Ultrahigh-temperature instant sterilization steam direct injection mixer

Abstract

The invention discloses an ultrahigh-temperature instant sterilization steam direct injection mixer which comprises a steam inlet module, a spray head main body module, a jet flow module and an outlet module, and the steam inlet module and the outlet module are connected with the spray head main body module; and the jet flow module is clamped and fixed with the spray head main body module through the outlet module. Aiming at the temperature rise working condition of pasteurization, a better gas-liquid mixing effect can be achieved, meanwhile, the temperature of mixed materials can be more uniform, a better sterilization effect can be achieved, and better temperature stability is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of food sterilization equipment, and in particular to an ultra-high temperature instantaneous sterilization steam direct injection mixer. Background Art

[0002] The main purpose of heat treatment of milk is to kill microorganisms and inactivate enzymes. The effectiveness of heat treatment and its impact on product quality are mainly related to the temperature-time combination, the heating method used and the pretreatment conditions of milk. At present, there are four main types of heat sterilization: preheating sterilization, pasteurization, ultra-high temperature instantaneous sterilization and maintenance sterilization. After a long period of scientific experiments and practical exploration, countries around the world have now formed a relatively unified production model, mainly pasteurization and ultra-high temperature instantaneous sterilization (UHT) sterilization. Two forms of heat processing.

[0003] In addition, an advanced sterilization method has emerged: direct steam injection sterilization. This technology is to inject steam directly into the milk to increase the temperature, and then pass it through the sterilization temperature pipe at high pressure to achieve instant sterilization. The core breakthrough of this technology is to retain the natural nutritional active protein in milk to the maximum extent. The direct steam injection sterilization process (infection, referred to as INF) has high heat transfer efficiency because of direct contact with the heating medium (steam) and then immediate cooling through vacuum, thereby limiting the product quality loss caused by excessive heat exposure. The main principle of direct steam injection sterilization is to fully mix the liquid phase fluid to be sterilized with the steam phase fluid, and use the high temperature of steam to sterilize the liquid phase fluid. It mainly includes two categories: (1) steam immersion sterilization (steam infusion): spraying the liquid phase fluid into a steam bath for sterilization; (2) steam injection sterilization (steam injection): the liquid phase is first formed into a ring jet, and then mixed with the injected steam for sterilization. Steam direct injection (INF) sterilizes directly. Due to the direct contact between the material and the heating medium (steam), the heat transfer efficiency is high, which greatly reduces the product quality loss caused by excessive heat exposure and can greatly improve the active nutrition of the product. At the same time, the direct heat transfer of steam also greatly reduces thermal damage and slagging due to the absence of heat transfer surface, avoiding the occurrence of pipe sticking.

[0004] At present, the direct steam injection sterilization technology mainly adopts a mixer structure such as that in CN101969782B to achieve the mixing and heat transfer of steam and materials. However, the mixing of steam and materials in this structure is only for a very short time through the annular slit. After the steam enters the material, it will form bubbles of larger size, which greatly reduces the speed of phase change heat transfer and cannot achieve full and complete mixing and heat transfer, resulting in uneven heating of the material and the local material temperature is lower than the sterilization temperature, affecting the sterilization effect. Therefore, when using the direct steam injection sterilization process, the sterilization temperature is usually 3-5°C higher than the traditional indirect sterilization temperature to ensure the sterilization effect. However, a higher sterilization temperature will also cause additional heating of the material, resulting in the loss of active business and sensory flavor. This is also one of the reasons why the application of direct steam injection sterilization technology is currently limited. Summary of the invention

[0005] In view of the problem of uneven gas-liquid mixing in existing steam direct injection mixers, the present invention proposes an ultra-high temperature instantaneous sterilization steam direct injection mixer, comprising a steam inlet module, a nozzle main body module, a jet module, and an outlet module. The steam inlet module and the outlet module are respectively connected to the nozzle main body module; the jet module is clamped and fixed to the nozzle main body module through the outlet module.

[0006] Furthermore, the steam inlet module and the outlet module are respectively fastened to the nozzle main body module through threads, and the jet module is clamped and fixed when the outlet module and the nozzle main body module are fastened through threads.

[0007] Furthermore, the space between the steam inlet module and the jet module forms a vortex mixing chamber, and the liquid material inlet is connected to the vortex mixing chamber.

[0008] Furthermore, the steam inlet module includes a steam inlet, a compression section, a contraction accelerator, and a steam jet nozzle, and the diameter of the compression section is smaller than that of the steam inlet; the contraction accelerator is a conical structure, which is used to accelerate the steam after entering; the steam is ejected through the steam jet nozzle in the form of a supersonic jet and passes through the vortex mixing chamber.

