Atomizer and method for preparing vitamin microcapsules

Abstract

The application relates to an atomizer and a preparation method of vitamin microcapsules. The atomizer comprises a base and a nozzle assembly arranged at one end of the base. The nozzle assembly comprises a shell, a core and a flow limiting piece. A first cavity is arranged in the base, a second cavity is arranged in the shell, the shell is connected to one end of the base, the second cavity is communicated with the first cavity, the core is arranged in the second cavity and connected with the shell, a flow guide hole and an atomizing hole which are communicated with each other are arranged in the core, the flow guide hole is in an inverted conical shape, the atomizing hole is located at one end of the flow guide hole with a smaller inner diameter, a plurality of atomizing grooves which are radially distributed are arranged on the side wall of the flow guide hole, one end of the atomizing grooves is communicated with the connection position of the atomizing hole and the flow guide hole, and the other end extends towards the upper end of the flow guide hole. The flow limiting piece is arranged at least partially in the flow guide hole to block the emulsion, so that the emulsion flows from the atomizing grooves to the atomizing hole. The atomizer provided by the application improves the rotating speed of the emulsion, and makes the particle size of the emulsion particles sprayed from the atomizing hole more uniform.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nutritional product production, in particular to an atomizer and a preparation method of vitamin microcapsules. BACKGROUND

[0002] Most vitamin varieties are unstable and prone to deterioration under the action of oxygen, moisture, light and heat. Vitamin microcapsules can be prepared by microcapsule technology to improve the bioavailability of vitamins in practical applications.

[0003] In the prior art, vitamin microcapsules are generally prepared by the following method: 1. dissolving or melting the vitamin; 2. adding the dissolved or melted vitamin into a water phase in which an embedding material is dissolved, and homogenizing the vitamin emulsion by high-speed shearing and a homogenizer; and 3. obtaining two different particle size specifications of microcapsules by spray drying or spray granulation.

[0004] When the spray drying method is used to prepare vitamin microcapsules, the vitamin emulsion is generally pressurized by a high-pressure spray pump and then sent into a spray drying tower for spray drying. The emulsion is atomized by the atomizing nozzle of the spray drying tower, and the atomized emulsion exchanges moisture and heat with the high-temperature gas flow to obtain microcapsules with very low water content, and the moisture in the emulsion is carried out of the spray drying tower by the hot air.

[0005] In the prior art, when the spray drying method is used to prepare vitamin microcapsules, in order to enable the atomizer to spray emulsion with more uniform particle size distribution, the solid content of the vitamin emulsion is generally controlled at 30% to 45%, and the corresponding water content is 55% to 70%. When the water content of the microcapsule product is less than 5%, the thermal efficiency of the spray drying tower is generally 35% to 45%, which is relatively low and has high energy consumption.

[0006] In order to reduce the energy consumption of the spray drying tower during the spray drying process, the simplest method is to increase the solid content of the emulsion and reduce the water content of the emulsion. However, the higher the solid content, the greater the viscosity of the emulsion, and the worse the uniformity of the droplet particle size sprayed. Therefore, how to improve the uniformity of the droplet particle size sprayed by the emulsion is a technical problem to be solved. SUMMARY

[0007] Therefore, it is necessary to provide an atomizer and a preparation method of vitamin microcapsules, which can improve the uniformity of the droplet particle size of the atomized liquid.

[0008] The application provides an atomizer, which comprises a base and a nozzle assembly arranged at one end of the base, wherein the nozzle assembly comprises a shell, a core and a flow limiting piece, the base is internally provided with a first cavity, the shell is internally provided with a second cavity, the shell is connected to one end of the base, the second cavity is communicated with the first cavity, the core is arranged in the second cavity and connected to the shell, the core is internally provided with a flow guide hole and an atomizing hole which are communicated with each other, the flow guide hole is in an inverted conical shape, the atomizing hole is located at one end of the flow guide hole with a smaller inner diameter, the side wall of the flow guide hole is provided with a plurality of atomizing grooves which are distributed in a radial manner, one end of the atomizing grooves is communicated with the connection position of the atomizing hole and the flow guide hole, and the other end extends towards the upper end of the flow guide hole, and the flow limiting piece is arranged at least partially in the flow guide hole to block the emulsion so that the emulsion flows from the atomizing grooves to the atomizing hole.

