A start-up sealed counterflow dryer

Abstract

A kind of start sealed counterflow dryer belongs to feed processing equipment technical field, including bunker, material collecting hopper and support, the upper portion of the bunker is equipped with feed inlet and air extraction port, inside is equipped with bin position sensor, side wall is equipped with window and control panel, bottom is material leakage screen;The support is equipped with the horizontal frame of bearing bin and the horizontal frame of bearing screen;Bunker is installed on the horizontal frame of bearing bin, material leakage screen is installed on the horizontal frame of bearing screen, the lower surface of the material leakage screen is closely installed with sealing mechanism, the sealing mechanism is formed by the left and right two sealing plates with same structure, the material collecting hopper includes split horn funnel, middle layer four pyramid horn funnel and four prism discharge port;The opening edge of upper split horn funnel is fixed on the bracket leg below the horizontal frame of bearing screen;Its beneficial effect is that the sealing plate is closely attached to the material leakage screen to seal the bunker bottom, prevents the air below the bunker bottom from entering, so that the air extractor dries all the feed particles in the bunker, greatly improves the production efficiency.

Description

A start-up sealed counter-current dryer Technical Field

[0001] This invention belongs to the technical field of feed processing equipment, specifically a start-up sealed counter-current dryer. Background Technology

[0002] In feed processing, to kill bacteria and facilitate pelleting, the feed is steam-heated and conditioned before pelleting. The pelleting process also generates a significant amount of heat, resulting in pellets with a certain level of moisture and temperature. Before packaging and storage, the pelleted feed must be cooled and dried. Current feed drying methods generally employ counter-current dryers, which utilize air flowing in the opposite direction to the pellet flow to remove moisture from the pellets, thus drying them.

[0003] Existing counter-current dryers have a feed inlet at the top of the drying silo, an exhaust vent on the upper side connected to an external exhaust fan, and a material screening screen, a collection hopper, and a discharge outlet at the bottom. During operation, exhaust cooling and drying begins as soon as the matured pellets enter the cooling and drying silo. After 15-20 minutes, when the matured pellets have accumulated to two-thirds of the silo's volume, a sensor automatically activates the material screening screen to allow the material to proceed to the next process. However, due to defects in the currently used dryers, the first 2-3 tons of pellets at the bottom of the drying silo have excessive moisture content. After steam maturation, the moisture content of the powder entering the pellet mill is generally 15%, and the acceptable moisture content after cooling and drying is below 13%. In actual production, however, the moisture content of only the first 2-3 tons of pelleted feed is consistently around 14%. The current industry practice is to rework the first 2-3 tons of each type of pelleted feed, severely reducing production efficiency. Summary of the Invention

