CS282489A3 - Device for enhancing the purity of steam in multiple-effect evaporators - Google Patents

Description

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In general, the invention relates to a device for improving the purity of steam produced in evaporators, consisting of multistage falling-layer film parks. More specifically, the invention relates to an apparatus for improving the vapor purity of an evaporator in which the vapor-liquid separation is supported by an increased gravitational field.

Evaporators for thickening solutions and slurries are used in a variety of industries such as seawater desalination, water treatment, food production, chemical and pharmaceutical production, pulp and paper production, and metal processing. The evaporators may be used to separate the solvent from the solution, to increase the concentration in the solute solution or to crystallize in the solute solution. A number of evaporator types are used and a large variety of existing design solutions are known. One example is a multistage, descending film-like evaporator, with vertical tubes, according to U.S. Patent No. 4,287,019. Another example is the crystallization kit of US Patent No. 4,329,198. The author of the present invention is the author of both cited inventions.

The aforementioned patent describes an improved multi-stage film evaporator in which separation takes place in a series of separators with increased gravitational forces exerted by rotating circulating wheels.

The latter patent discloses an improved evaporator with forced circulation, using a rotating impeller to push the liquid through a heat exchanger in which the liquid is heated and then returned to the vapor separator in which the impeller rotates, serving simultaneously for separation. liquid from the developing steam when the heated liquid is subjected to reduced pressure.

Increased gravitational forces are exerted on the liquid droplets that can be suspended in the gas phase, which can accelerate their separation from the biphasic mixture. The efficiency of phase separation is increased in the vapor separator with increased gravity. Improved vapor separation of the liquid can be achieved by reducing the volume of the separator vessel compared to the use of conventional velocity-dependent separating devices. The high purity of the vapors generated is also desirable in the vaporization of the liquid by centrifugal movement of the gas-liquid mixture in a rotary path, such as by the action of a foot impeller rotating in a cylindrical or frustoconical vessel as described in the cited patents. However, in the practical application of the separating devices according to the inventive inventions, it has been found that while the separation space can achieve the expected savings on the volume of the separation vessel, however, the degree of evaporation of the liquid is not always as perfect as desired. Thus, for example, when used in a multi-stage film evaporator for recovering salt water from drinking water, the steam to be separated from the brine can typically contain up to 50,000% of total dissolved solids. The condensation of the recovered vapor may be found to contain up to 500% dissolved solids, which may meet drinking water standards, but may not be acceptable for other uses such as steam boiler feed water. The purity of the distilled water can be increased by reducing the evaporation rate, but this leads to a reduction in the cost savings anticipated when using such separation devices. Thus, it is necessary to increase the purity of the steam using rotary separators for vapor-liquid separation in evaporators.

In order to overcome the problems associated with the known evaporation devices, it is an object of the invention to provide a new and improved method and apparatus for separating vapor from a vaporizer working with rotary separators. The aim is to achieve an improved quality of the separated condensate in the rotary separator evaporators. The aim of the invention has been met by providing a device for improving steam purity in multi-stage evaporators, comprising separation separation means, with vertical shaft separators in each separation compartment, and means for supplying vaporized liquid to the lowermost separator in said shaft and for transferring non-vaporized liquid. the liquid from the lowest separator successively into each further separator in the shaft and to remove the evaporated condensed vapor from each separation compartment. In the sense of the invention, each separator comprises a cylindrical vessel, in this vessel a rotating impeller for accelerating the movement of the heated liquid in the vessel in its inner surface and thereby promoting the conversion of a portion of the liquid into steam. Means are provided in the upper portion of the container to form an axially situated outlet orifice of the steam separated from the vaporized liquid. Further provided are means positioned above the impeller and adjacent thereto, preventing movement of the non-vaporized liquid in the vessel towards the axially located vapor outlet. The evaporator also contains means for common rotary drive of the impellers in all rotary separators in the shaft - 4 -

A feature of the separator solution of the present invention is that improved steam condensation is achieved by the method and apparatus in a manner that is readily applicable to existing known evaporation methods and equipment that minimizes complexity and related costs to the least possible extent. An advantage of the device according to the invention is that the separating device is intended for use in a vaporizer that substantially eliminates the contamination of the condensate obtained by entraining droplets of the vaporized liquid.

