Energy recovery in a freeze-drying system

• US 10,113,797 B2
• Filed: 09/09/2016
• Issued: 10/30/2018
• Est. Priority Date: 09/09/2016
• Status: Active Grant

• Current Assignee: SP Industries Incorporated (ATS Corp.)
• Original Assignee: SP Industries Incorporated (ATS Corp.)
• Inventors: Dern, Charles D.
• Primary Examiner(s): Gravini, Stephen M
• Application Number:
  US15/260,539
• Publication Number:
  US 20180073806A1
• Time in Patent Office: 781 Days
• Field of Search: 34284, 34 92
• CPC Class Codes: A23F 5/32 by lyophilisation
• CPC Class Codes: A23L 3/44 Freeze-drying
• CPC Class Codes: A61K 9/19 lyophilised , i.e. freeze-dried, solutions or dispersions lyophilised products with subsequent particle size reduction A61K9/14; granules or pellets made by lyphilisation A61K9/1682; solid oral dosage forms made by lyophilisation A61K9/2095; lyophilisation additives A61K47/00
• CPC Class Codes: F25B 13/00 Compression machines, plants or systems, with reversible cycle defrosting cycles F25B47/02
• CPC Class Codes: F26B 23/001 using waste heat
• CPC Class Codes: F26B 5/06 the process involving freezing
• CPC Class Codes: F26B 9/066 the products to be dried being disposed on one or more containers, which may have at least partly gas-previous walls, e.g. trays or shelves in a stack F26B9/003 takes precedence; in combination with duct systems F26B21/00
• CPC Class Codes: Y02P 60/85 Food storage or conservation, e.g. cooling or drying
• CPC Class Codes: Y02P 70/10 Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

Abstract

Disclosed herein are embodiments of an energy recovery system for a freeze-drying system. In some embodiments, the freeze-drying system includes a freeze dryer chamber having one or more shelves disposed therein; a refrigeration system comprising a refrigerant condenser; a heat exchanger; a first fluid line to thermally couple the refrigerant condenser to the heat exchanger; and a second fluid line to thermally couple the one or more shelves to the heat exchanger.

Claims

1. A freeze-drying system comprising:

a freeze dryer chamber having one or more shelves disposed therein;

a refrigeration system comprising a refrigerant condenser;

a heat exchanger;

a first fluid line that passes through the refrigerant condenser and the heat exchanger defining a first fluid flow path therebetween, wherein the first fluid line is arranged to thermally couple the refrigerant condenser to the heat exchanger; and

a second fluid line, separate from the first fluid line, that passes through the one or more shelves and the heat exchanger and is adapted to alternate between a second fluid flow path and a third fluid flow path, wherein the second fluid flow path is defined through the one or more shelves and the heat exchanger, wherein the third fluid flow path is defined through the one or more shelves, and wherein the second fluid line is arranged to thermally couple the one or more shelves to the heat exchanger to facilitate transfer of refrigerant condenser-produced heat to the one or more shelves when the second fluid line defines the second fluid flow path.

2. The freeze-drying system of claim 1, wherein the second fluid line comprises a first valve and a second valve.

3. The freeze-drying system of claim 2, wherein the second fluid line defines the second fluid flow path from the one or more shelves to the heat exchanger when the first valve is open and when the second valve is closed.

4. The freeze-drying system of claim 3, wherein the first fluid line and the second fluid line facilitate the heat transfer between a heat exchanger of the refrigerant condenser and the one or more shelves when a first fluid flows through the first fluid flow path and a second fluid flows through second fluid flow path.

5. The freeze-drying system of claim 3, wherein the first fluid line defines the third fluid flow path that bypasses the heat exchanger when the first valve is closed and when the second valve is open.

6. The freeze-drying system of claim 3, further comprising:

a flow controller, wherein the flow controller is to regulate fluid flow through the first fluid line and the second fluid line.

7. The freeze-drying system of claim 6, further comprising:

a plurality of temperature sensing elements distributed throughout the first fluid line and the second fluid line.

8. The freeze-drying system of claim 6, wherein the flow controller is operatively coupled to the plurality of temperature sensors, and wherein the flow controller is to control the first valve and the second valve based on temperature measurements received from the plurality of temperature sensors.