[0004] The technical problem this invention aims to solve is to address the aforementioned defects. Observation and research have revealed that the main reason for the excessive moisture content in the first 2-3 tons of pelleted feed per batch is the poor sealing of the bottom sieve of the drying chamber, allowing outside air to escape. Therefore, this invention provides a start-up sealed counter-current dryer that improves drying efficiency. Observation and research have also found that the poor drying effect of the first 2-3 tons of feed is due to the fact that the sieve can only seal the formed pellets, not the air at the bottom of the sieve. During the first 20 minutes of dryer startup, when the formed pellets initially accumulate at the bottom of the hopper and the feed layer is small, most of the air drawn by the exhaust fan comes from outside air entering below the sieve, failing to effectively remove moisture from the formed pellets. Therefore, this solution provides a hopper that blocks air from the bottom of the dryer hopper below the sieve, preventing air from entering from the bottom of the dryer hopper and allowing the exhaust fan to only extract the moisture-containing air from the formed pellets, thus improving the drying effect.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is a start-up sealed counter-current dryer, including a hopper, a collection hopper, and a support. The upper part of the hopper is a frustum-shaped cone with a flat top wall and inclined side walls, which can be a truncated cone or a square frustum-shaped cone. The flat top wall is provided with a feed inlet, which is equipped with a first solenoid valve. The inclined side walls are provided with an exhaust port, which is equipped with a second solenoid valve. The exhaust port is connected to a high-pressure blower through an air duct. The lower part of the hopper is a column with vertical side walls, which can be cylindrical or square columnar. A hopper level sensor is installed inside the hopper, and a viewing device is installed on the vertical side walls. The hopper includes a window and control panel. The bottom of the hopper is a material-leaking screen connected to a servo motor. The control panel is electrically connected to a high-pressure blower, a servo motor, a first solenoid valve, a second solenoid valve, a hopper level sensor, and a power supply. The support frame is a square frame with a double-layered support crossbeam. It includes four legs and at least eight equal-length crossbeams. The four equal-length crossbeams form a square and are fixedly installed on the top of the four legs to form the hopper support crossbeam, supporting the upper and lower parts of the hopper. The other four equal-length crossbeams form a square and are fixedly installed on the upper part of the four legs to form the screen support crossbeam, supporting the material-leaking screen. The hopper is fixedly installed above the hopper support crossbeam. The material leakage screen is installed on the screen support frame and close to the lower part of the silo, making the material leakage screen the bottom of the silo. The material leakage screen consists of two grid plates. Each grid plate is composed of several identical square columnar grid bars fixedly installed at equal intervals between two upper and lower base bars. The gap between two adjacent grid bars is less than the thickness of the grid bar, generally made to be equal to 30%-95% of the thickness of the grid bar, preferably 75%. The two grid plates are overlapped and installed, with the upper grid plate fixedly installed at the bottom of the silo. Rollers are installed on both sides of the lower grid plate and are close to the upper grid plate. The rollers are mounted on the crossbeam of the screen support frame and connected to a servo motor. When feed pellets need to be released from the hopper, the servo motor moves the lower grid plate to align the gap on the lower grid plate with the gap on the upper grid plate, allowing the feed pellets to fall. When the feed pellets need to stop falling, the servo motor moves the lower grid plate to misalign the gap on the lower grid plate with the gap on the upper grid plate, intercepting the feed pellets. The collection hopper is installed below the screen support frame, with its upper edge fixedly mounted on the frame legs and located below the feed sieve, for receiving and collecting the formed feed pellets released by the feed sieve.The feature is that a sealing mechanism is tightly installed on the lower surface of the material-discharging screen. The sealing mechanism is composed of two sealing plates with the same structure, one on the left and one on the right. Each sealing plate includes a bottom plate and a top plate. The length of the top plate is equal to the length of the material-discharging screen, the width of the top plate is equal to half the width of the material-discharging screen, and the thickness of the top plate is equal to the thickness of the crossbeam. The two top plates, when combined, can cover and seal the entire material-discharging screen to block air and prevent air from entering the hopper from below the screen when the fan is drawing air out. This allows the fan to only draw out the humid air from the hopper and the feed pellets to dry the feed pellets. The length of the bottom plate is equal to the distance between the outer sides of two corresponding crossbeams on the screen support frame, and the width of the bottom plate is equal to the width of the top plate. A shaft is directly connected to the rear side of the bottom plate. Bearing seats are fixedly installed at four positions near the legs on the lower side of the two corresponding crossbeams on the screen support frame. Each bearing seat contains a bearing. Both ends of the shaft are installed in bearings. The panel is fixedly attached to the middle of the base plate, and the panel is offset outwards in the width direction, so that the panel extends beyond the base plate in the width direction. At the same time, the base plate extends beyond the panel in the length direction on both sides. A hanging rope is fixedly connected to the front side of the base plate extending beyond the panel in the length direction. Two hooks are fixedly installed at the middle of the outer sides of two corresponding crossbeams on the screen support frame. The positions of the hanging ropes and hooks can be interchanged. When the hanging ropes on the two sealing plates are hung on the hooks, the base plate extending beyond the panel will press against the lower surface of the two corresponding crossbeams on the screen support frame, and the upper surface of the panel will press against the lower grid plate, thus sealing the surface under the screen and preventing air from entering. When it is necessary to release feed pellets, the hanging ropes are lowered from the hooks, and the front side of the sealing plate will fall around the shaft. Then, the screen can be opened to release the feed pellets.

