RU2202934C1 - Toroidal moisture-thermal processing apparatus - Google Patents

Abstract

FIELD: food-processing industry. SUBSTANCE: apparatus has toroidal casing, charging and discharge hoppers, steam pipeline, moisteners, and drive. Casing is inclined in ready product discharge direction and is provided with alternating upper and lower recessed sectors. Casing has sectioned working chambers mounted in guides for movement on spherical wheeled supports and equipped with shock-absorbers fixed on pins. Upper liquid supplying sectors provided with pipelines having nozzles and lower heat-carrier supplying sectors having nozzles are arranged in alternation. Guides positioned in front of discharge hopper are extending in helical path for turning section working chambers relative to axis of annular section of tore and returning to initial position. Apparatus is used for moisture-and-thermal processing of bulk products, in particular, for cooking of groats to obtain cooked and dried groats, as well as for cooking of leguminous crops and vegetables, such as carrot, potato, beet etc. EFFECT: simplified and compact construction, increased versatility of equipment, improved quality of ready product, increased efficiency by expedient use of hydrodynamic product processing mode and heat-carrier potential and by eliminating intermediate transportation operations. 5 dwg

Description

 The invention relates to equipment for the thermal and thermal processing of bulk products and can be used for cooking and drying various types of cereal products, for example, for the production of cooked-dried cereals and legumes, as well as the thermal treatment of carrots, beets, potatoes, etc.

 A known apparatus for cooking and drying rice [US Pat. France 1547726, A 23 L] continuous operation, including a locking device, feeder, conveyor belt, cooking and drying chambers. Cooking is carried out by steam supplied through special nozzles to the product layer. The cooked product is sent to a dryer with two horizontally sequentially installed screws. Drying is carried out by supplying heated air directly to the screws.

This apparatus for cooking and drying has the disadvantages of:
- the implementation of the processes of cooking and drying with different coolants, cooking with steam, drying with air, which significantly reduces the efficiency of using the coolant and heat and mass transfer during product processing due to lower heat transfer coefficients for air compared to steam;
- significant heat loss due to cooling of the product after cooking;
- the implementation of drying in a dense overflowing layer due to the use of screws for drying, which leads to a longer drying time compared to drying under active hydrodynamic conditions of the product layer;
- irrational steam supply for cooking, due to the direction of steam into the product through nozzles located above the conveyor belt, which does not ensure uniform processing of the product layer along the length of the cooking chamber.

 The closest technical solution to the problem to be solved and the achieved effect is the installation of continuous operation for cooking and drying cereals [Zelepuga A. S., Sirotkin G. L., Gulyaev V. N. Installation for cooking cereals at atmospheric pressure and drying in a pulsating fluidized bed .// Canning and vegetable drying industry, 1980, 8], consisting of a cooking apparatus, a conveyor belt and a drying apparatus.

 The cooking apparatus is a tunnel-type housing, on the drums and guides of which a mesh conveyor belt is installed, under which there is a steam chamber with steam-supplying perforated tubes and a discharge pipe of the recirculation duct. Needle agitators are also available. In the apparatus for drying by steps with a height difference, there are three stationary perforated sections of gas distribution grids, separated by gates installed with the possibility of vertical movement, under which hot air is supplied by pulses through the coolant supply device.

This installation has the following disadvantages:
- its productivity is not high enough;
- it does not provide uniform cooking and drying of the product, which reduces the quality of the finished product;
- low efficiency of use of the coolant for drying cereals, due to the non-use of the generated steam during drying of the product;
- significant heat loss due to cooling of the product when it is overloaded into the drying chamber;
- cumbersome installation;
- increased metal consumption of the installation.

 The technical task is to create equipment to improve the quality of the finished product and increase the efficiency of the process due to a more rational use of the hydrodynamic regime of product processing and the energy potential of the coolant, elimination of intermediate transport operations and the creation of a compact universal equipment.

 The technical problem is achieved by the fact that in the proposed toroidal installation for thermal moisture treatment, comprising a housing, loading and unloading bins, a steam line, humidifiers and a drive, the novelty is that the housing is toroidal, located in an inclined plane in the direction of unloading of the finished product with alternating upper and the lower sectors with cuts, contains sectional working chambers mounted in rails with the ability to move on ball wheel bearings and equipped with buffers mounted on axles, etc. and the upper fluid supply sectors, equipped with a pipe with nozzles, and the lower coolant supply sectors, having nozzles, are alternately alternating, and the guides in front of the discharge hopper are made along a helix with the possibility of turning section working chambers relative to the axis of the torus annular section and returning to the initial position .

 The toroidal installation for thermal treatment is presented in the general view (Fig. 1) and drawings of structural elements (Figs. 2, 3, 4, 5).

 The toroidal installation for thermal moisture treatment (figure 1) includes a housing 1, hoppers loading 2 and unloading 3, steam lines 4 and drive 5.

