FREEZE DRYING PLANT AND METHOD

Abstract

A freeze drying plant for drying products containing liquid has a vacuum chamber configured to receive the products. A reception device has at least one reception plate onto which the products can be applied. A cooling system has a fluid circuit configured to cool and/or to heat the products by a cooling fluid conducted in the fluid circuit. The reception plate has at least one closed fluid space that is connected to the fluid circuit and that cooling fluid flows through. At least one sound generator introduces ultrasound into the products during a drying phase, with the sound generator disposed in the fluid space and being able to be flowed around by cooling fluid.

Claims

1. A freeze drying plant for drying products containing liquid, comprising: a vacuum chamber configured to receive the products containing liquid; a reception device having at least one reception plate onto which the products containing liquid can be placed; a cooling system having a fluid circuit is configured to cool and/or to heat the products by a cooling fluid conducted in the fluid circuit; wherein the reception plate has at least one closed fluid space that is connected to the fluid circuit and through which the cooling fluid flows; at least one sound generator configured to introduce ultrasound into the products during a drying phase, the sound generator being disposed in the fluid space so as to be flowed around by the cooling fluid.

2. The freeze drying plant in accordance with claim 1, wherein: the reception plate has a superficial extent and is configured as double-walled with an upper plate wall and a lower plate wall between which the fluid space is formed; at least one support surface for the support of the products is formed on the upper of the upper plate wall; and the at least one sound generator is arranged on a lower side of the upper plate wall.

3. The freeze drying plant in accordance with claim 1, further comprising a coolable condenser on which liquid removable from the products in a drying phase is precipitated from a vapor phase.

4. The freeze drying plant in accordance with claim 3, further comprising a condenser chamber, the coolable condenser being received in the condenser chamber, and the condenser chamber being connected to the vacuum chamber by an intermediate valve.

5. The freeze drying plant in accordance with claim 3, wherein the coolable condenser is configured together with the products that can be introduced in the vacuum chamber.

6. The freeze drying plant in accordance with claim 1, wherein the reception plate forms a base plate of the vacuum chamber that bounds the vacuum chamber at a lower side.

7. The freeze drying plant in accordance with claim 2, wherein the upper plate wall is formed as part of a housing body surrounding the vacuum chamber.

8. The freeze drying plant in accordance with claim 1, wherein the reception device has a plurality of reception plates arranged in levels above one another and having the fluid spaces formed thereby for receiving a plurality of the products.

9. The freeze drying plant in accordance with claim 3, wherein the coolable condenser is disposed in the vacuum chamber such that it surrounds the reception device having the products arrangeable therein.

10. The freeze drying plant in accordance with claim 1, wherein the at least one sound generator is configured to introduce ultrasound into the products at an ultrasonic frequency of 10 kHz to 100 kHz.

11. The freeze drying plant in accordance with claim 1, further comprising at least one sound device configured to introduce ultrasound into the products at an ultrasonic frequency of 10 kHz to 100 kHz in operative connection with the at least one sound generator.

12. The freeze drying plant in accordance with claim 11, wherein at least one the sound device is configured to introduce the ultrasound into the products in a pulsed manner in operative connection with the at least one sound generator.

13. The freeze drying plant in accordance with claim 12, wherein the at least one sound device is configured in operative connection with the sound generator to introduce ultrasound into the products by pulses in the range of infrasound of 0.1 Hz to 20 Hz.

14. The freeze drying plant in accordance with claim 2, wherein the at least one sound generator comprises a plurality of sound generators arranged next to one another at a lower side of the upper plate wall and within the fluid space, with the sound generators each having a dish shape with a sound surface by which the sound generators are arranged at the upper plate wall so that ultrasound can be superficially introduced into the upper plate wall.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Further measures improving the invention will be shown in more detail below together with the description of preferred embodiments of the invention with reference to the Figures. There are shown:

[0035] FIG. 1 is a schematic view of an embodiment of a freeze drying plant having a reception plate in accordance with the invention as a base plate of the vacuum chamber; and

[0036] FIG. 2 is a schematic view of an embodiment of a freeze drying plant having a plurality of reception plates in accordance with the invention that are arranged in levels above one another.

