Title of Invention

A DEVICE AND METHOD FOR ATOMIZING LIQUIDS

Abstract

A device for atomizing liquids containing a rotatable hollow cylinder for the reception of the liquid to be atomized and a drive for the rotation of the hollow cylinder is provided. The cylinder casing has a plurality of circular hole-type nozzles. The cylinder is closed at its lower end and has an opening at its upper end for the delivery of the liquid to be atomized as well as optionally a feed conduit for the liquid to be atomized, with the feed conduit being rotatable with the cylinder, its longitudinal axis coinciding with the axis of rotation of the cylinder and its end being directed close to the cylinder floor of the cylinder mantle.

Full Text

The invention relates to a device for atomizing liquids and a method for spray cooling of a liquid, said liquid being atomized. The invention also relates to a method for atomizing, spray cooling, and spray drying of liquids using a device of the kind referred to above. The invention fiirther relates to the use of a device of the kind referred to above for the production of powders from solutions or dispersions, preferably from emulsions. A device of the type referred to above is described in the publication of P. Schmid "Auslegung rotierender poroser Zerstaubungskorper', Verfahrenstechnik 8 (1974) No. 7. This publication provides a basic description of the utilization of a hollow cylinder with a plurality of circular hole-type nozzles. BACKGROUND OF INVENTION Document US 6 098 895 discloses a process and device for atomizing liquids. The liquid to be atomized is uniformly sprayed on the inner surface of a hollow rotating cylinder, for example by means of one central fluid-nozzle. Furthermore, the liquid leaves the cylinder through the bores 5 in the wall 1. The document US 6,651,898 relates to a device for atomizing liquids which has a) a rotatable apparatus for the reception of liquids to be atomized, the apparatus is defined by a cylinder having an interior chamber that runs the length of the cylinder with an internal diameter of about 10 to about 25 millimeters, the cylinder has an upper and end with an opening into the interior chamber, which opening is adapted to receive liquids to be atomized, the cylinder has a closed lower end that terminates with a floor, the outer surface of the cylinder is defined by an outer casing having a plurality of circular hole-type nozzles extending up about 20 to about 120 millimeters from the lower end of the cylinder in an axial direction, the hole-type nozzles are in fluid communication with the interior chamber for introducing the liquid to be atomized into the nozzles; and b) a drive operably connected to the cylinder for rotating the hollow cylinder. A method of spray cooling a liquid using the device of the invention, and a method of producing powders from solutions, dispersions, emulsions, or melts are also provided. The document EP 1186348discloses a device for atomizing liquids, which device comprises a rotatable hollow cylinder (11) for the reception of the liquid to be atomized, and a drive (12) for the rotation of the hollow cylinder (11), with the hollow cylinder being closed at its lower end with a bottom (13) and having an opening (15) at its upper end, and its casing (16) having a plurality of circular hole-type nozzles (18) for the output of liquids to be atomized, the device being characterized in that (a) the hollow cylinder (11) has a diameter which is in the range of from 10 to 25 millimeters, and (b) the surface of the cylinder casing (16), which has the circular hole type nozzles (18), extends in the axial direction over a length in the range of from 20 to 120 millimeter. The problem to be solved by the present invention is the provision of a device of the type set forth above with which a narrowO droplet size NS /12.07.2001 distribution can be achieved, whereby the average droplet size during the spraying should be in a range of from 50 to 500 micrometer, preferably in a range from 100 to 350 micrometer. Moreover, it is a fundamental object within the scope of the present invention to provide a device of the type set forth above with which technically desirable throughputs during the process of atomizing liquids can be obtained and which thereby should operate with low wear. The structure and the dimensions of the hollow cylinder and of the circular hole-type nozzles in its casing should be selected in such a way that a uniform distribution of the liquid and its temperature in the aforementioned