 The housing 1 is made toroidal and is located in an inclined plane, with an inclination towards the discharge side of the finished product (figure 1). The housing is equipped with alternating upper 6 and lower 7 sectors with cutouts. The toroidal sectors 6 and 7, respectively, of the liquid and coolant supply are alternately arranged alternately. After alternating sectors 6 and 7, the casing has a cylindrical section, in which, depending on the type of product being manufactured, not only aging and bringing the product to cooking is possible, but also drying of the product under active hydrodynamic conditions of the bed (fluidized bed, pulsed fluidized bed ) superheated steam. In the housing, sectional working chambers 8 are installed, installed in the guides 9 of the torus surface.

 Sectional working chambers 8 consist of a mesh bottom 10, side walls 11, rear 12 and front 13 partitions, spherical wheel bearings 14 (FIGS. 2 and 3). The front partition 13 has in the upper part an arched visor 15 overlapping from above the arched visor 16 of the rear partition 12 of the subsequent sectional chamber (FIGS. 4 and 5). Sectional working chambers 8 are equipped with shock-absorbing buffers 17 fixed on the axes 18 and rigidly connected to the partitions 12 (Fig. 5). Sectional working chambers 8 are located in the guides 9 with the possibility of movement inside the torus surface of the housing on the spherical wheel bearings 14.

 The upper toroidal sectors 6 are provided with a pipe 19 with humidifiers 20 for supplying a liquid medium (water) (figure 2). In the lower part of the housing from the discharge hopper there is a collector 21 passing through the lower toroidal sectors 7 and cutouts under the upper toroidal sectors 6. The collector 21 in the lower toroidal sectors 7 has a steam distributor 22 with nozzles 23 connected to the steam line 4 for supplying coolant (saturated steam) (Fig. 3).

 The guides 9 in front of the unloading hopper 3 are made along a helical line (the position of points A-A'-A "and B-B'-B") with the possibility of turning sectional working chambers relative to the axis of the annular section of the torus and returning to the starting position (Fig. 4) .

 At the lowest point of the inclined plane of the location of the torus surface of the housing is placed an adjustable drive 5 (Fig. 1) having sprockets 24 on the output shaft located on opposite sides of the side walls of 11 sections (Fig. 4) and configured to lift the sectional working chambers up the torus the housing due to contact with the symmetrical consoles of the axles 18. On the axles 18 are also fixed chain sprockets 25, transmitting rotation to the sprockets 26, providing the rise of the subsequent section.

 Toroidal installation for thermal treatment works as follows.

 The drive is turned on, and the initial product from the loading hopper is fed into the sectional working chambers 8 of the housing 1.

 By changing the speed of rotation of the sprockets 24, a predetermined speed of movement of the sections 8 in the toroidal housing 1 is provided, the intensity of the spillage of particles in the sectional working chambers of the housing and the degree of filling of the working volume of the installation and, consequently, the movement of the processed material.

 The movement of the sections along the guides of the inner surface of the housing is carried out: on the "ascending" branch of the trajectory due to the lifting of the sections by the drive and the "support" of the section by the subsequent moving section; on the “descending” branch due to the gravity of heavier sections with a high humidity product compared to the initial stage of processing on the “ascending” branch of the trajectory.

 The movement of the sections along the guides is associated with rolling friction, which is characterized by a lower coefficient of friction of the kinematic pair and, therefore, resistance when moving the section and the cost of electric drive power.

 To preserve the continuity of movement of the sections, the sprockets 26 come into contact with the corresponding axis of the section at the moment when the previous axis of the section and the teeth of the leading sprockets are in contact 24. Therefore, the teeth, of all drive sprockets and axes of the sections, will be in contact with the load at the same time, which reduces specific load and dimensions of the drive mechanism.

 At the same time, saturated steam is supplied through the pipe from the steam supply line into the housing 1, which, passing through the nozzles 23 of the steam distributor 22 and the holes of the perforated bottoms 10, penetrates the layer of the overflowing product located inside the sectional working chambers of the housing 1.

 Moving to the upper toroidal sector 6, the product particles are processed by a liquid. To do this, water is supplied through a pipeline 19 with humidifiers 20. In this case, there is no steam supply from below the gas distribution grill. The main steam stream is cut off by the end wall of the upper toroidal sector 6 and remains in the lower sector 7. A small part of the steam passes into the gap under the perforated bottom 10 and serves to maintain the thermal effect on the particles of the processed product. With the further movement of the sectional working chamber along the torus surface of the casing, the section moves above the coolant supply sector, and the product layer (for example, cereal) located on the sieve bottom is penetrated from bottom to top by an upward flow of coolant (saturated steam) supplied through nozzles at a given speed corresponding to the desired hydrodynamic regime of the product layer. Moreover, depending on the type of processed product, a steam and water supply mode is set: continuous, periodic, pulsating, etc.