Further advantages and novel features of the separator device according to the invention will be apparent from the description below. They can be realized and achieved by configurations and combinations thereof according to the following characteristics of useful embodiments.

Means for preventing the movement of the non-vaporized liquid to the vapor outlet of the separating vessel in which the running wheel is located may conveniently be formed by an annular spray ring mounted above the impeller so as to rotate with it. The vapor-tight connection of the spray disc to the self-propelled wheel can be accomplished using impeller blades. An outlet channel of the liquid is expediently provided in the separator vessel, whereby grooves are provided on the upper side of the spinning ring for directing to the outlet channel of the liquid moving to the steam outlet port. Instead of grooves, ribs can be provided on the top of the spray ring. The splash ring attached to the impeller can be replaced by a fixed separator plate, whereby the vapor-tight sealing of the impeller with this separator plate can be achieved by wipers fixed at the ends of the impeller blades. - 5 -

A solid separator plate located above the impeller may have a frustoconical shape of such a inclination that the liquid adhering thereto will flow downwardly to the liquid outlet channel. The separator plate may also be formed by a first generally horizontal portion and a second generally vertical portion facing upwards. and connected to the first horizontal portion so that the non-vaporized liquid can move along the first threat portion and then drop down into the encouraged gravitational field.

In order to achieve the foregoing and other purposes and in accordance with the object of the invention according to the specification and embodiments described herein, the invention is directed to an apparatus and method for achieving high purity steam at the exit of a rotary separator.

It has been found that by arranging the upper part of the separating vessel to prevent the flow of unvaporized liquid into the steam outlet neck, the quality of the evaporated vapor is achieved. The phenomenon believed to be responsible for steam condensate contamination does not therefore consist in separating the liquid from the vapor in the stimulated graining field, but in passing the liquid around the encouraged gravitational field. Particularly in the previously preferred version of such a separation device shown in Figure 3j, the liquid in the separator vessel is apparently sprayed onto the separator coil 69 into the inward zone of the rotating liquid ring, where it is beyond the influence of the stimulated gravitational field exerted by the rotating Since there is a gap to be left between the upper surface of the separating disk and the upper plate of the separating chamber to prevent wear, such a layer of liquid adhering to the upper surface of the separating disk cannot slide down into the rotating field of the circulating 6 wheels. Thus, the liquid layer advancing along this separating disk to the steam outlet neck is encouraged to flow inwardly through the steam to be separated. Therefore, the liquid or salt solution may be entrained to the steam outlet where it eventually becomes a condensate of steam condensate.

The rotary separator according to the invention comprises means for interrupting or preventing the flow of liquid so as to prevent the flow of liquid to the steam outlet port of the separator. In a preferred embodiment, such liquid flow interruption means are formed by an integral annular ring located at the top of the rotary outlet. lučovače. Alternatively, means for sealing the gap between the rotating impeller blades of the separator impeller and a fixed separating disk at the top of the desiccant vessel may be included. Other alternatives are possible, including different geometry of the separator discs designed to promote liquid removal or flow interruption. Although the use of a rotary separator according to the invention is shown in a multi-stage film evaporator with a plurality of such separators in a vertical shaft arrangement, the rotary separator according to the invention is also adaptable to single-stage evaporators.

