UA137932U - Louvered bed with an optimal angle of inclination - Google Patents

Abstract

The invention relates to devices for drying heat-sensitive materials such as grains. A louvered bed for drying free-flowing materials comprises a series of identical angular elements fastened in a housing and arranged in parallel and horizontally overlapping, with a space between the angular elements, each angular element comprising two shelves mounted at a right angle to each other, and is characterized in that the shelves of an angular element are not alike, one being broad and the other narrow, the angular elements are mounted such that the angle between the shelves is situated higher than the shelves themselves, and the angle of inclination of the base of the bed is from 4 to 8 degrees. The technical result is increased energy efficiency, more uniform drying of the raw material, and reduced damage to grains.

Description

A useful model belongs to devices for drying heat-sensitive materials, such as grain.

The well-known "Air chute for drying loose and non-loose materials", KO 2365836, which includes a bed for placing the materials to be dried on top of the bed and a device for supplying drying gas to the lower part of the bed, means of transporting the materials to be dried, while the bed is composed of equal-shelf corner elements installed parallel to intervals for the supply of drying gas, and the angle between the shelves of equal-shelf elements is straight.

The disadvantage of the device is the increased complexity of the device, which leads to low reliability and durability.

The closest analogue of the useful model is "Equipment for drying loose materials in a fluidized bed" KO 2100723, which contains a louvered bed for drying loose materials, which consists of a series of identical corner elements fixed in the body, located parallel and flush with a gap between the elements. The target channels are directed towards the discharge and upwards at an angle of 7-10 degrees to the horizontal.

The device is characterized by increased reliability and durability due to the simplification of the device, as well as due to the provision of a continuous process of drying materials.

The disadvantage is low energy efficiency due to the need for a fan of increased power for lifting and transporting grain. The disadvantage is also the increased traumatism of the grain and the instability of the drying results, due to the instability of movement during grain drying.

The useful model is based on the task of increasing energy efficiency, increasing uniformity of raw material drying, and reducing grain injury.

The task is solved by the fact that the louvered bed for drying loose materials contains a series of identical corner elements fixed in the body, located parallel and overlapping horizontally (overlap) with a gap between the corner elements, each corner element contains two shelves installed at right angles to each other one, according to a useful model, the shelves of the corner element are not equal to each other, one is wide, the other is narrow, while the corner elements are installed in such a way that the corner between the shelves is located higher than

From the shelves themselves, and the angle of inclination of the base of the bed is from 4 to 8 degrees.

The distance between wide shelves vertically can be 2-10 mm, and the distance between narrow shelves horizontally can be 30-70 mm. The specified parameters will make it possible to achieve high drying productivity with relatively low energy consumption.

The width of the wide shelf of the corner element can be 50-150 mm. Corner elements with the specified width range can provide optimal dimensions of the drying areas of the blind bed.

The width of a narrow shelf can be 10-40 mm. The specified range will make it possible to obtain sufficient strength to ensure the necessary resistance to bending of the corner element.

The corner between the shelves can be rounded, and the plates are made by stamping from a metal sheet with a thickness of 0.9-1.5 mm. The production of plates by the stamping method will make it possible to simplify the production technology, the specified thickness of the material is sufficient to achieve the required strength of the corner plates of the blind bed.

The device is schematically shown in the drawing (vertical longitudinal section of the bed), where: 1- narrow shelf; 2 - wide shelf;

C - angle of inclination of a wide shelf; 4 - a layer of material for drying; 5 - angle of inclination of the base of the bed.

The device works as follows: on a louvered bed, fixed in a housing (not shown), grain or other material for drying enters from above. A coolant, hot or cold gas, enters from below the louvered bed and passes through the grain layer into the space above the grain.

