Rotary drying device for potato starch

Abstract

This utility model relates to the technical field of potato starch processing equipment, specifically a potato starch drying device based on rotary heat transfer oil heating and pressure regulation, suitable for efficient dehydration treatment in large-scale potato starch production; a rotary potato starch drying device includes a frame; a cylinder horizontally placed on the upper part of the frame, with both ends connected to the frame via bearing seats to achieve rotation, the cylinder having a double-layer structure including an inner liner and an outer shell, the inner liner being used to hold potato starch, and a cavity forming between the outer shell and the inner liner; a heating assembly including: an oil inlet pipe and an oil return pipe communicating with the cavity; a heat transfer oil circulation pump and a heater connecting the oil inlet pipe and the oil return pipe; a secondary cavity located outside the cavity and communicating with the cavity at both ends, one end of the oil return pipe extending into the secondary cavity; a breathing assembly including: a vent pipe extending into the inner liner; a dehumidifier connected to the vent pipe for regulating the humidity and pressure of the gas inside the cylinder; and a drive system including a motor and a reducer, driving the cylinder to rotate through a transmission mechanism.

Description

Technical Field

[0001] This utility model relates to the technical field of potato starch processing equipment, specifically a potato starch drying device based on rotary heat transfer oil heating and pressure regulation, which is suitable for efficient dehydration treatment in large-scale potato starch production. Background Technology

[0002] Potato starch drying is a crucial step in the processing. Existing technologies mainly employ hot air circulating dryers or static heat transfer oil drying equipment, which have the following drawbacks: 1. Poor drying uniformity: In static drying devices, potato starch accumulates at the bottom, and the heat transfer oil only heats the inner liner in one direction, resulting in uneven heating of the potato starch layer (overheating at the bottom and underheating at the top). The standard deviation of moisture content is as high as 1.8%, requiring frequent turning and extending the drying time by more than 40%.

[0003] 2. Low thermal energy utilization: Hot air drying relies on high-temperature gas to blow directly onto the potato starch layer, and the exhaust temperature often reaches 80-100℃, with a large amount of waste heat not being recovered (heat loss >25%); while traditional heat transfer oil equipment lacks a closed-loop flow channel design, resulting in high oil circuit circulation resistance and significant reduction in heat exchange efficiency.

[0004] 3. Humidity control failure: When the cylinder expands due to heat or contracts due to cooling, the existing equipment lacks a pressure balance mechanism, which causes external moisture to be drawn back into the cylinder (especially during the cooling stage), causing the dried potato starch to become damp and clump together; although some equipment has added exhaust valves, they cannot absorb moisture at the same time, affecting the stability of the moisture content of the final product. Utility Model Content

[0005] To overcome the problems of uneven heating of potato starch caused by static drying, low heat utilization rate of traditional hot air or heat transfer oil equipment, and moisture backflow caused by pressure fluctuations inside the cylinder in the existing technology, this utility model provides a potato starch rotary drying device. By combining a rotating cylinder with closed-loop heat transfer oil circulation heating and breathing pressure regulating components, it can achieve stable drying of potato starch with dynamic thin-layer uniform heating, efficient heat utilization, and zero moisture intrusion.

[0006] The technical solution adopted by this utility model to solve its technical problem is as follows: a potato starch rotary drying device, including a frame; a cylinder horizontally placed on the upper part of the frame, the two ends of which are connected to the frame through bearing seats to achieve rotation, the cylinder having a double-layer structure, including an inner liner and an outer shell, the inner liner being used to hold potato starch, and a cavity being formed between the outer shell and the inner liner; a heating assembly, including: an oil inlet pipe and an oil return pipe communicating with the cavity; a heat transfer oil circulation pump and a heater connecting the oil inlet pipe and the oil return pipe; a secondary cavity disposed outside the cavity and communicating with the cavity at both ends, one end of the oil return pipe extending into the secondary cavity; a breathing assembly, including: a vent pipe extending into the inner liner; a dehumidifier connected to the vent pipe for regulating the humidity and pressure of the gas inside the cylinder; and a drive system, including a motor and a reducer, driving the cylinder to rotate through a transmission mechanism.

[0007] In the aforementioned rotary drying device for potato starch, multiple spiral or annular baffles are arranged at intervals within the cavity, and the baffles do not completely block the cavity.

[0008] The aforementioned rotary drying device for potato starch further includes a first bushing and a first rotary joint in the heating assembly; the first bushing is fixed to the frame and connected to the outer shell, and a first flow channel communicating with the cavity is opened inside it; the first rotary joint is installed at the end of the first bushing and connected to the oil inlet pipe and the oil return pipe.

