Rice sterilization device and sterilization method based on pulse sterilization principle

Abstract

The rice sterilization device comprises a sterilization chamber, a steam injection pipe, a shielding part, a uniform distribution part and a wall-attached flow guide part, wherein the shielding part comprises a diversion conical cap and is used for shielding the front surface of an inlet and enabling steam to enter the chamber from the upper layer of the sterilization chamber through collision and transverse overflow diffusion; the at least one layer of buffer screen plate is used for buffering the flow rate of steam and uniformly distributing and guiding the steam downwards; the splitter plate is a boundary between the upper layer and the lower layer in the sterilization chamber and conducts wall-attached flow guide on steam, a wall-attached opening is formed in the side edge, attached to the inner wall of the sterilization chamber, of the splitter plate, and the steam flows downwards into the lower layer, containing the rice raw materials, of the sterilization chamber only from the wall-attached opening; according to the rice sterilization device based on the pulse sterilization principle, the flow dividing conical cap, the buffering net plate and the flow dividing plate are arranged in the rice sterilization device to conduct pressure reduction, uniform distribution and flow dividing on steam, and temperature distribution in the cavity rapidly tends to be stable while the situation that the steam entering at a high speed directly impacts rice is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of food processing equipment, and in particular to a rice sterilizing device and a sterilizing method based on the pulsation sterilization principle. Background Art

[0002] Convenience foods allow consumers to eat food that can be eaten in a very short time by simply heating or preparing it. This type of food is designed to provide a quick and convenient dietary solution, especially suitable for busy lifestyles or when food needs to be obtained quickly in specific situations (such as traveling and camping). With the improvement of living standards and the accelerated pace of work, people's demand for convenience foods is increasing. Aseptic rice provides consumers with a fast, safe and convenient staple food option, especially for those who are looking for a simple dietary solution;

[0003] Aseptic rice, also known as sterile instant rice, is a specially processed instant rice product. This type of rice is usually heated to a high enough temperature during the production process to kill all possible microorganisms (including bacteria, molds and yeasts, etc.), and then packaged under aseptic conditions to ensure that there are no living microorganisms inside the product and it can be stored for a long time without refrigeration.

[0004] High-pressure steam sterilization is a wet heat sterilization method that uses saturated steam under high temperature and high pressure to kill microorganisms and their spores. This method can provide efficient sterilization effects and is widely used in laboratory equipment, medical supplies and other fields. However, it faces some problems when applied to the sterilization of rice. The rice is placed in a container. When high-pressure steam is introduced, the large pressure difference can easily disperse the rice grains. In this case, the steam inflow speed must be greatly controlled, which greatly slows down the sterilization speed and is difficult to meet production needs.

[0005] In view of the above, it is necessary to propose a rice sterilization device and a sterilization method based on the pulsation sterilization principle to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects in the prior art and provide a rice sterilizing device and a sterilizing method based on the pulsation sterilization principle.

[0007] To achieve the above object, the technical solution of the present invention is as follows: a rice sterilizing device based on the pulsation sterilization principle, The sterilization chamber includes a sterilization chamber for containing the sterilized rice raw material and providing a chamber isolated from the outside to facilitate the rapid introduction and diffusion of steam; Steam injection pipe: connected to the sterilization chamber and provides steam of predetermined temperature and pressure; The shielding, uniform distribution and wall-adhering flow guide part is a multi-layer structure arranged in the upper part of the sterilization chamber, including a diverter cone cap, which is arranged opposite to the inlet of the steam injection pipe, used to shield the front of the inlet and allow the steam to enter the chamber from the upper layer of the sterilization chamber through collision and lateral overflow diffusion; at least one layer of buffer mesh plate, which is used to buffer the steam flow rate and uniformly guide it downward; a diverter plate, which is the boundary between the upper and lower layers in the sterilization chamber, and guides the steam to the wall. The diverter plate is provided with a wall-adhering opening on the side close to the inner wall of the sterilization chamber, and the steam only flows downward from the wall-adhering opening into the lower layer of the sterilization chamber containing the rice raw material; Pressure release pipe: connected to the sterilization chamber for rapid pressure relief in the sterilization chamber, and it is controlled by alternate opening and closing with the steam injection pipe; An air exhaust valve is also included, which is used to exhaust air and retain steam when steam is injected, so that the chamber can heat up quickly.

