Combined press dryer for polydisperse products

Abstract

The utility model relates to devices for dehydrating high-moisture polydisperse products of plant origin (beet pulp, apple pomace, etc.) and can be used in food and chemical industries. A combined press dryer for polydisperse products comprises a vertical body, having a cylindrical shape in the upper part, inside which a perforated filter chamber with a coaxially located hollow porous screw, a granulating part located in the lower end part of the perforated filter chamber, and a vibration dryer are coaxially located, wherein the hollow porous screw contains a central shaft smoothly increasing in thickness from top to bottom with screw blades fixed thereon, made with a variable decreasing pitch and height in the course of movement of the material from the loading zone in the upper part of the screw to the unloading zone in its lower part,wherein counter blades are mounted on the inner surface of the perforated filter chamber between the turns of the screw blades, and the perforated filter chamber is rigidly connected to the perforated truncated cone of the vibration dryer, made of an aluminum alloy with high thermal conductivity, mounted with the possibility of reciprocating movement, and the granulating part is provided with conical openings expanding upward, the large bases of which are oriented towards the working cavity of the filter chamber. The technical result consists in increasing the degree of mechanical dehydration and drying efficiency, and reducing energy costs. 1 fig.,

Description

[0001] This utility model relates to devices for dehydration of high-moisture polydisperse products of plant origin (beet pulp, apple pomace, etc.) and can be used in food and chemical industries.

[0002] A device for filtering and subsequent drying is known (Positive decision of Kazpatent on application No. 950451.1 in the National Patent Office of the Republic of Kazakhstan, B01D 29 / 64; F2617 / 10; F26B 11 / 04), including a filter housing with a porous drum located inside it; a screw made hollow and porous in the filter chamber, and solid in the squeezing chamber; a vibration dryer, inside which heating elements are installed; a gearbox transmitting axial rotation to the filter screw and simultaneously serving as a vibration exciter for the drying chamber.

[0003] The disadvantage of this installation is the impossibility of using vibration at the filtering and pressing stage, as well as the design of the dryer, which does not take into account the specifics of the alternating movement of the product, as well as the implementation of the processes of mechanical separation of the liquid phase from the solid (mechanical dehydration of the product) and drying in different housings, which increases the dimensions and metal consumption of the press dryer design.

[0004] The closest analogue in technical essence and achieved effect to the problem being solved (prototype) is a vibration press dryer for polydisperse products according to patent RU 2332627 C1, which contains a vertical housing, a filter chamber in the form of a truncated cone, a hollow porous screw, a squeezing (granulating) part, a vibration dryer with a perforated truncated cone and a helical chute, a common drive providing rotation and reciprocating motion.

[0005] The disadvantages of the vibration press dryer for polydisperse products are:

[0006] lack of optimized pressure distribution in the filtration zone due to the constant pitch and height of the screw flights, which reduces the efficiency of dewatering polydisperse media;

[0007] insufficient intensification of shear and compressive loads on the product as it moves through the filter chamber;

[0008] low adaptation of the design to a wide granulometric composition (polydispersity) of the source material;

[0009] increased energy consumption due to the lack of gradient compaction of the product;

[0010] Limited control over the filtration process due to the shape of the holes in the lower part of the filter chamber.

[0011] The technical objective of the utility model is to increase the degree of mechanical dehydration and drying efficiency, reduce energy costs, expand the technological capabilities of processing polydisperse products, increase the uniformity of compaction and filtration of the product, and improve the conditions for filtrate drainage.

[0012] The technical problem is achieved in that in a combined press dryer for polydisperse products, containing a vertical housing, inside which a filter chamber with a hollow porous screw, a squeezing part and a vibration dryer located coaxially directly under the filter chamber and installed with the possibility of vertical reciprocating movement, the larger base of which is directed downwards and with a screw-shaped trough located on its surface, connected to the drive, as well as pipes for feeding the original product, removing the filtrate, coolant and dry product, what is new is that the vertical housing in the upper part has a cylindrical shape, inside which a perforated filter chamber is coaxially placed, in the cavity of which a screw working element is coaxially installed, containing a central shaft smoothly increasing in thickness from top to bottom with screw blades fixed to it,made with a variable decreasing pitch and height along the movement of the material from the loading zone in the upper part of the screw to the unloading zone in its lower part, wherein on the inner surface of the perforated chamber there are counter blades installed on the inner surface of the housing between the turns of the screw blades, and the filter perforated chamber is rigidly connected to the perforated truncated cone of the vibration dryer made of an aluminum alloy with high thermal conductivity, installed with the possibility of reciprocating movement by means of an eccentric mechanism including an eccentric, a connecting rod and a carriage with vertical guides from a common drive shaft connected through a gearbox to the engine, and the lower end part of the filter chamber has conical openings that widen upward, the large bases of which are oriented towards the working cavity of the filter chamber.