The device according to the invention will be described in more detail below with reference to embodiments of the invention, with reference to the accompanying drawings, in which: FIG. 1 is a cross-sectional view of a multistage falling-film evaporator with a built-in separation device according to the invention; FIG. 2 is a cross-sectional view of a forced-circulation evaporator, usable as a crystallizer, in which a separator device according to the invention is used in the form of a rotary separator and a steam-liquid pump separator; FIG. US-A-4,287,019; FIG. 4 is a cross-sectional view of a sectional set of rotary separators in a preferred embodiment of the present invention; in a multi-stage separator assembly, a plurality of rotary separators may be used in a shaft arrangement as shown in FIG. Fig. 5 is a bottom plan view taken along line 5-5 of Fig. 4; with a partially cut-off solid separating disc so as to show the construction of the liquid collection means; FIG. 6 is a sectional view of the stationary part of the bottom of the separator taken along line 6-6 of FIG. Fig. 7 is a partial cross-sectional view of the liquid outlet, taken along line 7-7 of FIG. Fig. 8 is a bottom plan view taken along line 8-8 of Fig. 4 showing a rotary separator and a stationary separator body in a preferred embodiment of the invention; Fig. 9 - another embodiment of a rotary separator according to the invention, comprising surface wipers of a solid plate separator for preventing fluid entrainment; FIG. 10 is a cross-sectional view taken along line 10--10 of FIG. FIG. 11 is a cross-sectional view similar to FIG. 4, but showing a third embodiment of a rotary separator according to the invention; FIG. 12 is a cross-sectional view similar to FIG. 4, but showing a fourth embodiment of a rotary separator according to the invention.

The rotary separator according to the invention is designed for use in water parks when thickened solutions or slurries. FIG. 1 shows a typical multistage, descending film evaporator in which a separator device according to the invention is incorporated. Such a vaporizer typically comprises a plurality of substantially 8 vertically disposed heat exchange tubes 7. It further comprises a skirt 2 divided by horizontal baffles 11 forming separate condensing spaces 6 operating at different pressures. It also includes an upper compartment or flooding box 2 from which the vaporized liquid is fed into the tubes 7 through a distributor 6 or through a sifting bowl, spray nozzles or the like, forming a liquid film in each tube. The distributors 6 can be mounted on the upper ends of each tube 7 such that the liquid vaporized therethrough flows into each tube. When flowing downwards through the pipes J, it is heated by the steam being condensed on the outer surface of the tubes 1. The pressures and steam temperatures are gradually increased from the coldest upper condensation chamber 8 to the hottest lower condensation space. The necessary heat for vaporization can be discharged in boiler 2 or in an external steam condensate heater. When heating the steam condensate in boiler 6, the heat generated in the steam is fed to the evaporator by means of a steam conduit 10 and the condensate is returned to the boiler 6 The heated vaporized liquid flowing downwardly through the tubes is collected in the sump 12 and the return line 14 of the first rotary separator 15.

The separators 15 are assembled into a shaft of separating containers arranged one above the other, comprising rotary impellers mounted on a common drive shaft 16 driven by a suitable device, such as an electric motor 17. Liquid entering the lower separator 15 through the riser 14 and into the other. The separators 15 are driven by the rotation of the orbits 15 to the outer walls of the separators. - 9 - 2 χ-vapor is separated in the separators 15-liquid-gas mixture. The steam X to be generated must return from the outer wall of the separator 15 to the steam outlet orifice located at the separator shaft 15 around the common drive shaft 16 " From the steam outlet port, the steam 2 is first dispersed vertically and secondarily in each condensation space dispersed radially. it interfered with the heat of the exchange tube 7 and condensed thereto. From the upper separator 19 of the vertical separator shaft 19, the remaining non-vaporized liquid is drawn off via the conduit 20 through the pump 21, by which it can be discharged through conduit 22 or recycled through conduit 23. The supplied fresh solution containing the solvent and the solids dissolved therein can be introduced into the evaporator via a feed line 24 or 25. Water is the solvent when the sea water evaporates, and the solids dissolved therein are different in the seawater salt present. which are known per se and therefore need not be written down. It should be noted, however, that the rotary separator evaporator according to the invention can also be used for evaporation of other solvent-solute mixtures, having thermodynamic and physical properties suitable for multistage film evaporation. At each stage of the separation device, the separated vapor Xpak on the tubes X condenses and forms a bath lying on the respective partition X, forming the bottom of the respective condensation compartment 4. The condensate obtained from the condensed compartment 8 in the lower part of the evaporator with higher pressure can be transferred from the vaporized fresh solution. through pipes 26 to the lower pressure condensation compartment 4 and therefrom 10 successively similar riser tubes 26 to other condensation compartments 6 with gradually decreasing pressure.

