to develop a new type of tannin residue filter press that features convenient unloading, good filter cake integrity, automatic filtration, and easy maintenance, in order to improve the overall automation level and economic efficiency of tannin production. Summary of the Invention

[0006] The purpose of this invention is to provide a tannin extraction residue pressure filter device and its usage method to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a tannin extraction residue filter press, comprising a base, a mounting frame fixedly connected to the base, a filter press fixedly passing through the mounting frame, a filter box fixedly passing through the mounting frame, a filter plate fixedly connected inside the filter box, a pressure plate movably disposed inside the filter box, a feed pipe connected to the upper half of the filter box, a drive mechanism on the filter press for driving the filter press to filter the residue, a feeding device at the bottom of the filter press, the feeding device comprising a sealing mechanism and a cleaning mechanism, a draining mechanism connected to the sealing mechanism for draining the liquid filtered out of the filter press; wherein:

[0008] The sealing mechanism is used to move and close the bottom opening of the filter box;

[0009] The cleaning mechanism is used to push the filter cake downwards out of the filter box and to clean the residue on the filter plate.

[0010] Furthermore, the sealing mechanism includes a cover plate that moves to seal the bottom opening of the filter box, and a telescopic push rod for pushing the cover plate to move and seal is fixedly connected at the center of the bottom of the cover plate.

[0011] Furthermore, the cleaning mechanism includes connecting rods on both sides of the sealing mechanism. A bracket is connected to the top of the connecting rod, and a sliding rod is connected to the bottom of the bracket. The bottom of the sliding rod is movably inserted into the through hole and fixedly connected to a moving plate for pushing the filter cake down and cleaning the filter plate.

[0012] Furthermore, the discharge mechanism includes a discharge port on the sealing mechanism, the bottom end of the discharge port is connected to a discharge pipe, the outer end of the discharge pipe is connected to a pipeline, and the free end of the pipeline is connected to a storage tank.

[0013] Furthermore, the driving mechanism includes a bracket mounted on the filter box, on which a telescopic push rod 2 is installed. The extended end of the telescopic push rod 2 is connected to a slide rod. The end of the slide rod away from the telescopic push rod 2 moves through a sliding seat and is fixedly connected to a sliding block for driving the pressure plate to move and press the filter.

[0014] Furthermore, the cover plate is larger than the bottom opening of the filter box, the top surface of the cover plate is provided with a sealing layer, and one bottom end of the telescopic push rod is fixedly connected to the base plate.

[0015] Furthermore, the two sets of linkage rods are symmetrically arranged on the side wall of the cover plate, the number of sliding rods is equal to the number of filter plates, the through hole is opened at the top of the filter box, the moving plate is wrapped with a sealing layer, and a brush is provided on the side wall of the moving plate near the filter plate.

[0016] Furthermore, the discharge port is located on a cover plate on one side of the filter plate, the number of discharge ports is equal to the number of filter plates, the sum of the height of the discharge port and the height of the pipe is less than the height of the cover plate, the pipe is arranged inside the cover plate, the length of the pipe is less than the length of the cover plate, and the pipe is a flexible hose.

[0017] Furthermore, the bracket has an L-shaped structure, the telescopic push rod is used to drive the slide rod to move back and forth, the sliding seat is a rectangular structure with a groove on one side, the open end of the sliding seat is connected to the side wall of the filter box, the sliding block is slidably connected to the sliding seat, and one end of the sliding block is fixedly connected to the side wall of the pressure plate.

[0018] The present invention also provides a method for using a tannin extraction residue filter press, comprising the following steps:

[0019] S1. Equipment Pre-inspection and Station Reset: Before the filter press operation, perform a pre-inspection of the filter press device and reset each component to its station position; control the telescopic push rod one to fully extend, so that the cover plate is sealed and positioned against the bottom of the filter box; control the telescopic push rod two to fully retract, so that the pressure plate returns to its initial position on the side of the filter chamber; at the same time, control the moving plate of the cleaning mechanism to return to the standby position at the top of the filter chamber, without occupying the filter press space or interfering with the movement of the pressure plate; check that the feed pipe is unobstructed and free from blockages; check that the connection between the liquid outlet pipe and the liquid storage tank is sealed and intact; straighten the flexible pipe to avoid bending and squeezing, and ensure that the discharge path is unobstructed; visually inspect that the filter cloth on the surface of the filter plate is flat and intact, and that there is no jamming or foreign matter in the gaps between the sliding parts; after completing all pre-inspections, start the equipment control system to put the equipment into the standby feeding state;

[0020] S2. Constant Pressure Feeding and Filling: The pretreated tannin extraction residue is pumped into the filter box through the feed pipe using a slurry pump, so that the material is evenly filled into the filter chamber space between the pressure plate and the filter plate. During the feeding process, the output pressure of the slurry pump is controlled at 0.2~0.3MPa, and a low-speed, slow injection method is adopted to avoid material impact causing filter cloth displacement and damage. At the same time, the telescopic push rod 2 is controlled to make small-stroke reciprocating micro-movements, which causes slight disturbance of the material, so as to achieve uniform material distribution and prevent local material accumulation. When the filter chamber is completely filled with material and the pressure in the feed pipe rises slightly and steadily, the feeding is stopped and the feed pipe valve is closed to complete the material filling.