[0009] In one of the embodiments, one end of the intersection of the plurality of atomizing grooves forms an annular converging groove which surrounds the atomizing hole, and a converging step is formed between the converging groove and the atomizing hole.

[0010] In one of the embodiments, the extension line of the atomizing groove is tangent to the atomizing hole in the projection direction of the center line of the atomizing hole.

[0011] In one of the embodiments, the flow limiting piece is arranged as a sphere, the outer wall of the flow limiting piece is tangent to the side wall of the flow guide hole, and a vortex area is formed below the tangent position.

[0012] In one of the embodiments, the diameter of the flow limiting piece is 3mm-8mm.

[0013] In one of the embodiments, the nozzle assembly further comprises a flow dividing piece which is arranged between the first cavity and the second cavity, the flow dividing piece comprises a baffle part which separates the first cavity and the second cavity, the baffle part is provided with a flow dividing hole which communicates the first cavity and the second cavity.

[0014] In one of the embodiments, the flow dividing piece further comprises a rod part which is connected to the baffle part at one end and abuts against the flow limiting piece at the other end, so that the flow limiting piece is tightly attached to the inner wall of the flow guide hole.

[0015] In one of the embodiments, the inner wall of the base is provided with an annular limiting boss, one end of the shell extends into the first cavity and is threadedly connected to the base, and the baffle part is clamped between the limiting boss and the shell.

[0016] In one of the embodiments, the taper angle of the flow guide hole is 60°-120°, and / or the hole diameter of the atomizing hole is 0.5mm-1.5mm.

[0017] This application also provides a method for preparing vitamin microcapsules, which uses an atomizer as described above, including: a vitamin emulsion is pressurized by a high-pressure spray pump and enters the first chamber of the atomizer, and finally sprays out from the atomizing hole to form a spray, and the spray exchanges heat with the hot airflow to obtain vitamin microcapsules.

[0018] Compared to existing technologies, the atomizer provided in this application, by incorporating a flow-limiting element, prevents the emulsion from flowing directly along the sidewall of the guide hole to the atomizing hole. Instead, it flows through atomizing grooves to the atomizing hole, increasing the emulsion's flow resistance and thus mitigating the adverse effects of high-pressure spray pump pressure fluctuations on the emulsion particle size distribution. Because the guide hole is inverted conical in shape, and its sidewall has multiple radially distributed atomizing grooves, these grooves accelerate the rotation of the emulsion, increasing its rotational speed and resulting in more uniform emulsion particle size ejected from the atomizing hole. Therefore, this atomizer can be used for atomizing high-solids-content emulsions, ensuring good particle size uniformity. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of an atomizer according to an embodiment of this application;

[0021] Figure 2 for Figure 1 Top view;

[0022] Figure 3 for Figure 2 Sectional view along line AA;

[0023] Figure 4 for Figure 1 A bottom view;

[0024] Figure 5 This is a schematic diagram of the core structure according to an embodiment of this application;

[0025] Figure 6 for Figure 5 Top view;

[0026] Figure 7 for Figure 5 A sectional view;

[0027] Figure 8 This is a schematic diagram of the structure of a conventional atomizer.

[0028] 10, base; 11, first cavity; 12, limiting boss; 13, first platform; 14, internal thread; 20, nozzle assembly; 30, shell; 31, second cavity; 32, annular protrusion; 321, second platform; 40, core; 41, flow guide hole; 411, vortex area; 42, atomizing hole; 43, atomizing groove; 44, flow converging groove; 50, flow limiting member; 60, flow dividing member; 61, baffle part; 611, flow dividing hole; 62, rod part; 621, limiting groove; 101, vortex chamber; 102, nozzle hole. DETAILED DESCRIPTION

[0029] In order to make the above objectives, features and advantages of the present application more clear and easily understood, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of different ways from those described herein without departing from the scope of the present application, and it is understood that similar improvements can be made by those skilled in the art without departing from the spirit of the present application, and therefore the present application is not limited to the specific embodiments disclosed below.

[0030] It should be noted that when an element is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element, or intervening elements can also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element, or intervening elements can also be present. The terms "vertical", "horizontal", "upper", "lower", "left", "right", and similar expressions as used in the description of the specification are for the purpose of illustration only and do not indicate the only position of the embodiment.

