RU2347993C1 - Pseudoliquid layer drier with inert headpiece "l"6 - Google Patents

Abstract

FIELD: heating; drying.

SUBSTANCE: present invention pertains to the technology of drying particulates in a boiling bed and can be used in anilino-dye, food, pharmaceutical, microbiological, chemical and other industries. The pseudoliquid layer drier with an inert head piece has a drying chamber with an atomiser, gas-distributing array in form a packet of grids made from springs, lying in the same plane and joined to vibrating plates of a vibration mechanism, fitted in the drying chamber with provision for rotating about axes. On the vibrating plates, more plates with different lengths are rigidly fixed in chequered fashion, at an angle of 80…40° to the vibrating plates. The free tops of the extra plates on the right side of the vibrating plates face upwards, while those on the left side face downwards. In the top part of the chamber there is trapping system, comprising an acoustic device, where there is acoustic agglomeration of fine particles, a cyclone and a bag filter with a storage bin. The atomiser is acoustic and has a case, inside of which there is an acoustic generator in form of a nozzle and a resonator, a pipe for supplying air and liquid. The case is in form of a cup with a bottom, in which there is a cylindrical cavity for letting liquid into the pipe, located on the cover, in the top part of which there is a fastener, fixing the top part of the rod of the rod-type jet-edge generator in the nozzle on the cover. The top part of the rod is pivotally joined to the bottom part of the generator on the cover by at least, one locking disc, made in form of at least, three elastic blades, linked to the inner surface of the cone-shaped opening on the cover. Between the opening on the bottom of the case and the inner surface of the nozzle on the cover, there is parallel-plate duct, along which liquid flows. Between the inner surface of the cone-shaped opening and the outer surface of the bottom part of the rod, there is an annular channel, on which the atomising agent flows.

EFFECT: increased drying output.

2 cl, 4 dwg

Description

The invention relates to techniques for drying dispersed materials in a fluidized bed and can be used in aniline-paint, food, pharmaceutical, microbiological, food, chemical and other industries.

The closest technical solution to the claimed object is a dryer for drying solutions, suspensions and pastes in a fluidized bed by.with. USSR No. 370423, F26B 17/10, 1975, comprising a housing with a perforated motionlessly fixed gas distribution grill with an inert nozzle, an atomizer, a vibration mechanism made in the form of plates mounted in the dryer body with the possibility of rotation about axes kinematically connected with the cam and managed by him according to a given law (prototype).

The disadvantage of the prototype is the relatively low productivity of drying the final product, since in the known installation, the liquefaction of a layer of inert bodies is achieved due to the shock effects of the vibrating plates. However, the vibration of the plates is transmitted only to the layer of inert bodies adjacent to them, therefore, the remaining mass of the layer liquefies less intensively, which is especially evident when working on plants with large dimensions.

The technical result is an increase in drying performance.

This is achieved by the fact that in a fluidized bed dryer with an inert nozzle containing a drying chamber with a nozzle, a gas distribution grid in the form of a packet of grids assembled from springs located in the same plane and connected to vibrating plates of a vibration mechanism installed in the drying chamber with the possibility of rotation relative to axes according to the invention on the vibrating plates in a checkerboard pattern, additional plates of different lengths are rigidly fixed at an angle to the vibrating plates lying in the range it is, for example, 80 ... 40 °, and the free vertices of the additional plates at the right vibrating plate are facing up, and at the left - down, in the upper part of the chamber there is a trapping system, which includes an acoustic unit where acoustic agglomeration of small particles, a cyclone and bag filter with a hopper, and the nozzle is made acoustic and contains a housing with an acoustic oscillator located inside the nozzle and resonator, tubes for supplying air and liquid, and the housing is made in the form of a glass with a bottom in which a cylindrical cavity is made for supplying fluid through a tube located in the cap, in the upper part of which there is a fastening element fixing the upper part of the rod of the rod gas-jet emitter in the nozzle made in the cap, and the upper part of the rod is pivotally connected to the lower part of the emitter in the cap at least one fixing disk made in the form of at least three elastic petals interacting with the inner surface of the conical opening of the cover, and between a hole is made in the bottom of the housing and the outer surface of the cap nozzle through which liquid enters, between the inner surface of the conical hole and the outer surface of the lower part of the rod an annular channel is made through which the spraying agent enters.