[0008] Furthermore, the sterilization chamber includes a cylindrical box body, at least one end of which is provided with a raw material port for feeding and discharging rice raw materials, the raw material port is provided with a closing mechanism, and the top wall of the cylindrical box body is connected with a plurality of steam injection pipes and pressure release pipes, and the steam injection pipes and the pressure release pipes are alternately arranged.

[0009] Furthermore, the diversion cone cap is in the shape of a disc, and an upwardly arched conical convex portion is provided inside the disc, and the edge of the conical convex portion circumferentially forms an overflow ring with an upwardly tilted distal end, and the conical convex portion and the overflow ring are connected at the low point to form a V-shaped circular groove.

[0010] Furthermore, a plurality of groove bottom openings are evenly distributed around the circumference of the V-shaped circular groove, and a plurality of Z-shaped brackets are arranged around the circumference of the diverter cone cap to be mounted on the inner top wall of the cylindrical box body and directly facing the inlet. The radius of the inlet is R1, and the bottom radius of the conical convex part is R2, so that R2<R1<R2.

[0011] Furthermore, the length and width of the buffer mesh plate are the same as those of the cylindrical box body to form a partition mesh on the upper layer of the sterilization chamber. The buffer mesh plate is arranged on the lower side of the diversion cone cap, is in the shape of a flat plate, and has a plurality of through mesh holes evenly arranged on its surface.

[0012] Furthermore, a material tray is provided in the lower layer of the sterilization chamber, and a plurality of rice placement positions are provided on the material tray. Each rice placement position corresponds to a sterilization position in the sterilization chamber, and a monitoring component is provided on the lower side of each sterilization position. The monitoring component includes a temperature sensor and a pressure sensor.

[0013] Furthermore, the diverter plate has a structure that is high in the middle and low on both sides. The diverter plate is arched upward in an arc shape in the middle of the axial direction, and a number of wall-adhering openings are formed at even intervals at the low points on both sides. The wall-adhering openings are punched out on both sides of the diverter plate, and an open side plate is formed on the inner side. The high point side of the open side plate is connected to the diverter plate, and the low point side faces the inner wall of the cylindrical box. The open side plate is bent downward and offset from the diverter plate to form an opening and guide the steam to flow down along the wall.

[0014] Furthermore, a reinforcing rib frame is provided perpendicularly to the outer wall of the cylindrical box body, a plurality of reinforcing rib frames are provided and are evenly arranged along the length direction of the cylindrical box body, and the reinforcing rib frames are arranged in a ring shape on the outer periphery of the cylindrical box body.

[0015] A rice sterilization device and sterilization method based on the pulsation sterilization principle, comprising the following steps: S1: The rice to be sterilized is divided into containers and placed on the rice placement positions respectively, the material tray is sent into the sterilization chamber, and the door closing mechanism is closed to seal the sterilization chamber; S2: Temperature and pressure increase process: keep the pressure release pipe and condensate discharge pipe closed, open the steam injection pipe and quickly fill the steam to increase the temperature and pressure of the sterilization chamber; S3: Insulation and pressure maintenance process: The temperature and pressure in the chamber are detected by the monitoring component to reach the preset value, and the steam injection pipe is closed. When the pressure and temperature drop in the middle of the process, the steam injection pipe is opened intermittently to replenish and maintain the set pressure for a period of time; S4: Pressure relief and condensate discharge process: keep the steam injection pipe closed, open the pressure release pipe and condensate discharge pipe, and quickly discharge the steam and bottom condensate in the sterilization chamber; S5: When the pressure in the chamber is close to normal pressure, close the pressure release pipe and the condensate drain pipe, and repeat steps S2, S3, S4, and S5 for multiple times; S6: Open the door closing mechanism and take out the material tray.