As shown in Fig. 1, the condensate from the uppermost condensation chamber 6 can be discharged through the conduit 28 through the pump 29 with the lowest pressure.

The main object of the invention is to improve the condensation purity or condensate discharge line 28. Excluded from the uppermost condensing space 6, the pump 31 can be drawn off via conduit 30. When the feed water contains a transient hardness, a solution according to U.S. Pat. No. 3,494,836 can be employed, with the vacuum pump 31 returning at least a portion of the carbon dioxide contained in the exclusion line. gas, into the sump 12 from which the carbon dioxide can then pass through the tubes and thus be in contact with the feed water heated in the tubes. The recycling of carbon dioxide in the aforementioned patent helps to minimize or eliminate the possibility of scaling on the tubes.

FIG. 2 depicts one embodiment of a rotary separator according to the invention, using a combination of steam-liquid pumping and separating means in an evaporator or crystallizer, as described in U.S. Pat. No. 4,329,198. It will be appreciated that the rotary separator according to the invention is readily adaptable to other embodiments of the garments described in said patent, wherein only one of the examples is shown in FIG.

FIG. 2 shows a vaporizer in which the flow rate of the vaporized liquid through the heat exchanger tubes takes place in two opposing passages. The outer tubes 40 are formed by about half of all 11 heat exchange tubes in the evaporator and operate with the flow of the evaporated liquid downward. The evaporated liquid is into the tubes42. the rotary impeller 45 is mounted on a drive shaft 41 disposed in the axis of the rotary separator 41. From the outer tubes 40, the outflowing liquid falls into the lower receptacle 43 from which it is sucked upwardly through the inner riser tubes. 44 tubes of heat transfer tubes. From the inner tubes 44, however, the liquid is sucked off by the pumping action of the rotary race 45 into the space of the rotary separator 41 below the impeller 45 · The outer wall of the separation chamber of the rotary separator 41 forms a partition 46 ~. delimited by the rotary surface, is made around the axis of the rotary separator 41 and has a typically cylindrical or frustoconical shape. The gap between the partition 46 and the evaporator outer shell 47 serves as a channel for supplying the outer tubes 40 with the vaporized liquid. A spraying disk 48 according to the invention is positioned close to the upper wall 49 in the upper partirotation separator 41, serving as a means for preventing the flow of liquid radially inwardly to the steam outlet orifice 50, and in particular as a means for preventing the inward movement of the liquid around the upper wall 49 to the outlet neck 50 steam. The other details shown, such as the heating-air inlet and the design used to connect the container to the vapor, as well as details not shown, such as vaporized liquid feed, condensate outlet, or heating medium outlet are known to those skilled in the art and will not be described herein.

Fig. 3 shows a detail of a prior art rotary separator as described in US Patent No. 4,287,019;

