Spray drying secondary agglomeration device

Abstract

The utility model discloses a spray drying secondary agglomeration device which comprises a spray drying tower, an air inlet device, a pressure spray gun, an air exhaust device, a cyclone separator, a fluidized bed, a first fine powder particle conveying pipe and a second fine powder particle conveying pipe, the spray drying tower is provided with a cavity, and the air inlet device and the pressure spray gun are arranged at the top of the spray drying tower; the top of the spray drying tower is communicated with the cyclone separator through an exhaust device; the spray drying tower is communicated with the fluidized bed; the feeding end of the first fine powder particle conveying pipe is communicated with the cyclone separator, the feeding end of the second fine powder particle conveying pipe is communicated with the fluidized bed, and the discharging end of the first fine powder particle conveying pipe and the discharging end of the second fine powder particle conveying pipe are both communicated with the middle position of the spray drying tower cavity. According to the spray drying secondary agglomeration device, secondary agglomeration can be carried out on fine powder particles which do not meet requirements and microcapsule particles in atomized feed liquid, and the situation that microcapsule powder cracks or discolors due to long-time drying of the fine powder particles is avoided.

Description

Technical Field

[0001] This utility model relates to the field of spray drying equipment, and in particular to a spray drying secondary agglomeration device. Background Technology

[0002] The spray-drying method for preparing microcapsules involves homogenizing a fine core material into a stable emulsion and dispersing it in a solution of the encapsulating material to form an emulsion dispersion, ensuring a uniform particle size distribution. This emulsion dispersion is then atomized into fine droplets using an atomizing device in a dry, hot air stream. Finally, it is spray-dried in a spray drying tower to obtain the microcapsule particles. The advantages of spray-dried microcapsules include long shelf life, high solubility, good dispersibility, and low cost. However, it also has the disadvantage of uneven particle size distribution. To achieve a certain uniform particle size, [further steps are needed]. Figure 3 As shown, fine powder particles that do not meet the requirements are often drawn from the cyclone separator 01 and fluidized bed 02 through the pipe 03 to the vicinity of the spray gun at the top of the spray drying tower 04, so that the fine powder particles re-enter the tower and combine with the atomized liquid for secondary agglomeration, thereby increasing the particle size. However, since the fine powder particles have lost moisture, after secondary agglomeration, the particles still need to fall slowly from the top of the tower again. During this process, the particles will be dried at high temperature again. Due to the particles being in contact with high temperature and dry air for a long time, over-drying is likely to occur, causing the microcapsule particles to crack or undergo severe Maillard reaction, resulting in browning and darkening of the color. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a spray drying secondary agglomeration device, which can perform secondary agglomeration of unqualified fine powder particles and microcapsule particles in atomized liquid, and the fine powder particles will not cause the microcapsule powder to crack or change color due to long-term drying.

[0004] To solve the above technical problems, the following technical solution is adopted:

[0005] A spray drying secondary agglomeration device includes a spray drying tower, an air inlet device, a pressure spray gun, an exhaust device, a cyclone separator, and a fluidized bed. The spray drying tower has a cavity, and the air inlet device and the pressure spray gun are located at the top of the cavity. The top of the cavity of the spray drying tower is connected to the gas inlet of the cyclone separator through the exhaust device. The bottom of the cavity of the spray drying tower is connected to the feed inlet of the fluidized bed. The device is characterized by further including a first fine powder particle conveying pipe and a second fine powder particle conveying pipe. The cyclone separator and the fluidized bed are respectively provided with fine powder particle outlets. The feed end of the first fine powder particle conveying pipe is connected to the fine powder particle outlet of the cyclone separator, and the feed end of the second fine powder particle conveying pipe is connected to the fine powder particle outlet of the fluidized bed. The discharge ends of both the first and second fine powder particle conveying pipes are connected to the middle position of the cavity of the spray drying tower.

