Pasteurization system and method

• US 9,930,898 B2
• Filed: 07/29/2009
• Issued: 04/03/2018
• Est. Priority Date: 07/29/2009
• Status: Active Grant

• Current Assignee: Tokitae LLC (Intellectual Ventures LLC)
• Original Assignee: Tokitae LLC (Intellectual Ventures LLC)
• Inventors: Deane, Geoffrey F., Gates, William, Hyde, Roderick A., Kare, Jordin T., Myhrvold, Nathan P., Tuckerman, David B., Wood, Jr., Lowell L., Yildirim, Ozgur
• Primary Examiner(s): STAPLETON, ERIC S
• Application Number:
  US12/462,206
• Publication Number:
  US 20110023728A1
• Time in Patent Office: 3,170 Days
• Field of Search: 99483
• CPC Class Codes: A23C 3/0332 in contact with multiple heating plates
• CPC Class Codes: A23C 3/0335 the milk being heated by electrical or mechanical means, e.g. by friction
• CPC Class Codes: A23L 3/003 Control or safety devices for sterilisation or pasteurisation systems
• CPC Class Codes: A23L 3/22 with transport through tubes
• CPC Class Codes: C12H 1/18 by heating

Abstract

A pasteurization system includes a liquid inlet configured to receive a liquid to be pasteurized. The system also includes a pump coupled to the liquid inlet for pressurizing the liquid. Further, the system includes a counter flow heat exchanger coupled to the liquid inlet and the pump, the counterflow heat exchanger configured to heat the liquid to a predetermined temperature for at least a predetermined time and configured to exchange heat between a flow of liquid in a first direction in a first channel with the flow of liquid in a second direction opposite the first direction in a second channel. A heating section that heats the liquid flow is integrated into the heat exchanger and heats at least a portion of the first channel or the second channel.

Claims

1. A pasteurization system, comprising:

a liquid inlet configured to receive a liquid to be pasteurized;

a pump coupled to the liquid inlet for pressurizing the liquid; and

a counter flow heat exchanger coupled to the liquid inlet and the pump, the counter flow heat exchanger including at least a first channel and a second channel fluidly coupled in hydraulic communication with the first channel within the counter flow heat exchanger, wherein the first channel and the second channel are microchannels, the second channel being hydraulically coupled to receive the same liquid from the first channel such that the first channel and the second channel are hydraulically coupled to direct flow of the same liquid, the counter flow heat exchanger configured to heat the liquid to a predetermined temperature for at least a predetermined time and configured to exchange heat between a flow of the liquid in a first direction in the first channel with the flow of the liquid in the second direction opposite the first direction in a second channel, where the liquid is flowable from the first channel into the second channel, the counter flow heat exchanger including a heating section including an electric heater that provides a heat input and heats the liquid flow, the electric heater being disposed in thermal communication with at least a portion of the first channel or the second channel to heat at least the portion of the first channel or the second channel with the heat input from the electric heater, wherein an insulative layer at least partially insulates the first channel and the second channel; and

a heat exchanger outlet that feeds into a pressure relief valve.

2. The pasteurization system of claim 1, wherein the first channel and the second channel are separated by a thin wall.

3. The pasteurization system of claim 1, wherein the first channel and the second channel are separated by a thin wall and the thin wall has a thickness less than 0.01 centimeters.

4. The pasteurization system of claim 1, wherein the first channel and the second channel are separated by a thin wall and the thin wall has a thickness less than 0.002 centimeters.

5. The pasteurization system of claim 1, wherein the first channel and the second channel share a wall.

6. The pasteurization system of claim 1, wherein the first channel and the second channel share a wall and there exist multiple pairs of input channels and output channels in a row each pair sharing a wall with an adjacent pair.

7. The pasteurization system of claim 6, wherein the input and output channels are at least partially surrounded by an insulating layer.

8. The pasteurization system of claim 1, wherein the first and second channels each have a hydraulic diameter, each hydraulic diameter expressed as four times the cross sectional area of each of the first and second channels divided by the perimeter of the respective cross section, each hydraulic diameter being less than one millimeter.

9. The pasteurization system of claim 1, wherein the first channel and the second channel are at least partially formed of polyaryletheretherketone.

10. The pasteurization system of claim 1, wherein the heating section includes at least one of copper and aluminum plating between the heater and the channel.

11. The pasteurization system of claim 1, wherein the heating section includes at least one of copper and aluminum plating between the heater and at least the second channel.

12. The pasteurization system of claim 1, wherein the liquid to be pasteurized includes at least one of fruit juice, apple cider, honey, maple syrup, milk, soy sauce, sports drinks, vinegar, water, wine, beer, cream, and cheese.

13. The pasteurization system of claim 1, further comprising a filter configured to filter the liquid, the filter coupled to the inlet.

14. The pasteurization system of claim 1, wherein the first channel and the second channels are configured with aspect ratios which produce substantially laminar flow.

15. The pasteurization system of claim 1, wherein the first channel and the second channels are configured to induce liquid flow in the channel with a boundary layer thickness that is greater than one-half the thickness of the channel.

16. The pasteurization system of claim 1, wherein the insulative layer at least partially insulates the heating section.

17. The pasteurization system of claim 1, wherein the heat exchanger includes multiple pairs of first channels and second channels.

18. The pasteurization system of claim 1, wherein a first channel is adjacent to and receives heat from multiple second channels.

19. The pasteurization system of claim 1, wherein a second channel is adjacent to and transfers heat to multiple first channels.

20. The pasteurization system of claim 1, wherein there are multiple first channels and second channels and the first channels alternate with the second channels in a side-to-side relationship.