[0016] Furthermore, the sterilization method lasts for 40 to 60 seconds, during which steps S2, S3, S4, and S5 are cycled in the sterilization chamber at least 4 times; in the S2 step, the temperature and pressure increase process takes no more than 6 seconds, the pressure in the sterilization chamber is 4 to 6 bar, and the temperature in the sterilization chamber reaches 135 to 150°C; the time for heat preservation and pressure maintenance in the S3 step is 4 to 6 seconds; and the time for pressure relief and condensation removal in the S4 step is no more than 2 seconds.

[0017] The advantages and beneficial effects of the present invention are: 1. A rice sterilizing device based on the pulsation sterilization principle of the present invention is provided with a diverter cone cap, a buffer mesh plate and a diverter plate inside to reduce the pressure, distribute and divert the steam, so as to prevent the high-speed steam from directly impacting the rice and make the temperature distribution in the cavity quickly tend to be stable.

[0018] 2. The presence of air in the steam system seriously affects the heat transfer efficiency of the system. In order to quickly heat up the chamber, the air must be removed. The steam exhaust valve is used for the first time in rice sterilization equipment. When steam is passed, the air is automatically exhausted to retain the steam. If non-condensable gases such as air are left, the heat transfer resistance will increase significantly, affecting the heating efficiency. Therefore, when steam is passed, the steam heating space needs to be exhausted. This can not only quickly increase the chamber temperature and shorten the cycle time, but also avoid the original air in the steam heating chamber, thereby reducing energy waste.

[0019] 3. Ultra-high temperature instantaneous sterilization technology is used to quickly raise the temperature in the cavity to 135-150°C in a short period of time. The sensitivity of microorganisms to high temperatures is much greater than that of rice. This allows for effective sterilization in a short time, shortening the sterilization cycle and increasing the production capacity of the entire line, while retaining the nutrition and flavor of rice to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the sterilization process based on the pulsation sterilization principle in the present invention; Figure 2 It is an axonometric diagram of a rice sterilizing device based on the pulsation sterilization principle in the present invention; Figure 3 It is a longitudinal cross-sectional schematic diagram of the rice sterilizing device in the present invention; Figure 4 is an internal steam injection distribution diagram of the rice sterilizing device of the present invention; Figure 5 is an exploded view of the rice sterilizing device of the present invention; Figure 6 It is a structural schematic diagram of the diverter cone cap in the present invention; Figure 7 It is a schematic diagram of the longitudinal cross-section structure of the diverter cone cap in the present invention; In the figure: 1. Sterilization chamber; 2. Steam injection pipe; 3. Diverter cone cap; 4. Inlet; 5. Buffer mesh plate; 6. Diverter plate; 7. Pressure release pipe; 8. Cylindrical box; 9. Raw material port; 10. Conical convex part; 11. Overflow ring; 12. V-shaped circular groove; 13. Groove bottom opening; 15. Z-shaped bracket; 16. Material tray; 17. Rice placement position; 18. Sterilization position; 19. Temperature sensor; 20. Pressure sensor; 21. Wall opening; 22. Opening side panel; 23. Reinforced rib frame; 24. Air exhaust valve; 25. Door closing mechanism; 26. Condensate exhaust pipeline. DETAILED DESCRIPTION

[0021] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0022] A rice sterilization device based on the pulsation sterilization principle, such as Figures 1 to 7 As shown, The sterilization chamber 1 includes a sterilization chamber 1 for accommodating the sterilized rice raw material and providing a chamber isolated from the outside to facilitate the rapid entry and diffusion of steam; the sterilization chamber 1 includes a cylindrical box body 8, at least one end of which is provided with a raw material port 9 for entering and exiting the rice raw material, and the raw material port 9 is provided with a closing mechanism 25. Preferably, a reinforcing rib frame 23 is provided perpendicular to the outer wall of the cylindrical box body 8, and a plurality of reinforcing rib frames 23 are provided and are evenly arranged along the length direction of the cylindrical box body 8, and the reinforcing rib frames 23 are arranged in a ring shape on the outer periphery of the cylindrical box body 8. The reinforcing rib frame 23 can reinforce the shape of the cylindrical box body 8 to prevent the box body from being deformed under repeated pressure.