[0009] Furthermore, a liquid material inlet is provided above the vortex mixing chamber, for liquid material to enter the vortex mixing chamber from the liquid material inlet.

[0010] Furthermore, the liquid material forms a high Reynolds number vortex in the vortex mixing chamber and is fully mixed with the supersonic steam, and the supersonic steam jet entrains the liquid material to form a gas-liquid mixture.

[0011] Furthermore, the gas-liquid mixture enters the collimated jet section of the jet module and continues to enter the shock wave expansion section; the gas-liquid mixture forms a shock wave in the shock wave expansion section, further promoting mixing, heat transfer and phase change processes.

[0012] Furthermore, the gas-liquid mixture fully transfers heat and changes phase in the relative mixing zone, gradually transforming into a liquid phase while slowing down; the relative mixing zone is connected to the material outlet.

[0013] Furthermore, the diameter of the compression section is 50%-70% of the diameter of the steam inlet; the diameter of the steam jet nozzle is 30%-50% of the diameter of the compression section; the cone angle of the compression section is 14°-18°; and the cone angle of the shock wave expansion section is 9-14°.

[0014] Furthermore, when the temperature is raised to 145°C, the distance between the steam jet nozzle and the collimated jet section is larger than the diameter of the steam jet nozzle; the diameter of the collimated jet section is 11%-15% smaller than the diameter of the steam jet nozzle; the length of the collimated jet section is equal to the diameter; When the maximum temperature rises to 157°C, the distance between the steam jet nozzle and the collimated jet section is equal to the diameter of the steam jet nozzle; the diameter of the collimated jet section is equal to the diameter of the steam jet nozzle; and the length of the collimated jet section is smaller than its diameter.

[0015] Beneficial effects of the present invention: 1. The present invention aims at the temperature rising condition of ultra-high temperature instantaneous sterilization, and achieves better gas-liquid mixing effect; 2. The present invention can make the temperature of the mixed materials more uniform and achieve better sterilization effect; 3. The present invention has better temperature stability and better mixing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention has the following accompanying drawings: Figure 1 is a schematic diagram of the structure of a mixer according to Example 1 of the present invention; Figure 2 is a schematic diagram of the structure of a mixer according to Embodiment 5 of the present invention; Figure 3 1 is a schematic diagram comparing the effects of the mixer of Example 1 of the present invention and a traditional mixer; Figure 4 1 is a schematic diagram comparing the effects of the mixer of Example 5 of the present invention and a traditional mixer; Figure 5 is a comparison photo of the mixing effect of the mixer of Example 5 of the present invention and the conventional mixer; Among them, 1. Steam inlet module; 2. Nozzle main body module; 3. Jet module; 4. Outlet module; 5. Steam inlet; 6. Compression section; 7. Contraction acceleration section; 8. Steam jet nozzle; 9. Liquid material inlet; 10. Vortex mixing chamber; 11. Collimated jet section; 12. Shock wave expansion section; 13. Phase change mixing zone; 14. Material outlet. DETAILED DESCRIPTION

[0017] In order to make the objects, advantages and features of the present invention more obvious, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] like Figure 1 As shown, a steam direct injection mixer comprises: 1. a steam inlet module; 2. a nozzle main body module; 3. a jet module; 4. an outlet module; 5. a steam inlet; 6. a compression section; 7. a contraction acceleration section; 8. a steam jet nozzle; 9. a liquid material inlet; 10. a vortex mixing chamber; 11. a collimated jet section; 12. a shock wave expansion section; 13. a phase change mixing zone; 14. a material outlet; wherein the steam inlet module 1 and the outlet module 4 are respectively fastened to the nozzle main body module 2 by threads, and the jet module 3 is clamped and fixed when the outlet module 4 is fastened to the nozzle main body module 2 by threads. The space between the inlet module 1 and the jet module 3 forms a vortex mixing chamber 10, and the liquid material inlet 9 is connected to the vortex mixing chamber 10.

[0019] Steam enters the steam inlet module 1 from the steam inlet 5 and enters the compression section 6. Since the diameter of the compression section 6 is smaller than the steam inlet 5, the steam is compressed and accelerated in the compression section 6. Subsequently, the steam enters the contraction acceleration section 7 having a conical structure for acceleration, and is ejected through the steam jet nozzle 8 as a supersonic jet and passes through the vortex mixing chamber 10.

