Heat exchangers with floating headers

Patent metadata

Field	Value
Publication number	US-10488122-B2
Application number	US-201615359072-A
Country	US
Kind code	B2
Filing date	Nov 22, 2016
Priority date	Jun 29, 2012
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

A heat exchanger is comprised of two heat exchanger sections, at least one of which is provided with a floating header to accommodate differential thermal expansion. The two heat exchanger sections are enclosed by an inner shell wall, and an external connecting passage is provided outside the inner shell wall, through which one of the fluids flows between the two heat exchanger sections. The external connecting passage is enclosed by an outer shell. The inner wall is provided with openings which communicate with the external connecting passage. The openings may be in the form of a substantially continuous gap or discrete openings. Specific examples of heat exchangers with this construction include a steam generator, a steam generator and combined catalytic converter, and a water gas shift reactor.

First claim

What is claimed is:

1. A heat exchange device comprising a first heat exchanger section and a second heat exchanger section arranged in series, wherein the heat exchange device comprises:
(a) an inner shell having a first end and a second end, and having an inner shell wall extending along an axis between the first and second ends, wherein the first heat exchanger section and the second heat exchanger section are enclosed within the inner shell wall;
(b) a first fluid inlet provided in the first heat exchanger section and a first fluid outlet provided in the second heat exchanger section;
(c) a second fluid inlet provided in the second heat exchanger section and a second fluid outlet provided in the first heat exchanger section;
(d) an axially-extending first fluid flow passage extending through both the first and second heat exchanger sections from the first fluid inlet to the first fluid outlet, wherein the first fluid flows between the first and second heat exchanger sections through an internal connecting passage located inside the inner shell;
(e) an axially-extending second fluid flow passage extending through both the first and second heat exchanger sections from the second fluid inlet to the second fluid outlet, wherein the first and second fluid flow passages are sealed from one another, and wherein the second fluid flows between the second and first heat exchanger sections through an external connecting passage located outside the inner shell;
(f) an outer shell enclosing the external connecting passage;
(g) at least one aperture through the inner shell in the second heat exchanger section through which the second fluid flows from the second heat exchanger section into the external connecting passage;
(h) at least one aperture through the inner shell in the first heat exchanger section through which the second fluid flows from the external connecting passage into the first heat exchanger section;
wherein said at least one aperture in the first heat exchanger section comprises a first axial gap which is provided between a first portion of the inner shell wall and a second portion of the inner shell wall;
wherein the second heat exchanger section comprises a concentric tube heat exchanger comprising:
(i) an axially extending intermediate tube which is at least partially received within the first portion of the inner shell wall and is spaced therefrom so that an outer annular space is provided between the inner shell wall and the intermediate tube, wherein the outer annular space comprises part of the second fluid flow passage and is located between the second fluid inlet and the at least one aperture through the inner shell in the second heat exchanger section through which the second fluid flows from the second heat exchanger section into the external connecting passage;
(ii) an axially extending inner tube received within the intermediate tube and spaced therefrom so that an inner annular space is provided between the inner tube and the intermediate tube, wherein the inner annular space comprises part of the first fluid flow passage, and is located between the internal connecting passage and the first fluid outlet, and wherein at least one end of the inner tube is closed in order to prevent fluid flow therethrough;
wherein the first heat exchanger section comprises a shell and tube heat exchanger, comprising:
(a) a first plurality of axially extending, spaced apart tubes enclosed within the inner shell, each of the tubes of the first plurality having a first end, a second end and a hollow interior, the first and second ends being open; wherein the hollow interiors of the first plurality of tubes together define part of the first fluid flow passage;
(b) a first header having perforations in which the first ends of the first plurality of tubes are received in sealed engagement, wherein the first header has an outer peripheral edge which is sealingly secured to the inner shell wall;
(c) a second header having perforations in which the second ends of the first plurality of tubes are received in sealed engagement, wherein the second header has an outer peripheral edge which is sealingly secured to the inner shell wall, wherein a space enclosed by the inner shell and the first and second headers defines part of the second fluid flow passage;
wherein the first header is attached to the first portion of the inner shell and the second header is attached to the second portion of the inner shell, such that the first axial gap between the first and second portions of the inner shell wall provides communication between the external connecting passage and the space enclosed by the inner shell and the first and second headers;
wherein the second fluid outlet comprises an aperture through the inner shell wall and is located between the first header and the second header, wherein the first header and the second fluid outlet are located proximate to the first end of the inner shell;
wherein the first heat exchanger section further comprises a first baffle plate extending across the space enclosed by the inner shell and the first and second headers and dividing said space into a first portion and a second portion;
wherein the first baffle plate has an outer peripheral edge which is close to or in contact with the inner shell wall, a plurality of perforations through which the first plurality of tubes extend, and an aperture which provides communication between the first and second portions of said space;
wherein the outer peripheral edge of the first baffle plate is sealingly secured to the inner shell wall;
wherein the second fluid outlet is located in the first portion of said space;
wherein the first heat exchanger section further comprises a second baffle plate having an axially extending tubular side wall having a hollow interior and which is open at both ends;
wherein the second baffle plate is located within the first portion of said space and extends axially between the first baffle plate and the first header;
wherein one end of the second baffle plate abuts the first baffle plate with the tubular side wall of the second baffle plate surrounding the aperture of the first baffle plate such that the aperture of the first baffle plate communicates with the hollow interior of the tubular side wall of the second baffle plate; and
wherein the tubular side wall of the second baffle plate has at least one aperture providing communication between the hollow interior of the second baffle plate and the second fluid outlet.

2. The heat exchange device of claim 1 , wherein the first baffle plate is a flat, annular plate and extends transversely across the space enclosed by the inner shell and the first and second headers, wherein the aperture through the first baffle plate is located in a central portion of the first baffle plate, and wherein the first baffle plate is located approximately midway between the first and second headers.

3. The heat exchange device of claim 1 , wherein the at least one aperture in the tubular side wall of the second baffle plate faces away from the aperture defining the second fluid outlet.

4. The heat exchange device of claim 3 , wherein the aperture in the tubular side wall of the second baffle plate comprises an axially extending slot.

Assignees

• Dana Canada Corp

Inventors

• Vanderwees Doug
• Hasan Manaf
• Huang Jianan
• Cheadle Brian E

Classifications

• F28D7/16

  the conduits being arranged in parallel spaced relation ({F28D7/0008 - F28D7/0058 take precedence}; F28D7/02 - F28D7/10 take precedence) · CPC title

• F28F9/00 Primary

  Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings · CPC title

• F28F2265/26

  for allowing differential expansion between elements · CPC title

• F28D2021/0024

  for combustion apparatus, e.g. for boilers · CPC title

• F22B9/04

  the fire tubes being in upright arrangement · CPC title