Figure 1 shows the dryer of the suspended layer with an inert nozzle, General view; figure 2 and figure 3 shows the options for performing the lattice, figure 4 is a diagram of an acoustic pneumatic nozzle.

The dryer of the suspended layer with an inert nozzle consists of a drying chamber 1 of a conical rectangular cross-section, in the upper part of which there is a feeder for pastes or an acoustic pneumatic nozzle 2 for spraying solutions.

The drying chamber 1 is equipped with nozzles of the input 11 and output 3 of the coolant. Inside the chambers there are two (left and right) vibrating plates 4 mounted at a certain angle to the inert material layer, for example 30 ... 40 °. The vibrating plates 4 at a distance of about 2/3 from the upper end are pivotally mounted on the axis of the shaft 5 in the housing of the drying chamber, which allows them to oscillate relative to the axes of the shaft 5. On the vibrating plates 4, additional plates 9 and 10 of different lengths are rigidly fixed angle to the vibrating plates 4, lying in the range, for example, 80 ... 40 °, and the free vertices of the additional plates 9 and 10 at the right vibrating plate 4 are facing up, and at the left (not shown) - down. Additional plates 9 and 10 serve for more intensive mixing of the inert nozzle.

The lower ends of the vibrating plates 4 are connected to a gas distribution grid 6, made in the form of a grid of metal springs connected or in contact with each other. Vibrating plates 4 together with a spring gas distribution grid 6 transmit dynamic and static effects to a layer of inert material and give it a certain law of motion, which is achieved by the angle of inclination of the vibrating plates 4, the cam profile 7 and the number of revolutions. A cam 7 is mounted on a drive shaft (not shown). The cam is used to set a specific, for example, sinusoidal law of motion of the vibrating plates 4 and the spring distribution grid 6. The rods 8, rigidly mounted on the axis of the vibrating plates 4, are pressed against the cam 7 by the springs of the gas distribution grid 6.

As a feeder for the wet initial product in this dryer, an acoustic nozzle is used (Fig. 4), which comprises a housing 20 made in the form of a cup with a bottom, in which a cylindrical cavity 16 is made for supplying fluid through a tube 31 located in the cover 21. In the housing 20 the nozzle has a cylindrical groove 23 in which an elastic sealing element 24 is located, and the cover 21 and the housing 20 are connected by screws 22. In the upper part of the cover there is a fastening element 25 that fixes the upper part of the rod gas 27 Hartmann jet emitter 19 in the nozzle 33. At the gap 26 enters the channel 33 of the spray nozzle agent. Between the hole in the bottom of the housing 20 and the outer surface of the nozzle 33 of the cover 21, a slotted channel 17 is made, through which liquid enters. An annular channel 18 is provided between the inner surface of the conical hole 32 and the outer surface of the lower part of the rod 28, through which a spraying agent, such as air, enters.

The upper part of the rod 27 is pivotally connected to the lower part of the rod 28, which is fixed relative to the conical hole 32 made in the cover 21, by means of at least one fixing disk 29 made in the form of at least three elastic petals 30 interacting with the inner surface of the conical hole of the cover 21.

For optimal operation of the nozzle, the following ratios of its parameters must be observed:

- the ratio of the height h _{1 of the} emitter 19 to the distance h between the upper base of the conical surface 34 and the lower end surface of the nozzle 33 lies in the optimal range of values: h ₁ / h = 1 ÷ 3;

- the ratio of the inner diameter d _{1 of the} cavity 35 of the emitter d ₂ to the diameter h of its outer cylindrical surface lies in the optimal range of values: d ₁ / d ₂ = 0.7-0.9;

- the ratio of the inner diameter d _{1 of the} cavity 35 of the emitter 19 to the diameter d of its rod lies in the optimal range of values: d ₁ / d = 1 ÷ 3;

- the ratio of the inner diameter d _{1 of the} cavity 35 of the emitter 19 to the height h _{1 of the} cavity 20 lies in the optimal range of values: d ₁ / h ₁ = 1 ÷ 1,5.

A fluidized bed dryer with an inert packing works as follows.