[0020] The liquid material enters the vortex mixing chamber 10 from the liquid material 9. Since there is a supersonic steam jet at the center of the vortex mixing chamber 10, the liquid material is driven to form a high Reynolds number vortex in the vortex mixing chamber 10 and is fully mixed with the supersonic steam. Subsequently, the supersonic steam jet entrains the liquid material to form a gas-liquid mixture and enters the collimated jet section 11 of the jet module 3, and continues to maintain a high-speed state, and enters the shock wave expansion section 12. The gas-liquid mixture forms a shock wave in the shock wave expansion section 12, which further promotes the mixing, heat transfer and phase change processes. Next, the gas-liquid mixture achieves sufficient heat transfer and phase change in the phase change mixing zone 13, and gradually changes to a liquid-dominated phase, while achieving deceleration.

[0021] Relative size: 1) The diameter of the compression section 6 is 50%-70% of the diameter of the steam inlet 5, preferably about 60%; 2) The diameter of the steam jet nozzle 8 is 30%-50% of the diameter of the compression section 6, preferably about 40%; the cone angle of the compression section 6 is 14°-18°, preferably 16°; The first group of designs, for the working condition with the highest temperature rising to 145℃, the rear section adopts the following design: 3) The distance between the steam jet nozzle 8 and the collimated jet section 11 is larger than the diameter of the steam jet nozzle 8; 4) The diameter of the collimated jet section 11 is 11%-15% smaller than the diameter of the steam jet nozzle 8; 5) The length and diameter of the collimated jet section 11 are equal; 6) The cone angle of the shock wave expansion section 12 is 9-14°; Specific embodiment 1:

[0022] 1) The diameter of the steam inlet 5 is 30 mm; the diameter of the compression section 6 is 17 mm 2) The diameter of the steam jet nozzle 8 is 7 mm; the cone angle of the compression section 6 is 16°; 3) The distance between the steam jet nozzle 8 and the collimated jet section 11 is 10 mm 4) The diameter of the collimated jet section 11 is 6 mm; 5) The length of the collimated jet section 11 is 6 mm; 6) The length of the shock wave expansion section 12 is 12 mm; the cone angle is 10° Specific embodiment 2:

[0023] 1) The diameter of the steam inlet 5 is 30 mm; the diameter of the compression section 6 is 17 mm 2) The diameter of the steam jet nozzle 8 is 8 mm; the cone angle of the compression section 6 is 16°; 3) The distance between the steam jet nozzle 8 and the collimated jet section 11 is 9 mm 4) The diameter of the collimated jet section 11 is 7 mm; 5) The length of the collimated jet section 11 is 7 mm; 6) The length of the shock wave expansion section 12 is 13 mm; the cone angle is 9° Specific embodiment 3:

[0024] 1) The diameter of the steam inlet 5 is 30 mm; the diameter of the compression section 6 is 17 mm 2) The diameter of the steam jet nozzle 8 is 8 mm; the cone angle of the compression section 6 is 16°; 3) The distance between the steam jet nozzle 8 and the collimated jet section 11 is 9 mm 4) The diameter of the collimated jet section 11 is 7 mm; 5) The length of the collimated jet section 11 is 7 mm; 6) The length of the shock wave expansion section 12 is 38 mm; the cone angle is 12° The second group of designs, for the working condition with the highest temperature rising to 157℃, the rear section adopts the following design: 3) The distance between the steam jet nozzle 8 and the collimated jet section 11 is equal to the diameter of the steam jet nozzle 8; 4) The diameter of the collimated jet section 11 is equal to the diameter of the steam jet nozzle 8; 5) The length of the collimated jet section 11 is smaller than its diameter; 6) The cone angle of the shock wave expansion section 12 is 9-14°; Specific embodiment 4:

[0025] 7) The diameter of the steam inlet 5 is 30 mm; the diameter of the compression section 6 is 17 mm 8) The diameter of the steam jet nozzle 8 is 9 mm; the cone angle of the compression section 6 is 16°; 9) The distance between the steam jet nozzle 8 and the collimated jet section 11 is 9 mm 10) The diameter of the collimated jet section 11 is 9 mm; 11) The length of the collimated jet section 11 is 7 mm; 12) The length of the shock wave expansion section 12 is 13 mm; the cone angle is 9° like Figure 2 As shown, specific embodiment 5: 7) The diameter of the steam inlet 5 is 30 mm; the diameter of the compression section 6 is 17 mm 8) The diameter of the steam jet nozzle 8 is 9 mm; the cone angle of the compression section 6 is 16°; 9) The distance between the steam jet nozzle 8 and the collimated jet section 11 is 9 mm 10) The diameter of the collimated jet section 11 is 9 mm; 11) The length of the collimated jet section 11 is 7 mm; 12) The length of the shock wave expansion section 12 is 38 mm; the cone angle is 12° Figure 3 It is a comparison between the mixer of Example 1 of the present invention and the traditional mixer, and the temperature fluctuation of the material within 1 hour after mixing and heating. The mixer adopts the size in the specific embodiment 1. The material is milk, and the sterilization temperature is set to 135°C. It can be seen that the temperature fluctuation of the mixer of Example 1 of the present invention is 134.8-135.4°C, while the temperature fluctuation of the traditional mixer is 134.3-135.9°C. Compared with the traditional steam mixer, the present invention can achieve a better mixing effect of steam and liquid, the temperature of the mixed material is more uniform, and a better sterilization effect can be achieved.

