SU624080A1 - Method of drying dispersed suspended materials - Google Patents

Description

(54) METHOD FOR DRYING DISPERSED MATERIALS IN THE WEIGHTED CONDITION

The invention relates to a technique for drying dispersed materials, preferably highly moist adhering materials, such as, for example, mineral salts, citric acid, yeast, and be used in the ore, chemical, food and other industries.

There is a known method of drying dispersed materials in the cocked state with their partial recycling by means of pneumatic transport of the gas suspension in the upstream and introducing the Tl adsorbent into it.

The disadvantage of this method is the violation of the drying mode when processing sticky high-moisture materials, which reduces the reliability and intensity of heat and mass transfer.

The purpose of the invention is to intensify heat and mass transfer and increase reliability when drying high-moisture materials.

This is achieved by the fact that according to the proposed method, the adsorbent is injected into the gas suspension in a dispersed manner with the help of an additional heat carrier flow at a condensation of 2–5 kg / kg, and it is displaced in a flow through the gas suspension and

at a speed exceeding 1.5 times the speed of a pedal.

The drawing shows schematically an installation for implementing the described method.

The installation includes a hopper 1 of wet material, a tape feeder 2, an inclined feed chute 3, a dryer pipe 4, and nozzles 5

for supplying the dust-gas heat carrier, cyclone 6, adsorbent bunker 7 (dry dispersed material), pipelines 8 and 9 for supplying the main and additional coolant flows.

The installation works as follows.

Wet material from the hopper 1 is fed to a belt dryer-feeder 2, and from it into an inclined ostka 3. From an oblique ostka, the material enters the pipe-dryer 4. Falls and the rising flow of heat-transfer fluid entering the pipe-dryer 4 through pipeline 8, wet the material initially moves downward by inertia, is slowed down by the main flow of the coolant, and then transported upwards, dried in a chimney 4 pipe and

Claims (1)

It enters the separation into the cyclone 6. From the cyclone 6. a part of the dried dispersed material is sent to the bunker 7, and the other part is sent to the finished product. From the bunker 7, the adsorbent, entering the pipeline 9, is picked up by the flow of heat-transfer fluid, flows through it and through the nozzles 5 dispersed on the wall of the pipe-dryer 4 in the place opposite to the loading point of the wet material, in the form of a dust-and-air flow goes to the pipe-dryer 4. fine fractions of the material after the second stage of purification (not shown) enter the bunker .7 These fractions often reduce the grade of the main product. A coolant of the same temperature as that of the pipeline 8 can be supplied to the pipe 9. If the pipeline 8 is supplied with a coolant with a temperature higher than the melting / decomposition temperature, sublimation, etc. dry material, a mixture of hot coolant and ambient air is supplied to pipeline 9. Dusty gas flow doubles the flow of moist material: first, mixing both flows reduces the moisture of the source material due to contact heat and mass, and secondly, the dust and gas flow pushes the flow of wet material away from the opposite location of the wet supply. wall material and aligns the upward flow. The living force of the injected dust-gas flow, determined by the product of its mass and velocity, must not be less than the horizontal component of the living force of the flow of wet material in the dryer tube 4. In order to carry out the above processes, it is necessary that, first, the amount of dry material should be 5–20% of the amount of the initial wet material (depending on the initial moisture content of the material), and, secondly, the speed of the dust-gas flow was 1.2–1.5 times the speed of the ascending coolant. The concentration should be 2-5 kg / kg. In addition, the concentration of the dust-gas flow of 2–5 kg / kg provides a relatively small amount of additional coolant (hot gases or a mixture of air with hot gases). Thus, the proposed drying method makes it possible to improve the upstream flow hydrodynamic structure. the most critical place is where the wet material is loaded, which intensifies heat and mass transfer, and also prevents the wet material from sticking to the walls of the dryer tube 4, which increases the operational reliability of its operation. The invention of the method of drying dispersed materials in a suspended state with their partial recycling by means of pneumatic transport of a gas suspension in the upstream and introduction of an adsorbent into it, which in order to intensify heat and mass transfer and increase reliability when drying high-moisture materials, the adsorbent into the gas suspension t dispersed in height with the help of additional coolant flow at a concentration of 2-5 kg / kg, and its movement is carried out in the air flow and at a speed exceeding 1.2-1.5 times for the speed of the latter. Sources of information taken into account in the examination: 1. USSR Author's Certificate No. 539209, cl. R 26 B 3/10, 1975.