RU2284438C2 - Freezing method and air chamber for rapid food product freezing - Google Patents

Abstract

FIELD: food industry, particularly food freezing.

SUBSTANCE: method involves loading food products in heat-insulated chamber divided into sections; cooling food products with coolant supplied from cooling machine to provide continuous food product cooling; unloading cooled food products from the chamber. The coolant is directed into the first section via pipeline in bottom-top direction and into the second section in top-bottom direction through orifice formed in intermediate partition. Then coolant passes through all sections in zigzag manner, wherein coolant in fed in bottom-top direction via pipeline and in top-bottom direction through orifices created in partitions. The coolant is heated by heat exchange with food products to be cooled. Coolant temperature at chamber exit is close to that of loaded food product. After food product cooling inside the first and the second chambers up to predetermined temperature sectional inner device shell is moved forward towards coolant flow direction to align the first and the second sections with loading-unloading chamber and coolant flow into loading-unloading chamber is blocked. After that coolant flow is directed to discharge pipeline before food product loading-unloading operation termination. Device for above method realization comprises inner shell, which may rotate about vertical axis. Device is provided with sections defined by vertical partitions fixed to inner shell between inner and outer shells so that the partitions may move for equal distances along with inner shell. The partitions are provided with guiding means for tray installation. Each second partition is separated from inner surfaces of lower and upper closures and from outer shell by elastic members so that section pairs are created. Intermediate partition is provided with orifice formed in upper partition part and adapted to provide coolant circulation. Each second section of the pair communicates with pipeline of each first section of next section pair. The trays have latticed bottoms.

EFFECT: increased operational efficiency, reduced power inputs and possibility to use ecologically-friendly matter, namely air, as the coolant.

15 cl, 3 dwg

Description

The invention is intended for use in the food industry with intensive freezing of products.

A known method of cooling food products, providing for their processing with cold air, and an installation providing the implementation of the described method, comprising a refrigeration processing chamber with cooling batteries and ventilation creating intense air movement (Golyand M.M., Malivany B.N. / Refrigeration technological equipment . - M.: Food Industry, 1977, 19-151 p.). The disadvantage of this technological solution is the use of a refrigeration unit, using, as a rule, environmentally hazardous refrigerants (freon, ammonia). The heat transfer mode in this method and cooling device is implemented at a constant, lowest temperature of the cooling batteries and a constantly decreasing temperature of the cooled product. Thermodynamically, such a heat transfer mechanism is less efficient than countercurrent heat transfer. In addition, additional energy is required to drive the fans.

Known refrigeration chamber for food products containing insulated fencing, separated by at least one partition to form autonomous compartments of variable volume. Each compartment has an individual cooling device. The partition is installed with the possibility of movement along the chamber, while sealing the joints is carried out with an elastic material.

The disadvantages of this refrigerating chamber, including the implemented cooling method, are the thermodynamically ineffective heat transfer mechanism and high energy consumption (RU, 2141083, 6 F 25 D 13/00 Dec 2, 1999).

A continuous apparatus is known for freezing products in containers, including a thermally insulated chamber with air coolers and a fan, disks located on the shaft in the chamber having carriers for containers with the product and through cutouts mounted on their sides. The main disadvantages of this apparatus, including the cooling method on which it is built, are inefficient heat transfer and significant energy consumption, as in the previous examples. (No. 159549, 25.1.1963, F 25 D 13/02).

This patent is the closest relative to the claimed group of inventions.

The present invention aims to achieve a technical result, which consists in increasing the efficiency of the camera, reducing energy consumption and using environmentally friendly air as a working refrigerant.

The technical result, which consists in eliminating these shortcomings in the method of freezing food products, including loading them into a heat-insulated chamber with sections, cooling products with refrigerant from the refrigeration machine with continuous cooling, unloading the cooled products, is achieved by directing the refrigerant into the first section through the pipeline from below , into the second section - from above through an opening in the intermediate partition, then through all sections - in a zigzag fashion; from the bottom through the pipeline, from above through the hole in the partitions, the refrigerant is heated by heat exchange with the cooled products and removed from the chamber with a temperature close to the temperature of the loaded product, through the waste pipes, after cooling the products in the first and second sections to the required temperature, move the inner shell with sections towards the movement of the refrigerant before combining the first and second sections with the loading and unloading compartment, cut off the flow of refrigerant into this compartment and direct it to the waste pipes the drive until the end of the unloading-loading of products.

The refrigerant insulated in the heat-insulated chamber is directed by the return flow to the refrigeration machine, while the shut-off elements on the discharge pipe are closed.

The technical result, which consists in eliminating these shortcomings in the air chamber of intensive freezing of food products, including a thermally insulated chamber with an inner and outer shell, evenly spaced sections between them, food trays, doors in the chamber on the outer shell for loading and unloading products, pipelines, is achieved the fact that the inner shell is made to rotate relative to the vertical axis, the sections are formed by vertical partitions, rigidly mounted on the inside The inner shell between the inner and outer shells can be moved together with the inner shell at equal intervals, the partitions are equipped with guides for installing trays, and each second is separated from the inner surfaces of the lower and upper covers and the outer shell using elastic elements to form a pair of sections in which the inner the partition is made with a hole in the upper part for advancing the refrigerant, each second section of the pair is connected by a pipeline to each first section of the next pair of sections second, in addition, the trays are made with slatted floor.