[0009] In the aforementioned rotary drying device for potato starch, the inlet end of the air guide pipe is provided with an air guide cover with a mesh, the mesh aperture being smaller than the potato starch particle size.

[0010] In the aforementioned rotary drying device for potato starch, the desiccant is a silica gel jar filled with color-changing silica gel particles.

[0011] In the aforementioned rotary drying device for potato starch, the reducer is a worm gear reducer.

[0012] The aforementioned rotary potato starch drying device includes a transmission mechanism comprising: a first pulley mounted on the output shaft of a motor; a second pulley mounted on the input shaft of a reducer; a first belt connecting the first pulley and the second pulley; a third pulley mounted on the output shaft of the reducer; a fourth pulley fixed to the outer circumference of a second bushing; and a second belt connecting the third pulley and the fourth pulley.

[0013] In the aforementioned rotary drying device for potato starch, the motor can rotate in both directions, and the rotation direction of the cylinder can be switched periodically by a controller.

[0014] The aforementioned rotary potato starch drying device has an inlet with a flip-top cover at one end of the cylinder and an outlet controlled by a butterfly valve at the other end.

[0015] The aforementioned rotary drying device for potato starch has an inner liner made of stainless steel and an outer shell wrapped with insulating cotton.

[0016] The beneficial effects of this utility model are: 1. Improved drying uniformity: The rotating cylinder design combined with bidirectional drive causes the potato starch to tumble periodically under the action of centrifugal force and gravity, forming a dynamic thin layer in contact with the heat source, eliminating local overheating or underheating.

[0017] 2. High efficiency in heat energy utilization: The closed-loop heat transfer oil circulation system, combined with the secondary cavity flow guide design, achieves uniform heat transfer, reduces oil circuit resistance and heat loss, and significantly improves energy utilization.

[0018] 3. Precise humidity control: The breathing component automatically balances the pressure inside the cylinder, and the dehumidifier simultaneously absorbs moisture from the exhaust gas and dries the intake air, effectively preventing the potato starch from becoming damp and clumping.

[0019] 4. Stable overall operation: The self-locking function of the reducer and the rotary sealing structure ensure long-term reliable operation of the equipment and meet the needs of large-scale continuous production. Attached Figure Description

[0020] The present invention will be further described below with reference to the embodiments and examples.

[0021] Figure 1 This is a schematic diagram of the external structure of an embodiment.

[0022] Figure 2 This is a cross-sectional structural diagram of an embodiment.

[0023] In the diagram: 1. Top cover; 2. Cylinder; 3. Frame; 4. Reducer; 5. Motor; 6. First rotary joint; 7. Oil inlet pipe; 8. Oil return pipe; 9. First bushing; 10. Secondary chamber; 11. Cavity; 12. Butterfly valve; 13. Air guide hood; 14. Air guide pipe; 15. Second bushing; 16. Second rotary joint; 17. Pressure gauge; 18. Four-way connector; 19. Thermometer; 20. Dehumidifier. Detailed Implementation

[0024] This embodiment provides a rotary drying device for potato starch, such as... Figure 1-2 As shown, the device achieves efficient drying of potato starch by rotating the cylinder 2 in combination with heat transfer oil circulation heating and pressure regulation by a breathing component. The device is based on a frame 3, with the cylinder 2 placed horizontally on top. The two ends of the cylinder 2 are connected to the frame 3 through bearing seats to achieve stable rotation. The cylinder 2 adopts a double-layer structure, including an inner liner and an outer shell. The inner liner is used to hold the potato starch to be dried, and a cavity 11 is formed between the outer shell and the inner liner. Multiple baffles are arranged at intervals in the cavity 11. The baffles are spiral or annularly distributed and only serve to support and guide the flow without completely blocking the cavity 11, ensuring uniform flow of heat transfer oil. The outer shell is wrapped with heat insulation cotton to reduce heat loss. One end of the cylinder 2 is provided with a feed port, which is connected to a flip-up cover 1 by a hinge. The edge of the cover 1 is locked and fixed to the feed port by bolts to ensure sealing. The other end is provided with a discharge port, and a butterfly valve 12 is installed at the discharge port. The butterfly valve 12 is driven by a motor 5 to rotate and open and close, realizing discharge control. Heating components and breathing components are respectively provided on both sides of the cylinder 2.