[0031] In addition, the terms "first", "second", etc. are used herein only to describe various elements, and are not used to indicate or imply relative importance or a number of indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0032] In the present application, unless otherwise explicitly specified and limited, the "on", "under", "above" and "over" of the first feature to the second feature can be that the first feature is directly in contact with the second feature, or the first feature is indirectly in contact with the second feature through an intermediate medium. Moreover, the "on", "above" and "over" of the first feature to the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "under", "below" and "under" of the first feature to the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0033] Unless otherwise defined, all technical and scientific terms used in the application's specification are intended to have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the application's specification is for describing particular embodiments only and is not intended to be limiting. The use of the terms "and / or" includes a combination of one or more of the associated listed items.

[0034] Please refer to Figures 1 to 4 The application provides an atomizer, comprising a base 10 and a nozzle assembly 20 arranged at one end of the base 10, the nozzle assembly 20 comprising a shell 30, a core 40 and a flow limiting piece 50. The base 10 is provided with a first cavity 11, and the shell 30 is provided with a second cavity 31, the shell 30 being connected to one end of the base 10, and the second cavity 31 being in communication with the first cavity 11. The core 40 is arranged in the second cavity 31, and the core 40 is connected to the shell 30. The core 40 is provided with a flow guide hole 41 and an atomizing hole 42 in communication. The flow guide hole 41 is inverted conical, with a larger inner diameter at one end and a smaller inner diameter at the other end. The atomizing hole 42 is located at the end of the flow guide hole 41 with the smaller inner diameter, and the atomizing hole 42 is in communication with the flow guide hole 41. The side wall of the flow guide hole 41 is provided with a plurality of atomizing grooves 43 distributed radially, one end of the plurality of atomizing grooves 43 being in communication with the connection between the atomizing hole 42 and the flow guide hole 41, and the other end extending towards the upper end of the flow guide hole 41. The flow limiting piece 50 is at least partially arranged in the flow guide hole 41 to block the emulsion, so that the emulsion flows from the atomizing grooves 43 to the atomizing hole 42. The atomizer provided by the application sets the flow limiting piece 50, so that the emulsion cannot directly flow along the side wall of the flow guide hole 41 to the atomizing hole 42, but flows through the atomizing grooves 43 to the atomizing hole 42, increasing the flow resistance of the emulsion, thereby weakening the adverse effects of pressure fluctuations of the high-pressure spray pump on the particle size distribution of the emulsion. Since the flow guide hole 41 is inverted conical, and the side wall of the flow guide hole 41 is provided with a plurality of atomizing grooves 43 distributed radially, the atomizing grooves 43 accelerate the rotation of the emulsion, increasing the rotation speed of the emulsion, so that the emulsion particles sprayed from the atomizing hole 42 are more uniform in size. In this way, the atomizer can be used for atomizing high-solid-content emulsion, and can ensure good particle size uniformity.

[0035] Further, please refer to Figures 5 to 7 One end of the plurality of atomizing grooves 43 converges to form an annular converging groove 44, the converging groove 44 surrounding the atomizing hole 42, and a converging step being formed between the converging groove 44 and the atomizing hole 42. In this way, the emulsion first concentrates in the converging groove 44 after passing through the atomizing grooves 43, and then flows from the converging groove 44 to the atomizing hole 42, which is conducive to forming a vortex in the converging groove 44 and increasing the rotation speed of the emulsion. The centrifugal force of the rotating emulsion causes further breakup of the droplets, resulting in better uniformity of the emulsion particles sprayed from the atomizing hole 42, so that the atomizer can adapt to the atomization of emulsion with high solid content.

[0036] Please refer to Figure 6 , the projection of the atomizing hole 42 along the center line direction of the atomizing hole 42, the extension line of the atomizing groove 43 is tangent to the atomizing hole 42. In this way, after the emulsion passes through the atomizing groove 43, it enters the flow collection groove 44 along the tangent direction of the atomizing hole 42, and forms a vortex below the flow limiting part 50. The extension line of the atomizing groove 43 is tangent to the atomizing hole 42, which not only promotes the rotation of the emulsion sprayed from the atomizing hole 42 into the spray drying tower, but also accelerates the rotation of the emulsion in the area below the flow limiting part 50. The double speed-up effect makes the spraying distance of the emulsion sprayed from the atomizing hole 42 shorter, and the emulsion has a smaller particle size.