[0006] When the aforementioned spray drying secondary agglomeration device is in operation, the spray drying tower sprays the atomized liquid to obtain microcapsule particles, which are then fed into a fluidized bed for further drying. During this drying process, air and fine powder particles at the top of the spray drying tower cavity are sent to a cyclone separator through an exhaust device. After separation by the cyclone separator, the fine powder particles are re-sprayed into the middle position of the spray drying tower cavity through the first fine powder particle conveying pipe. Similarly, fine powder particles that fall and enter the fluidized bed through the bottom of the tower can also be re-sprayed into the middle position of the spray drying tower cavity through the second fine powder particle conveying pipe under the airflow of the fluidized bed. The fine powder particles re-sprayed into the spray drying tower cavity through the first and second fine powder particle conveying pipes can meet the partially dehydrated microcapsule particles at the middle of the tower and undergo secondary agglomeration, forming larger microcapsule particles. This spray drying secondary agglomeration device can directly agglomerate small fine powder particles with microcapsule particles at the waist of the tower, reducing the time for fine powder particles to undergo high-temperature drying again in the tower and avoiding cracking or discoloration of microcapsule powder due to prolonged drying.

[0007] Typically, the spray drying tower, cyclone separator, and fluidized bed mentioned above can all be conventional equipment; the air inlet device can be a combination of an air inlet fan and an air filter, with the air outlet of the air inlet fan connected to the air inlet of the air filter, and the air outlet of the air filter connected to the top of the spray drying tower cavity; the exhaust device can be an exhaust fan, with the exhaust fan inlet connected to the top of the spray drying tower cavity, and the exhaust fan outlet connected to the gas inlet of the cyclone separator.

[0008] In a preferred embodiment, the secondary agglomeration device for spray drying further includes a converging pipe and multiple branch pipes. The discharge ends of both the first and second fine particle conveying pipes are connected to the converging pipe, and the inlet ends of each branch pipe are connected to the converging pipe. The discharge ends of each branch pipe are connected to the center of the spray drying tower cavity. Fine particles from the cyclone separator and fluidized bed can enter the converging pipe through the first and second fine particle conveying pipes for aggregation, and then be sent into the spray drying tower cavity through the branch pipes. By setting multiple branch pipes, the fine particles can be evenly dispersed into the tower.

[0009] In a further preferred embodiment, the discharge ends of each branch pipe extend into the middle of the spray drying tower cavity, and the discharge ends of each branch pipe are evenly arranged along the circumference of the spray drying tower. This arrangement allows for a more uniform distribution of fine powder particles within the tower.

[0010] In a further preferred embodiment, the number of branch pipes is three.

[0011] The beneficial effects of this invention are as follows: This spray drying secondary agglomeration device can directly agglomerate the fine powder particles with the microcapsule particles at the waist of the tower, reducing the time for the fine powder particles to undergo high-temperature drying again in the tower, and avoiding cracking or discoloration of the microcapsule powder due to prolonged drying. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of the spray drying secondary agglomeration device in the embodiment of this utility model;

[0013] Figure 2 for Figure 1 A sectional view along position A in the middle;

[0014] Figure 3 This is a schematic diagram of an existing agglomeration device. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0016] like Figure 1-2The spray drying secondary agglomeration device shown includes a spray drying tower 1, an air inlet device 2, a pressure spray gun 3, an exhaust device 4, a cyclone separator 5, a fluidized bed 6, a first fine powder particle conveying pipe 7, and a second fine powder particle conveying pipe 8. The spray drying tower 1 has a cavity, and the air inlet device 2 and the pressure spray gun 3 are located at the top of the cavity of the spray drying tower 1. The top of the cavity of the spray drying tower 1 is connected to the gas inlet of the cyclone separator 5 through the exhaust device 4. The bottom of the cavity of the spray drying tower 1 is connected to the feed inlet of the fluidized bed 6. The cyclone separator 5 and the fluidized bed 6 are respectively provided with fine powder particle outlets. The feed end of the first fine powder particle conveying pipe 7 is connected to the fine powder particle outlet of the cyclone separator 5, and the feed end of the second fine powder particle conveying pipe 8 is connected to the fine powder particle outlet of the fluidized bed 6. The discharge ends of the first fine powder particle conveying pipe 7 and the second fine powder particle conveying pipe 8 are both connected to the middle position of the cavity of the spray drying tower 1.