[0021] S3. Staged Pressure Filtration and Filtrate Collection: After feeding, activate the telescopic push rod two to move the slide bar horizontally at low speed. This, along with the sliding block, drives the pressure plate slowly towards the filter plate, performing staged pressure pressing on the residue in the filter chamber. First, perform low-pressure pre-pressing, maintaining the pressing pressure at 0.5 MPa for 3-5 minutes to initially dehydrate and shape the residue, removing most of the free water. Then, perform high-pressure holding, gradually increasing the pressure to 1.2-1.5 MPa and holding for 8-12 minutes to remove capillary water from the residue and reduce the moisture content of the filter cake. During the filtration process, the filtrate flows downwards along the filter plate surface under gravity into the cover plate's discharge port, and then through the outlet pipe and flexible pipeline into the storage tank for temporary storage. Monitor the filtrate flow rate in real time. When the filtrate flow rate significantly decreases and the filter cake formation stabilizes, the filtration process is complete.

[0022] S4. Synchronous Unloading and Filter Plate Cleaning: After the filtration process is completed, control the telescopic push rod two to retract slowly at low speed, driving the pressure plate back to its initial position smoothly, so that the pressure plate and filter cake are completely separated, avoiding the negative pressure adsorption caused by rapid plate retraction that could lead to filter cake breakage; then control the telescopic push rod one to retract at a uniform speed, driving the cover plate to move vertically downwards, and the filter cake relies on its own gravity to descend synchronously with the cover plate and detach from the filter chamber body; during the descent of the cover plate, the linkage rods on both sides drive the support and sliding rod to descend synchronously, driving the moving plate to slide downwards along the filter chamber, and the lower end face of the moving plate assists in pushing the filter cake completely out of the filter box, while the brush on the side of the moving plate sweeps the surface of the filter plate at a uniform speed to remove the fine residual residue attached to the filter cloth surface; after the cover plate is lowered to the lowest position, the complete filter cake on the cover plate is removed by the transfer tool, completing the unloading and filter plate cleaning operation;

[0023] S5. Equipment Reset and Cycle Preparation: After unloading and cleaning, control the telescopic push rod to extend at a uniform speed, pushing the cover plate upwards to reset, so that the cover plate re-seals and fits against the bottom of the filter box; at the same time, the linkage rod drives the bracket, sliding rod and moving plate to rise synchronously, so that the moving plate returns to the initial standby position at the top of the filter chamber; after confirming that all moving parts of the equipment are fully reset, and that the sealing performance and pipeline status are normal, the next round of feeding and filtration cycle can begin; after each shift of production, rinse the surface of the cover plate and the brush of the moving plate with clean water to remove residual residue; regularly check the wear of the equipment seals and the integrity of the filter cloth, and replace worn parts in a timely manner to ensure stable operation of the equipment.

[0024] Compared with the prior art, the technical advantages of the present invention are as follows:

[0025] 1. This invention places the drive mechanism entirely on the side of the filter box. The sliding seat and sliding block work together to drive the pressure plate horizontally. The drive rod remains outside the filter chamber throughout the entire process, eliminating the need to penetrate the pressure plate and filter cloth along the pressing direction. During filtration, there is no interference from transmission rods inside the filter chamber, resulting in uniform pressure on the residue and a complete and dense filter cake. During unloading, there is no need to overcome the resistance of the rods; the filter cake can be removed as a whole, significantly reducing the breakage rate, minimizing debris generation, and lowering the labor and time costs of on-site cleaning. Simultaneously, this structure avoids repeated friction between the transmission rods and the filter cloth, effectively extending the filter cloth's service life, reducing the frequency of consumable replacements, and lowering long-term maintenance costs.