21. The pasteurization system of claim 1, further comprising support elements within at least one of the first channels and the second channels.

22. A pasteurization system, comprising:

a liquid inlet configured to receive a liquid to be pasteurized;

a pump coupled to the liquid inlet for pressurizing the liquid;

a microchannel heat exchanger coupled to the liquid inlet and the pump, the microchannel heat exchanger having microchannels and configured to heat the liquid to a predetermined temperature for at least a predetermined time and configured to exchange heat between flows of the same liquid where the microchannels are fluidly coupled in pairs in hydraulic communication with each other within the microchannel heat exchanger so that the same liquid is flowable from one of the microchannels into another of the microchannels fluidly coupled therewith within the microchannel heat exchanger and so that heat in one portion of the flow is transferred to another part of the flow of the same liquid, the microchannels of the microchannel heat exchanger each having a hydraulic diameter, the hydraulic diameter expressed as four times the cross sectional area of the respective microchannel divided by the perimeter of the cross section of the respective microchannel, the hydraulic diameter being less than one millimeter, the microchannel heat exchanger having a heating section including an electric heater that provides a heat input and heats the liquid flow, the electric heater being disposed in thermal communication with a portion of the pairs of microchannels and heating at least a portion of the pairs of microchannels with the heat input from the electric heater, wherein an insulative layer at least partially insulates the pairs of microchannels; and

a heat exchanger outlet that feeds into a pressure relief valve.

23. The pasteurization system of claim 22, wherein the heat exchanger is regenerative.

24. The pasteurization system of claim 22, wherein the liquid flows are counter flowing.

25. The pasteurization system of claim 22, wherein the heat exchanged is between different portions of the same liquid flow.

26. An ultra-high temperature milk pasteurization system, comprising:

a liquid inlet configured to receive milk to be pasteurized;

a pump coupled to the liquid inlet for pressurizing the milk;

a counter flow heat exchanger having adjacent microchannels fluidly coupled in hydraulic communication with each other within the counter flow heat exchanger, the counter flow heat exchanger coupled to the liquid inlet and configured to flow the same milk through one of the adjacent microchannels into the other of the adjacent microchannels fluidly coupled therewith within the counter flow heat exchanger and the counter flow heat exchanger configured to heat the milk to a temperature of at least 135 degrees Celcius for at least a period of one tenth of a second, the counter flow heat exchanger having a heating section including an electric heater that provides a heat input and heats the milk flow, the electric heater being disposed in thermal communication with a portion of one of the adjacent microchannels or the other of the adjacent microchannels and heating at least a portion of one of the adjacent microchannels or the other of the adjacent microchannels with heat input from the electric heater, wherein an insulative layer at least partially insulates the adjacent microchannels; and

a heat exchanger outlet that feeds into a pressure relief valve.

27. The ultra-high temperature milk pasteurization system of claim 26, wherein the heat exchanger is regenerative.

28. The ultra-high temperature milk pasteurization system of claim 26, wherein the heat exchanged is between different portions of the same milk flow.

29. A pasteurization system, comprising:

a liquid inlet configured to receive a liquid to be pasteurized;

a pump coupled to the liquid inlet for pressurizing the liquid; and

a counter flow heat exchanger having a first microchannel and a second microchannel coupled to the liquid inlet and the pump, the first microchannel and the second microchannel being fluidly coupled in hydraulic communication with each other within the counter flow heat exchanger, the counter flow heat exchanger configured to heat the liquid to a predetermined temperature for at least a predetermined time and configured to exchange heat between a flow of liquid in the first direction in the first microchannel with the flow of the same liquid in the second direction opposite the first direction in the second microchannel, where the same liquid is flowable from the first microchannel into the second microchannel within the counter flow heat exchanger, the counter flow heat exchanger having a heating section including an electric heater that provides a heat input and heats the liquid flow in at least one of the first microchannel and the second microchannel, the electric heater being disposed in thermal communication with at least a portion of at least one of the first microchannel and the second microchannel and heating at least a portion of at least one of the first microchannel and the second microchannel with the heat input from the electric heater, wherein an insulative layer at least partially insulates the first microchannel and the second microchannel; and

a heat exchanger outlet that feeds into a pressure relief valve.

30. A pasteurization system, comprising:

a liquid inlet configured to receive a liquid to be pasteurized;

a pump coupled to the liquid inlet for pressurizing the liquid;

a microchannel heat exchanger having multiple microchannels coupled to the liquid inlet and the pump, the microchannel heat exchanger configured to heat the liquid to a predetermined temperature for at least a predetermined time and configured to exchange heat between flows of the same liquid where the microchannels are fluidly coupled in pairs in hydraulic communication with each other within the microchannel heat exchanger so that the liquid is flowable from one of the microchannels into another of the microchannels fluidly coupled therewith within the microchannel heat exchanger and so that heat in one portion of the flow of the liquid is transferred to another part of the flow of the same liquid, the microchannels of the microchannel heat exchanger being configured to produce substantially laminar flow within the microchannels, the microchannel heat exchanger having a heating section including an electric heater that provides a heat input and heats the liquid flow, the electric heater being disposed in thermal communication with at least a portion of the pairs of microchannels and heating at least a portion of the pairs of microchannels with the heat input from the electric heater, wherein an insulative layer at least partially insulates the pairs of microchannels; and

a heat exchanger outlet that feeds into a pressure relief valve.

31. The pasteurization system of claim 30, wherein the heat exchanger is regenerative.

32. The pasteurization system of claim 30, wherein the liquid flows are counter flowing.

33. The pasteurization system of claim 30, wherein the heat exchanged is between different portions of the same liquid flow.