[0023] The top wall of the cylindrical box 8 is connected with a plurality of steam injection pipes 2 and pressure release pipes 7, and the steam injection pipes 2 and the pressure release pipes 7 are arranged alternately. As shown in the figure, in this embodiment, a long cylindrical structure with a rectangular cross section is used as the cylindrical box 8, and its internal space is used to place the rice raw material to be sterilized. The rectangular cylindrical box 8 is convenient for rapid steam injection without dead corners. In this embodiment, five circular holes are arranged on the top surface of the cylindrical box 8 for connecting the steam injection pipe 2 and the pressure release pipe 7, as shown in FIG. Figure 1 As shown, two of them are steam injection pipes 2, and the other three are pressure release pipes 7; raw material ports 9 can be respectively set at both ends of the cylindrical box 8, or one end can be set as the raw material port 9; when the raw material ports 9 are set at both ends, it is convenient to feed from one side and discharge from the other side, which is more conducive to the production speed of the assembly line; when the raw material port 9 is set at one end, only this end is used for feeding and discharging, which has the advantage of reducing sealing components, which is conducive to reducing equipment costs and reducing the probability of steam leakage.

[0024] Steam injection pipe 2: connected to the sterilization chamber 1 and providing steam of a predetermined temperature and pressure; pressure release pipe 7: connected to the sterilization chamber 1 for rapid pressure relief in the sterilization chamber 1, and alternately opened and closed with the steam injection pipe 2; it can be understood that the steam injection pipe 2 is connected to a gas source providing high-pressure steam, and an air intake automatic control valve for automatically controlling the opening or closing of the pipeline is provided on the steam injection pipe 2, and similarly, an exhaust automatic control valve is provided on the pressure release pipe 7, and the steam injection pipe 2 and the pressure release pipe 7 can be automatically controlled to be alternately opened or closed by setting the two automatic control valves; Figure 3 As shown, the middle pipe on the top of the cylindrical box 8 is a pressure release pipe 7, and a steam injection pipe 2 is arranged on both sides thereof, and then two pressure release pipes 7 are arranged on the outside of the two steam injection pipes 2 respectively. This distribution method is more conducive to the uniform distribution of steam and can also release pressure more quickly.

[0025] The shielding, uniform distribution and wall-adhering flow guide part is a multi-layer structure arranged at the upper part of the sterilization chamber 1, including a diverter cone cap 3, which is arranged opposite to the inlet 4 of the steam injection pipe 2, and is used to shield the front of the inlet 4 and allow the steam to collide, overflow and diffuse horizontally from the upper layer of the sterilization chamber 1 into the chamber; specifically, Figure 3 As shown, splitter cone caps 3 are respectively provided at the inlet ports 4 of the two steam injection pipes 2 .

[0026] Specifically, Figures 5 to 7 As shown, the diverter cone cap 3 is in the shape of a disc, and an upwardly arched cone convex part 10 is provided inside the disc, and the edge of the cone convex part 10 forms an overflow ring 11 with an upwardly tilted far end. The cone convex part 10 and the overflow ring 11 are connected at the low point to form a V-shaped circular groove 12. When steam is injected, it first touches the cone convex part 10, so that the steam can be evenly dispersed around by the cone tip, and the V-shaped circular groove 12 forms a folded edge tilted upward, which has the effect of secondary buffering for the passing steam and diverting it upward, greatly slowing down the impact of the steam entering, and preventing the steam from entering quickly and blowing away the rice grains. Specifically, a plurality of Z-shaped brackets 15 are provided around the diverter cone cap 3 to install it on the inner top wall of the cylindrical box body 8 and directly opposite the inlet 4. In this embodiment, three Z-shaped brackets 15 are provided, and the three Z-shaped brackets 15 are arranged around the inlet 4. One end of the Z-shaped bracket 15 is welded to the inner top wall of the cylindrical box body 8, and the other side can hold up the diverter cone cap 3, while keeping a certain distance between the diverter cone cap 3 and the inlet 4 to facilitate the lateral flow of steam.