[0026] 2. This invention integrates the feed inlet and liquid outlet pipe entirely within the cover plate, forming a unified functional module with the sealing structure. When blockages or leaks occur in the drainage pipe, the entire drainage system can be inspected, cleared, and seals replaced simply by lowering the cover plate, eliminating the need to disassemble the main filter box structure and significantly reducing downtime. Simultaneously, a sealing layer is provided on the top surface of the cover plate, which fits tightly against the bottom opening of the filter box when raised to the working position, forming a reliable surface-contact static seal. This eliminates the risk of leakage at the bottom of the filter chamber during filtration, ensuring stable pressing pressure output and improving solid-liquid separation and overall dewatering efficiency.

[0027] 3. This invention employs a bottom lifting and unloading method. After filtration, the cover plate moves downwards at a uniform speed along with the telescopic push rod, and the filter cake falls smoothly and synchronously with the cover plate under its own gravity. Compared to the traditional side-opening unloading method, the filter cake is not subjected to the tearing force generated by the filter plate being pulled apart. The force is even and the release process is smooth, resulting in a high degree of filter cake integrity and minimal residue generation. This reduces the workload of cleaning up scattered residue around the equipment and improves the turnover efficiency of single-batch production. At the same time, the high integrity of the filter cake makes it easier for subsequent transportation, stacking, and resource recovery, reducing the labor costs and material losses of secondary processing.

[0028] 4. The cleaning mechanism of this invention is rigidly linked to the cover plate via a connecting rod, sharing the same lifting drive source. As the cover plate moves downwards to unload the material, the connecting rod simultaneously drives the support and sliding rod to move the moving plate downwards. The moving plate applies a downward thrust to the filter cake through its lower end surface, helping the filter cake overcome friction with the filter chamber sidewalls and smoothly detach. Simultaneously, the side brushes sweep along the filter plate surface at a uniform speed, automatically removing fine residue adhering to the filter cloth surface through mechanical friction. The unloading and cleaning processes are completed simultaneously, eliminating the need for a separate cleaning drive device, reducing the number of power components, simplifying the equipment structure, and eliminating the need for additional downtime for cleaning, effectively shortening the single-cycle cycle and improving continuous production efficiency.

[0029] 5. In this invention, the entire filtration process is conducted in a closed space. The pressure plate, filter plate, and cover plate together form a closed filter chamber. The tannin waste liquid generated during pressing flows directly into the outlet pipe through the discharge port on the cover plate, and is then transported to the storage tank for temporary storage via a flexible, closed-loop pipeline. This system avoids the loss of tannin components caused by waste liquid splashing and leakage, improves the recovery efficiency of residual tannin in the residue, and enhances the comprehensive utilization rate of raw materials and tannin yield. At the same time, the closed structure effectively reduces the diffusion of residue dust and waste liquid odors during production, improves the workshop working environment, reduces the management costs of clean production, and meets the environmental protection standards and clean production requirements of forestry chemical production. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the present invention;

[0031] Figure 2 This is a schematic diagram of the structure of the filter press in this invention;

[0032] Figure 3 This is a schematic diagram of the structure of the feeding device in this invention;

[0033] Figure 4 This is a schematic diagram of the sealing mechanism in this invention;

[0034] Figure 5 This is a schematic diagram of the cleaning mechanism in this invention;

[0035] Figure 6 This is a schematic diagram of the structure of the drainage mechanism in this invention;

[0036] Figure 7 This is a schematic diagram of the drive mechanism in this invention.

[0037] In the diagram: 1. Base; 2. Mounting frame; 3. Filter press; 4. Drive mechanism; 5. Feeding equipment; 6. Drainage mechanism;

[0038] 41. Bracket; 42. Telescopic push rod II; 43. Slide rod; 44. Slide seat; 45. Slide block;

[0039] 510. Sealing mechanism; 511. Cover plate; 512. Telescopic push rod one;

[0040] 520. Cleaning mechanism; 521. Linking rod; 522. Bracket; 523. Sliding rod; 524. Through hole; 525. Moving plate;