[0026] Figure 4It is a comparison between the mixer of Example 5 of the present invention and the traditional mixer, and the temperature fluctuation of the material within 1 hour after mixing and heating. The mixer adopts the size in the specific embodiment 5. The material is milk, and the sterilization temperature is set to 157°C. It can be seen that the temperature fluctuation of the mixer of Example 5 of the present invention is 156.6-157.5°C, while the temperature fluctuation of the traditional mixer is 156.1-159.0°C. Compared with the traditional steam mixer, the present invention can achieve a better mixing effect of steam and liquid, the temperature of the mixed material is more uniform, and a better sterilization effect can be achieved.

[0027] Figure 5 This is a comparison of the mixing effect of the mixer of Example 5 and the traditional mixer. The window installed after the mixer is used to observe the mixing effect of the material and the steam after passing through the mixer. Through the window, it can be seen that after the material passes through the steam mixer of Example 5 of the present invention, it is very uniform and there are no obvious bubbles. After passing through the traditional steam mixer, the material is filled with a large number of bubbles. This is why Example 5 has better temperature stability than the traditional mixer. This result shows that the mixer of the present invention has a better mixing effect.

[0028] The above embodiments describe the technical solutions of the present invention in detail. Obviously, the present invention is not limited to the described embodiments. Based on the embodiments of the present invention, people familiar with the technical field can also make various changes accordingly, but any changes that are equivalent or similar to the present invention belong to the scope of protection of the present invention.

[0029] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. An ultra-high temperature instantaneous sterilization steam direct injection mixer, characterized in that: It comprises a steam inlet module, a nozzle main body module, a jet module and an outlet module. The steam inlet module and the outlet module are respectively connected to the nozzle main body module; the jet module is clamped and fixed to the nozzle main body module through the outlet module.

2. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 1, characterized in that: The steam inlet module and the outlet module are respectively fastened to the nozzle main body module through threads, and the jet module is clamped and fixed when the outlet module and the nozzle main body module are fastened through threads.

3. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 2, characterized in that: The space between the steam inlet module and the jet module forms a vortex mixing chamber, and the liquid material inlet is communicated with the vortex mixing chamber.

4. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 3, characterized in that: The steam inlet module includes a steam inlet, a compression section, a contraction accelerator, and a steam jet nozzle. The diameter of the compression section is smaller than that of the steam inlet. The contraction accelerator is a conical structure for accelerating the steam after entering. Steam is ejected through the steam jet nozzle in the form of a supersonic jet and passes through the vortex mixing chamber.

5. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 4, characterized in that: A liquid material inlet is provided above the vortex mixing chamber, and is used for liquid material to enter the vortex mixing chamber from the liquid material inlet.

6. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 5, characterized in that: The liquid material forms a high Reynolds number vortex in the vortex mixing chamber and is fully mixed with the supersonic steam. The supersonic steam jet entrains the liquid material to form a gas-liquid mixture.

7. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 6, characterized in that: The gas-liquid mixture enters the collimated jet section of the jet module and continues to enter the shock wave expansion section; the gas-liquid mixture forms a shock wave in the shock wave expansion section, further promoting mixing, heat transfer and phase change processes.

8. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 7, characterized in that: The gas-liquid mixture fully transfers heat and changes phase in the relative mixing zone, gradually transforming into a liquid phase while slowing down; the relative mixing zone is connected to the material outlet.

9. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 8, characterized in that: The diameter of the compression section is 50%-70% of the diameter of the steam inlet; the diameter of the steam jet nozzle is 30%-50% of the diameter of the compression section; the cone angle of the compression section is 14°-18°; the cone angle of the shock wave expansion section is 9-14°.

10. The ultra-high temperature instantaneous sterilization steam direct injection mixer according to claim 9, characterized in that: When the temperature is raised to 145°C, the distance between the steam jet nozzle and the collimated jet section is larger than the diameter of the steam jet nozzle; the diameter of the collimated jet section is 11%-15% smaller than the diameter of the steam jet nozzle; the length of the collimated jet section is equal to the diameter; When the maximum temperature rises to 157°C, the distance between the steam jet nozzle and the collimated jet section is equal to the diameter of the steam jet nozzle; the diameter of the collimated jet section is equal to the diameter of the steam jet nozzle; and the length of the collimated jet section is smaller than its diameter.

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