[0006] The hopper comprises a three-layer structure: an upper split-flank hopper, a middle quadrangular pyramid flank hopper, and a quadrangular prism discharge port, all directly connected. The split-flank hopper has four sides: its front and rear sides are vertically downward isosceles trapezoidal sides, and its left and right sides are inclined inward and downward rectangular sides. The length of the rectangular sides is greater than or equal to the length of the sealing plate, and the width of the rectangular sides is greater than or equal to the width of the sealing plate. This allows the rectangular sides to catch the sealing plate when it is lowered by the suspension rope. The four sides of the quadrangular pyramid flank hopper are all isosceles trapezoidal. The opening edge of the upper split-flank hopper is fixed to the legs below the screen support frame.

[0007] The fixing method is welding or screwing.

[0008] In use, first, place the two grid panels in a staggered position to seal the feed sieve, forming the bottom of the silo. Then, press the sealing plate tightly, ensuring the front panel is flush against the lower grid panel and the bottom plate is flush against the screen support frame. Next, hang the hanging rope on the bottom plate onto the hooks on the screen support frame, thus sealing the entire bottom of the silo. Then, open the first and second solenoid valves to feed the matured feed pellets into the silo through the inlet. Start the exhaust vent to cool and dry the feed pellets inside the silo. This prevents air from entering the silo from below during exhaust, allowing the exhaust fan to completely cool and dry the feed pellets. After 15-20 minutes of cooling and drying, when the formed pellets have accumulated to two-thirds of the capacity in the cooling and drying hopper, the lifting rope is removed from the hook, the sealing plate is lowered, and the panel and bottom plate are placed on the split-flange hopper. Then, the hopper level sensor automatically activates the leakage screen to sift the material, allowing the dried feed pellets to fall into the collection hopper for the next process. Inspection shows that the moisture content of the cooled and dried feed pellets is all below 13%, meeting all qualification requirements. The first batch of 2-3 tons of feed products no longer requires rework, greatly improving production efficiency.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] (1) A sealing mechanism consisting of two sealing plates on the left and right is set up, which can seal the bottom of the silo by tightly sticking the sealing plate to the material screen, thereby preventing air from entering from the bottom of the silo, so that the exhaust fan can dry all the feed particles in the silo. In this way, the first 2-3 tons of feed after the dryer is started do not need to be reworked, which greatly improves production efficiency.

[0011] (2) Set the sealing plate as a staggered panel and bottom plate so that the panel is directly attached to and completely seals the leakage screen, and the bottom plate is directly hung on the screen support frame and supports the panel.

[0012] (3) The upper part of the hopper is set as a split horn hopper, which can allow the split inclined horn hopper wall to support the falling left and right sealing plates. Attached Figure Description

[0013] Figure 1 is a side view of the structure of the sealing plate sealing the leaking screen in this invention.

[0014] Figure 2 is a side view of the structure when the sealing plate is opened and detached from the leakage screen in this invention.

[0015] Figure 3 is a schematic diagram of the sealing plate in this invention.

[0016] Figure 4 is a schematic diagram of the structure of the material collection hopper in this invention.

[0017] In the diagram: 1. Hopper, 2. Collecting hopper, 3. Support frame, 4. Flat top wall, 5. Inclined side wall, 6. Feed inlet, 7. First solenoid valve, 8. Exhaust vent, 9. Second solenoid valve, 10. Viewing window, 11. Control panel, 12. Leaking screen, 13. Servo motor, 14. Frame leg, 15. Crossbeam, 16. Hopper support frame, 17. Screen support frame, 18. Fence plate, 19. Sealing plate, 20. Base plate, 21. Panel, 22. Shaft, 23. Bearing seat, 24. Lifting rope, 25. Hook, 26. Split horn hopper, 27. Four-sided pyramid horn hopper, 28. Four-sided prism discharge port. Detailed Implementation

[0018] The present invention will be further described below with reference to the embodiments. The following embodiments are intended to illustrate the present invention and not to further limit the present invention, and should not be used to limit the scope of protection of the present invention.