[0017] When the above-mentioned spray drying secondary agglomeration device is working, the spray drying tower 1 sprays the atomized liquid to obtain microcapsule particles, and then sends the obtained microcapsule particles into the fluidized bed 6 for further drying. During the above drying process, the air and fine powder particles at the top of the spray drying tower 1 cavity are sent to the cyclone separator 5 through the exhaust device 4. After separation by the cyclone separator 5, the fine powder particles are sprayed back into the middle position of the inner cavity of the spray drying tower 1 through the first fine powder particle conveying pipe 7. Similarly, the fine powder particles that fall and enter the fluidized bed 6 through the bottom of the tower can also be sprayed back into the middle position of the inner cavity of the spray drying tower 1 through the second fine powder particle conveying pipe 8 under the airflow of the fluidized bed 6. The fine powder particles that are sprayed back into the inner cavity of the spray drying tower 1 through the first fine powder particle conveying pipe 7 and the second fine powder particle conveying pipe 8 can meet the microcapsule particles that have lost some moisture at the middle of the tower and undergo secondary agglomeration to form larger microcapsule particles. This spray drying secondary agglomeration device can directly agglomerate small fine powder particles with microcapsule particles at the waist of the tower, reducing the time for fine powder particles to undergo high-temperature drying again in the tower and avoiding cracking or discoloration of microcapsule powder due to prolonged drying.

[0018] The spray drying tower 1, cyclone separator 5, and fluidized bed 6 mentioned above all use conventional equipment; the air inlet device 2 uses a combination of air inlet fan 201 and air filter 202, with the air outlet of air inlet fan 201 connected to the air inlet of air filter 202, and the air outlet of air filter 202 connected to the top of the cavity of spray drying tower 1; the exhaust device 4 can use an exhaust fan, with the air inlet of exhaust fan connected to the top of the cavity of spray drying tower 1, and the air outlet of exhaust fan connected to the gas inlet of cyclone separator 5.

[0019] The secondary agglomeration device for spray drying also includes a converging pipe 9 and three branch pipes 10. The discharge ends of the first fine powder conveying pipe 7 and the second fine powder conveying pipe 8 are both connected to the converging pipe 9. The inlet ends of each branch pipe 10 are connected to the converging pipe 9. The discharge ends of each branch pipe 10 extend into the middle of the spray drying tower 1 cavity, and the discharge ends of each branch pipe 10 are evenly arranged along the circumference of the spray drying tower 1. Fine powder particles from the cyclone separator 5 and the fluidized bed 6 can enter the converging pipe 9 through the first fine powder conveying pipe 7 and the second fine powder conveying pipe 8 for convergence, and then be sent into the spray drying tower 1 cavity through each branch pipe 10. By setting multiple branch pipes 10, fine powder particles can be evenly dispersed into the tower.

Claims

1. A spray drying secondary agglomeration device, comprising a spray drying tower, an air inlet device, a pressure spray gun, an exhaust device, a cyclone separator, and a fluidized bed, wherein the spray drying tower has a cavity, and the air inlet device and the pressure spray gun are disposed at the top of the cavity of the spray drying tower; the top of the cavity of the spray drying tower is connected to the gas inlet of the cyclone separator through the exhaust device; the bottom of the cavity of the spray drying tower is connected to the feed inlet of the fluidized bed; characterized in that: It also includes a first fine powder particle conveying pipe and a second fine powder particle conveying pipe. The cyclone separator and the fluidized bed are respectively provided with fine powder particle outlets. The feed end of the first fine powder particle conveying pipe is connected to the fine powder particle outlet of the cyclone separator, and the feed end of the second fine powder particle conveying pipe is connected to the fine powder particle outlet of the fluidized bed. The discharge ends of the first and second fine powder particle conveying pipes are both connected to the middle position of the spray drying tower cavity.

2. The spray drying secondary agglomeration device as described in claim 1, characterized in that: The spray drying secondary agglomeration device also includes a converging pipe and multiple branch pipes. The discharge ends of the first fine powder conveying pipe and the second fine powder conveying pipe are both connected to the converging pipe. The inlet ends of each branch pipe are connected to the converging pipe, and the discharge ends of each branch pipe are respectively connected to the middle position of the spray drying tower cavity.

3. The spray drying secondary agglomeration device as described in claim 2, characterized in that: The discharge ends of each branch pipe extend into the middle of the spray drying tower cavity, and the discharge ends of each branch pipe are evenly arranged along the circumference of the spray drying tower.

4. The spray drying secondary agglomeration device as described in claim 2, characterized in that: The number of branch pipes is three.

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