[0027] Furthermore, a plurality of groove bottom openings 13 are evenly distributed around the circumference of the V-shaped circular groove 12. Considering that the setting of the diverter cone cap 3 blocks the steam distribution amount at its bottom, the groove bottom openings 13 are set. The groove bottom openings 13 allow the steam to pass through the bottom of the V-shaped circular groove 12 and disperse it around the bottom of the diverter cone cap 3; in order to achieve a better steam distribution effect, it also has the function of avoiding the accumulation of condensed water, such as Figure 7 As shown, the radius of the inlet 4 is R1, and the bottom radius of the conical convex portion 10 is R2, so that 1 / 2R2<R1<R2.

[0028] At least one layer of buffer screen 5, such as Figure 4 , 5As shown, in this embodiment, only one layer of buffer mesh 5 is set as an example. Specifically, it is used to buffer the steam flow rate and evenly guide the steam downward. After the high-temperature and high-pressure steam enters from the top of the sterilization chamber 1, it first collides with the diverter cone cap 3 to form a lateral flow and quickly fills the upper layer of the buffer mesh 5 of the sterilization chamber 1. The buffer mesh 5 is densely provided with a number of holes, so that the filled steam flows downward from the holes. Specifically, the length and width of the buffer mesh 5 are the same as those of the cylindrical box 8 to form a partition net on the upper layer of the sterilization chamber 1. The buffer mesh 5 is set on the lower side of the diverter cone cap 3. It is in the shape of a flat plate and has a number of through mesh holes evenly arranged on its surface. In this way, the buffer mesh 5 can be used to form a three-level buffer for the steam and achieve an effect of evenly distributing the steam;

[0029] The diverter plate 6 is the boundary between the upper and lower layers of the sterilization chamber 1. It guides the steam along the wall. The diverter plate 6 is provided with a wall-adhering opening 21 on the side close to the inner wall of the sterilization chamber 1. The steam only flows downward from the wall-adhering opening 21 to the lower layer of the sterilization chamber 1 containing the rice raw material. As a key component to avoid impacting the rice, it blocks the opening above the rice container, greatly reducing the risk of direct impact of the steam on the rice, thereby ensuring that the rice is not dispersed. Figure 4 , 5 As shown, the diverter plate 6 is a structure that is high in the middle and low on both sides. The diverter plate 6 is arched upward in an arc shape in the middle of the axial direction, and a number of wall-adhering openings 21 are formed at even intervals at the low points on both sides. The wall-adhering openings 21 are punched out on both sides of the diverter plate 6, and an opening side plate 22 is formed on the inner side thereof. The high point side of the opening side plate 22 is connected to the diverter plate 6, and the low point side faces the inner wall of the cylindrical box body 8. The opening side plate 22 is bent downward and offset from the diverter plate 6 to form an opening and guide the steam to flow down along the wall. After the steam is evenly distributed by the buffer mesh 5, the steam goes down and touches the arc-shaped arch, and then is divided to both sides, and finally is guided to flow downward by the wall-adhering opening 21, so that the steam forms an effect of flowing down along the wall, and an opening side plate 22 is further provided to guide the steam to the lower side of the opening of the rice container, that is, the lower edge of the opening side plate 22 is lower than the opening edge of the rice container; thereby, it can be ensured that the rice is not blown away when the steam enters, and at the same time, a high steam introduction speed is maintained, thereby greatly improving the production rhythm.

[0030] The diverter cone cap, buffer mesh plate 5 and diverter plate 6 arranged inside reduce the pressure, distribute and divert the steam, preventing the high-speed steam from directly impacting the rice and making the temperature distribution in the cavity quickly stabilize; It also includes an air exhaust valve 24, which is commercially available and installed at both ends of the sterilization chamber. The air exhaust valve 24 is used to exhaust air and retain steam when steam is injected, so that the chamber is heated quickly.

