CN-115518583-B - Graded heating directional circulating spray fluidized bed

CN115518583BCN 115518583 BCN115518583 BCN 115518583BCN-115518583-B

Abstract

The invention provides a graded heating directional circulating spray fluidized bed, which consists of a plurality of groups of spray drying basic units which are sequentially connected. Each group of spray drying basic units comprises an air distribution plate, a nozzle, a first partition plate, a second partition plate, an inclined plate and the like. The first partition plate and the second partition plate are arranged at intervals to form a plurality of groups of connected high-speed beds and low-speed beds. The nozzle is inserted from the center of the air distribution plate of the high-speed bed, the nozzle is positioned above the air distribution plate, and the inclined plate is positioned on the low-speed bed. The temperature of the fluidizing air passed through each group of basic units is increased in turn. Whereby the granules form a regularly ordered directional circulation from the high-speed bed to the low-speed bed and then to the high-speed bed, and the coating solution is obtained in stages during the circulation and dried to form the coating layer. The invention has simple structure and reasonable design, realizes directional movement and graded heating of particles by regulating the fluidization wind speed and the wind temperature through the high and low partition plates, is beneficial to controllable drying and uniform flow of the particles, and improves the uniformity of particle coating.

Inventors

LIU DAOYIN
GUO JINNAN
MA JILIANG
CHEN XIAOPING
LIANG CAI

Assignees

东南大学

Dates

Publication Date: 20260508
Application Date: 20220926

Claims (5)

1. The spray drying basic units comprise a high-speed bed (1) and a low-speed bed (2), the fluidized beds integrally form a structure with the high-speed bed (1) and the low-speed bed (2) arranged at intervals in sequence, the bottoms of the high-speed bed (1) and the low-speed bed (2) are respectively provided with a high-speed air distribution plate (3) and a low-speed air distribution plate (4), a first partition plate (5) is arranged in the spray drying basic units to separate the high-speed bed (1) and the low-speed bed (2), a second partition plate (6) is arranged on the outer side of the spray drying basic units, circulation holes (7) are formed in the bottoms of the second partition plates (6), nozzles (8) are arranged on the high-speed air distribution plates (3), high-speed fluidization air (11) is introduced into the high-speed bed (1), and low-speed fluidization air (12) is introduced into the low-speed bed (2) from the low-speed air distribution plates (4); the temperature of the fluidization wind entering through the high-speed air distribution plate (3) and the low-speed air distribution plate (4) is sequentially increased along the flowing direction of particles in the fluidized bed; the bottom of the low-speed bed (2) is provided with an inclined plate (9), and the inclined plate (9) gradually inclines downwards along the direction from the first baffle plate (5) to the second baffle plate (6); the wind speeds of high-speed fluidization wind (11) and low-speed fluidization wind (12) which are introduced from the high-speed air distribution plate (3) and the low-speed air distribution plate (4) can be respectively and independently adjusted; the spray nozzle (8) at the bottom of the high-speed bed (1) sprays spray into the high-speed bed (1), the spray is attached to the surface of the particles, the gradual heating of fluidization wind along with the forward movement of the particles in the fluidized bed realizes the graded heating of the particles, the particles are effectively dried, the particles form regular and orderly directional circulation from the high-speed bed (1) to the low-speed bed (2) and then to the next high-speed bed (1), and coating solution is obtained in stages in the circulation process, and the coating layer is formed by drying.
2. The staged heating directional circulating spray fluidized bed according to claim 1, wherein the inclined plate (9) is of a net structure, and small holes are arranged on the inclined plate.
3. A staged heated directed cycle spray fluidized bed according to claim 2 wherein the orifices have diameters less than the diameter of the particles in the fluidized bed.
4. The staged heating directional circulating spray fluidized bed according to claim 1, wherein the nozzles (8) are arranged in the center of the Gao Subu air plate (3), and the bottoms of the nozzles (8) are connected in series through a pipeline (10).
5. A staged heated directed cycle spray fluidized bed according to claim 1 wherein the spray drying base units are provided with n groups wherein n is greater than or equal to 2.