[0037] The atomizing grooves 43 are uniformly arranged along the circumference of the atomizing hole 42, and further, the number of the atomizing grooves 43 can be 4 to 8. As shown in Figure 5 and Figure 6 , the number of the atomizing grooves 43 is 6.

[0038] Please refer to Figure 3 , in this embodiment, the flow limiting part 50 is a sphere, the outer wall of the flow limiting part 50 is tangent to the side wall of the flow guide hole 41, and a vortex area 411 is formed below the tangent position. In this way, the flow limiting part 50 has a very simple structure, which can well separate the second cavity 31 into upper and lower two areas, and make the emulsion in the upper area of the second cavity 31 flow to the vortex area 411 after passing through the atomizing groove 43, and form a vortex in the vortex area 411.

[0039] Further, the diameter of the flow limiting part 50 is 3mm to 8mm. In the case where the taper angle of the flow guide hole 41 is determined, the larger the diameter of the flow limiting part 50, the larger the vortex area 411, the larger the spraying distance of the emulsion, and the smaller the rotational speed, then the particle size of the emulsion sprayed from the atomizing hole 42 becomes larger; the smaller the diameter of the flow limiting part 50, the smaller the vortex area 411, the smaller the spraying distance of the emulsion, and the larger the rotational speed, then the particle size of the emulsion sprayed from the atomizing hole 42 becomes smaller. In this embodiment, the diameter of the flow limiting part 50 is set to 3mm to 8mm, which can make the particle size distribution of the emulsion sprayed from the atomizing hole 42 more uniform. In some specific embodiments, the diameter of the flow limiting part 50 can be 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, or any other value within the range of 3mm to 8mm.

[0040] In this embodiment, the flow limiting part 50 is detachably arranged in the flow guide hole 41. In this way, it is convenient to replace the flow limiting part 50, and different particle sizes of emulsion particles can be obtained by replacing flow limiting parts 50 of different sizes.

[0041] Further, the taper angle of the flow guide hole 41 is 60°-120°. The size of the taper angle of the flow guide hole 41 determines the cross-sectional shape of the vortex area 411. When the taper angle is larger, the vortex area 411 is flat, the rotating speed of the emulsion is faster, the distance of the emulsion sprayed from the atomizing hole 42 is shorter, and the particle size of the sprayed emulsion is smaller; when the taper angle is smaller, the vortex area 411 becomes long and thin, the rotating speed of the emulsion is slower, the distance of the emulsion sprayed from the atomizing hole 42 is longer, and the particle size of the sprayed emulsion is larger. In this application, the taper angle of the flow guide hole 41 is set to 60°-120°, so that the emulsion particles with moderate particle size can be obtained. In some specific embodiments, the taper angle of the flow guide hole 41 can be set to 60°, 70°, 80°, 90°, 100°, 110°, 120°, or any other value within the range of 60°-120°.

[0042] Further, the diameter of the atomizing hole 42 is 0.5mm-1.5mm, so that the requirements of most vitamin products for spray drying can be met. In some specific embodiments, the diameter of the atomizing hole 42 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, or any other value within the range of 0.5mm-1.5mm.

[0043] Please refer to Figure 3 Further, the nozzle assembly 20 further comprises a flow dividing member 60 arranged between the first cavity 11 and the second cavity 31. The flow dividing member 60 comprises a baffle part 61 separating the first cavity 11 and the second cavity 31, and the baffle part 61 is provided with a flow dividing hole 611 communicating the first cavity 11 and the second cavity 31. In this way, the emulsion in the first cavity 11 is divided by the flow dividing hole 611 before entering the second cavity 31, and the flow dividing member 60 can further increase the flow resistance of the emulsion, thereby facilitating the formation of a spray with more uniform particle size distribution.

[0044] Further, the flow dividing member 60 further comprises a rod part 62 connected to the baffle part 61 at one end and abutting against the flow limiting member 50 at the other end, so that the flow limiting member 50 is tightly attached to the inner wall of the flow guide hole 41. In this way, the flow dividing member 60 not only plays a role in dividing the flow, but also plays a role in fixing the flow limiting member 50, so that the flow limiting member 50 can prevent the emulsion from flowing directly along the side wall of the flow guide hole 41.