[0041] 61. Feed inlet; 62. Liquid outlet pipe; 63. Pipeline; 64. Storage tank. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] See Figure 1-7 A tannin extraction residue filter press includes a base 1, a mounting frame 2 fixedly connected to the base 1, a filter press 3 fixedly passing through the mounting frame 2, and a through hole at the center of the mounting frame 2 having a length greater than the maximum distance between two sets of connecting rods 521, allowing the connecting rods 521 to rise and fall at the through hole of the mounting frame. A feeding device 5 is provided at the bottom of the filter press 3, including a sealing mechanism 510 and a cleaning mechanism 520. The filter press 3 includes a filter box fixedly passing through the mounting frame 2, a filter plate fixedly connected inside the filter box, and filter cloth wrapped on the filter plate. A pressure plate is movable inside the filter box. A feed pipe is connected to the upper half of the filter box. A drive mechanism 4 is provided on the filter press 3, used to drive the filter press 3 to perform filter pressing treatment on the residue. The drive mechanism 4 includes a bracket mounted on the filter box. 41. A telescopic push rod 42 is installed on the bracket 41. The extended end of the telescopic push rod 42 is connected to a slide rod 43. The end of the slide rod 43 away from the telescopic push rod 42 moves through the sliding seat 44 and is fixedly connected to a sliding block 45 for driving the pressure plate to move and filter. The bracket 41 has an L-shaped structure. The telescopic push rod 42 is used to drive the slide rod 43 to move back and forth. The cross-sectional area of ​​the slide rod 43 is close to the cross-sectional area of ​​the groove of the sliding seat 44, so that the slide rod 43 slides in the groove of the sliding seat 44 while reducing the entry of residue into the gap. The sliding seat 44 is a rectangular structure with a groove on one side. The groove can be set as a semi-cylindrical structure. The open end of the sliding seat 44 is connected to the side wall of the filter box. The sliding block 45 is slidably connected to the sliding seat 44. One end of the sliding block 45 is fixedly connected to the side wall of the pressure plate.

[0044] The residue extracted from tannin is pumped into the feed pipe and enters the gap between the filter plate and the pressure plate in the filter box. The second telescopic push rod 42 is driven, which pushes the slide rod 43 to move. The slide rod 43 drives the sliding block 45 and the pressure plate to move. The pressure plate moves and compresses the liquid in the residue extracted from tannin, which passes through the filter plate (the residue that does not pass through the filter plate is compressed into a filter cake). The liquid flows downward into the discharge port 61, preventing the slide rod from penetrating the pressure plate and the filter cloth, which facilitates the subsequent removal of the filter cake.

[0045] A draining mechanism 6 is connected to the capping mechanism 510. The draining mechanism 6 is used to drain the liquid filtered out of the filter press 3. The draining mechanism 6 includes a discharge port 61 opened on the capping mechanism 510. The bottom end of the discharge port 61 is connected to the liquid outlet pipe 62. The outer end of the liquid outlet pipe 62 is connected to the pipe 63. The free end of the pipe 63 is connected to the liquid storage tank 64. The discharge port 61 is located on the cover plate 511 on one side of the filter plate. The number of discharge ports 61 is equal to the number of filter plates. The sum of the height of the discharge port 611 and the height of the pipe 63 is less than the height of the cover plate 511. The pipe 63 is arranged inside the cover plate 511. The length of the pipe 63 is less than the length of the cover plate 511. The pipe 63 is a flexible hose.

[0046] After entering the discharge port 61, the liquid flows into the discharge pipe 62, then into the pipe 63 through the discharge pipe 62, and finally into the storage tank 64 for temporary storage, completing the liquid discharge work. The discharge port 61 and the discharge pipe 62 are integrated on the cover plate 511, which facilitates the maintenance of this structure.

[0047] The sealing mechanism 510 is used to move and seal the bottom opening of the filter box. The sealing mechanism 510 includes a cover plate 511 that moves to seal the bottom opening of the filter box. A telescopic push rod 512 for pushing the cover plate 511 to move and seal is fixedly connected at the bottom center of the cover plate 511. The size of the cover plate 511 is larger than the size of the bottom opening of the filter box. A sealing layer is provided on the top surface of the cover plate 511. The bottom end of the telescopic push rod 512 is fixedly connected to the base plate 1.

[0048] The retraction of the telescopic push rod 42 separates the pressure plate from the filter cake, driving the telescopic push rod 512. The retraction of the telescopic push rod 512 causes the cover plate 511 to move down and separate from the filter box. The filter cake moves down with the cover plate 511 to the bottom of the filter box, resulting in less filter cake debris and reduced cleaning time, thereby improving overall work efficiency.

[0049] The cleaning mechanism 520 is used to push the filter cake downwards out of the filter box and to clean the residue on the filter plate. The cleaning mechanism 520 includes connecting rods 521 on both sides of the sealing mechanism 510. The top of the connecting rod 521 is connected to a bracket 522, and the bottom of the bracket 522 is connected to a sliding rod 523. The bottom of the sliding rod 523 moves into the through hole 524 and is fixedly connected to a moving plate 525 for pushing the filter cake downwards and cleaning the filter plate. Two sets of connecting rods 521 are symmetrically arranged on the side wall of the cover plate 511. The number of sliding rods 523 is equal to the number of filter plates. The through hole 524 is opened at the top of the filter box and has a T-shaped structure. The moving plate 525 is covered with a sealing layer and has a brush on the side wall of the moving plate 525 near the filter plate.