circular hole-type nozzles is obtained and that the circular hole-type, nozzles have a negligible tendency to get clogged. Furthermore, the hollow cylinder of the present invention should be easy to mount and dismount and the cleaning of the hollow cylinder as well as of the circular hole-type nozzles should be easy. A further object of the present invention is the provision of a method for atomizing, spray cooling, or spray drying of liquids with a device in accordance with the invention. As used herein, the term 'liquid includes solutions, especially aqueous solutions, dispersions and emulsions of active substances as well as melts, e.g., fat melts, optionally containing active substances. Examples of active substances are fat-soluble vitamins, such as, e.g., vitamin A, E, D, or K, carotenoids, such as, e.g., p-carotene, zeaxanthin, lutein, or astaxanthin, fat - or water-soluble pharmaceutically active substances, as well as water soluble vitamins, such as, e.g., vitamin C and the B vitamins. The advantages of a device according to the present invention are as follows: - it facilitates the generation of a laminar thread-like disintegration of the liquid to be atomized thereby achieving a narrow droplet size distribution, with the average droplet size during the spraying being in a range of 50 to 500 micrometer, preferably in a range of 100 to 350 micrometer, - a very compact construction of the device for atomizing liquids due to a very simple structure, relatively small dimensions and the low weight of the hollow cylinder, - a uniform distribution of the liquid and its temperature in the hollow cylinder and in the circular hole-type nozzles in the cylinder casing, by which means obstruction by drying or gelling processes and thereby clogging of the circular hole-type nozzles is prevented, - a very low-wear operation which is achieved by the relatively low flow velocities in the borings of the circular hole-type nozzles of the hollow cylinder, - considerable less energy is required for the rotation drive of the hollow cylinder compared to the energy required by conventional atomizing devices, and - it is optimally suitable for relatively small liquid throughputs. In a preferred embodiment the hollow cylinder is screw-mounted on a co-rotating hollow shaft which serves for the feed of the liquid to be atomized into the hollow cylinder. The hollow cylinder can therefore be mounted and dismounted with little effort, which reduces the expenditure of time for maintenance procedures. By this means and by the very simple structure as well as the low wall thickness of the hollow cylinder, the hollow cylinder as well as the circular hole-type nozzles are easy to clean. By the relatively little additional expenditure for the feed conduit, a uniform distribution of the liquid and its temperature in the hollow cylinder and a uniform distribution of the liquid in the circular hole-type nozzles of the hollow cylinders casing are advantageously achieved despite the optionally larger dimensions of the hollow cylinder. By a method in accordance with claim 30, a very low clogging tendency of the circular hole-type nozzles as defined in the present invention is achieved. BRIEF DESCRIPTION OF THE FIGURES Working examples of the invention are described hereinafter on the basis of the accompanying Figures. Fig. 1 shows a device in accordance with the present invention for atomizing liquids, in which device a hollow cylinder in accordance with Fig. 2 or an arrangement of hollow cylinder 21 with feed conduit 31 in accordance with Fig. 9 can be used, Fig. 2 shows a schematic representation of a cross section of a first embodiment 11 of the hollow cylinder of a device in accordance with the present invention, Fig. 3 shows an enlarged representation of a side view of segment E in Fig. 2, Fig. 4 shows an enlarged representation of a small part of a cross section of the cylinder casing 16 in Fig. 2, Fig. 5 shows a schematic representation of a cross section of a second embodiment 21 of the hollow cylinder of a device in accordance with the present invention, Fig. 6 shows an enlarged representation of a side view of segment F in Fig. 5, Fig. 7 shows an enlarged representation of a small part of a cross section of the wall 26 in Fig. 5, Fig. 8 shows a cross section of a feed conduit 31 which is used in the hollow cylinder 21 in accordance with Fig. 5, Fig. 9 shows a cross section of the hollow cylinder 21 in accordance with Fig. 5 with a feed conduit 31 inserted in this hollow cylinder. Fig. 10 shows a schematic