SU1478006A1 - Spray drier for heat-sensitive materials - Google Patents

Abstract

The invention can be used in the chemical and microbiological industries. The purpose of the invention is to improve the quality of drying and reduce energy consumption. The cylindrical drying chamber 1 has perforated side walls; a sprayer is arranged coaxially in the chamber. The camera is equipped with a smaller base facing upwards with a truncated cone bottom. The roof of the chamber 1 is made in the form of a truncated cone, facing the smaller base upwards. Cyclonic chambers 9 are installed between the nozzle of the gas suspension and the cyclone on the roof of chamber 1. Cameras 9 are connected via a material withdrawal line to a cyclone communicated along the coolant output line with an additional heat transfer nozzle. The sprayer is located at the smaller base of the chamber bottom. The nozzle of the sprayer is made with a variable cross-section, decreasing in the course of the coolant movement, is located outside the drying chamber 1 and is provided along its perimeter with trapezoidal blades installed tangentially to the drying chamber 1. The installation design allows for multiple contacting of the material being dried with the main and additional heat transfer media the volume of the drying chamber, as well as the circulation of the additional coolant within the installation using the heat of the exhaust air. 3 il.

Description

one

The invention relates to heat and mass transfer equipment, namely, spray drying installations for heat-sensitive materials, and can be used in the chemical, microbiological and other industries.

The purpose of the invention is to increase the quality of drying and reduce energy consumption.

Phip 1 shows a spray dryer for heat-sensitive materials; in fig. 2 is a section A-A in FIG. in FIG. 3, node I in FIG.

A spray dryer for heat-sensitive materials includes a cylindrical drying chamber 1 with perforated side walls, a sprayer made in the form of a perforated rotor 2, provided externally with a set of discs 3 forming annular slits, snail

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The initial heat-sensitive material is fed into the chamber through a rotating perforated rotor of 2 g and, thanks to annular slits formed by the disks J, is evenly distributed in the lower part of the drying chamber 1, directed to its perforated walls. Main heat carrier

10, the fuel fed to the dryer through the tangential nozzle 4 in the direction opposite to the direction of rotation of the rotor 2 picks up the source dried material and changes the direction of movement of the particles of the dried material to the opposite, while under the centrifugal force of the swirling air flow the particles of the material being dried are discarded

20 are adhered to the perforated walls of the chamber 1.

Such a change in the direction of movement of the material being dried in the volume of the drying chamber increases into the pipe 4 of the main heat transfer supply for 25 meters of the material being dried, made in the form of a transfer chamber in the chamber, while providing a cross section equipped with trapezoidal lines or curved blades around the perimeter. 5, the inlet 6 for introducing an additional coolant, connected to the perforated cylindrical chamber 1 by means of the cavity 7, the coaxial chamber I and located along its entire height. Cyclone 35 particles of the chamber 1 are dried to the wall of the discarded to the perforated roof 8 of the chamber 1

good contact of the material with the main coolant, and the blades 5 ensure uniform distribution of the main coolant in the volume of chamber 1 and contribute to the turbulence of the coolant flow.

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The initial heat-sensitive material is fed into the chamber through a rotating perforated rotor of 2 g and, thanks to annular slits formed by the disks J, is evenly distributed in the lower part of the drying chamber 1, directed to its perforated walls. The main heat carrier supplied to the dryer through the tangential nozzle 4 in the direction opposite to the direction of rotation of the rotor 2 picks up the source dried material and changes the direction of movement of the particles of the dried material to the opposite, while under the centrifugal force of the swirling air flow the particles of the material being dried are discarded 20 to the perforated walls of the chamber 1.

Such a change in the direction of movement of the material being dried in the volume of the drying chamber increases the residence time of the material to be dried in the chamber, while ensuring that the particles rejected to the perforated 35 walls of the chamber 1 dry up the stay of the material to be dried in the chamber, thereby providing the drops to the perforated walls of the chamber 1 particles are drying

good contact of the material with the main coolant, and the blades 5 ensure uniform distribution of the main coolant in the volume of chamber 1 and contribute to the turbulence of the coolant flow.

chambers 9, made of one or several axial cyclones installed in a set manner, equipped with axial swirlers 10 and nozzles 11 and 12 of the outlet of a part of air and the finished material and exhaust part of air. The dryer also includes a cyclone 13 for separating the finished product.

Part of the spent heated air is taken and returned to the drying chamber 1 as an additional coolant by fan 14 through line 15 connecting the cyclone 13 and the cavity 7. The dried material is discharged through the nozzle 16. The drying chamber 1 is provided with a bottom 17 in the form of a truncated cone oriented smaller base towards the drying chamber.

Spray dryer works as follows.

the material is picked up by the flow of additional coolant entering the drying chamber through the perforated walls, again

They change the direction of their movement and, under the influence of the mixture of the main and additional coolants, are directed towards the cyclone chambers 9, while the contact of the material with the heat carrier continues. The gradual mixing of primary and secondary coolants in the volume of the drying chamber and repeated changes in the direction of movement of the particles of the material being dried in the volume of the drying chamber 1 provide optimal soft conditions for drying the heat-sensitive materials. In the cyclone chambers 9, due to the axial swirlers 10, the flow is again twisted, while the particles of the dried material are thrown to the walls of the chambers 9 and with part of the air through the pipes 11 and through the pipeline enter the cyclone

0

five

13, where the dried material is discharged through the pipe tb, and the air through line 15 through the fan 14 as an additional heat transfer fluid enters through the pipe 6 into the cavity 7 and is evenly supplied through the perforated walls to the drying chamber 1. Part of the exhaust air is discharged from the dryer through the pipe 12.

Thus, the design of the proposed drying unit allows multiple contacting of the dried material with the main and additional coolants in the volume of the drying chamber and the circulation of the additional coolant within the plant using the heat of exhaust air, thereby improving the quality of heat-sensitive drying. materials and reduced energy costs

the implementation of the drying process

Claims (1)

Invention Formula Spray dryer for heat-sensitive materials, containing a cylindrical drying chamber with perforated side walls, with an inverted smaller base Q five 0 upward by a truncated cone bottom coaxially located in the chamber a sprayer with its snail tangential inlet of the coolant inlet, outlet of the gaseous spring in the upper part connected to the cyclone with the drying chamber enclosed in the casing with the formation of an additional heat carrier between them , characterized in that, in order to improve the quality of drying and reduce energy consumption, the roof of the chamber is made in the form of a truncated cone, with the smaller base facing up, and between the patra The cyclone chambers connected along the material discharge line to the cyclone, in turn, along the output line of the coolant with the inlet pipe of the additional coolant, while the sprayer is located at the smaller base of the bottom, and its branch pipe is made with variable cross-section, decreasing in the course of the coolant movement, is located outside the drying chamber and is provided along its perimeter with trapezoidal blades set tangentially to shilnoy chamber. 0ag.Z