[0031] Specifically, the reason why the air exhaust valve 24 retains steam: the air exhaust valve 24 plays a vital role in the steam system. Its main purpose is to remove air and other non-condensable gases in the system. These gases can cause problems such as unstable steam system pressure, equipment corrosion, and pipeline blockage, which in turn affects the efficiency and stability of the system. The air exhaust valve 24 can effectively prevent equipment corrosion, reduce noise, and improve the operating efficiency of the system by timely removing air from the system.

[0032] ‌Working principle of the air exhaust valve 24‌: The working principle of the air exhaust valve 24 is based on Dalton's law of partial pressure. When there is air in the steam, the pressure on the liquid capsule in the air exhaust valve 24 is the total pressure of the mixed gas of steam and air. Since the temperature of the mixed gas is lower than the saturation temperature corresponding to the pressure on the liquid capsule, the liquid in the liquid capsule will not boil, the exhaust port is in an open state, and the air is discharged. When the air is discharged, the pressure on the liquid capsule becomes pure steam pressure, the liquid in the liquid capsule boils and the volume increases, driving the valve core to move and close the exhaust port. In this way, the air exhaust valve 24 can automatically close when it is lower than the saturation temperature of the steam to ensure the normal circulation of steam‌.

[0033] ‌Installation location of exhaust valve 24‌: When selecting an exhaust valve, it is recommended to give priority to the thermostatic exhaust valve 24 and install it in an area where the steam can easily push the air when the system is turned on. This ensures that the air can be effectively exhausted when the steam flows, avoiding accumulation in other parts of the system‌. Specifically, in this embodiment, if Figure 3 As shown, the exhaust valve 24 is set at the high point of both ends of the sterilization chamber 1; the exhaust valve 24 is used to quickly heat up. The presence of air in the steam system seriously affects the heat transfer efficiency of the system. In order to quickly heat up the chamber, the air must be removed. The steam exhaust valve 24 is used for the first time in the rice sterilization equipment. When the steam is turned on, the air is automatically exhausted to retain the steam, which can not only quickly increase the chamber temperature and shorten the cycle time, but also avoid steam heating the original air in the chamber, thereby reducing energy waste.

[0034] Further, such as Figure 5 As shown, a material tray 16 is provided in the lower layer of the sterilization chamber 1, and a plurality of rice placement positions 17 are provided on the material tray 16, and each rice placement position 17 forms a corresponding sterilization position 18 in the sterilization chamber 1. Figure 2 As shown, the two sterilization positions 18 are separated by a reinforcing rib frame 23, and a monitoring component is provided on the lower side of each sterilization position 18, and the monitoring component includes a temperature sensor 19 and a pressure sensor 20. The internal conditions of the sterilization chamber 1 can be accurately monitored and precisely adjusted by setting the monitoring component.

[0035] A rice sterilization device and sterilization method based on the pulsation sterilization principle, such as Figure 1As shown, the following steps are included: S1: The rice to be sterilized is divided into containers and placed on the rice placement positions 17 respectively, the material tray 16 is sent into the sterilization chamber 1, and the door closing mechanism 25 is closed to seal the sterilization chamber 1; S2: Temperature and pressure increase process: keep the pressure release pipe 7 and the condensate discharge pipe closed, open the steam injection pipe 2 to quickly fill the steam, and increase the temperature and pressure of the sterilization chamber 1; the temperature and pressure increase process takes no more than 6 seconds, the pressure in the sterilization chamber 1 is 4-6 bar, and the temperature in the sterilization chamber 1 reaches 135-150°C; S3: Insulation and pressure holding process: The temperature and pressure in the chamber are detected by the monitoring component to reach the preset value, and the steam injection pipe 2 is closed. When the pressure and temperature drop in the middle of the process, the steam injection pipe 2 is opened intermittently to replenish and maintain the set pressure for a period of time; the insulation and pressure holding time is 4~6s; S4: Pressure relief and condensate discharge process: keep the steam injection pipe 2 closed, open the pressure release pipe 7 and the condensate discharge pipe, and quickly discharge the steam and bottom condensate in the sterilization chamber 1; the time for pressure relief and condensate discharge shall not exceed 2s; S5: When the pressure in the chamber is close to normal pressure, close the pressure release pipe 7 and the condensate drain pipe, and repeat steps S2, S3, S4, and S5 for multiple times; S6: Open the door closing mechanism 25 and take out the material tray 16.