The required amount of inert material is loaded into the drying chamber 1, then the drive is turned on, from which the cam 7 rotates. The latter, through the rods mounted on the shaft axis 5 of the vibrating plates 4, transmits the movement to the vibrating plates and the gas distribution grid 6. Shock-vibration effects of the vibrating plates 4 s additional plates 9 and 10 and the springs of the gas distribution grid 6 are transferred to the layer of particles of inert material, which, when impacted, make complex circulation movements in the drying chamber 1. the jug 11 is supplied with a heat carrier that heats the drying chamber 1 and the inert material layer, while the dryer operates on the principle of a "fluidized bed" of inert material. Through an acoustic pneumatic nozzle 2, a dried material is fed into the drying chamber 1, which is sprayed or smeared on the upper layer of an inert material, then dried, chipped, and sent to a trapping system: first, into an acoustic unit 12, where acoustic agglomeration of small particles occurs, and then into a cyclone 13 and bag filter 14 with hopper 15.

In the proposed dryer, the gas distribution grid 6 is made in the form of a packet of grids assembled from metal springs (FIGS. 2, 3), connected or in contact with one another, which are connected to vibrating plates.

Such a gas distribution lattice makes it possible to more evenly liquefy a layer of inert bodies due to the oscillatory movement of the vibrating plates and the influence of inertia on them arising from the pulsating compressive-tensile movements of the gas distribution lattice. This design of the gas distribution grid solves the problem of its cleaning when drying sticky materials. The continuous regeneration of the mesh lattice occurs as a result of the constant displacement of the individual lattice elements relative to each other during vibration.

The acoustic nozzle for spraying liquids works as follows. Liquid under pressure is supplied to a cylindrical cavity 16 located outside the emitter 19, from where it flows through the slotted channel 17 in the form of a film, which is exposed to fluctuations in velocity and pressure generated by pulsating shock waves that occur near the annular channel 18 due to the supersonic jet flowing onto the resonator 19. As a result, the film is crushed into small droplets, which together with the air stream form a torch of atomized liquid.

As a result of drying, fine powders of products with a moisture content of up to 0.8% are obtained.

Claims (2)

1. The fluidized bed dryer with an inert nozzle, containing a drying chamber with a nozzle, a gas distribution grid in the form of a packet of grids assembled from springs located in the same plane and connected to the vibrating plates of the vibration mechanism installed in the drying chamber with the possibility of rotation relative to the axes, characterized in that on the vibrating plates staggered rigidly fixed additional plates of different lengths at an angle to the vibrating plates lying in the range, for example 80 - 40 °, m the free vertices of the additional plates at the right vibrating plate are facing up and at the left - down, at the top of the chamber there is a capture system that includes an acoustic unit where acoustic agglomeration of small particles, a cyclone and a bag filter with a hopper are performed, and the nozzle is made acoustic and contains a housing with an acoustic oscillator located inside the nozzle and resonator, tubes for supplying air and liquid, and the housing is made in the form of a glass with a bottom, in which the cylinder an indrical cavity for supplying fluid through a tube located in the cap, in the upper part of which there is a fastener fixing the upper part of the rod of the rod gas-jet emitter in the nozzle made in the cap, and the upper part of the rod is pivotally connected to the lower part of the radiator in the cap, at least , by means of one fixing disk, made in the form of at least three elastic petals interacting with the inner surface of the conical opening of the cover, and between the hole in the bottom of the housing and the outer surface of the nozzle cover is configured slotted channel through which fluid flows between the inner surface of the conical hole and the outer surface of the lower part of the rod an annular channel through which the atomizing agent is supplied. 2. The dryer according to claim 1, characterized in that the ratio of the height h _{1 of the} emitter to the distance h between the upper base of the conical surface and the lower end surface of the nozzle lies in the optimal range of values: h ₁ / h = 1 ÷ 3; the ratio of the inner diameter d _{1 of} the emitter cavity to the diameter d _{2 of} its outer cylindrical surface lies in the optimal range of values: d ₁ / d ₂ = 0.7 ÷ 0.9; the ratio of the inner diameter d _{1 of} the emitter cavity to the diameter d of its rod lies in the optimal range of values: d ₁ / d = 1 ÷ 3; the ratio of the inner diameter d _{1 of} the emitter cavity to the height h _{1 of the} cavity lies in the optimal range of values: d ₁ / h ₁ = 1 ÷ 1,5.

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