This separator is formed by a stationary substantially cylindrical container 12, bottom closed, except one or more fluid inlets 61 and a sealed bearing 62 of a common drive shaft 63. The rotary impeller 64 is mounted on and rotates with the shaft 63. 65 and from the blades 66, the impeller 64 exerts a rotary movement of the vaporized liquid and the centrifugal force exerted by it, drives the vaporized liquid onto the inner wall of the vessel 60 where the vapor-liquid interface 67 is formed. The steam is discharged through the orifice 68 from which it can freely escape into the condensation chamber 6 according to FIG. The foam separator plate 69, dimensionally adapted to the desired performance of the separator, provides a means for allowing substantially only liquid to escape through the gap between the outer periphery of the separator plate 69 and the inner wall of the vessel 60. Evaporation of the residual liquid is collected in the annular gap 70 by the superfluous through plate 69 and with one or more throats 71 introduced into another separator or discharged from the system. 4 is a partial cross-sectional view of a rotary separator set arranged vertically in a shaft above and arranged in a preferred embodiment of the invention. The separating separator consists of a stationary, substantially cylindrical container 80, bottom closed, except one or more flow-through sleeves 81 and a sealed bearing 82 of the common shaft 83. The shafts 83 are fixedly mounted and rotatable impeller 84 is rotated with it. from a rotary deflector 85, a bladder 86 and a splash plate 87 «mounted on the upper portion of the bladder 86. When the impeller 84 actuates the vaporized fluid-rotating motion, the centrifugal force thus generated drives the vaporized liquid onto the inner wall of the vessel 80. the outlet channel 88 of the liquid. The liquid to be discharged is diffused through the diffuser pads 89 inwardly into the swirling motion and is introduced into one or more fluid outlet ports 81 connected to the next separating stage. These fluid outlet orifices 81 are more readily apparent from FIG. Under the diffuser pads 89, a rigid separator plate 21 is provided to prevent return from the effluent separator by forming a fluid conduit together with the diffuser blades 89. The sealing between the separating stages is achieved by the intermediate sealing O-rings 92. The connection of the separation stages is ensured by the molded elastomeric annular seals 93, which simultaneously serve to seal the intermezzo between the separator vessels 80 and the horizontal baffles 1 as shown in FIG. .1.

The separated vapor must first be moved outward under the deflector, whereupon it can be separated from the liquid near the vessel wall 80. It then has to flow back to the axis of the separator by a quasi-axial outlet outlet 94. From there, the steam is then redirected substantially horizontally to flow into the condensation space between the separators.

4, it is possible to understand the purpose of the invention correctly. The rotary impeller 84 has been supplemented with the sprayer plate 87, which is virtually an annular cover of the impeller 84, as compared to the original embodiment of FIG. 3. This cover has an axially circular opening with a diameter corresponding to the substantially outer diameter of the steam outlet orifice 94 a rotary separator, wherein the outer diameter of the spray plate 82 extends approximately to the outer edges of the impeller blades 86. More specifically, this outer diameter of the spout plate 87 must define a circumferential gap for the liquid outlet relative to the 14th upper inner periphery of the end portion of the sidewall of the container 80, such that the annular gap between the wall of the separation container 80 and the spout plate 87 is such that only the liquid remaining after the vapor separation could pass through and the liquid vapor was not allowed to escape from the vapor separator through the outlet channel 88 of the liquid.

To illustrate how the steam-liquid separation in the separator is improved by the novel stripping plate 87 of the present invention, an example is given. With the use of the original embodiment as described in U.S. Pat. No. 4,287,019, self-gravity separators have been produced and assembled substantially as shown in FIG.

Of the 24 separators, a vertical shaft was assembled, which was then operated in a multi-stage film evaporator with a nominal output of about 19,000 liters per day, as described in this patent file. After commissioning of the kit and after stabilization of its operation, condensate of about 750% purity was continuously produced. Various modes of operation have been tried to reduce the solids dissolved in the condensate and thereby increase its purity. One of them was to reduce the nominal evaporator output from the original 19,000 liters per day to 15,000 liters per day. As a result, the impurity content of the condensate was reduced from 750% to 300%. However, since the reduction of the evaporator's nominal output is economically undesirable, a different solution was sought.

They have been assembled into a shaft vertical co-rotating separator according to a preferred embodiment of the invention and these have been incorporated into the same evaporator as in the previous case. These improved rotary separators were then tested under operating conditions substantially similar to the operating conditions during the previous tests. When the new rotary separators were transported, the content of dissolved solids in the steam condensate was detected at a evaporation capacity of 19.000 liters per day. about 80 # 0.

FIG. 5 is a bottom view of the separator of FIG. The axle shows the rotary shaft 83 and its tight fit 92. The outlet neck of the steam 94 is formed by an annular passage in the separator axis. An annular separator plate 91 extends radially outwardly of the steam outlet orifice 94. The gap between the separator plate 91 and the wall of the separator vessel 80 must be selected in such a way that it can penetrate upwardly into the liquid outlet duct 88 thus formed. liquid. After passing through the outlet channel 88, the liquid diffuser blades 89 are directed into the swirling motion toward the fluid outlet ports 81 connected to the next upper separation stage. 5, it is necessary to direct the liquid outwardly to the vessel 80 while directing the pure steam to the steam outlet 94 of the steam for efficient steam-liquid separation.