[0050] As the cover plate 511 moves downward, it simultaneously drives the connecting rod 521 to move. The connecting rod 521 drives the bracket 522 to move downward. The bracket 522 pushes the sliding rod 523 and the moving plate 525 to move downward. The moving plate 525 pushes the filter cake downward and away from the filter box. The end of the moving plate 525 with the brush slides and rubs against the filter plate to sweep and clean the filter plate. The moving plate 525 not only assists in the discharge of the filter cake from the filter box, but also cleans the residue on the filter plate, improving the overall continuity of the equipment.

[0051] Technical principle of the invention:

[0052] This tannin extraction residue pressure filter is based on the integrated design principle of "side-mounted linear drive pressing + bottom sealed drainage + linkage unloading and cleaning". Through the coordinated cooperation of mechanical transmission and gravity flow field, it realizes efficient solid-liquid separation and automated unloading and cleaning of tannin residue. The overall technical principle can be divided into three core parts: pressure filter drive, sealed drainage, and linkage unloading and cleaning.

[0053] The filter press drive principle adopts a side-mounted linear transmission layout, using the second telescopic push rod as the power output source. It is stably fixed to the outer wall of the filter box via an L-shaped bracket, avoiding the power components occupying internal space within the filter chamber. The telescopic movement of the second telescopic push rod is converted into the horizontal linear displacement of the sliding rod. The sliding rod slides directionally along the built-in groove of the sliding seat, thereby driving the sliding block and pressure plate to perform horizontal reciprocating motion within the filter chamber. The sliding seat is connected to the side wall of the filter box, and the sliding block fits tightly with the inner wall of the groove, ensuring both the linear accuracy of the transmission and forming a dynamic sealing barrier on the side wall of the filter chamber, preventing residue and debris from entering the transmission gap and causing jamming. During filter press operation, the moving plate of the cleaning mechanism remains at the top of the filter chamber, not occupying the filter press space or interfering with the horizontal movement of the pressure plate. When the pressure plate moves towards the filter plate, it applies continuous extrusion pressure to the tannin residue in the filter chamber, causing the liquid phase in the residue to pass through the filter cloth medium on the surface of the filter plate under the action of the pressure gradient. The solid residue is trapped between the pressure plate and the filter plate, gradually compressing to form a dense filter cake, completing the solid-liquid separation process. This side-mounted transmission principle structurally avoids the problem of traditional built-in drive rods penetrating the filter cake, thus ensuring the integrity of the filter cake from the source.

[0054] The sealing and drainage principle employs a bottom-lifting static sealing structure, using a telescopic push rod as the lifting power to drive the cover plate in a vertical lifting motion. When the cover plate rises to the working position, the sealing layer on the top surface tightly adheres to the edge of the bottom opening of the filter box, forming a surface-contact static seal. This provides a sealed bottom support for the filtration process and withstands the pressure load during pressing. The filtrate produced during pressing flows downwards along the vertically arranged filter plate surface under its own gravity, directly flowing into the discharge port on the cover plate directly below the corresponding filter plate. After being collected through the outlet pipe, it is transported to the storage tank for temporary storage via a flexible pipeline. The drainage channels are all integrated inside the cover plate, relying on gravity to achieve gravity-fed filtrate transport without the need for additional pumping power. The flexible pipeline adapts to the lifting and lowering displacement of the cover plate, maintaining a sealed pipeline throughout the process, reducing filtrate loss and leakage risks.

[0055] The linkage unloading and filtration principle adopts a rigid synchronous linkage design, with the cleaning mechanism and the capping mechanism sharing the same drive source. The linkage rods are symmetrically fixed on both sides of the cover plate, and their tops are connected to multiple sets of sliding rods via a transverse bracket. The sliding rods pass through the through-holes at the top of the filter box and are fixedly connected to the moving plate, forming a rigid transmission chain of cover plate-linkage rod-bracket-sliding rod-moving plate. The moving plate is wrapped with a sealing layer, which can seal the top gap when the filter press is idle, preventing material from overflowing into the through-hole. When the telescopic push rod moves the cover plate down to unload, the power is synchronously transmitted downwards through the linkage rods, driving the sliding rods to slide vertically down along the through-holes, and causing the moving plate to move synchronously downwards within the filter chamber. On one hand, the moving plate applies a downward thrust to the filter cake through contact with its lower end face, helping the filter cake overcome the friction with the side wall of the filter chamber and smoothly exit the filter chamber; on the other hand, the brushes on the side of the moving plate form sliding friction with the filter plate surface, removing fine residues adhering to the filter cloth surface through the mechanical action of uniform-speed brushing, thus achieving simultaneous completion of the unloading and filter plate cleaning processes. The entire device can complete the entire process by using only two sets of telescopic push rods in a synchronized manner. The various functional modules work together to simplify the equipment structure while significantly improving operating efficiency and automation.