Description

Graded heating directional circulating spray fluidized bed Technical Field The invention relates to the technical field of spray fluidized beds, in particular to a graded heating directional circulating spray fluidized bed. Background The spray fluidized bed has high-efficiency granulation characteristic and excellent heat and mass transfer performance, can efficiently realize the coating and agglomeration of particles, and is widely applied to the fields of food, pharmacy, chemical industry, energy sources, environment and the like. Studies have shown that the circulation time profile plays a key role in the uniformity of the particle coating in a directional spray fluidized bed. However, the circulation time profile is affected by the fluidized bed structure and the operating conditions. The particles form a regular and orderly directional flow field, so that the circulation time distribution of the particles is effectively controlled. The particle circulation time distribution plays a decisive role in the uniformity of particle growth. In production, the materials are required to be effectively dried, the coating effect is poor due to untimely drying, and the spray fluidized bed is provided with nozzles in a concentrated manner, so that concentrated spraying is caused, the moisture content is high, and the drying of particles is not facilitated. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a graded heating directional circulating spray fluidized bed which can realize the directional movement and graded heating of particles, is beneficial to the controllable drying and uniform and consistent flow of the particles, and effectively improves the uniformity of particle coating. In order to solve the technical problems, the invention provides the following technical scheme: The spray drying basic units comprise a high-speed bed and a low-speed bed, the high-speed bed and the low-speed bed are sequentially arranged at intervals, a high-speed air distribution plate and a low-speed air distribution plate are respectively arranged at the bottoms of the high-speed bed and the low-speed bed, a first partition plate is arranged in the spray drying basic units to separate the high-speed bed and the low-speed bed, a second partition plate is arranged on the outer side of the spray drying basic units, circulation holes are formed in the bottoms of the second partition plates, nozzles are arranged on the high-speed air distribution plates, high-speed fluidization air is introduced into the high-speed bed from the high-speed air distribution plate, and low-speed fluidization air is introduced into the low-speed bed from the low-speed air distribution plate. Further, the temperature of the fluidizing air entering through the high-speed air distribution plate and the low-speed air distribution plate is sequentially increased along the flowing direction of the particles in the fluidized bed. Further, the bottom of the low-speed bed is provided with an inclined plate which gradually inclines downwards along the direction from the first baffle plate to the second baffle plate. Further, the inclined plate is of a net structure, and small holes are distributed on the inclined plate. Further, the diameter of the small holes is smaller than the diameter of particles in the fluidized bed. Further, the nozzles are arranged in the center of the Gao Subu air plate, and the bottoms of the nozzles are connected in series through pipelines. Further, the spray drying basic unit is provided with n groups, wherein n is more than or equal to 2. Further, the wind speeds of the high-speed fluidization wind and the low-speed fluidization wind which are introduced from the high-speed air distribution plate and the low-speed air distribution plate can be respectively and independently adjusted. Compared with the prior art, the invention has the beneficial effects that: 1. according to the graded heating directional circulating spray fluidized bed, the flow velocity of the fluidization air communicated by the two adjacent compartment air distribution plates is different, the air inlet of the air distribution plate below the nozzle is high-speed fluidization air, the air inlet of the air distribution plate below the inclined plate is low-speed fluidization air, and the directional movement of particles can be independently controlled by adjusting the speed of secondary air, so that the particles can circulate well in the fluidization device. 2. According to the graded heating directional circulating spray fluidized bed, the temperature of the fluidization air entering the air distribution plate of each group of spray drying basic units is sequentially increased, so that graded heating of particles is realized, the particles are effectively dried, and the uniformity of particle coating is improved. 3. The staged heating directional circulating spray fluidized bed has the advantages that a group of high-speed