Figure 6 is a plan view of the stationary bottom of the separator of Figure 4, with the outlet ports 81 of the liquid. Referring back to FIG. 5, it is apparent that the liquid is directed upwardly through the diffuser blades 69 into the outlet orifices 81 so as to extend into the lower portion of the subsequent separator. Figure 6 also shows an axially disposed rotary shaft 83 with its seat 82.

Fig. 7 is a cross-sectional view of an outlet outlet 81 of the fluid, showing at the same time how the lateral 16 diffuser vanes 81 'of the fluid are discharged from the outlet conduit 88 into the outlet ports 81 of the fluid.

Fig. 8 shows a bottom view of the rotary separator with the rotary wheel 84 in the preferred embodiment of the invention shown in Fig. 4. Here, the separator vessel 80, the rotating shaft 83 and its housing 82 are visible. The steam must pass through the blades 86 the impeller 84 and then to the steam outlet. An annular splash plate S1 is mounted above the blades 86 of the impeller 84 so as to co-rotate them together. To achieve the purpose of the invention, there is no gap between the top of the blades 86 and the rotating plate 87 rotating with them. As will be appreciated, the fluid seeking to move the steam to the steam outlet orifice 94 is captured by the rotating pads 86 or may impinge on the splash plate 87. In both cases, these liquid droplets are then accelerated towards the wall of the separator vessel 80. Hence, by using the splash plate 87, the accumulation of liquid in the upper part of the separator is prevented and the liquid trying to escape is forced to bump the blades 87 or onto the splash plate 87 and thereby accelerate to the liquid outlet duct 88. As indicated by the dashed line, grooves 105 'are provided on the upper side of the splash plate 87. serving to direct all the liquid trying to escape between the rotary plate 81 and the rigid separator plate 91 of FIG. 4 so that the liquid returns to the liquid outlet channel 88. The ridges provided in place of the grooves 105na of the separating screen 87 can serve the same purpose.

Fig. 9 shows a variant of the embodiment according to the invention as seen from above on a rotary impeller assembly 8. The impellers 86 of the impeller 84 are provided with a wiper strip 130 associated therewith. During rotation of the impeller 84 together with the shaft 83, the wiper blades 130 seal the gap between the blades 86 and the upper fixed separator plate 91. In this way, the elastic wiper blade 130 provides a serviceable seal. This embodiment allows for the omission of the rotary plate 8. but is less suitable than the preferred embodiment of FIGS. 4 and 8 with the rotary sip plate SX " Thus, when using this embodiment, a selection of materials for the production of the wiper blades 130 and the solid separator plate 21 is necessary.

Fig. 10 is a partial cross-sectional view of the wiper blade 130 of Fig. 9. The wiper blades 130 attached to the impeller blades 86 by coupling means 131 wipe the fluid from the bottom surface of the solid separator plate 91.

FIG. 11 shows a third variant of the embodiment of the shafts according to the invention, similar to FIG. Here, the separator plate 100 is designed to be inclined at an angle to the axial outlet orifice 94 and generally has a frustoconical shape. It is also apparent here that the lower edge of the steam outlet orifice 94 extends downwardly beneath the inner edge of the conical ring forming a rigid separator plate 100. Thus, inwardly toward the outlet orifice 94 of the vaporized liquid, it is prevented by the gravitational effect from further movement. That by its action all the liquid of the lower surface of the separator plate 100 is pulled back down to the liquid outlet channel 88. When the liquid moves to the obstruction at the inner edge of the solid separator plate 100 formed by the elongated outlet orifice 94, it drips downward on the impeller 84 and is accelerated therefrom towards the inner wall of the separator vessel 80 . 18

FIG. 12 shows another embodiment variant of the separator shaft according to the invention, again similar to that of FIG. 4. Here, the liquid seeking to move to the axis of the rotary separator so as to escape through the steam outlet orifice 94 achieves its centripetal movement along the fixed direction. a 100-meter separator plate in which it no longer has an additional surface to adhere to as it moves. Thus, at the edge 111 of the separator plate 110, the liquid drips vertically downward to the impeller blades 84 and throws them back onto the inner wall 112 of the separator vessel 80.

