DE1061293B - Training and arrangement of wipers in thin-film evaporators - Google Patents

Description

The invention relates to the design and arrangement of wipers in thin film evaporators, wherein the wipers are arranged concentrically to the agitator axis on agitator rings around pivot pins are so that they are on the vertical, externally heated cylindrical wall, on the inner surface the product runs down from top to bottom, 'grind'.

In all thin-film evaporators of this known type, it is disadvantageous that the evaporation xo Parts of the film can become detached from the wall and evaporate in the form of drops within the Fall down the evaporator body or in the form of very fine droplets or mist from the steam stream into the Capacitor to be taken. With the introduction of the wiper it was possible to wetting the To improve the surface and to make it more difficult to detach the liquid from the wall. Even though through the use of the usual sheet-shaped wipers already a considerable improvement in the Film ratios compared to the simple free-fall evaporator has been achieved, it is still one important task of completely preventing the drops from spraying off, as these should concentrate as much as possible Dilute the residue again or contaminate the distillate.

It has now been found that an improvement in droplet separation occurs when according to the invention The pivot pins of the wiper are so close together that the wiper is louvred, however still at a distance from each other. The wipers can be curved in an arc, see above that the steam flow rising inside the evaporator body is set in rotation by them. at An evaporator with a built-in condenser is prevented by the wipers arranged in the manner of a louvre direct heat radiation from the heated evaporator surface to the cooled condenser surface.

Exemplary embodiments of the subject matter of the invention are shown in the drawing shown schematically. Herein shows

Fig. 1 shows a longitudinal section through the evaporator and

Fig. 2, 3 and 4 show cross-sections through wiper agitators, the wiper blades of which are different Have shapes;

Fig. 5 shows the longitudinal section of an evaporator with built-in condenser and

Fig. 6 shows a cross section through this evaporator.

In Fig. 1 1 means the feed for the liquid to be evaporated, 2 the liquid distributor, 3 the evaporator container, 4 the heating jacket of the evaporator container, 5 the outlet for the non-evaporated residue, 6 the outlet nozzle for the Formation and arrangement of wipers in thin-film evaporators

Applicant:

Paint factories Bayer Aktiengesellschaft, Leverkusen-Bayerwerk

Dipl.-Ing. Rudolf Schneider, Krefeld-Uerdingen,
has been named as the inventor

Steam in communication with the vacuum device (not shown).

On the shaft 7, wipers which are movable around pins 9 are seated in rings 8 fastened concentrically on the shaft 10, which coat the inside of the container 3 and thus distribute the film of liquid running down there. At the end of the shaft there is a z. B. designed as a race 11 sliding surface on the Inner surface of the container slides and ensures that the shaft is centered.

As can be seen in Fig. 2 to 4, the wipers 10 are arranged like a blind so that the on the cylindrical Surface sliding edges of the wiper, seen from the shaft center, behind the pivot point edge of the next following wiper are covered.

By this arrangement it is achieved that drops spraying off the wall with a high degree of certainty detected by the next following wiper and returned to the wall by centrifugal force will.

Fig. 3 shows curved blades, which means more favorable flow conditions for the resulting Obtain steam and at the same time generate a rotation of the steam flow rising in the evaporator will. As a result of the rotation of the steam, any droplets that have been carried away are returned to the heating wall thrown back.

Fig. 4 shows another possible arrangement in which the pivot point 9 of the wiper 10 is not on the The leading edge of the wiper is more towards the center of the wiper, and with the strong rotation of the ascending one Particular importance is attached to the steam column.

The overlapping wipers have particular advantages if they are inside in a manner known per se

■ ^{; iU} ^ 909 577/383

A condenser 12 is arranged in the cylindrical thin-film evaporator (see Figs. 5 and 6). By this arrangement of the wipers creates direct heat radiation from the heated evaporator surface prevents the cooled condenser surface and thus not only the thermal efficiency, but the volume of the evaporator is also increased at the same time.

Although it is in thin film evaporation! louvre-like Internals known, but they serve as capacitor surfaces. Through the blind-like according to the invention arranged circumferential wiper simplifies the evaporator construction with built-in Capacitor; one saves space, thereby increasing the distance between the evaporation surface and the condensate surface can be kept smaller, which is especially good for High vacuum distillation and molecular distillation is beneficial. Due to the closer assembly and the --saving; A special radiation protection makes the construction more economical.

Claims (2)

Patent claims: 1, Design and arrangement of wipers in thin-film evaporators, the wipers being concentric are movably arranged to the agitator axis on agitator rings around pivot pin, so that they on the heated cylindrical wall, on the inner surface of the product from top to bottom runs down, grind, characterized in that the pivot pin (9), the wiper (10), are arranged so close to each other that the wipers (10) are blind-like, but still at a distance each other, cover. 2. Wiper according to claim 1, characterized in that it is curved in an arc shape are. 1 sheet of drawings © 909 577/383 7.59