representation of an arrangement in which a device according to the present invention is used for the production of powders from solutions, dispersions, emulsions and melts, preferably from emulsions, Fig. 11 shows a diagram from which the narrow particle size distribution, presented as volume distribution, achieved with a device of the present invention is evident. BASIC STRUCTURE OF A DEVICE IN ACCORDANCE WITH THE INVENTION As shown in Fig. 1, the device in accordance with the present invention comprises the following components: - a rotatable hollow cylinder 11 or 21 for the reception of the liquid to be atomized, - a drive 12, preferably electromechanical, for the rotation of the hollow cylinder 11 or 21, and - means by which the liquid to be atomized is introduced into the hollow cylinder 11 or 21 under a certain pressure. This pressure is, e.g., between 0.3 and 5 bar. The last-mentioned means can comprise, e.g., a co-rotating hollow shaft 19 which is also rotatable from drive 12 and which, in turn, is connected, e.g., via a pump with a source of the liquid to be atomized and on the other hand with the hollow cylinder 11 or 21. The hollow cylinder 11 or 21 can be manufactured from all materials which can be mechanically processed for the purpose described here, e.g., from a metal, such as steel or steel alloy, or a plastic, such as polyvinyl chloride or polyethylene. The drive 12 allows the hollow cylinder 11 to be rotated at a speed of rotation being in a range of from 2000 to 20000 revolutions per minute, preferably from 3000 to 10000 revolutions per minute. Two different embodiments of a device according to the present invention are described hereinafter. FIRST EXAMPLE OF A DEVICE IN ACCORDANCE WITH THE INVENTION A first embodiment of a device in accordance with the present invention has the basic structure in accordance with Fig. 1 described above and contains a hollow cylinder 11 in accordance with Figures 2-4. As will be evident from Fig. 2, the hollow cylinder 11 is closed at its bottom end with a floor 13 and has an opening 15 at its upper end. As shown in detail in Figures 3 and 4, the cylindrical casing 16 of the hollow cylinder 11 has a plurality of circular hole-type nozzles 18 for the introduction of the liquid to be atomized. The hollow cylinder 11 is removably attached at its upper end to a co-rotating hollow shaft 19 through which liquid can be introduced into the hollow cylinder 11 through the opening 15. Preferably, the hollow cylinder 11 can be screwed on to the co-rotating hollow shaft 19. This has the advantage that the hollow cylinder 11 can be mounted and dismounted without special tools. The hollow cylinder 11 has a diameter within a range of from 10 to 25 millimeter. The surface of the cylinder casing 16 carrying the circular hole-type nozzles 18, extends in the axial direction over a length between 20 and 120 millimeter. Each of the circular hole-type nozzles 18 in the casing 16 of the hollow cylinder 11 has a hole diameter being in the range of from 0.05 tol millimeter, preferably in the range of from 0.1 to 0.4 millimeter. Each of the circular hole-type nozzles 18 in the casing 16 of the hollow cylinder 11 has a length/hole diameter ratio which is in a range of from 1 to 50, preferably from 2 to 10. With the above-described construction of the hollow cylinder 11a laminar thread-like disintegration and therewith a narrow droplet size distribution upon droplet dispersion can be achieved by suitable choice of the viscosity of the liquid to be atomized, the throughput of the liquid to be atomized, and the rotation and the diameter of the hollow cylinder 11. The average droplet size during the spraying will be in the range of from 50 to 500 micrometer, preferably from 100 to 350 micrometer. SECOND EXAMPLE OF A DEVICE IN ACCORDANCE WITH THE INVENTION An embodiment of the device according to the present invention has the basic structure in accordance with Fig. 1 described above, but contains in place of the hollow cylinder 11 in accordance with Figures 1-3 an arrangement in accordance with Figures 5-9, which arrangement contains a rotatable hollow cylinder 21 for the reception of the liquid to be atomized and an feed conduit 31 which is rotatable with the hollow cylinder 21 and through which the liquid to be atomized can be introduced into the hollow cylinder 21. As will be evident from Fig. 5, the hollow cylinder 21 is closed at its bottom end with a floor 23 and has an opening 25 at its upper end. As shown in detail in Figures 6 and 7, the casing 26 of