[0019] As shown in Figures 1 and 2, this invention provides a start-up sealed counter-current dryer, which includes a hopper 1, a collection hopper 2, and a support 3. The upper part of the hopper 1 is a frustum-shaped hopper top including a flat top wall 4 and inclined side walls 5, which can be a frustum-shaped cone or a square frustum-shaped cone; in this case, it is a square frustum-shaped hopper top. The flat top wall 4 is provided with a feed inlet 6, and the feed inlet 6 is provided with a first solenoid valve 7. The inclined side walls 5 are provided with an exhaust port 8, and the exhaust port 8 is provided with a second solenoid valve 9. The exhaust port 8 is connected to a high-pressure blower through an air duct. The lower part of the hopper 1 is a columnar vertical side wall, which can be cylindrical or square columnar; in this case, it is a square prism. The hopper 1 is provided with a hopper level sensor, and the vertical side walls are provided with a viewing window 10 and a... The control panel 11 has a material leakage screen 12 at the bottom of the hopper 1, which is connected to a servo motor 13. The control panel 11 is electrically connected to a high-pressure blower, the servo motor 13, a first solenoid valve 7, a second solenoid valve 9, a hopper level sensor, and a power supply. The support 3 is a square support with a double-layer support frame, including four legs 14 and at least eight equal-length beams 15. The four equal-length beams form a square and are fixedly installed on the top of the four legs 14 to form a hopper support frame 16, which supports the upper and lower parts of the hopper 1. The other four equal-length beams 15 form a square and are fixedly installed on the upper part of the four legs to form a screen support frame 17, which supports the material leakage screen 12. The hopper 1 is fixedly installed above the hopper support frame 16. The material leakage screen 12 is installed on the screen support frame 17 and closely attached to the lower part of the silo 1, making the material leakage screen 12 the bottom of the silo 1. The material leakage screen 12 is composed of two fence plates 18. Each fence plate 18 is composed of several identical square columnar fence bars fixedly installed at equal intervals between two bottom rods. The gap between two adjacent fence bars is less than the thickness of the fence bar. Generally, the gap between two adjacent fence bars is made to be equal to 30%-95% of the thickness of the fence bar. In this embodiment, the gap between two adjacent fence bars is made to be equal to 75% of the thickness of the fence bar. The two fence plates 18 are overlapped and installed. The upper fence plate is fixedly installed at the bottom of the silo 1, and the lower fence plate is installed on both sides. The rollers are mounted on the crossbeam 15 of the screen support frame 17 and are connected to the servo motor 13. When feed pellets need to be released from the hopper 1, the servo motor 13 moves the lower screen to align the gap on the lower screen with the gap on the upper screen, allowing the feed pellets to fall. When the feed pellets need to stop falling, the servo motor 13 moves the lower screen to misalign the gap on the lower screen with the gap on the upper screen, intercepting the feed pellets. The collecting hopper 2 is installed below the screen support frame 17, with its upper edge fixedly mounted on the frame leg 14 and located below the feed sieve 12. It is used to receive and collect the formed feed pellets released from the feed sieve 12.The key feature here is the sealing mechanism tightly installed on the lower surface of the material leakage screen 12. This sealing mechanism consists of two sealing plates 19 with identical structures, one on the left and one on the right. Each sealing plate 19 includes a base plate 20 and a panel 21. The length of the panel 21 is equal to the length of the material leakage screen 12, the width of the panel 21 is equal to half the width of the material leakage screen 12, and the thickness of the panel 21 is equal to the thickness of the crossbeam 15. In other words, the two panels 21, when combined, can cover and seal the entire material leakage screen 12, preventing air from entering from below the screen when the fan is drawing air in. Inside the feed hopper 1, the blower only extracts the moist air from inside the feed hopper 1 and the feed pellets to dry the feed pellets; the length of the bottom plate 20 is equal to the distance between the outer sides of the two corresponding crossbeams 15 on the front and rear of the screen support frame 17, and the width of the bottom plate 20 is equal to the width of the panel 21. A shaft 22 is directly connected to the rear side of the bottom plate 20. Bearing seats 23 are fixedly installed at four positions near the frame legs 14 on the lower side of the two corresponding crossbeams 15 on the front and rear of the screen support frame 17. Bearings are installed inside the bearing seats 23, and the two ends of the shaft 22 are installed inside the bearings. The panel 21 is fixedly attached to the middle of the base plate 20, and the panel 21 is offset outward in the width direction, so that the panel 21 extends beyond the base plate 20 in the width direction. At the same time, the base plate 20 extends beyond the panel 21 on both sides in the length direction. A hanging rope 24 is fixedly connected to the front side of the base plate 20 extending beyond the panel 21. Meanwhile, two hooks 25 are fixedly installed on the middle of the outer sides of the two corresponding crossbeams 15 on the screen support frame 17. The positions of the hanging rope 24 and the hooks 25 can be interchanged, or the hanging rope 24 can also be set as a hook. 25. When the ropes 24 on the two sealing plates 19 are suspended from the hooks 25, the bottom plate 20 extending beyond the panel 21 will adhere to the lower surface of the two corresponding crossbeams 15 on the screen support frame 17. Simultaneously, the upper surface of the panel 21 will adhere to the lower grid plate, thus sealing the lower surface of the feed sieve 12 and preventing air from entering the hopper 1 from the lower surface of the feed sieve 12. When it is necessary to release feed pellets, the ropes 24 are lowered from the hooks 25, and the front of the sealing plate 19 will fall around the shaft 22. Then, the feed sieve 12 can be opened to release the feed pellets.