9. The freeze-drying system of claim 7, wherein flow controller is to modulate the first valve to open and the second valve to close, or to modulate the first valve to close and the second valve to open, in response to determining that a temperature measurement satisfies a temperature threshold condition.

10. A method for energy recovery in a freeze-drying system, the method comprising:

causing, by a processing device of the freeze-drying system, a first fluid to flow through a first fluid flow path of a first fluid line that passes through a refrigerant condenser and a heat exchanger of the freeze-drying system, wherein the first fluid line is thermally coupled to the refrigerant condenser and the heat exchanger;

causing, by the processing device, a second fluid to flow through a second fluid flow path of a second fluid line that passes through the heat exchanger and one or more shelves disposed within a chamber of the freeze-drying system, wherein the second fluid flow path passes through the one or more shelves and bypasses the heat exchanger, and wherein the second fluid line is thermally coupled to the one or more shelves;

in response to a determination by the processing device that a freeze-drying process condition is satisfied, causing, by the processing device, the second fluid to flow through a third fluid flow path of the second fluid line, wherein the third fluid flow path passes through the one or more shelves and the heat exchanger, wherein flowing the second fluid through the third fluid flow path thermally couples the one or more shelves to the heat exchanger to facilitate transfer of refrigerant condenser-produced heat to the one or more shelves, wherein the determination that the freeze-drying process condition has been satisfied comprises a determination that;

a temperature of the first fluid or the second fluid has reached a target temperature,

the one or more shelves have reached a target temperature,

a particular step in a process recipe has occurred, or

a user of the freeze-drying system has entered a command to override the process recipe.

11. The method of claim 10, further comprising:

in response to a determination by the processing device that the freeze-drying process condition is no longer satisfied, causing, by the processing device, the second fluid to flow through the second fluid flow path of the second fluid line so as to fluidly uncouple the one or more shelves from the heat exchanger.

12. The method of claim 10, further comprising:

in response to a determination by the processing device that the one or more shelves have reached a target temperature, causing, by the processing device, the second fluid to flow through the second fluid flow path of the second fluid line so as to fluidly uncouple the one or more shelves from the heat exchanger.

13. The method of claim 10, wherein when the one or more shelves are thermally coupled to the heat exchanger, heat from the refrigerant condenser is transferred to the one or more shelves.

14. The method of claim 10, further comprising:

measuring the temperature of the first fluid, wherein the freeze-drying process condition comprises determining, by the processing device, that the temperature of the first fluid has reached the target temperature.

15. The method of claim 14, wherein the target temperature corresponds to a temperature that is greater than that of the second fluid.

16. The method of claim 10, wherein causing the second fluid to flow through the third fluid flow path comprises opening a first valve and closing a second valve to divert the second fluid through the third fluid flow path.

17. A method for energy recovery in a freeze-drying system, the method comprising:

causing, by a processing device of the freeze-drying system, a first fluid to flow through a first fluid flow path of a first fluid line that passes through a heat exchanger and one or more shelves disposed within a chamber of a freeze-drying system, wherein the first fluid line is thermally coupled to the one or more shelves and the heat exchanger;

causing, by the processing device, a second fluid to flow through a second fluid flow path of a second fluid line that passes through the heat exchanger and a refrigerant condenser of the freeze-drying system, wherein the second fluid flow path passes through the refrigerant condenser and bypasses the heat exchanger, and wherein the second fluid line is thermally coupled to the refrigerant condenser;

in response to a determination by the processing device that a freeze-drying process condition is satisfied, causing, by the processing device, the second fluid to flow through a third fluid flow path of the second fluid line, wherein the third fluid flow path passes through the refrigerant condenser and the heat exchanger, wherein flowing the second fluid through the third fluid flow path thermally couples the refrigerant condenser to the heat exchanger to facilitate transfer of refrigerant condenser-produced heat to the one or more shelves, wherein the determination that the freeze-drying process condition has been satisfied comprises a determination that;

a temperature of the first fluid or the second fluid has reached a target temperature,

the one or more shelves have reached a target temperature,

a particular step in a process recipe has occurred, or

a user of the freeze-drying system has entered a command to override the process recipe.

18. The method of claim 17, further comprising:

in response to a determination by the processing device that the freeze-drying process condition is no longer satisfied, causing, by the processing device, the second fluid to flow through the second fluid flow path of the second fluid line so as to fluidly uncouple the refrigerant condenser from the heat exchanger.