Heat recovery system

Patent metadata

Field	Value
Publication number	US-9476643-B2
Application number	US-201213432051-A
Country	US
Kind code	B2
Filing date	Mar 28, 2012
Priority date	Mar 29, 2011
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

The heat recovery system includes an oven having a treatment air with a treatment air temperature and a treatment air dew point temperature to treat a product or product in process. A zone outlet exhaust waste treatment air following the treatment of the product. A preheating zone includes a preheating inlet for the introduction of preheating air having a preheating air temperature and a preheating air dew point temperature to preheat the product. A transfer duct extends between the zone outlet of the oven and the preheating zone to transfer a portion of waste treatment air from the oven to the preheating zone to create the preheating air to preheat additional product. The preheating air preheats the product in the preheating zone to a product temperature that is at least equal to the treatment air dew point temperature to eliminate surface condensation on the product during treatment in the oven.

First claim

What is claimed is:

1. A method of recycling waste treatment air used in a heat recovery system having a preheating zone and a downstream oven zone of an oven for creating a preheating air to preheat a product in process prior to entering the downstream oven zone, the downstream oven zone having a zone outlet and a zone inlet, the preheating zone having a preheating inlet and a preheating outlet, the method comprising the steps of:
exhausting a waste treatment air through an oven duct assembly secured to the zone outlet in the downstream oven zone following a treatment of a product in process;
transferring at least a portion of the waste treatment air from the zone outlet to the zone inlet;
transferring a portion of the waste treatment air through a transfer duct extending between the oven duct assembly and the preheating zone;
conditioning the waste treatment air to create a preheating air having a preheating air temperature and a preheating air dew point temperature;
introducing the preheating air into the preheating zone through the preheating inlet to preheat additional product in process;
exhausting a waste preheating air through the preheating outlet in the preheating zone following the preheating of the product in process; and
connecting the preheating outlet to the preheating inlet with a preheating duct assembly to transfer at least a portion of the waste preheating air from the preheating outlet to the preheating inlet, and conditioning the at least a portion of the waste preheating air for creating a new preheating air to preheat additional product in process.

2. The method of recycling waste treatment air as set forth in claim 1 further including the step of introducing a treatment air having a treatment air temperature and a treatment air dew point temperature into the oven zone through the zone inlet for treating the product in process.

3. The method of recycling waste treatment air as set forth in claim 2 further including the step of preheating the product in process to a product temperature being at least equal to the treatment air dew point temperature of the treatment air in the oven zone for eliminating surface condensation on the product in process during the introducing treatment air step.

4. The method of recycling waste treatment air as set forth in claim 2 further including the step of connecting the zone outlet to the zone inlet with the oven duct assembly.

5. The method of recycling waste treatment air as set forth in claim 1 further including the step of conditioning the waste treatment air in the oven duct assembly.

6. The method of recycling waste treatment air as set forth in claim 5 wherein the step of conditioning the waste treatment air is further defined by heating the waste treatment air with an oven heat source.

7. The method of recycling waste treatment air as set forth in claim 5 wherein the step of conditioning the waste treatment air is further defined by introducing ambient air to the waste treatment air.

8. The method of recycling waste treatment air as set forth in claim 7 wherein the step of introducing ambient air is further defined by controlling the flows of the treatment air, the waste treatment air and the ambient air, through, into and out the treatment duct assembly with a treatment duct regulator.

9. The method of recycling waste treatment air as set forth in claim 7 further including the step of treating the product in process in the downstream oven zone with the treatment air.

10. The method of recycling waste treatment air as set forth in claim 9 wherein the treating the product in process step is further defined as heating the product in process to dry, bake, rehydrate, ferment or toast the product in process.

11. The method of recycling waste treatment air as set forth in claim 1 wherein the transferring step is further defined as transferring a portion of waste treatment air through a transfer duct extending between the oven duct assembly.

12. The method of recycling waste treatment air as set forth in claim 1 wherein the step of conditioning the waste preheating air is further defined by introducing ambient air to the waste preheating air to condition the waste preheating air.

13. The method of recycling waste treatment air as set forth in claim 12 further including the step of controlling the flows of the preheating air, the waste preheating air, the waste treatment air and the ambient air, through, into and out the preheating duct assembly with a preheating duct regulator.

14. The method of recycling waste treatment air as set forth in claim 1 further including the step of preheating the product in process in the preheating zone with the preheating air for eliminating surface condensation on the product in process during treatment in the downstream oven zone.

15. The method of recycling waste treatment air as set forth in claim 3 wherein the preheating the product in process step is further defined as heating the product in process in the preheating zone with the preheating air to a product temperature being greater than the treatment air dew point temperature.

16. The method of recycling waste treatment air as set forth in claim 1 further including the step of moving the product in process in the downstream direction along a transfer device through the preheating zone and the downstream oven zone.

17. The method of recycling waste treatment air as set forth in claim 1 further including the step of transferring at least a portion of the waste preheating air from the preheating outlet to the preheating inlet.

18. The method of recycling waste treatment air as set forth in claim 1 wherein transferring a portion of the waste treatment air through a transfer duct extending between the oven duct assembly and a preheating zone includes:
transferring waste treatment air from the zone inlet to the transfer duct; and
transferring waste treatment air from the transfer duct to the preheating inlet.

19. The method of recycling waste treatment air as set forth in claim 18 further including the step of transferring waste treatment air from the transfer duct to a first exhaust flue.

20. The method of recycling waste treatment air as set forth in claim 19 further including the step of transferring waste preheating air from the preheating duct assembly to a second exhaust flue.

Assignees

• Hirzel Nicholson
• Breslin James
• Kellog Co

Inventors

• Hirzel Nicholson
• Breslin James

Classifications

• F26B23/002 Primary

  recovered from dryer exhaust gases (F26B23/022 takes precedence) · CPC title

• A21B1/26

  by hot air · CPC title

• F26B15/12

  the lines being all horizontal or slightly inclined · CPC title

• A21B1/48

  with surfaces in the form of an endless band · CPC title

• A23B9/08

  Drying; Subsequent reconstitution · CPC title