[0045] In this embodiment, the flow dividing hole 611 is arranged on the outer circumferential side of the rod part 62 and uniformly arranged in the circumferential direction, so that the emulsion in the first cavity 11 can flow uniformly to the second cavity 31 through the flow dividing hole 611.

[0046] The lower end of the rod part 62 is provided with a tapered limiting slot 621, so that the limiting slot 621 can wrap the one end of the flow limiting piece 50, thereby facilitating the fixation of the flow limiting piece 50. It can be understood that, for different sizes of the flow limiting piece 50, the flow limiting piece 50 is fixed by replacing the flow dividing piece 60 with different lengths.

[0047] Further, referring to Figure 2 and Figure 3 , the inner wall of the base 10 is provided with an annular limiting boss 12, one end of the shell 30 extends into the first cavity 11 and is threadedly connected with the base 10, and the baffle part 61 is clamped between the limiting boss 12 and the shell 30. In this way, the shell 30 and the base 10 are easily connected, and the installation and replacement of the flow dividing piece 60 and the flow limiting piece 50 are facilitated. During installation, the core 40, the flow limiting piece 50 and the flow dividing piece 60 are sequentially installed in the second cavity 31 of the shell 30, and then one end of the shell 30 is threadedly connected with the base 10, so that the nozzle assembly 20 can be installed on the base 10. The entire installation process is very simple and easy to operate.

[0048] Further, referring to Figure 3 , the end of the base 10 away from the shell 30 is provided with an internal thread 14, so that the base 10 is facilitated to be connected with the pipeline of the high-pressure spray pump.

[0049] Further, referring to Figure 1 and Figure 2 , in order to facilitate the rotation of the base 10, the opposite sides of the outer surface of the base 10 are provided with first platforms 13. When the base 10 is rotated by using a wrench, the wrench can be clamped at the first platforms 13, so that the slippage of the wrench is avoided, thereby facilitating the rotation of the base 10.

[0050] Further, referring to Figure 3 and Figure 4 , the outer surface of the shell 30 is provided with an annular protrusion 32, and the opposite sides of the annular protrusion 32 are provided with second platforms 321. When the nozzle assembly 20 is installed or disassembled by using a wrench, the wrench can be clamped at the second platforms 321, so that the slippage of the wrench is avoided, thereby facilitating the rotation of the shell 30.

[0051] In the prior art, when preparing vitamin microcapsules by using the spray drying method, in order to ensure that the atomizer can spray smaller particles, the solid content of the vitamin emulsion is usually controlled to be 30% to 45%, and the corresponding water content is 55% to 70%. When the water content of the vitamin microcapsule product is controlled to be less than 5%, the thermal efficiency of the spray drying tower is about 35% to 45%. However, by using the atomizer of the present application, the vitamin emulsion with a solid content of 45% to 55% can be atomized under the premise of ensuring the uniformity of the emulsion particles. When the water content of the vitamin microcapsule product is controlled to be less than 5%, the thermal efficiency of the spray tower can reach 45% to 55%, which greatly reduces the energy consumption of the spray drying tower, thereby reducing the production cost.

[0052] The present application also provides a preparation method of vitamin microcapsules, which is prepared by using the atomizer as described above. The preparation method of the vitamin microcapsules comprises: the vitamin emulsion is pressurized by a high-pressure spray pump and then enters the first cavity 11 of the atomizer, and finally forms a spray from the atomizing holes 42. The vitamin microcapsules are obtained after the spray exchanges heat with the hot gas flow. Due to the arrangement of the flow limiting member 50 and the atomizing groove 43, the emulsion flows to the atomizing holes 42 after passing through the atomizing groove 43. The arrangement of the flow limiting member 50 increases the flow resistance of the fluid, thereby weakening the adverse effects of the high-pressure spray pump on the particle size distribution of the emulsion, improving the atomization effect of the emulsion with high solid content or high viscosity, and making the particle size uniformity of the atomized particles better.

[0053] Further, the solid content of the vitamin emulsion is 45% to 55%. In this way, the solid content of the vitamin emulsion is higher, which is easier to dry, can reduce the drying energy consumption, and save the production cost.