DETAILED DESCRIPTION OF THE INVENTION

[0037] FIG. 1 shows a freeze drying plant 1 that serves the drying of products 10 containing liquid, wherein the products 10 are represented as unit material and the products 10 containing liquid can also be bulk material.

[0038] The products 20 are received on a reception device 12 that comprises a single reception plate 13 by way of example. The reception plate 13 has a sandwich-like structure and has an upper plate wall 26 and a lower plate wall 27. A fluid space 17 that is filled with cooling fluid 16 is configured between the upper plate wall 26 and the lower plate wall 27.

[0039] The cooling fluid 16 is connected to a fluid circuit 15 that is either heated or cooled via a unit 25 depending on the phase of the cooling or heating of the products 10 in the freeze drying process of the freeze drying plant 1.

[0040] The upper plate wall 26 is designed in accordance with this embodiment as a base plate 23 of the housing body 29 of the vacuum chamber 11. To this extent, the base plate 23 and the upper plate wall 26 of the reception plate 13 form a unitary component, with a plurality of sound generators 18 being arranged on the lower side of the upper plate wall 26. The sound generators 18 are located at a respective position of the superficial reception plate 13 that coincides with the placement position of the products 10. If the sound generators 18 are operated, ultrasound can be introduced into the products 10 through the upper plate wall 26 or through the base plate 23. Furthermore, a facilitated heat transfer either into the product 10 if the cooling fluid 16 is heated or from the product 10 if the cooling fluid 16 is cooled by the wetting of the lower side of the upper plate wall 26 from the direction of the fluid space 17. The sound device 31 arranged outside the vacuum chamber 11 generates ultrasound by the sound generators 18, with the number of sound generators 18 shown being operated together by the one sound device 31.

[0041] FIG. 2 shows a further embodiment of a freeze drying plant 1 for drying products 10 containing liquid, wherein a reception device 12 having a plurality of reception plates 13 arranged above one another is introduced into the vacuum chamber 11. A condenser 22 is furthermore introduced within the vacuum chamber 11 and the condenser 22 is fluidically connected to a condenser unit 30 to cool the condenser 22.

[0042] The products 10 stand on the upper side of the respective reception plates 13 that are in turn set up in a sandwich-like manner by an upper plate wall 26 and a lower plate wall 27 and the fluid space 17 located therebetween. The sound generators 18 are arranged within the fluid space 17, with the fluid space 17 being filled with cooling fluid 16 that is fluidically connected to the unit 25 via the fluid circuit 15.

[0043] The embodiment shows that the reception plates 13 having the sandwich design also arranged in multiple form above one another can form the reception device 12 so that the reception plates 13 form the level bases in a certain manner that are each formed in a sandwich-like manner. The sound device shown in FIG. 1 in accordance with this embodiment can also control the sound generators 18 individually, group-wise or all together to introduce the ultrasound into the products 10 at frequencies of, for example, 10 kHz to 100 kHz, with the introduction, however, preferably—but not necessarily—taking place in pulsed form, for example with pulses from the infrasound range, in particular at pulse frequencies of 0.01 Hz to 20 Hz.

[0044] The invention is not restricted in its design to the preferred embodiment specified above. A number of variants is rather conceivable that also makes use of the solution shown with a generally differently designed embodiment. All the features and/or advantages, including any construction details or spatial arrangements, originating from the claims, the description, or the drawings can be essential to the invention both per se and in the most varied combinations.

REFERENCE NUMERAL LIST

[0045] 1 freeze-drying plant

[0046] 10 product

[0047] 11 vacuum chamber

[0048] 12 reception device

[0049] 13 reception plate

[0050] 14 cooling system

[0051] 15 fluid circuit

[0052] 16 cooling fluid

[0053] 17 fluid space

[0054] 18 sound generator

[0055] 19 condenser

[0056] 20 condenser chamber

[0057] 21 intermediate valve

[0058] 22 condenser

[0059] 23 base plate

[0060] 24 sound surface

[0061] 25 unit

[0062] 26 upper plate wall

[0063] 27 lower plate wall

[0064] 28 support surface

[0065] 29 housing body

[0066] 30 condenser unit

[0067] 31 sound device