HEAT RECOVERY SYSTEM AND METHOD

• US 20120285167A1
• Filed: 07/24/2012
• Published: 11/15/2012
• Est. Priority Date: 11/15/2006
• Status: Active Grant

• Current Assignee: Modine Manufacturing Company
• Original Assignee: Modine Manufacturing Company
• Inventors: Horek, Jon, Wilson, Michael J., Voss, Mark
• Granted Patent: US 8,495,859 B2
• Time in Patent Office: Days
• US Class Current: 60/618
• CPC Class Codes: F28D 21/0003 the heat being recuperated from exhaust gases F28D21/0014 takes precedence
• CPC Class Codes: F28D 9/00 Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall F28F3/083, F28F3/086 take precedence

Abstract

The present invention provides an exhaust gas waste heat recovery heat exchanger including a housing having a working fluid inlet, a working fluid outlet, an exhaust inlet, and an exhaust outlet, an exhaust flow path extending through the housing between the exhaust inlet and the exhaust outlet, and a working fluid flow path extending through the housing between the working fluid inlet and the working fluid outlet and having a first portion and a second portion. A flow of working fluid along the first portion of the working fluid flow path can be substantially counter to a flow of exhaust along the exhaust flow path, and the flow of working fluid along the second portion of the working fluid flow path can be substantially parallel to the flow of exhaust along the exhaust flow path.

Claims

1. An exhaust gas waste heat recovery heat exchanger comprising:

a housing having a first working fluid inlet, a second working fluid inlet, a first working fluid outlet, a second working fluid outlet for dispensing a superheated vapor, an exhaust inlet, an exhaust outlet, a preheater, and a superheater;

an exhaust flow path extending between the exhaust inlet and the exhaust outlet through the preheater and the superheater;

a working fluid flow path extending through the housing between the first working fluid inlet and the second working fluid outlet, the working fluid flow path including,

a first portion that extends through the preheater from the first working fluid inlet to the first working fluid outlet, a flow of working fluid along the first portion of the working fluid flow path through the preheater receiving heat from the flow of exhaust traveling along the exhaust flow path, and

a second portion that extends through the superheater from the second working fluid inlet to the second working fluid outlet and spaced apart from the working fluid inlet, the flow of working fluid along the second portion of the working fluid flow path through the superheater receiving heat from the flow of exhaust traveling along the exhaust flow path.

2. The exhaust gas waste heat recovery heat exchanger of claim 1, wherein the preheater is adjacent the first working fluid inlet such that the working fluid flows through the first working fluid inlet and discharges into the preheater.

3. The exhaust gas waste heat recovery heat exchanger of claim 2, wherein the superheater is adjacent the second working fluid outlet such that the working fluid flows through the superheater and is discharged from the superheater through the second working fluid outlet.

4. The exhaust gas waste heat recovery heat exchanger of claim 1, wherein the preheater is adjacent the exhaust outlet.

5. The exhaust gas waste heat recovery heat exchanger of claim 4, wherein the superheater is adjacent the exhaust inlet.

6. The exhaust gas waste heat recovery heat exchanger of claim 1, wherein the housing including the preheater and the superheater is a single integral housing.

7. The exhaust gas waste heat recovery heat exchanger of claim 1, wherein the first portion of the working fluid flow path is adjacent the first working fluid inlet and the exhaust outlet and the second portion of the working fluid flow path is adjacent the second working fluid outlet and the exhaust inlet.

8. The exhaust gas waste heat recovery heat exchanger of claim 1, wherein heat transferred from the flow of exhaust traveling along the exhaust flow path to the working fluid traveling along the second portion of the working fluid flow path vaporizes and superheats the working fluid before the working fluid exits the housing through the second working fluid outlet.

9. The exhaust gas waste heat recovery heat exchanger of claim 1, wherein the housing substantially encloses the superheater operable to superheat the flow of working fluid traveling along the second portion of the working fluid flow path, and the preheater positioned along the first portion of the working fluid flow path and being operable to transfer heat from the flow of exhaust to the flow of working fluid traveling along the first portion of the working fluid flow path.

10. The exhaust gas waste heat recovery heat exchanger of claim 1, further comprising:

a vaporizer; and

a bypass extending outwardly from the housing between the first working fluid outlet and the inlet of the vaporizer, the working fluid flow path extending through the bypass.

11. The exhaust gas waste heat recovery heat exchanger of claim 1, wherein the exhaust inlet of the housing supplies exhaust to the superheater and the exhaust outlet of the housing vents the exhaust from the preheater.

12. A method of recovering waste heat from exhaust, the method comprising the acts of:

directing a flow of exhaust along an exhaust flow path through a housing of an exhaust gas waste heat recovery heat exchanger between an exhaust inlet defined in the housing and an exhaust outlet defined in the housing;

directing a flow of working fluid into a first working fluid inlet defined in the housing;

directing the flow of working fluid along a working fluid flow path through a preheater arranged within the housing;

transferring heat from the exhaust traveling along the exhaust flow path to the working fluid traveling through the preheater;

removing the flow of working fluid from the housing through a first working fluid outlet defined in the housing;

directing the flow of working fluid into a second working fluid inlet defined in the housing after having removed the flow of working fluid through the first working fluid outlet;

directing the flow of working fluid along a second portion of the working fluid flow path that extends through a superheater arranged within the housing;

transferring heat from the exhaust traveling along the exhaust flow path to the working fluid traveling through the superheater; and

removing the working fluid from the housing through the second working fluid outlet as a superheated vapor.

13. The method of claim 12, wherein transferring heat from the exhaust traveling along the exhaust flow path to the working fluid traveling along the second portion of the flow path includes vaporizing the working fluid adjacent an inlet to the second portion of the working fluid flow path.

14. The method of claim 12, wherein directing the flow of working fluid along the working fluid flow path includes directing the working fluid through the vaporizer to vaporize at least a portion of the flow of working fluid traveling along the working fluid flow path and the superheater to superheat at least a portion of the flow of working fluid traveling along the second portion of the working fluid flow path after directing the working fluid through the preheater.

15. The method of claim 12, wherein directing the flow of exhaust along the exhaust flow path through the housing includes transferring heat from the exhaust flow to the working fluid flow in the superheater before the exhaust flow enters the preheater.

16. The method of claim 12, wherein directing the flow of working fluid along the working fluid flow path includes directing the working fluid through the bypass extending outwardly from the housing and between the outlet of the preheater and the inlet of the vaporizer.

17. The method of claim 12, further comprising reducing a temperature difference between the exhaust flow and the working fluid flow in the preheater before directing the preheated working fluid from the first portion of the working fluid flow path to the second portion of the working fluid flow path.

18. The method of claim 12, wherein directing the flow of the working fluid along the working fluid flow path through the preheater and the superheater of the housing includes directing the flow of the working fluid through the housing including the preheater and the superheater as a single integral housing.