[0054] It can be understood that the preparation of the vitamin emulsion can be obtained by using the prior art. In the following Example 1, the preparation of the vitamin emulsion is described in detail by taking the vitamin A palmitate emulsion as an example; and in Example 13, the preparation of the vitamin emulsion is described in detail by taking the vitamin E emulsion as an example. The preparation method of the vitamin microcapsules is described in detail as follows:

[0055] Example 1

[0056] The preparation process of the vitamin A palmitate emulsion is as follows:

[0057] (1) Preparation of oil phase:

[0058] Add the vitamin A palmitate in a molten state into the oil melting kettle: 50.0 kg, tocopherol: 1.5 kg, vegetable oil: 15.0 kg, BHT: 1.5 kg, heat to 55°C for melting, and after melting, prepare for use.

[0059] (2) Preparation of water phase:

[0060] Into the emulsification kettle, add 55℃ drinking water: 275kg, OSA starch sodium (Yireyan Hicap-100): 137.5kg, dextrin: 53.0kg, dissolve at 55℃.

[0061] (3) Emulsification: open the high-speed shearing device, add the vitamin A palmitate in the oil phase kettle into the emulsification kettle to carry out shearing emulsification, to obtain a coarse emulsion with emulsion particle size D(90) less than 10.0μm.

[0062] (4) High pressure homogenization: the coarse emulsion is homogenized by a high pressure homogenizer at 55MPa, to obtain a vitamin A palmitate emulsion with emulsion particle size D(90) less than 2.0μm and solid content of 48.45%.

[0063] Spray drying step: spray dry the vitamin A palmitate emulsion in a spray drying tower with upper inlet air and upper exhaust air and having a rotating flow field. Figures 1-7 The atomizer shown in the drawing is used, the atomizing hole diameter is selected to be 0.8mm, the flow guide hole cone angle is 90°, and the flow limiting member diameter is 5mm.

[0064] The vitamin A palmitate emulsion feed amount is controlled to be 270kg / h, the pressure is 16MPa, the temperature is 55℃, and the viscosity is 156CP. The inlet air temperature is 140℃, the inlet air amount is 5210NM 3 / h, and the outlet air temperature is 85℃.

[0065] The vitamin A palmitate microcapsule obtained has vitamin A palmitate content of 328,000IU / g, water content of 3.2%, particle size distribution of D(10)=17.1μm, D(50)=45.4μm, and D(90)=110.0μm. The spray tower heat efficiency is 48.36%.

[0066] Example 2

[0067] Example 2 is basically the same as Example 1, except that the flow limiting member diameter is 3mm. In order to ensure that the water content of the microcapsule product is below 5%, the inlet air amount is controlled to be 4910NM 3 / h. The vitamin A palmitate microcapsule obtained has content of 326,400IU / g, water content of 3.7%, particle size distribution of D(10)=14.1μm, D(50)=36.5μm, and D(90)=89.1μm. The spray tower heat efficiency is 51.10%.

[0068] Example 3

[0069] Example 3 is basically the same as Example 1, except that the flow limiting member diameter is 8mm. In order to ensure that the water content of the microcapsule product is below 5%, the inlet air amount is controlled to be 5370NM 3 / h. Vitamin A palmitate microcapsule content: 32.61 million IU / g, moisture content: 3.8%, particle size distribution: D(10) = 20.7 μm, D(50) = 54.3 μm, D(90) = 134.4 μm. Spray tower thermal efficiency: 46.72%.

[0070] Example 4

[0071] Example 4 is substantially the same as Example 1, except that the atomizing hole diameter is 0.5 mm. In order to ensure that the moisture content of the microcapsule product is below 5%, the air inlet amount is controlled to be 4810 NM 3 / h. Vitamin A palmitate microcapsule content: 32.58 million IU / g, moisture content: 3.9%, particle size distribution: D(10) = 13.4 μm, D(50) = 35.3 μm, D(90) = 86.7 μm. Spray tower thermal efficiency: 52.08%.

[0072] Example 5

[0073] Example 5 is substantially the same as Example 1, except that the atomizing hole diameter is 1.5 mm. In order to ensure that the moisture content of the microcapsule product is below 5%, the air inlet amount is controlled to be 5570 NM 3 / h. Vitamin A palmitate microcapsule content: 32.64 million IU / g, moisture content: 3.7%, particle size distribution: D(10) = 21.6 μm, D(50) = 58.2 μm, D(90) = 146.2 μm. Spray tower thermal efficiency: 45.06%.