[0056] Method of using the tannin extraction residue pressure filter of the present invention:

[0057] The operation of this tannin extraction residue filter press device is carried out in an orderly manner in five stages: equipment pre-inspection and reset, constant pressure feeding and loading, staged pressure filtration, synchronous unloading and filtration, and reset cycle preparation. The specific operation procedures and technical requirements are as follows:

[0058] Step 1: Equipment Pre-inspection and Workstation Reset

[0059] Before formal feeding, complete the equipment status check and station reset: Confirm that the first telescopic push rod is fully extended, the cover plate is raised to the bottom working position of the filter box, and the sealing layer is tightly fitted with the filter box opening without gaps; confirm that the second telescopic push rod is fully retracted, the pressure plate is returned to the initial position on the side of the filter chamber, and there is sufficient space inside the filter chamber; confirm that the moving plate of the cleaning mechanism is in the standby position at the top of the filter chamber, without occupying the filtration space or interfering with the movement of the pressure plate. Check the status of the feed pipeline valves to ensure that the pipeline is unobstructed; check the connection and sealing of the liquid outlet pipe and the liquid storage tank, and straighten the flexible pipe to avoid bending and squeezing to ensure that the drainage path is unobstructed. At the same time, visually check whether the filter cloth on the filter plate surface is flat and intact, and whether there are any obstructions or foreign objects in the gaps between the sliding parts. After completing all pre-inspections, start the equipment control system and enter the standby feeding state.

[0060] Step 2: Constant pressure feeding and filling

[0061] The pretreated tannin extraction residue is pumped into the filter box through the feed pipe using a slurry pump, evenly filling the filter chamber space between the pressure plate and the filter plate. During feeding, the output pressure of the slurry pump is controlled within the range of 0.2~0.3MPa, and a slow injection method is adopted to avoid instantaneous material impact that could cause filter cloth displacement or damage. During feeding, the telescopic push rod can be controlled to make small-stroke reciprocating micro-movements, causing slight disturbance of the material to assist in even distribution and avoid local accumulation that would affect the subsequent filtration effect. When the filter chamber is completely filled with material and the pressure in the feed pipe shows a slight and stable increase, feeding is stopped and the feed pipe valve is closed, completing the material filling and providing a uniform and stable material foundation for subsequent filtration.

[0062] Step 3: Staged pressure filtration and filtrate collection

[0063] Activate the telescopic push rod two to move the slide bar horizontally at low speed. This, along with the sliding block, slowly moves the pressure plate towards the filter plate, graded and pressurized the residue in the filter chamber. This avoids sudden high pressure that could cause the filter cake to crack or the filter cloth to break. The pressing process consists of two stages: the first stage is low-pressure pre-pressing, maintaining the pressing pressure at approximately 0.5 MPa for 3-5 minutes to allow the residue to initially dehydrate and solidify, removing most of the free water. The second stage is high-pressure holding, gradually increasing the pressure to the working pressure of 1.2-1.5 MPa and holding for 8-12 minutes to enhance capillary water removal and further reduce the moisture content of the filter cake. During pressing, the filtrate flows down the surface of the filter plate under gravity into the discharge port on the cover plate, and then through the outlet pipe and flexible pipeline into the storage tank for temporary storage. The filtrate flow rate is monitored in real time. When the filtrate flow rate significantly decreases and the filter cake solidifies, the pressing process is complete.

[0064] Step 4: Simultaneous unloading and filter plate cleaning

[0065] After filtration is completed, the second telescopic pusher is first slowly retracted at a low speed, causing the pressure plate to smoothly return to its initial position, completely separating the pressure plate from the filter cake and preventing the negative pressure generated by rapid plate retraction from causing the filter cake to break. Then, the first telescopic pusher is activated to retract at a uniform speed, causing the cover plate to move vertically downwards. Under its own gravity, the filter cake descends synchronously with the cover plate, gradually detaching from the filter chamber body. Simultaneously, the connecting rods on both sides drive the support and sliding rods downwards, driving the moving plate to slide downwards along the filter chamber. The lower end face assists in pushing the filter cake completely out of the filter box. At the same time, the brush on the side of the moving plate sweeps uniformly along the surface of the filter plate, removing any remaining fine residue from the filter cloth. Once the cover plate has descended to its lowest position, a transfer tool is used to remove the intact filter cake from the cover plate, completing the unloading and filter plate cleaning operation.