 The end walls of the upper toroidal sectors 6 contribute to the alignment of the product layer in sections, which contributes to its uniform processing and improve the quality of the product. Thus, by changing the flow rate of the coolant and providing oscillated processing of the product with alternating periods of exposure to liquid and steam, they achieve the most rational hydrodynamic regime of the layer and the optimal duration of the process of moisture-heat treatment of the product.

 The design parameters and the presence of cylindrical sections of the toroidal body after the loading hopper and before the unloading hopper, alternating upper 6 and lower 7 sectors of liquid and steam supply are completely determined by the kinetic curve of moisture absorption during moisture-heat treatment of products [Kalashnikov G. V., Ostrikov A.N. Resource-saving technologies of food concentrates. - Voronezh: Voronezh State University, 2001.-355 pp.] And reflect the correspondence to the periods of heating, variable speed and a rational method of moisture and heat treatment of bulk products.

 The housing has sections corresponding to the kinetics of the process of moisture and heat treatment: cylindrical for the heating period, alternating sectors for the variable speed period and again cylindrical for holding and bringing the product to the state of readiness, as well as subsequent drying.

 The oscillatory movement of the sections of the housing 1 due to the damping by buffers of dynamic effects between the sections and the uneven rotation of the drive sprockets contributes to the simultaneous mixing and leveling of the cereal layer, as well as uniform periodic processing of the product particles by the flow of coolant and liquid.

 After the section with alternating sectors 6 and 7 sections with the welded product are sent further to the cylindrical section of the housing for subsequent drying. Drying is carried out by an upward flow of superheated steam directed through the steam line at a speed that ensures the active hydrodynamic regime of the bed (boiling, pulsed fluidized, etc.). Superheated steam has a low superheat temperature and is used after drying, along with evaporated moisture, for cooking products, dampened by the sprayed liquid to a saturation state. Steam passes along a toroidal contour through interconnected gaps in the end walls of sectors 6 and 7.

If drying is not performed in this installation, superheated steam is not supplied and sections with the cooked product are sent for unloading. After the completion of the process of moisture and heat treatment, the sectional working chambers of the housing 1, turning 180 ^o above the discharge hopper 3, return to their original position due to the screw arrangement of the guides of the housing (Fig. 4, the shaded path of the sections A-A'-A "-B-B '-IN").

 The finished product is poured from the inner surface of the sections and then sent to the further technological stage of production.

 The presence of overlapping arched visors of the partitions 12 and 13 of the adjacent sectional working chambers prevents the product from spilling during loading and ensures the continuity of the process.

 The toroidal casing is located in a plane inclined towards the discharge hopper at an angle β (Fig. 1), which exceeds the angle of repose of the finished product, which ensures that particles are completely poured into the discharge hopper.

 However, the most appropriate is the consistent use of a toroidal installation of thermal moisture treatment of continuous operation to perform any combination of technological operations - moistening, cooking, drying, etc., since this eliminates the need for additional handling and transport operations.

 The manifold 21 for supplying steam before and after processing the product with liquid is located inside the housing 1. At the same time, it is located inside the lower toroidal sectors 7, directly near the sieve bottoms, and contacts the upper mountainous sectors 6. This contributes to less heat loss to the environment and thermal efficiency of the process .

The proposed toroidal installation for moisture treatment allows
- achieving uniform moisture and heat treatment of the product due to alternate wetting and steam flow treatment, as well as the use of "soft" temperature and "gentle" modes of product movement while maintaining the maximum particle shape of the processed product;
- improving the quality of the finished product through the use of a rational hydrodynamic regime of the dispersed product layer, reducing clumping of the welded product and preventing the formation of agglomerates of the dispersed material;
- more efficient cleaning of the perforated bottom and unloading of the product through the use of gravitational forces;
- ensuring optimal oscillatory hydration through the use of alternating treatment areas with steam and water;
- increase the productivity of the apparatus due to the consistent execution of any combination of technological operations (moisturizing, cooking, drying, etc.), since this eliminates the need for additional handling and transport operations;
- effective use of the coolant pressure and, consequently, the energy potential to ensure the required hydrodynamics of the process of moisture and heat treatment of the product.

Claims (1)

 A toroidal installation for moisture treatment, including a housing, loading and unloading bins, steam line, humidifiers and a drive, characterized in that the housing is toroidal, located in an inclined plane in the direction of unloading of the finished product with alternating upper and lower sectors with cutouts, contains sectional working chambers mounted in rails with the ability to move on ball wheels and equipped with buffers fixed on the axles, while the upper sectors of the fluid supply, equipped with pipes cable with nozzles, and bottom sectors coolant supply having a nozzle disposed alternately interleaved, the guides are made before the hopper discharging the spiral line, with the working chambers sectional revolution about the axis of the annular section of the torus and the return to the original position.

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