the hollow cylinder 11 has a plurality of circular hole-type nozzles 28 for the introduction of the liquid to be atomized. The hollow cylinder 21 is removably attached at its upper end to a co-rotating hollow shaft 19 through which liquid is introduced into the hollow cylinder 21 through the opening 25. Preferably, the hollow cylinder 11 can be screw-mounted on the co-rotating hollow shaft 19. This has the advantage that the hollow cylinder 11 can be mounted and dismounted without special tools. The hollow cylinder 21 has a diameter being in the range of from 10 to 60 millimeter, preferably from 20 to 40 millimeter. The surface of the cylinder casing 26, which carries the circular hole-type nozzles 28, extends in the axial direction over a length being in the range of from 120 to 400 millimeter, preferably from 120 to 250 millimeter. Each of the circular hole-type nozzles 28 in the casing 26 of the hollow cylinder 21 has a hole diameter which is in the range of from 0.05 to 1 millimeter, preferably from 0.1 to 0.4 millimeter. Each of the circular hole-type nozzles 28 in the casing 26 of the hollow cylinder 21 has a length/hole diameter ratio in the range of from 1 to 50, preferably from 2 to 10. The feed conduit 31 is arranged in the cylinder 21 such that the longitudinal axis 34 of the feed conduit 31 coincides with the axis of rotation 27 of the hollow cylinder 21. The inlet 32 of the feed conduit 31 is attached to the opening 25 of the hollow cylinder 21 and thereby to the source of the liquid to be atomized. The outlet 33 of the feed conduit 31 is arranged inside the hollow cylinder 21 and at its end region where the floor of the hollow cylinder is located. The outlet 33 of the feed conduit 31 is directed towards the inner side of the cylinder casing 26, with the distance between this outlet 33 and the inner side of the cylinder floor 23 being much smaller than the distance between this outlet 33 and the opening 25 of the hollow cylinder 21. The distance between the outlet 33 of the feed conduit 31 and the inner side of the cylinder floor 23 is preferably in a range of from 1 to 20 millimeter. In a preferred embodiment the cylindrical side wall 35 of the feed conduit 31 has, in addition to the aforementioned outlet 33, several openings, with all of these openings being arranged in the axial direction between its inlet 32 and its outlet 33. EXAMPLES OF METHODS WHICH CAN BE CARRIED OUT WITH A DEVICE IN ACCORDANCE WITH THE INVENTION The following methods 1) to 5), inter alia, can be carried out, for example, with a device according to the present invention, with all circular hole-type nozzles in the casing of the hollow cylinder 11 or 21 being filled completely with the liquid and with the liquid throughput through the hollow cylinder being adjusted such that the liquid flows through the circular hole-type nozzles with a flow rate in the range of from 0.1 to 2.0 m/s, preferably from 0.3 tol.O m/s. 1) A method for atomizing a liquid in which the liquid is atomized by means of one of the devices as described above. 2) A method for spray cooling of a liquid in which the liquid is atomized by means of one of the devices as described above, with the hollow cylinder 11 or 21 being arranged in a gas stream, e.g., in a stream of air with an air temperature being in the range of from 5° to 50°C. Other gases, e.g., nitrogen, can be used instead of air. 3) A method for spray cooling of a liquid in which the liquid is atomized by means of one of the devices as described above, with the spraying being carried out in an indirectly tempered room in which the room temperature is in the range of from 5° to 50°C. 4) A method for spray drying of a liquid in which the liquid is atomized by means of one of the devices as described above, with the hollow cylinder 11 or 21 being arranged in a gas stream with a gas temperature being in a range of from HO' to 300°C. 5) A method for spray drying of a liquid in which the liquid is atomized by means of one of the devices as described above, with the spraying being carried out in an indirectly tempered room in which the room temperature is in the range of from 140° to 300°C. The narrow particle size distribution which can be achieved with the devices in accordance with the present invention which are described above is presented as a volume distribution in the diagram in accordance with Fig. 11. Procedural Examples The atomization procedure which can be carried out with the devices in accordance with the present invention described above can be used on a large