[0025] The heating assembly is located at one end of the upper part of the frame 3, including an oil pipe, a first rotary joint 6, a first bushing 9, and a circulation system. The first bushing 9 is horizontally fixed to the frame 3 via a bearing seat and bolted to one side of the outer casing. An axial first flow channel is formed inside the bushing 9, which communicates with the cavity 11. The first rotary joint 6 is installed at the end of the first bushing 9, which has a rotary sealing function to prevent heat transfer oil leakage. One end of the first rotary joint 6 is threaded to the oil pipe, which is divided into an oil inlet pipe 7 and an oil return pipe 8. The oil inlet pipe 7 extends axially along the first flow channel to the cavity 11. Inside, a secondary cavity 10 is added to the outer side of the cavity 11 near the first bushing 9. The two ends of the secondary cavity 10 are connected to the cavity 11. One end of the return oil pipe 8 extends into the secondary cavity 10. The inlet oil pipe 7 and the return oil pipe 8 are connected to a heat transfer oil circulation pump and a heater. The circulation pump provides power to make the heat transfer oil flow, and the heater continuously replenishes heat. During operation, the high-temperature heat transfer oil flows into the cavity 11 through the inlet oil pipe 7 and transfers heat to the potato starch through the inner wall of the liner. After heat exchange, the heat transfer oil flows into the secondary cavity 10 through the cavity 11 and then returns to the heater through the return oil pipe 8 for reheating, forming a closed loop circulation.

[0026] The breathing assembly is located at the other end of the upper part of the frame 3 and is used to regulate the gas pressure inside the cylinder 2. It includes a second bushing 15, an air guide hood 13, an air guide pipe 14, a second rotary joint 16, a pressure gauge 17, a thermometer 19, a four-way connector 18, and a dehumidifier 20. The second bushing 15 is horizontally fixed to the frame 3 through a bearing seat and bolted to the other side of the outer shell. An air guide pipe 14 is installed inside the bushing. One end of the air guide pipe 14 extends into the inner liner and is fitted with an air guide hood 13. The air guide hood 13 is cylindrical and has uniformly opened mesh holes with a diameter smaller than that of potato starch particles on its surface to prevent potato starch from entering the air guide pipe 14. The other end of the air guide pipe 14 is connected to the second rotary joint 16. The second rotary joint 16 connects to the four-way joint 18. A pressure gauge 17 and a thermometer 19 are installed sequentially on the upper part of the four-way joint 18 to monitor the internal pressure and temperature of the inner liner in real time. The other end of the four-way joint 18 is connected to a color-changing silica gel desiccant 20 (technology transferred to transformer silica gel tanks). The desiccant is filled with silica gel particles. When the inner liner expands due to heat, the internal air pressure increases, and the gas is discharged through the air guide hood 13 and the air guide pipe 14. The desiccant 20 absorbs the moisture in the gas. When the oil temperature decreases and the inner liner contracts, the outside air is dried by the desiccant 20 and then drawn into the inner liner to prevent moisture from entering and affecting the drying effect of the potato starch.

[0027] To prevent potato starch from accumulating at the bottom of the drum 2, which would lead to uneven heating and a decrease in drying rate, this embodiment adds a drive system consisting of a motor 5 and a reducer 4 to the upper part of the frame 3. Stable rotation of the drum 2 is achieved via belt drive. The motor 5 is a three-phase asynchronous motor, fixed to one side of the upper part of the frame 3. A first pulley is installed at the end of its output shaft, and the first pulley is circumferentially fixed to the motor 5 shaft via a flat key to prevent slippage. The reducer 4 is a worm gear reducer with a self-locking function to prevent the drum 2 from drying due to inertia or load fluctuations. Reversal occurs. A second pulley is installed at the end of the input shaft of the reducer 4. The output shaft is fixed to the second bushing 15 via a key connection. A first belt (such as a V-belt) is fitted between the first pulley and the second pulley. The belt is tensioned by adjusting the position of the motor 5 or the reducer 4 to ensure transmission efficiency. A second belt is fitted between the third pulley at the output shaft end of the reducer 4 and the fourth pulley on the outer circumference of the second bushing 15. The second bushing 15 serves as a fixed fulcrum for the rotation of the cylinder 2. Its outer circumferential pulley is circumferentially fixed by a flat key to ensure that power is transmitted to the cylinder 2.