[0066] Step 5: Equipment Reset and Cycle Preparation

[0067] After unloading and cleaning, extend the telescopic push rod at a uniform speed, pushing the cover plate upwards and re-sealing it against the bottom of the filter box. Simultaneously, the linkage rod drives the bracket, sliding rod, and moving plate to rise synchronously, returning to the initial standby position at the top of the filter chamber. After confirming that all moving parts are in place and the sealing performance is normal, the next round of feeding and filtration cycle can be started. After each shift, the surface of the cover plate and the brush of the moving plate can be rinsed with clean water to remove residual residue. Regularly check the wear of the seals and the integrity of the filter cloth, and replace worn parts in a timely manner to ensure long-term stable operation of the equipment.

[0068] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A tannin extraction residue filter press, comprising a base (1), a mounting frame (2) fixedly connected to the base (1), a filter press (3) fixedly passing through the mounting frame (2), the filter press (3) comprising a filter box fixedly passing through the mounting frame (2), a filter plate fixedly connected inside the filter box, a pressure plate movable inside the filter box, and a feed pipe connected to the upper half of the filter box, characterized in that: The filter press (3) is equipped with a drive mechanism (4), which is used to drive the filter press (3) to filter the residue. The bottom of the filter press (3) is equipped with a feeding device (5), which includes a capping mechanism (510) and a cleaning mechanism (520). The capping mechanism (510) is connected to a draining mechanism (6), which is used to drain the liquid filtered out of the filter press (3). The sealing mechanism (510) is used to move and close the bottom opening of the filter box; The cleaning mechanism (520) is used to push the filter cake downwards out of the filter box and to clean the residue on the filter plate.

2. The tannin extraction residue pressure filter according to claim 1, characterized in that: The sealing mechanism (510) includes a cover plate (511) that moves to seal the bottom opening of the filter box, and a telescopic push rod (512) for pushing the cover plate (511) to move and seal is fixedly connected at the bottom center of the cover plate (511).

3. The tannin extraction residue pressure filter according to claim 1, characterized in that: The cleaning mechanism (520) includes a connecting rod (521) on both sides of the sealing mechanism (510). The top end of the connecting rod (521) is connected to a bracket (522), and the bottom end of the bracket (522) is connected to a sliding rod (523). The bottom end of the sliding rod (523) is moved into the through hole (524) and is fixedly connected to a moving plate (525) for pushing the filter cake down and cleaning the filter plate.

4. The tannin extraction residue pressure filter according to claim 1, characterized in that: The discharge mechanism (6) includes a discharge port (61) opened on the capping mechanism (510), the bottom end of the discharge port (61) is connected to the discharge pipe (62), the outer end of the discharge pipe (62) is connected to the pipe (63), and the free end of the pipe (63) is connected to the storage tank (64).

5. The tannin extraction residue pressure filter according to claim 1, characterized in that: The drive mechanism (4) includes a bracket (41) mounted on the filter box. A telescopic push rod (42) is mounted on the bracket (41). A slide rod (43) is connected to the extended end of the telescopic push rod (42). The slide rod (43) moves through a sliding seat (44) at the end away from the telescopic push rod (42) and is fixedly connected to a sliding block (45) for driving the pressure plate to move and press the filter.

6. The tannin extraction residue pressure filter according to claim 2, characterized in that: The cover plate (511) is larger than the bottom opening of the filter box. The top surface of the cover plate (511) is provided with a sealing layer. The bottom end of the telescopic push rod (512) is fixedly connected to the base plate (1).

7. A tannin extraction residue pressure filter according to claim 3, characterized in that: Two sets of linkage rods (521) are symmetrically arranged on the side wall of the cover plate (511). The number of sliding rods (523) is equal to the number of filter plates. The through hole (524) is opened on the top of the filter box. The moving plate (525) is wrapped with a sealing layer. The moving plate (525) is provided with a brush on the side wall near the filter plate.

8. A tannin extraction residue pressure filter according to claim 4, characterized in that: The discharge port (61) is located on the cover plate (511) on one side of the filter plate. The number of discharge ports (61) is equal to the number of filter plates. The sum of the height of the discharge port (611) and the height of the pipe (63) is less than the height of the cover plate (511). The pipe (63) is arranged inside the cover plate (511). The length of the pipe (63) is less than the length of the cover plate (511). The pipe (63) is a flexible hose.

9. A tannin extraction residue pressure filter according to claim 5, characterized in that: The bracket (41) has an L-shaped structure. The telescopic push rod (42) is used to drive the slide rod (43) to move back and forth. The sliding seat (44) has a groove on one side. The open end of the sliding seat (44) is connected to the side wall of the filter box. The sliding block (45) is slidably connected to the sliding seat (44). One end of the sliding block (45) is fixedly connected to the side wall of the pressure plate.