[0074] Example 6

[0075] Example 6 is substantially the same as Example 1, except that the guide hole cone angle is 60°. In order to ensure that the moisture content of the microcapsule product is below 5%, the air inlet amount is controlled to be 5570 NM 3 / h. Vitamin A palmitate microcapsule content: 32.70 million IU / g, moisture content: 3.5%, particle size distribution: D(10) = 25.4 μm, D(50) = 65.9 μm, D(90) = 166.2 μm. Spray tower thermal efficiency: 45.15%.

[0076] Example 7

[0077] Example 7 is substantially the same as Example 1, except that the guide hole cone angle is 120°. In order to ensure that the moisture content of the microcapsule product is below 5%, the air inlet amount is controlled to be 4910 NM 3IU / g, water content: 3.3%, particle size distribution: D(10) = 11.6 μm, D(50) = 30.6 μm, D(90) = 73.5 μm. Spray tower thermal efficiency: 49.93%.

[0078] Example 8

[0079] Example 8 is substantially the same as Example 1, except that the amount of drinking water used in preparing the water phase is 316 kg, and a vitamin A palmitate emulsion having a solid content of 45% is obtained. In order to ensure that the water content of the microcapsule product is below 5%, the amount of air intake is controlled to be 5410 NM 3 IU / g, water content: 3.3%, particle size distribution: D(10) = 11.6 μm, D(50) = 30.6 μm, D(90) = 73.5 μm. Spray tower thermal efficiency: 49.93%.

[0080] Example 9

[0081] Example 9 is substantially the same as Example 1, except that the amount of drinking water used in preparing the water phase is 211 kg, and a vitamin A palmitate emulsion having a solid content of 55% is obtained. In order to ensure that the water content of the microcapsule product is below 5%, the amount of air intake is controlled to be 4310 NM 3 IU / g, water content: 3.4%, particle size distribution: D(10) = 26.3 μm, D(50) = 69.9 μm, D(90) = 169.2 μm. Spray tower thermal efficiency: 50.35%.

[0082] Example 10

[0083] Example 10 is substantially the same as Example 1, except that the atomizing hole diameter is 1.8 mm. In order to ensure that the water content of the microcapsule product is below 5%, the amount of air intake is controlled to be 5970 NM 3 IU / g, water content: 3.5%, particle size distribution: D(10) = 27.4 μm, D(50) = 73.0 μm, D(90) = 188.0 μm. Spray tower thermal efficiency: 42.09%.

[0084] Example 11

[0085] Example 11 is substantially the same as Example 1, except that the flow guide hole cone angle is 45°. In order to ensure that the water content of the microcapsule product is below 5%, the amount of air intake is controlled to be 6070 NM 3IU / g, moisture content: 3.7%, particle size distribution: D(10) = 24.5 μm, D(50) = 64.8 μm, D(90) = 157.5 μm. Spray tower thermal efficiency: 43.48%.

[0086] Example 12

[0087] Example 12 is substantially the same as Example 1, except that the flow restrictor diameter is 10 mm. In order to ensure that the moisture content of the microcapsule product is below 5%, the air inlet flow is controlled to be: 5770 NM 3 IU / g, moisture content: 3.7%, particle size distribution: D(10) = 24.5 μm, D(50) = 64.8 μm, D(90) = 157.5 μm. Spray tower thermal efficiency: 43.48%.

[0088] Example 13

[0089] (1) Oil phase preparation:

[0090] Into the oil melting kettle, add 55°C vitamin E acetate: 205.0 kg (content: 98.7%). Keep warm, ready for use.

[0091] (2) Water phase preparation:

[0092] Into the emulsification kettle, add 55°C drinking water: 320 kg, OSA starch sodium (Yiruan Hicap-100): 137.5 kg, dextrin: 53.0 kg, and dissolve at 55°C.

[0093] (3) Emulsification: open the high-speed shearing device, add the vitamin E acetate in the oil phase kettle into the emulsification kettle for shearing emulsification, to obtain a coarse emulsion with an emulsion particle size D(90) less than 10.0 μm.