[0013] Fig. 1 shows the design of a combined press dryer for polydisperse products.

[0014] The combined press dryer (Fig. 1) contains a vertical body 1, in the upper part of which a perforated filter chamber 2 is located inside. In the cavity of the filter chamber 2, a hollow porous screw 3 is coaxially installed, containing a central shaft 4, smoothly increasing in thickness from top to bottom, and screw blades 5, installed with a variable decreasing pitch and height.

[0015] On the inner surface of filter chamber 2, counter blades 6 are installed between screw blades 5, providing additional shearing action on the product. Beneath filter chamber 2 is a granulating section 7 in the form of conical openings 8, expanding upward, formed in the lower end portion of filter chamber 2.

[0016] Location below is a vibrating dryer 9, formed in the form of a perforated truncated cone 10, on the surface of which a helical trough 11 is located. Vibrating dryer 9 is rigidly connected to filter chamber 2 and is mounted so as to permit reciprocating motion from an eccentric mechanism 12, which includes an eccentric, a connecting rod, and a carriage with vertical guides (not shown). Drive is provided by a common drive shaft 13, connected via a gearbox 14 to an electric motor 15.

[0017] The device is equipped with a feedstock supply pipe 16, a filtrate discharge pipe 17, a coolant supply pipe 18, a spent coolant discharge pipe 19 and a dry product discharge pipe 20.

[0018] The combined press dryer (Fig. 1) operates as follows. A high-moisture polydisperse product is fed through pipe 16 into filter chamber 2, where, under the action of a rotating screw 3 with variable pitch and flight height, the product is gradually compacted and mechanically dehydrated.

[0019] Counter blades 6 provide additional disruption of the material structure and intensify the filtration of the liquid fraction through the perforated side surface of filter chamber 2, which is then removed through pipe 17. This pipe also removes the liquid fraction from the cavity of porous screw 3 via an intermediate drainage system (not shown). The reciprocating motion of counter blades 6 additionally impacts the product in the axial direction, improving both the filtration and granulation properties of the combined press dryer.

[0020] The dehydrated product enters granulation section 7, where it is granulated through conical openings 8 and, as granules with a uniform structure and minimal moisture content, enters vibration dryer 9. The reciprocating motion of the perforated truncated cone 10 and the heat transfer fluid intensively dries any remaining moisture in the granules. The high thermal conductivity of the vibration dryer material improves heat transfer efficiency. The dried product is discharged through outlet 20.

[0021] The advantage of the proposed vibration press dryer for polydisperse products is as follows.

[0022] An increased degree of mechanical dewatering and drying efficiency is ensured by using a screw working element with a variable decreasing pitch and height of the flights, as well as gradient compaction of the product as it moves.

[0023] The presence of counter blades on the inner surface of the filter chamber ensures intensification of shear and compressive loads, destruction of the material structure and improvement of the filtration conditions of the liquid phase.

[0024] The design of the filter holes is cone-shaped and widens towards the top, improving the drainage of filtrate and reducing the likelihood of clogging, which increases the stability of the unit.

[0025] Combining the processes of filtration, pressing, granulation and drying in a single housing, as well as the use of a vibration dryer with reciprocating motion and high thermal conductivity of the material, reduces energy costs, reduces the size and metal consumption of the unit, and expands the technological capabilities for processing polydisperse products with different granulometric compositions.

Claims

A combined press dryer for polydisperse products, comprising a vertical body, in the upper part having a cylindrical shape, inside which a perforated filter chamber with a coaxially located hollow porous screw, a granulating part, located in the lower end part of the perforated filter chamber, and a vibration dryer, located coaxially directly under the perforated filter chamber, in the lower part of which a perforated truncated cone with the possibility of vertical reciprocating movement is located, connected to a drive, the larger base of which is directed downwards, with a helical chute located on its surface, as well as pipes for feeding the original product, removing the filtrate, coolant and dry product, characterized in that the hollow porous screw contains a central shaft, smoothly increasing in thickness from top to bottom, with screw blades fixed to it,made with a variable decreasing pitch and height along the movement of the material from the loading zone in the upper part of the screw to the unloading zone in its lower part, wherein on the inner surface of the filter perforated chamber there are counter blades installed between the turns of the screw blades, and the filter perforated chamber is rigidly connected to the perforated truncated cone of the vibration dryer, made of an aluminum alloy, installed with the possibility of reciprocating movement by means of an eccentric mechanism, including an eccentric, a connecting rod and a carriage with vertical guides from a common drive shaft connected through a gearbox to the engine, and the granulating part is provided with conical openings that widen upward, the large bases of which are oriented towards the working cavity of the filter chamber.

Images