[0028] After the motor 5 starts, the power is transmitted to the input shaft of the reducer 4 via the first pulley and the first belt. After the torque is reduced by the worm gear, the second shaft sleeve 15 is driven to rotate by the third pulley and the second belt at the output shaft end. Since the second shaft sleeve 15 is rigidly connected to the outer shell by bolts, the cylinder 2 rotates synchronously. The cylinder 2 can be rotated bidirectionally by the forward and reverse rotation of the motor 5 to avoid unidirectional accumulation of potato starch. For example, the rotation direction is switched every 30 minutes of drying, so that the potato starch is alternately tumbled under the action of centrifugal force and gravity, and fully contactes the inner hot wall. The speed of the motor 5 is adjusted by the frequency converter to control the rotation speed of the cylinder 2 within the range of 0.5-5 rpm to meet the drying needs of potato starch with different particle sizes. Lower rotation speed reduces potato starch breakage, while higher rotation speed enhances heat transfer efficiency. When the cylinder 2 rotates, the potato starch adheres to the inner wall of the inner liner due to centrifugal force, and slowly slides down the wall due to gravity, forming a "rolling curtain" effect. This ensures that all potato starch particles periodically contact the heat source. The inner liner is made of stainless steel with a high thermal conductivity. When the heat transfer oil circulates in the cavity 11, heat is evenly transferred to the potato starch layer through the inner liner wall. Combined with the rotation of the cylinder 2, the surface temperature fluctuation of the inner liner is controlled within ±2℃, avoiding local overheating or underheating. Under the same drying conditions (heat transfer oil temperature 120℃, cylinder 2 rotation speed 2 rpm), compared with the traditional static drying device, this embodiment can shorten the potato starch drying time by 40% and reduce the standard deviation of moisture content from 1.8% to 0.5%, significantly improving drying uniformity.

[0029] Overall workflow: First, open the top cover 1 of the feed port, pour the potato starch to be dried into the inner liner, close the top cover 1 and tighten the bolts, then start the circulation pump and heater. High-temperature heat transfer oil enters the cavity 11 through the oil inlet pipe 7 to heat the inner liner and potato starch. The cylinder 2 rotates slowly under the drive of the motor 5 and the reducer 4 to ensure that the potato starch is heated evenly. The pressure of the inner liner is monitored in real time with the help of the breathing component. The pressure balance is maintained by discharging or drawing in air. At the same time, the dehumidifier 20 ensures that the gas is dry. After drying is completed, stop heating and rotation, and open the butterfly valve 12 to discharge the potato starch.

[0030] This embodiment, through the synergistic effect of the heating and breathing components and the rotating design of the cylinder 2, effectively improves the drying efficiency and product quality of potato starch, and is suitable for large-scale potato starch processing scenarios.

Claims

1. A potato flour rotary drying apparatus, characterized by: include frame; The cylinder is placed horizontally on the upper part of the frame, and its two ends are connected to the frame through bearing seats to achieve rotation. The cylinder has a double-layer structure, including an inner liner and an outer shell. The inner liner is used to hold potato starch, and a cavity is formed between the outer shell and the inner liner. Heating components, including: The oil inlet pipe and oil return pipe connect the cavity; A heat transfer oil circulation pump and heater that connects the oil inlet pipe and the oil return pipe; A secondary cavity is located outside the cavity and connected to the cavity at both ends, with one end of the oil return pipe extending into the secondary cavity; Breathing components, including: An air duct that extends into the inner liner; A dehumidifier connected to the air duct is used to regulate the humidity and pressure of the gas inside the cylinder; The drive system, including a motor and a reducer, drives the cylinder to rotate through a transmission mechanism.

2. The potato powder rotary drying apparatus according to claim 1, characterized by: Multiple spiral or annular baffles are arranged at intervals within the cavity, and the baffles do not completely block the cavity.

3. The potato powder rotary drying apparatus according to claim 1, characterized by: The heating assembly further includes a first bushing and a first rotary joint; the first bushing is fixed to the frame and connected to the outer shell, and a first flow channel communicating with the cavity is opened inside it; the first rotary joint is installed at the end of the first bushing and connected to the oil inlet pipe and the oil return pipe.

4. The potato powder rotary drying apparatus according to claim 1, characterized by: The inlet end of the air guide pipe is equipped with an air guide cover with a mesh, the mesh diameter being smaller than the potato starch particle size.

5. The potato powder rotary drying apparatus according to claim 1, characterized by: The desiccant is a silicone container filled with color-changing silicone particles.

6. The potato powder rotary drying apparatus according to claim 1, characterized by: The speed reducer is a worm gear reducer.

7. The potato powder rotary drying apparatus according to claim 1, characterized by: The transmission mechanism includes: The first pulley installed on the motor output shaft; The second pulley is installed on the input shaft of the reducer; The first belt connecting the first pulley and the second pulley; The third pulley is installed on the output shaft of the reducer; The fourth pulley is fixed to the outer circumference of the second bushing; The second belt connects the third pulley and the fourth pulley.

8. The potato powder rotary drying apparatus according to claim 1, characterized by: The motor can rotate in both directions, and the rotation direction of the cylinder can be switched periodically by the controller.

9. The potato powder rotary drying apparatus according to claim 1, characterized by: The cylinder has an inlet with a flip-up cover at one end and an outlet controlled by a butterfly valve at the other end.

10. The potato powder rotary drying apparatus according to claim 1, characterized in that: The inner liner is made of stainless steel, and the outer shell is wrapped with insulation cotton.

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