[0036] Specifically, the sterilization method lasts for 40 to 60 seconds, during which steps S2, S3, S4, and S5 are cycled at least 4 times in the sterilization chamber 1. The ultra-high temperature instantaneous sterilization technology is used to quickly increase the temperature in the chamber to 135 to 150°C in a short period of time. The microorganisms are much more sensitive to high temperatures than rice, which can effectively sterilize in a short time, shorten the sterilization cycle, and improve the production capacity of the entire line, while retaining the nutrition and flavor of rice to the greatest extent.

[0037] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A rice sterilizing device based on the pulsation sterilization principle, characterized in that: It comprises a sterilization chamber (1): used to contain the rice material to be sterilized and to provide a chamber isolated from the outside to facilitate the rapid introduction and diffusion of steam; Steam injection pipe (2) connected to the sterilization chamber (1) and providing steam at a predetermined temperature and pressure; The shielding, uniform distribution and wall-adhering flow guiding part is a multi-layer structure arranged at the upper part of the sterilization chamber (1), comprising a diverter cone cap (3) arranged opposite to the inlet (4) of the steam injection pipe (2), used to shield the front of the inlet (4) and allow the steam to enter the chamber from the upper layer of the sterilization chamber (1) through collision and lateral overflow diffusion; at least one layer of buffer mesh plate (5), used to buffer the steam flow rate and uniformly guide the steam downward; a diverter plate (6), which is a boundary between the upper and lower layers of the sterilization chamber (1) and guides the steam to the wall; the diverter plate (6) is provided with a wall-adhering opening (21) on the side close to the inner wall of the sterilization chamber (1), and the steam only flows downward from the wall-adhering opening (21) into the lower layer of the sterilization chamber (1) containing the rice raw material; A pressure release pipe (7) is connected to the sterilization chamber (1) and is used for rapid pressure relief in the sterilization chamber (1). The pressure release pipe (7) and the steam injection pipe (2) are alternately opened and closed for control.

2. A rice sterilizing device based on the pulsation sterilization principle according to claim 1, characterized in that: The sterilization chamber (1) comprises a cylindrical box body (8), at least one end of which is provided with a raw material port (9) for feeding and discharging rice raw materials, the raw material port (9) being provided with a door closing mechanism (25), a top wall of the cylindrical box body (8) being connected with a plurality of steam injection pipes (2) and pressure release pipes (7), and the steam injection pipes (2) and the pressure release pipes (7) being arranged alternately; and an air exhaust valve (24) is further provided, which is used to exhaust air and retain steam during steam injection, so as to rapidly heat the chamber.

3. A rice sterilizing device based on the pulsation sterilization principle according to claim 2, characterized in that: The diverter cone cap (3) is in the shape of a disk, and an upwardly arched conical convex portion (10) is provided inside the disk. The edge of the conical convex portion (10) forms an overflow ring (11) with an upwardly curved distal end. The conical convex portion (10) and the overflow ring (11) are connected at a low point to form a V-shaped circular groove (12).

4. A rice sterilizing device based on the pulsation sterilization principle according to claim 3, characterized in that: A plurality of groove bottom openings (13) are evenly distributed around the circumference of the V-shaped circular groove (12), and a plurality of Z-shaped brackets (15) are provided around the circumference of the diverter cone cap (3) to be mounted on the inner top wall of the cylindrical box body (8) and facing the inlet (4). The radius of the inlet (4) is R1, and the bottom radius of the conical convex portion (10) is R2, so that R2<R1<R2.