[0020] The collecting hopper 2 comprises a three-layer structure: an upper split-flank hopper 26, a middle quadrangular pyramid hopper 27, and a quadrangular prism discharge port 28, all directly connected. The split-flank hopper 26 has four side hoppers. Its front and rear sides are vertically downward isosceles trapezoidal sides, and its left and right sides are inclined inward and downward rectangular sides. The length of the rectangular sides is greater than or equal to the length of the sealing plate 19, and the width of the rectangular sides is greater than or equal to the width of the sealing plate 19. This allows the rectangular sides to catch the sealing plate 19 when the hanging rope 24 is removed and the sealing plate 19 falls. The four sides of the quadrangular pyramid hopper 27 are all isosceles trapezoidal. The opening edge of the upper split-flank hopper 26 is fixed to the support legs below the screen support frame 17.

[0021] When in use, first place the two fence panels 18 in a staggered position to seal the material screen 12 and form the bottom of the hopper 1;

[0022] Then, press the sealing plate 19 tightly, making the panel 21 press against the lower grid plate, and press the two sides of the bottom plate 20 against the screen support frame 17. Then, hang the hanging rope 24 on the bottom plate 20 on the hook 25 on the screen support frame 17, thus sealing the bottom of the entire silo 1. Then, open the first solenoid valve 7 and the second solenoid valve 9, and feed the cooked feed pellets into the silo 1 through the feed inlet 6. Start the exhaust fan through the exhaust port 8 to cool and dry the feed pellets in the silo 1. In this way, air below the bottom of the silo 1 can no longer enter the silo 1 during exhaust, and the exhaust fan can completely cool and dry the feed pellets, preventing them from drying from the outside. After 15-20 minutes of air intake, when the formed pellets have accumulated to two-thirds of the capacity in the cooling and drying silo 1, the lifting rope 24 is removed from the hook 25, and the sealing plate 19 is lowered, so that the panel 21 and the bottom plate 20 rest on the rectangular side of the split-flange hopper 26. Then, the silo position sensor automatically opens the leakage screen 12 to screen the material, allowing the dried feed pellets to fall into the collection hopper 2 for the next process. After inspection, the moisture content of the feed pellets after cooling and drying is all below 13%, meeting all the qualification requirements. The first batch of 2-3 tons of feed products no longer needs to be reworked, greatly improving production efficiency.