The device according to the invention can be carried out in other variants without departing from the main characteristics of the invention. The illustrated and described embodiments are therefore to be considered as merely indicative of non-limiting embodiments in all respects. The object of the invention is defined by the subject matter of the invention and not by the description of the embodiments given. Thus, all changes and modifications not intended to be within the scope of the subject matter of the invention are to be construed as being incorporated herein by reference.

Claims (7)

.................................................. ............ d * ?. "..... Wctf '' -, 9- PV 2824-23 PATENT CLAIMS 1 · A device for improving steam purity in multistage evaporators containing separation means from separating, with a vertical shaft of rotary separators in each separation compartment, means for supplying vaporized liquid to the lowest separator in said shaft and for transferring the non-evaporated liquid from the lowest separator to each further separator in the shaft and for venting condensed condensate vapor from each separation compartment, characterized in that each rotary separator comprises a cylindrical vessel (80), in this vessel (80) a rotating impeller (84) to accelerate the movement of the heated liquid in the vessel (80) to its internal surface and thereby promoting the conversion of a portion of the liquid to vapor, and means at the top a vessel (80) forming an axially disposed outlet orifice (94) of the vaporized liquid in the vessel (80) as well as means (86,87) positioned above the impeller (84) and adjacent and preventing movement of the non-vaporized liquid in the vessel (80) towards the ossified outlet orifice (94) through the pores, the evaporator further comprising means (16, 17) for a common rotary drive of the impellers (84) in all rotary separators in the shaft. 2. Apparatus according to claim 1, characterized in that the means for preventing the movement of the non-vaporized liquid to the steam outlet (94) of the vessel (80) in which the impeller (84) is located are formed by an annular spin ring. (87) »attached to the top of the impeller (84) so as to rotate with the impeller (84) together. 20 3. An apparatus according to claim 2, wherein the means for vapor-tight connection of the ring (87) to the impeller (84) is formed by vanes (86). 4. Apparatus according to claim 2, characterized in that the separator vessel (80) is provided with a liquid outlet duct (88), wherein grooves (105) for directing to the outlet duct (88) are provided on the upper side of the spout ring (87). / liquids moving to the outlet orifice (94) of the vapor. 5. Apparatus according to claim 2 or 4, characterized in that the separator (80) is provided with a liquid outlet duct (88), wherein ribs for non-directional discharge to the outlet duct (88) of the capillary are provided on the top of the spout ring (87). moving to the outlet orifice / 94 / steam. 6. Apparatus according to claim 1, characterized in that the means for preventing the movement of liquid to the outlet orifice (94) of the vessel (80), in which the impeller (84) is located, are formed by wipers (130). mounted at the ends of the impellers (86) of the impeller (84) so as to co-rotate with it and to be in direct contact with the solid separating plate (91). 7. Apparatus as claimed in claim 1, characterized in that each separator receptacle (80) is provided with a liquid outlet duct (88) and means for preventing liquid from moving towards the outlet orifice (94) of the vessel (80). /, in which the impeller (84) is located, comprise a rigid frusto-conical separating plate (100) disposed in the container (80) of the separator above the impeller (84) and shaped to adhere to the separator plate (100) the liquid has flowed down to the outlet channel (88) of the liquid. 21 δ. 4. Apparatus as claimed in claim 1, wherein the means for preventing fluid from flowing to the outlet orifice of the vapor of the vessel in which the impeller is located comprise a solid separator plate formed by the first generally horizon. and the second generally vertical upward portion with the first horizontal portion coupled such that the non-evaporated liquid may move through the first horizontal portion and then downwardly. Representative: Λ Z 28732¼.8.1989