scale for the production of powders from solutions, dispersions, preferably emulsions, as well as from melts. An example for the construction of the device required for this is presented schematically in Fig. 10. This construction comprises a stock container 41, a feed pump 42, a filter 43, a temperature-conditioned feed conduit 44, a spray container 45, a spray arrangement 46, a product discharge conduit 47 and optionally a supply conduit 48 for additives required, such as, e.g., silicic acid, starch, cold/warm air or other additives The mesh size of the filter 43 is selected as a function of the diameter of the hole of the circular hole-type nozzles 18 or 28. A filter 43 with a mesh size in a range of from 50 to 1000 micrometer is, e.g., selected for hole diameters in a range of from 0.05 to 1 millimeter. A filter 43 with a mesh size in a range of from 100 to 400 micrometer is selected for hole diameters in a range of from 0.1 to 0.4 millimeter. Procedural Example: Production of an active substance powder in a gelatin matrix An aqueous active substance (e.g., vitamin E) emulsion is stored in the stock container 41 at 60oC. The emulsion with a dry substance content of about 45-50% is conveyed via the feed pump 42 through the filter 43 with a typical mesh size of 100 to 300 micrometer to the spray arrangement 46. The emulsion in the spray container 45 is atomized via the described spray arrangement 46. The environmental temperature in the spray container 45 is 20°C. The required additives 8 are simultaneously dosed into the spray container 45. The spraying is carried out with the spray arrangement 46, which has the following features: Circular hole diameter DB = 0.3 millimeter, Number of circular hole-type nozzles = 1000 Cylinder wall thickness s = 1 millimeter Diameter of the hollow cylinder DC = 25 millimeter Nozzle rotation n = 7000 revolutions/minute Emulsion throughput: 150 kg/hour. A powder with an average particle size of 200 to 250 micrometer is obtained at the outlet 47 of the spray container 45. Although preferred procedural examples of the invention with specific details are described in the previous description, it should be clear that such a description serves only for illustration and that alterations and modifications of such procedural examples are realizable without deviating from the essential teaching of the invention, which is defined by the claims hereinafter. Reference list 11 Hollow cylinder 12 Rotation drive 13 Floor 15 Opening 16 Casing 17 Axis of rotation 18 Circular hole-type nozzle 19 Hollow shaft 21 Hollow cylinder 23 Floor 25 Opening 26 Casing 27 Axis of rotation 28 Circular hole-type nozzle 31 Feed conduit 32 Inlet 33 Outlet 34 Longitudinal axis 35 Wall 36 Floor 41 Stock container 42 Feed pump 43 Filter 44 Feed conduit 45 Spray container 46 Spray arrangement 47 Product discharge conduit 48 Supply conduit for additives WE CLAIM: 1. A device for atomizing liquids, which device comprises: - a rotatable hollow cylinder (11) for the reception of liquids to be atomized, and - a drive (12) for the rotation of the hollow cylinder (11), with the hollow cylinder being closed at its lower end with a floor (13) and having an opening (15) at its upper end, and its casing (16) having a plurality of circular hole-type nozzles (18) for the introduction of liquids to be atomized, wherein (a) the hollow cylinder (11) has a diameter which is in the range of from 10 to 25 millimeter, and (b) the surface of the cylinder casing (16), which has the circular hole-type nozzles (18), extends in the axial direction over a length in the range of from 20 to 120 millimeter. 2. The device as claimed in claim 1, wherein the hollow cylinder (11) is removably attached at its upper end to a co-rotating hollow shaft (19) through which liquids can be introduced into the hollow cylinder (11) 20 through the opening (15). 3. The device as claimed in claim 2, wherein the hollow cylinder (11) is screw-mounted on the co-rotating hollow shaft (19). 4. The device as claimed in claim 1, wherein each of the circular hole-type nozzles (18) in the casing (16) of the hollow cylinder (11) has a hole diameter in the range of from 0.05 to 1 millimeter. 5. The device as claimed in claim 4, wherein the liquid to be atomized is introduced into the hollow cylinder (11) through a filter (43) which allows the passage of particles having a size below a determined value which is in the range of from 50 to 1000 micrometer. 