Claims

1. A start-up sealed counter-current dryer, comprising a hopper, a collection hopper, and a support frame; the upper part of the hopper is a frustum-shaped cone including a flat top wall and inclined side walls, the flat top wall having a feed inlet and the inclined side walls having an exhaust vent; the lower part of the hopper is a columnar column with vertical side walls, a hopper level sensor is installed inside the hopper, a viewing window and a control panel are provided on the vertical side walls, the bottom of the hopper is a material leakage screen connected to a servo motor, and the control panel is electrically connected to a high-pressure fan, a servo motor, the hopper level sensor, and a power supply; the support frame is a square support frame with double-layer support crossbeams, comprising four legs and at least eight equal-length crossbeams, wherein the four equal-length crossbeams form a square and are fixedly installed on the top of the four legs to form the hopper support crossbeams, and the other four equal-length crossbeams form a square and... A screen support frame is fixedly installed on the upper part of four support legs; the hopper is fixedly installed above the hopper support frame, and the leakage screen is installed on the screen support frame and close to the lower part of the hopper; the leakage screen is composed of two grid plates, each grid plate consisting of several identical square columnar grid bars fixedly installed at equal intervals between two bottom bars, wherein the gap between two adjacent grid bars is less than the thickness of the grid bars; the two grid plates are overlapped and installed, with the upper grid plate fixedly installed at the bottom of the hopper, and rollers installed on both sides of the lower grid plate and close to the upper grid plate, and the rollers are movably installed on the crossbeam of the screen support frame and connected to a servo motor; the collecting hopper is installed below the screen support frame, and its upper edge is fixedly installed on the support legs and located below the leakage screen; its characteristic is that... A sealing mechanism is tightly installed on the lower surface of the material-discharging screen. This sealing mechanism consists of two identical sealing plates, one on the left and one on the right. Each sealing plate includes a base plate and a panel. The length of the panel is equal to the length of the material-discharging screen, the width of the panel is half the width of the material-discharging screen, and the thickness of the panel is equal to the thickness of the crossbeam. The length of the base plate is equal to the distance between the outer sides of two corresponding crossbeams on the screen-supporting frame, and the width of the base plate is equal to the width of the panel. A shaft is directly connected to the rear side of the base plate. Bearing seats are fixedly installed at four positions near the legs on the lower side of the two corresponding crossbeams on the screen-supporting frame. Each bearing seat contains a bearing, and both ends of the shaft are installed within the bearings. The panel is fixedly attached to the middle of the base plate, and the panel is offset outwards in the width direction, so that the panel extends beyond the base plate in the width direction. In addition, the base plate extends beyond the panel on both sides along its length, and a hanging rope is fixedly connected to the front side of the base plate extending beyond the panel on both sides along its length. At the same time, two hooks are fixedly installed on the outer middle of the two corresponding crossbeams on the screen support frame. The hopper includes a three-layer structure, namely a directly connected upper split horn hopper, a middle quadrangular pyramid horn hopper, and a quadrangular prism discharge port. The split horn hopper is a four-sided hopper. Its front and rear sides are vertically downward isosceles trapezoidal sides, and its left and right sides are inclined inward and downward rectangular sides. The length of the rectangular side is greater than or equal to the length of the sealing plate, and the width of the rectangular side is greater than or equal to the width of the sealing plate. The four sides of the quadrangular pyramid horn hopper are all isosceles trapezoidal. The opening edge of the upper split horn hopper is fixed to the frame leg below the screen support frame.

2. The start-up sealed counter-current dryer according to claim 1, characterized in that... The upper part of the silo is a square frustum-shaped structure including a flat top wall and inclined side walls, and the lower part of the silo is a square column-shaped structure with vertical side walls.

3. The start-up sealed counter-current dryer according to claim 2, characterized in that... The positions of the suspension rope and the hook can be interchanged.

4. The start-up sealed counter-current dryer according to claim 3, characterized in that... The feed inlet is equipped with a first solenoid valve, the exhaust port is equipped with a second solenoid valve, and the control panel is electrically connected to the first solenoid valve and the second solenoid valve.

5. The start-up sealed counter-current dryer according to claim 4, characterized in that... The gap between two adjacent fence bars in the fence panel is equal to 30%-95% of the thickness of the fence bar.

6. The start-up sealed counter-current dryer according to claim 5, characterized in that... The gap between two adjacent fence bars in the fence panel is equal to 75% of the thickness of the fence bar.

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