10. A method of using the tannin extraction residue pressure filter device according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Equipment Pre-inspection and Station Reset: Before the filter press operation, perform a pre-inspection of the filter press device and reset each component to its station position; control the telescopic push rod one to fully extend, so that the cover plate is sealed and positioned against the bottom of the filter box; control the telescopic push rod two to fully retract, so that the pressure plate returns to its initial position on the side of the filter chamber; at the same time, control the moving plate of the cleaning mechanism to return to the standby position at the top of the filter chamber, without occupying the filter press space or interfering with the movement of the pressure plate; check that the feed pipe is unobstructed and free from blockages; check that the connection between the liquid outlet pipe and the liquid storage tank is sealed and intact; straighten the flexible pipe to avoid bending and squeezing, and ensure that the discharge path is unobstructed; visually inspect that the filter cloth on the surface of the filter plate is flat and intact, and that there is no jamming or foreign matter in the gaps between the sliding parts; after completing all pre-inspections, start the equipment control system to put the equipment into the standby feeding state; S2. Constant Pressure Feeding and Filling: The pretreated tannin extraction residue is pumped into the filter box through the feed pipe using a slurry pump, so that the material is evenly filled into the filter chamber space between the pressure plate and the filter plate. During the feeding process, the output pressure of the slurry pump is controlled at 0.2~0.3MPa, and a low-speed, slow injection method is adopted to avoid material impact causing filter cloth displacement and damage. At the same time, the telescopic push rod 2 is controlled to make small-stroke reciprocating micro-movements, which causes slight disturbance of the material, so as to achieve uniform material distribution and prevent local material accumulation. When the filter chamber is completely filled with material and the pressure in the feed pipe rises slightly and steadily, the feeding is stopped and the feed pipe valve is closed to complete the material filling. S3. Staged Pressure Filtration and Filtrate Collection: After feeding, activate the telescopic push rod two to move the slide bar horizontally at low speed. This, along with the sliding block, drives the pressure plate slowly towards the filter plate, performing staged pressure pressing on the residue within the filter chamber. First, perform low-pressure pre-pressing, maintaining the pressing pressure at a suitable value for 3-5 minutes to allow the residue to initially dehydrate and solidify, removing most of the free water. Then, perform high-pressure holding, gradually increasing the pressure to 1.2-1.5 MPa and holding for 8-12 minutes to remove capillary water from the residue and reduce the moisture content of the filter cake. During the filtration process, the filtrate flows downwards along the filter plate surface under gravity into the cover plate's discharge port, and then through the outlet pipe and flexible pipeline into the storage tank for temporary storage. Monitor the filtrate flow rate in real time; once the filtrate flow rate significantly decreases and the filter cake formation stabilizes, the filtration process is complete. S4. Synchronous Unloading and Filter Plate Cleaning: After the filtration process is completed, control the telescopic push rod two to retract slowly at low speed, driving the pressure plate back to its initial position smoothly, so that the pressure plate and filter cake are completely separated, avoiding the negative pressure adsorption caused by rapid plate retraction that could lead to filter cake breakage; then control the telescopic push rod one to retract at a uniform speed, driving the cover plate to move vertically downwards, and the filter cake relies on its own gravity to descend synchronously with the cover plate and detach from the filter chamber body; during the descent of the cover plate, the linkage rods on both sides drive the support and sliding rod to descend synchronously, driving the moving plate to slide downwards along the filter chamber, and the lower end face of the moving plate assists in pushing the filter cake completely out of the filter box, while the brush on the side of the moving plate sweeps the surface of the filter plate at a uniform speed to remove the fine residual residue attached to the filter cloth surface; after the cover plate is lowered to the lowest position, the complete filter cake on the cover plate is removed by the transfer tool, completing the unloading and filter plate cleaning operation; S5. Equipment Reset and Cycle Preparation: After unloading and cleaning, control the telescopic push rod to extend at a uniform speed, pushing the cover plate upwards to reset, so that the cover plate re-seals and fits against the bottom of the filter box; at the same time, the linkage rod drives the bracket, sliding rod and moving plate to rise synchronously, so that the moving plate returns to the initial standby position at the top of the filter chamber; after confirming that all moving parts of the equipment are fully reset, and that the sealing performance and pipeline status are normal, the next round of feeding and filtration cycle can begin; after each shift of production, rinse the surface of the cover plate and the brush of the moving plate with clean water to remove residual residue; regularly check the wear of the equipment seals and the integrity of the filter cloth, and replace worn parts in a timely manner to ensure stable operation of the equipment.

Images