6. The device as claimed in claim 1, wherein each of the circular hole-type nozzles (18) in the casing (16) of the hollow cylinder (11) has a hole diameter which is in the range of form 0.1 to 0.4 millimeter. 7. The device as claimed in claim 6, wherein the liquid to be atomized is introduced into the hollow cylinder (11) through a filter (43) which allows the passage of particles having a size below a determined value being in the range of from 100 to 400 micrometer, 8. The device as claimed in claim 1, wherein each of the circular hole-type nozzles (18) in the casing (16) of the hollow cylinder (11) has a length/hole diameter ratio in the range of from 1 to 50. 9. The device as claimed in claim 1, wherein each of the circular hole-type nozzles (18) in the casing (16) of the hollow cylinder (11) has a length/hole diameter ratio in the range of from 2 to 10. 10. The device as claimed in claim 1, wherein the drive (12) for the rotation of the hollow cylinder (11) allows a speed of rotation which is in the range of from 2000 to 20000 revolutions per minute. 11. The device as claimed in claim 1, wherein the drive (12) for the rotation of the hollow cylinder (11) allows a speed of rotation which is in the range of from 3000 to 10000 revolutions per minute. 12. A device for the atomizing liquids, which device comprises: - a rotatable hollow cylinder (21) for the reception of liquids to be atomized, and - a drive (12) for the rotation of the hollow cylinder (21), with the hollow cylinder (21) being closed at its lower end with a floor (23) and having an opening (25) at its upper end, and its casing (26) having a plurality of circular hole-type nozzles (28) for the introduction of liquids to be atomized, and which device also contains a feed conduit (31) which is rotatable with the hollow cylinder (21) and through which liquids to be atomized can be introduced into the hollow cylinder (21), with the inlet (32) of the feed conduit (31) being attached to the opening (25) of the hollow cylinder (21) and thereby to the source of the liquid to be atomized, with the outlet (33) of the feed conduit (31) being arranged inside the hollow cylinder (21) and at its end region in which the floor of the hollow cylinder lies, and with the feed conduit (31) being arranged in the hollow cylinder (21) such that the longitudinal axis (34) of the feed conduit (31) coincides with the axis of rotation (27) of the hollow cylinder (21), the feed conduit (31) extends along the axis of rotation (27) of the hollow cylinder (21) and its outlet (33) is directed towards the inner side of the cylinder wall 26, with the distance between this outlet and the inner side of the cylinder floor (23) being much smaller than the distance between this outlet (33) and the opening (25) of the hollow cylinder (21). 13. The device as claimed in claim 12, wherein the distance between the outlet (33) of the feed conduit (31) and the inner side of the cylinder floor (23) is in the range of from 1 to 20 millimeter. 14. The device as claimed in claim 12, wherein the wall (35) of the feed conduit (31) has several openings in addition to the outlet (33) mentioned above, with all of these openings being arranged in the axial direction between its inlet (32) and its outlet (33). 15. The device as claimed in claim 12, wherein : (a) the hollow cylinder (21) has a diameter in the range of from 10 to 60 millimeter, and (b) the area of the cylinder casing (26), which has the circular hole-type nozzles (28), extends in the axial direction over a length in the range of from 120 to 400 millimeter. 16. The device as claimed in claim 12, wherein: (a) the hollow cylinder (21) has a diameter in the range of from 20 to 40 millimeter, and (b) the area of the cylinder casing (26), which has the circular hole type nozzles (28), extends in the axial direction over a length in the range of from 120 to 250 millimeter. 17. The device as claimed in claim 12, wherein the hollow cylinder (21) is removably attached at its upper end to a co-rotating hollow shaft (19) through which liquid can be introduced into the hollow cylinder (21) through the opening (25). 18. The device as claimed in claim 13, wherein the hollow cylinder (21) is screw-mounted on the co-rotating hollow shaft (19). 19. The device as claimed in claim 12, wherein each of the circular hole-type nozzles (28) in the cylinder casing (26) of the hollow cylinder (21) has a hole diameter being in the range of from 0.05 to 1 millimeter. 20. The device as claimed in claim 19, wherein the liquid to be atomized is introduced into the hollow cylinder (21) through a filter (43) which allows the passage of particles having a size below a determined value in the range of from 50 to 1000 micrometer. 