SU938892A2 - Rotary film apparatus - Google Patents

Description

(54) ROTARY FILM MACHINE

The invention relates to the design of a rotary film apparatus and can be used in the food and chemical industries for heat and mass transfer processes in the processing of heat sensitive products, for example, when whey is thickened to b5% solids in the production of milk sugar and protein-carbohydrate concentrate.

According to the main auth. If 793532 a device is known that comprises a vertical chamber formed by two parallel cylindrical surfaces, rotors mounted coaxially with the respective cylindrical surfaces of the chamber, heat exchanger jackets, nozzles for supplying and discharging the processed product and heat carrier, as well as a suction nozzle for evaporating vapors.

In this apparatus, due to the sharp increase, continuous and

radical renewal of the contact surface of the phases during the spraying of the film with scrapers and the transformation of the spray again into the film; the intensity of heat and mass transfer processes is increased by a factor of 2-3 compared with traditional rotary film apparatuses such as Luva and Samboy 1.

The disadvantages of the known apparatus are the need to synchronize the rotation of the rotors; the inability to use the most versatile rotor devices - rotors with hinged scrapers.

The purpose of the invention is to simplify the design and increase reliability in operation.

Claims (1)

This goal is achieved by the fact that in the rotor apparatus the cylindrical surfaces of the chamber contact with each other to form edges in such a way that one of the edges lies on the line connecting the centers of the rotors and is formed by intersecting arcs whose curvature radius is 1.05-1 1 from the radius of the rotor, and the other edge is formed respectively by arcs 1.2-1.3 from the radius of the rotor at the radial location of the scrapers. Such an arrangement of the chamber ensures that in the space between the edges the articulated scrapers of adjacent rotors take a radial position under the action of centrifugal force, but the circular trajectories of the ends of the scrapers do not intersect each other, which makes it possible to drive the rotors according to the simplest scheme - electric motors. In addition, in the region of the edges, the scraper rotors act on the film of the product with an attack angle of about 90, i.e. A rotor with hinged scrapers at the edges is transformed into a rotor with a matic (oscillating) scrapers, characterized by high values of heat and mass transfer coefficients during deep evaporation of the solution down to the dry residue. The geometric shape of the housing is also due to the need to create conditions for the smooth release of the scrapers from the edge when spraying the film, as well as for the shock-free entry of the scrapers to the opposite edge when converting the spray torch back into the film flow. FIG. 1 shows a rotary film apparatus, a longitudinal section; in fig. 2 shows a section A-A in FIG. in fig. 3 shows a section BB in FIG. The device includes a vertical chamber in the form of cylindrical surfaces 1, made with a gap (a gap along the perimeter and inseparably interconnected by welding with the formation of edges 2 and 3, a heat exchange jacket j, rotors in the form of shafts 5 and 6, on which disks 7 are fixed with hinged scrapers 8, separation space 9, nozzles 10 and 11 for supplying and discharging the product, respectively, steam suction fitting 12, nozzles 13 and 1 for heat transfer inlet and outlet. The rotors are rotated from individual drives 15. The edge 2 is located on the line connecting the centers of the rotors and formed by the intersection of arcs, the radius of curvature of which is 1.051, 1 from the rotor radius, and the edge 3 is formed by respectively arcs 1.21, 3 from the rotor radius. The distance between the centers of adjacent rotors is equal to the maximum rotor diameter when the scrapers are radially positioned. The rotor film apparatus operates as follows. The solution (suspension), for example, partially condensed milk whey, is continuously fed through fitting 10 to the machine between edges 2 and 3 on rotary joint scrapers 8. Rast The thief is caught by the scrapers 8 and distributed by them over the heat transfer surface in the form of a uniform film. When the film moves along the heat transfer surface under conditions of intensive mixing with scrapers 8, is accompanied by cyclic spraying from the edge 2 and spray conversion again into the film flow on the opposite edge 3, high-intensity heat and mass transfer occurs as the evaporation surface increases by several orders of magnitude with the free surface of the film and, moreover, the evaporation surface is continuously and radically renewed due to the mechanical spraying of the film and practically and instant coalescence (aggregation) of droplets (product particles). Condensed solution at port F is continuously removed from the apparatus for further processing. The proposed rotor film apparatus, having a high intensity of heat and mass transfer processes, makes it possible to use in it the most versatile of the rotor devices - rotors with hinged scrapers. The proposed rotary apparatus in comparison with the known is simpler to manufacture and install, has a high operational reliability. Since the angle of attack of the scraper almost constantly varies along the entire perimeter of the chamber from S-60 to 90, the scraper undergoes inevitable vibrations, which exclude the possibility of jamming of the scraper hinges, i.e. Provides reliable conditions for the processing of crystallizing, polymerizing and corrosive products. Claims of the invention Rotary film apparatus according to ed. St. No. 793552, which is also distinguished by the fact that, in order to simplify the design and increase reliability in operation, the cylindrical surfaces are in contact with each other to form edges in such a way that one of the edges lies on the line connecting the centers of the rotors and is formed by the intersection of arcs of curvature 9 1S 2 of which is 05-1.1 from the rotor radius, and the other edge is formed by respectively arcs 1.2-1.3 from the rotor radius. Sources of information taken into account in the examination of I 1. USSR author's certificate N-793552, cl. A 23 C 3/00, 1978.