[0094] (4) High pressure homogenization: the coarse emulsion is homogenized by a high pressure homogenizer at 55 MPa, to obtain a vitamin E acetate emulsion with an emulsion particle size D(90) less than 2.0 μm and a solid content of 55%.

[0095] Spray drying step: the vitamin E emulsion is spray dried in the spray drying tower described in Example 1. Control the vitamin E emulsion feed amount: 270 kg / h, pressure: 16 MPa, temperature: 55°C, viscosity: 164 CP. Air inlet temperature: 140°C, air inlet flow: 4410 NM 3 / h, air outlet temperature: 85°C.

[0096] Vitamin E acetate microcapsules were obtained: Vitamin E acetate content: 50.37%, water content: 2.9%, particle size distribution: D(10) = 25.3 μm, D(50) = 62.2 μm, D(90) = 159.8 μm. The thermal efficiency of the spray tower was 49.67%.

[0097] Comparative Example 1

[0098] Comparative Example 1 is basically the same as Example 1, except that: an existing atomizing nozzle is used to atomize the vitamin A palmitate emulsion with a solid content of 48.45%, and the air intake is controlled at 6680 NM. 3 / h. For example... Figure 8 As shown, existing atomizers do not have atomizing grooves or flow restrictors compared to the atomizer of this application. After the emulsion flows into the vortex chamber 101, it flows directly along the inner wall of the vortex chamber 101 to the nozzle hole 102 and is sprayed out from the nozzle hole 102. The obtained vitamin A palmitate microcapsules have a content of 326,700 IU / g, a water content of 3.6%, and a particle size distribution of D(10) = 14.9 μm, D(50) = 80.1 μm, and D(90) = 220.7 μm. The thermal efficiency of the spray tower is 37.59%.

[0099] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0100] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. An atomizer, characterized in that, include: A base and a nozzle assembly disposed at one end of the base, the nozzle assembly including a housing, a core, and a flow restrictor. The base has a first cavity, and the outer shell has a second cavity. The outer shell is connected to one end of the base, and the second cavity communicates with the first cavity. The core is disposed within the second cavity and is connected to the outer shell. The core contains interconnected guide holes and atomizing holes. The guide holes are inverted conical in shape, and the atomizing holes are located at the end with the smaller inner diameter of the guide holes. The sidewalls of the guide holes have multiple radially distributed atomizing grooves. The confluence of these grooves forms an annular converging groove that surrounds the atomizing holes, and a converging step is formed between the converging groove and the atomizing holes. The flow restrictor is at least partially disposed within the flow guide hole to block the vitamin emulsion, so that the vitamin emulsion flows from the atomizing groove to the atomizing hole. The flow restrictor is configured as a sphere, and the outer wall of the flow restrictor is tangent to the side wall of the flow guide hole, forming a vortex zone below the tangent point.

2. The atomizer according to claim 1, characterized in that, The projection along the center line of the atomizing hole shows that the extension line of the atomizing groove is tangent to the atomizing hole.

3. The atomizer according to claim 1, characterized in that, The diameter of the current limiting component is 3mm to 8mm.

4. The atomizer according to claim 1, characterized in that, The nozzle assembly further includes a flow divider disposed between the first cavity and the second cavity. The flow divider includes a baffle portion that separates the first cavity and the second cavity. The baffle portion has a flow divider hole that connects the first cavity and the second cavity.

5. The atomizer according to claim 4, characterized in that, The diverting component also includes a rod, one end of which is connected to the baffle and the other end of which abuts against the flow limiting component, so that the flow limiting component is in close contact with the inner wall of the guide hole.

6. The atomizer according to claim 4, characterized in that, The inner wall of the base is provided with an annular limiting boss. One end of the outer shell extends into the first cavity and is threadedly connected to the base. The baffle is clamped between the limiting boss and the outer shell.

7. The atomizer according to any one of claims 1-6, characterized in that, The cone angle of the guide hole is 60°~120°; And / or, the aperture of the atomizing hole is 0.5mm~1.5mm.

8. A method for preparing vitamin microcapsules, characterized in that, The preparation is carried out using the atomizer as described in any one of claims 1-7, comprising: a vitamin emulsion being pressurized by a high-pressure spray pump and then entering the first chamber of the atomizer, and finally being sprayed out from the atomizing hole to form a spray, and the spray exchanging heat with the hot airflow to obtain vitamin microcapsules.

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