A layer of drying material, such as grain 4, is moved using, for example, a rail conveyor (not shown). Corner elements of the bed are congruent, each of them contains a narrow shelf 1 and a wide shelf 2 with a straight rounded corner between the shelves. The angle of inclination of the base (substrate) of bed 5 is in the range of 4-8 degrees. The angle of inclination of the wide shelf Z is smaller than the angle of inclination of the base of the bed by an angle determined by the ratio of the distance between the shelves vertically to the distance between the narrow shelves horizontally, and can be 2-4 degrees.

The slope of the base of the bed is directed towards the discharge, to the right and down (see drawing). The angle of external friction for grain and stainless steel is about 8 degrees. on grain

located above the louvered bed, the force of gravity, the force of aerodynamic resistance to the air flow, the force of friction against the surface of the louvered bed, forces from the rail conveyor (not shown) are acting. Accordingly, to prevent uncontrolled spilling of grain down along the bed, the angle of inclination of the bed should be much smaller than the angle of external friction, taking into account the performance and head (pressure drop) of the fan, which ensures the flow of gases through the layer, and the total area of the louvered bed, since the interaction with the horizontally directed the flow of gases causes additional shearing forces on the grain and reduces the critical angle at which the grain freely spills down along the sloping blind bed. In the areas between the end of one wide plate and the plane of the adjacent plate, the angle is larger than the critical one, which makes it easier to pour over and partially mix the grain, which, in turn, contributes to more uniform drying of the entire mass of grain. Along the plate, the angle of inclination of which is smaller than the critical one, the grain moves uniformly, without mixing, which reduces the traumatism of the grain.

If the angle of inclination of the base of the bed increases more than the critical 8 degrees during the operation of the dryer, uncontrolled spilling of grain down along the bed occurs, which leads to uneven drying and clogging of the lower part of the bed, which leads to an emergency situation. If the angle of inclination of the base of the bed is reduced to less than 4 degrees, there is a sharp increase in the load on the conveyor and an increase in grain injury caused by the increase in the mechanical effort of the conveyor to move the grain or other dried product along the louvered bed. In addition, the part of the grain close to the end of the wide shelf is immobilized, because the vibration and pressure of the coolant flow are not enough to remove the grains on their own. Immobilized grains increase air resistance, reduce the efficiency of the installation due to the aerodynamic shadow, these grains themselves dry out and increase the fire hazard of the installation.

Technical result - increasing energy efficiency is achieved by reducing the power of the conveyor; increasing the uniformity of raw material drying is achieved by optimal grain movement conditions with alternating laminar and turbulent modes of movement of the grain flow along the surface of the louvered bed without the use of significant energy costs to ensure the specified modes; reduction of grain injury is achieved by reducing the mechanical force of the conveyor on the grain.

Industrial application. The useful model can be successfully used for the production and operation of devices for drying grain and other loose raw materials.

Claims (5)

USEFUL MODEL FORMULA 1. A louvered bed for drying loose materials, which contains a series of identical corner elements fixed in the body, arranged in parallel and overlapping horizontally with a space between the corner elements, each corner element containing two shelves installed at right angles to each other, which differs in that the shelves of the corner element are not equal to each other, one is wide, the other is narrow, while the corner elements are installed in such a way that the angle between the shelves is located higher than the shelves themselves, and the angle of inclination of the base of the bed is from 4 to 8 degrees. 2. A bed according to claim 1, which differs in that the distance between wide shelves vertically is 2-10 mm, and the distance between narrow shelves horizontally is 30-70 mm. 3. A bed according to claim 1, which differs in that the width of the wide shelf of the corner element is 50-150 mm. 4. A bed according to claim 1, which differs in that the width of the narrow shelf is 10-40 mm. 5. A bed according to claim 1, which differs in that the corner between the shelves is rounded, and the plates are made by stamping from a metal sheet with a thickness of 0.9-1.5 mm. a shi chn 4 t Elena spek VEU VE chA tya lu 2 p NK In EN 5 Shchi 0 she u M zh yo E E Ben say ZheKM nova zhen nm oso kuvet kr Z s i. m ku z