21. The device as claimed in claim 12, wherein each of the circular hole-type nozzles (28) in the cylinder casing (26) of the hollow cylinder (21) has a hole diameter in the range of from 0.1 to 0.4 millimeter. 22. The device as claimed in claim 21, wherein the liquid to be atomized is introduced into the hollow cylinder (21) through a filter (43) which allows the passage of particles having a size below a determined value in the range of from 100 to 400 micrometer. 23. The device as claimed in claim 12, wherein each of the circular hole-type nozzles (28) in the cylinder casing (26) of the hollow cylinder (21) has a length/hole diameter ratio which is in the range of from 1 to 50. 24. The device as claimed in claim 12, wherein each of the circular hole-type nozzles (28) in the cylinder casing (26) of the hollow cylinder (21) has a length/hole diameter ratio which is in the range of from 2 to 10. 25. The device as claimed in claim 12, wherein the drive (12) for the rotation of the hollow cylinder (21) allows a speed of rotation in the range of from 2000 to 20000 revolutions per minute. 26. The device as claimed in claim 12, wherein the drive (12) for the rotation of the hollow cylinder (21) allows a speed of rotation in the range of from 3000 to 10000 revolutions per minute. 27. The device as claimed in any one of claims 1 to 26, wherein by suitable choice of the viscosity of the liquid to be atomized, speed of rotation and diameter of the hollow cylinder (11, 21) a narrow droplet size distribution can be achieved by the generation of a laminar thread-like disintegration by droplet dispersion, with the average droplet size during the spraying being in the range of from 100 to 350 micrometer. 28. The method for spray drying of a liquid, wherein the liquid is atomized by means of a device as claimed in any one of claims 1 to 11 or any one of claims 12 to 27 and wherein the hollow cylinder (11, 21) is arranged in a gas stream with a gas temperature in the range of from 140 to 300°C. 29. The method for spray drying of a liquid, wherein the liquid is atomized by means of a device as claimed in any one of claims 1 to 11 or any one of claims 12 to 27 and wherein the spraying is carried out in an indirectly tempered room in which the room temperature is in the range of from 140° to 300°C. 30. The method as claimed in any one of claims 28, 29, wherein the liquid is introduced under a pressure which is in the range of from 0.3 to 5 bar. 31. The method as claimed in any one of claims 28 to 30, wherein by suitable choice of the viscosity of the liquid to be atomized, the throughput of the liquid to be atomized, the speed of rotation of the hollow cylinder (11, 21), the diameter of the hollow cylinder (11, 21) and the circular hole diameter (18, 28) a narrow droplet size distribution can be achieved by the generation of a laminar thread-like disintegration by droplet dispersion, with the average droplet size during the spraying being in the range of from 50 to 500 micrometer. 32. The method as claimed in any one of claims 28 to 31, wherein by suitable choice of the viscosity of the liquid to be atomized, the throughput of the liquid to be atomized, the speed of rotation of the hollow cylinder (11, 21), the diameter of the hollow cylinder (11, 21) and the circular hole diameter (18, 28) a narrow droplet size distribution can be achieved by the generation of a laminar thread-like disintegration by droplet dispersion, with the average droplet size during the spraying being in the range of from 100 to 350 micrometer. 33. The method as claimed in any one of claims 28 to 32, wherein the throughput of liquids through the hollow cylinder (11, 21) is adjusted such that the liquid flows through the circular hole-type nozzles (18, 28) with a flow rate being in the range of from 0.1 to 2.0 m/s, preferably from 0.3 to 1.0 m/s. DATED THIS 3 DAY OF SEPTEMBER 2001

Documents:

0719-mas-2001 abstract duplicate.pdf

0719-mas-2001 claims duplicate.pdf

0719-mas-2001 description (complete) duplicate.pdf

0719-mas-2001 drawings duplicate.pdf

0719-mas-2001 petition.pdf

719-mas-2001-abstract.pdf

719-mas-2001-assignement.pdf

719-mas-2001-claims.pdf

719-mas-2001-correspondnece-others.pdf

719-mas-2001-correspondnece-po.pdf

719-mas-2001-description(complete).pdf

719-mas-2001-drawings.pdf

719-mas-2001-form 1.pdf

719-mas-2001-form 18.pdf

719-mas-2001-form 26.pdf

719-mas-2001-form 3.pdf

719-mas-2001-form 5.pdf