5. A rice sterilizing device based on the pulsation sterilization principle according to claim 4, characterized in that: The buffer mesh plate (5) has the same length and width as the cylindrical box body (8) and constitutes a partition mesh on the upper layer of the sterilization chamber (1). The buffer mesh plate (5) is arranged on the lower side of the diversion cone cap (3), is in the shape of a flat plate, and has a plurality of through mesh holes evenly arranged on its surface.

6. A rice sterilizing device based on the pulsation sterilization principle according to claim 5, characterized in that: A material tray (16) is provided in the lower layer of the sterilization chamber (1), and a plurality of rice placement positions (17) are provided on the material tray (16). Each rice placement position (17) forms a corresponding sterilization bin (18) in the sterilization chamber (1). A monitoring component is provided on the lower side of each sterilization bin (18), and the monitoring component comprises a temperature sensor (19) and a pressure sensor (20).

7. A rice sterilizing device based on the pulsation sterilization principle according to claim 6, characterized in that: The diverter plate (6) is a structure with a high middle and low sides. The diverter plate (6) is arched upward in an arc shape in the middle of the axial direction, and a plurality of wall-adhering openings (21) are formed at even intervals at low positions on both sides. The wall-adhering openings (21) are punched and formed on both sides of the diverter plate (6), and an opening side plate (22) is formed on the inner side thereof. The high point side of the opening side plate (22) is connected to the diverter plate (6), and the low point side faces the inner wall of the cylindrical box body (8). The opening side plate (22) is bent downward to be offset from the diverter plate (6) to form an opening and guide the steam to flow down along the wall.

8. A rice sterilizing device based on the pulsation sterilization principle according to claim 2, characterized in that: A reinforcing rib frame (23) is provided perpendicularly to the outer wall of the cylindrical box body (8); a plurality of reinforcing rib frames (23) are provided and are evenly arranged along the length direction of the cylindrical box body (8); and the reinforcing rib frames (23) are arranged in a ring shape on the outer periphery of the cylindrical box body (8).

9. A rice sterilizing device and sterilizing method based on the pulsation sterilization principle according to claim 1, characterized in that: The following steps are involved: S1: The rice to be sterilized is divided into containers and placed on the rice placement positions (17) respectively, the material tray (16) is sent into the sterilization chamber (1), and the door closing mechanism (25) is closed to seal the sterilization chamber (1); S2: Temperature and pressure increase process: keep the pressure release pipe (7) and the condensate discharge pipe closed, open the steam injection pipe (2) to quickly fill in steam, and increase the temperature and pressure of the sterilization chamber (1); S3: heat preservation and pressure preservation process: the temperature and pressure in the chamber are detected by the monitoring component to reach the preset value, and the steam injection pipe (2) is closed. If the pressure and temperature drop during the process, the steam injection pipe (2) is opened intermittently to replenish the steam, and the set pressure is maintained for a period of time; S4: pressure relief and condensate discharge process: keep the steam injection pipe (2) closed, open the pressure release pipe (7) and the condensate discharge pipe, and quickly discharge the steam and bottom condensate in the sterilization chamber (1); S5: When the pressure in the chamber is close to normal pressure, the pressure release pipe (7) and the condensate discharge pipe are closed, and steps S2, S3, S4 and S5 are repeated multiple times; S6: Open the door closing mechanism (25) and take out the material tray (16).

10. A rice sterilizing device and sterilizing method based on the pulsation sterilization principle according to claim 9, characterized in that: The sterilization method lasts for 40 to 60 seconds, during which steps S2, S3, S4 and S5 are cycled at least four times in the sterilization chamber (1); In the step S2, the temperature and pressure increase process takes no more than 6 seconds, the pressure in the sterilization chamber (1) is between 4 and 6 bar, and the temperature in the sterilization chamber (1) reaches 135 to 150° C.; the time for heat preservation and pressure maintenance in the step S3 is 4 to 6 seconds; and the time for pressure relief and condensation removal in the step S4 is no more than 2 seconds.

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