The desired effect is achieved by the fact that a cold gas stream flows sequentially into the sections, takes away heat from the cooled product and leaves the last section with a temperature equal to the temperature of the loaded product. After the products are cooled in the first and second sections to the required temperature, the apparatus rotates and these sections enter the loading and unloading compartment and are installed opposite the door to remove the chilled product and install trays with new products. The design feature of the compartments is their separation into pairs, which ensure the movement of the cold gas flow from bottom to top in the first section and through the hole at the top in the partition separating these sections, and from top to bottom in the second section, which in turn provides cooling for the next third section after turning the device also in the direction from the bottom up and down, which allows the implementation of effective countercurrent heat transfer.

The intensive freezing air chamber shown in Figs. 1, 2 is a heat-insulated chamber (1) with thermal insulation (2), with fixed external shell (3), upper (4) and lower (5) covers, with rotating on the vertical axis (22) with the inner shell (6). Partitions (7) are rigidly mounted on the inner shell, which form, together with the surfaces of the upper and lower covers and the inner surface of the outer shell, sections for installing trays (8) with products and their cooling. The partitions forming the sections are sealed off from the surfaces of the upper and lower covers and from the outer shell using elastic elements (9) and have guides for installing trays (23). Moreover, each even partition separating each pair of sections has an opening (10) in its upper part for advancing the refrigerant, and each second section is connected to each first section of the next pair by pipelines (11). The chamber has a loading and unloading compartment (12) into which two sections are placed and into which products are loaded and unloaded through the doors (13) in the outer shell. The chamber is equipped with a refrigerant supply pipe (14) and waste pipelines that exit from the loading and unloading compartment and from the section adjacent to the compartment (15, 16); shut-off bodies are installed on the discharge pipelines (17, 18). In order to return the refrigerant heated in the chamber to the return flow of the air cooler, the chamber has a pipeline (19) and a shut-off element (20) installed on it. The trays on which the products are placed have a trellised bottom (21), which allows the passage of refrigerant.

The air chamber operates as follows. Products are placed on trays (8) and installed along the guides (23) in each section of the chamber. After this operation is completed, the door (13) is hermetically closed and through the pipeline (14) refrigerant is supplied to the chamber with a temperature below the product cooling temperature of 10-20 ° C and with a flow rate ensuring the air velocity in sections V = 6 ÷ 10 m / s, which passes in the first section from the bottom up, then through the hole in the upper part of the partition (10) separating the sections of the first pair, enters the second section and passes through it from top to bottom, then the refrigerant through the pipeline (11) enters the first section of the next pair of sections and passes through it from below up, as in the first section of the first pair. The refrigerant passes through all sections, gradually being heated by the heat of the product being cooled, and is removed from the chamber through a pipeline (15) and an open shut-off element (17). In this case, the locking element (18) is closed. After reaching the desired temperature for cooling the products in the first and second sections, the inner shell together with the sections makes a two-step turn, by the distance occupied by two sections, which are moved to the loading and unloading compartment. Next, the shut-off element (17) closes and at the same time opens the shut-off element (18) on the discharge pipe (16). This operation allows, without stopping the cooling of products in all compartments of the chamber, open the door to the loading and unloading compartment and unload the chilled product and load a new product. After loading a new product, the door (13) is hermetically closed, the shut-off element (18) closes and the shut-off element (17) opens, which ensures cooling of the new product in the loading and unloading compartment.

The analysis of the prior art by the applicants, including a search by patent research sources of information, made it possible to establish that the applicant did not find an analogue characterized by features identical to all the essential features of the claimed invention. Therefore, the claimed invention meets the criterion of "novelty" under applicable law.

A comparison of the essential features of the proposed and known solutions gives reason to believe that the proposed technical solution meets the criteria of "Inventive step" and "Industrial applicability".

Thus, the application of the proposed freezing method and the intensive freezing air apparatus increases the efficiency of the cooling process by reducing the loss of cold associated with the exclusion of the heat exchanger, ventilation air circulation systems from the apparatus, and ensuring countercurrent heat exchange.

Claims (3)

1. A method of freezing food products, including loading them into a thermally insulated chamber with sections, cooling the products with refrigerant from the chiller with continuous cooling, unloading the chilled products, characterized in that the refrigerant is sent to the first section through the pipeline from below, into the second section from above through the hole in the intermediate partition, then through all sections is zigzag; from the bottom - through the pipeline, from above - through the hole in the partitions, the refrigerant is heated by heat exchange with cooled products and removed from the chamber with a temperature close to the temperature of the loaded product through the waste pipelines, after cooling the products in the first and second sections to the required temperature, move the inner shell with sections towards the movement of the refrigerant before combining the first and second sections with the loading and unloading compartment, cut off the flow of refrigerant into this compartment and direct it to the waste pipe oprovod until after unloading-loading products. 2. The method according to claim 1, characterized in that the refrigerant heated in the heat-insulated chamber is directed by the return flow to the refrigeration machine, while the shut-off elements on the discharge pipe are closed. 3. An air chamber for intensive freezing of food products, including a thermally insulated chamber with an inner and outer shell, sections evenly spaced between them, food trays, doors in the chamber on the outer shell for loading and unloading products, pipelines, characterized in that the inner shell is made with the possibility of rotation relative to the vertical axis, the sections are formed by vertical partitions rigidly mounted on the inner shell between the inner and outer shells with the possibility of ne the premises together with the inner shell at equal intervals, the partitions are equipped with guides for installing trays and each second is separated from the inner surfaces of the lower and upper covers and the outer shell with elastic elements to form a pair of sections in which the inner partition is made with an opening in the upper part for promotion refrigerant, every second section of the pair is connected by a pipeline to each first section of the next pair of sections, in addition, the trays are made with a trellised bottom.

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