Title of Invention	"A DENSE FLUIDIZED BED EXCHANGER".
Abstract	A dense fluidized bed exchanger comprising a casing (1) the vertical longitudinal walls (1A, 1B) of which consist of tubes conveying a heat conducting fluid and divided lengthwise into chambers separated from each other by a baffle (10) consisting of a wall consisting of tubes conveying a heat-conducting fluid, characterized in that said vertical longitudinal walls (1A, 1B) consist of horizontal tubes (11A, 11B, 12A, 12B) and said baffle extends from the bottom wall of the casing (1) to a height less than that of the latter and consists of superposed hairpin-shape transverse extensions of tubes (HA, 11B) of each of the vertical longitudinal walls (1A, 1B) perpendicular to said tubes and extending to the opposite vertical longitudinal wall (1B, 1A).

Title of Invention

"A DENSE FLUIDIZED BED EXCHANGER".

Abstract

A dense fluidized bed exchanger comprising a casing (1) the vertical longitudinal walls (1A, 1B) of which consist of tubes conveying a heat conducting fluid and divided lengthwise into chambers separated from each other by a baffle (10) consisting of a wall consisting of tubes conveying a heat-conducting fluid, characterized in that said vertical longitudinal walls (1A, 1B) consist of horizontal tubes (11A, 11B, 12A, 12B) and said baffle extends from the bottom wall of the casing (1) to a height less than that of the latter and consists of superposed hairpin-shape transverse extensions of tubes (HA, 11B) of each of the vertical longitudinal walls (1A, 1B) perpendicular to said tubes and extending to the opposite vertical longitudinal wall (1B, 1A).

Full Text	The present invention relates to a dense fluidized bed exchanger. The present invention concerns a dense fluidized bed exchanger to be associated with a circulating f lu-idized-bed-reactor•. - - - . ,It is more precisely concerned with a dense fluidized bed exchanger including a casing the vertical longitudinal walls of which consist of tubes conveying a heat-conducting fluid and divided lengthwise into chambers separated from each other by a baffle consisting of tubes conveying a heat-conducting fluid. An exchanger of the above kind is generally intended for use in a combustion installation comprising a circulating fluidized bed exchanger having a gas outlet leading into a separator cyclone. The solids recovered from the latter are treated in the dense fluidized bed before at least some of them are re-injected into the circulating fluidized bed exchanger. A conventional dense fluidized bed exchanger includes a number of chambers in a casing: - a solids receiving chamber into which solids are introduced via an orifice, - at least one intermediate chamber into which the solids overflow after passing over a first baffle, and - a solids outlet chamber receiving the solids after they pass over a second baffle and having a solids evacuation orifice. The intermediate chamber is equipped with a bottom fluidizing air feed casing, fluidizing air injector nozzles on the bottom wall of the chamber and a heat exchanger generally consisting of a plurality of parallel arrangements of tubes conveying a heat-conducting fluid, for example steam, disposed transversely to the chamber and suspended from the top wall of the chamber, each arrangement of tubes being connected at the bottom to a heat-conducting fluid inlet manifold and at the top to a heated fluid outlet manifold. Dense fluidization of the solids and recovery of heat by the exchanger therefore take place in this chamber. • - - Making the longitudinal walls of the casing and the baffles of tubes conveying a heat-conducting fluid for enhanced heat exchange, heat recovery and thus installation efficiency is known in itself. In the prior art these baffles are walls of vertical tubes extending the full height of the casing and including windows distributed across their width at the required overflow height. This overflow arrangement does not allow solids to overflow across the full width of the casing and because the windows must be of limited width, given the continuity of the vertical tubes from the bottom of the wall to its top, this arrangement does not allow continuous and optimal flow of the solids from one chamber to the other. The invention solves this problem by, proposing a baffle arrangement consisting of tubes that can be made to a given height and thus allow continuous and undisturbed overflowing of the solids over the baffle. To achieve this, in accordance with the invention, said vertical longitudinal walls consist of horizontal tubes and said baffle consists of superposed transverse ,hairpin-shape extensions of tubes of each of the vertical longitudinal walls perpendicular to said tubes and extending to the opposite vertical longitudinal wall. It is therefore possible to make a baffle of the "required height. In the preferred embodiment the extensions alternate vertically from one side to the other to procure mechanical stability and a balanced flow of theheat-conducting fluid. To provide hydrostatic strength the baffle consisting of a double tubed wall is preferably internally reinforced with bracing members. In --a pr-ef-erjred embodiment-alternate- -tubes- of -each vertical wall include an extension of the above kind directed towards the other wall and an extension of the "other wall that is in the same horizontal plane as the tube of . the other wall not having any extension is interleaved between two such extensions. The top part of the baffle is advantageously chamfered with a reducing section.The present invention relates to a dense fluidized bed exchanger comprising a casing (1) the vertical longitudinal walls (1A, 1B) of which consist of tubes conveying a heat conducting fluid and divided lengthwise into chambers separated from each other by a baffle (10) consisting of a wall consisting of tubes conveying a heat-conducting fluid, characterized in that said vertical longitudinal walls (1A, 1B), consist of horizontal tubes (11A, 11B, 12A, 12B) and said baffle extends from the bottom wall of the casing (1) to a height less than that of the latter and consists of superposed hairpin-shape transverse extensions of tubes (11A, 11B) of each of the vertical longitudinal walls (1A, 1B) perpendicular to said tubes and extending to the opposite vertical longitudinal wall (1B, 1A). The invention is described hereinafter in more detail with the aid of drawings showing a preferred embodiment of the invention. Figure 1 is a schematic perspective sview -of a dense fluidized bed'exchanger casing. Figure 2 is a detail perspective view of an exchanger in accordance with the invention. Figure 3 is a part-sectional view taken along the line II-II in figure 2. Figure 4 is a partly cut away perspective view of an exchanger in accordance with the invention. A conventional dense fluidized bed exchanger as shown diagrammatically in figure 1 includes a number of chambers inside a casing 1: - a solids receiving chamber 2 into which solids are introduced via an orifice 3, - at least one chamber 4, 5 into which the solids overflow after passing over a first baffle 10A and separated from each other by a baffle 10B of the same type, and - a solids outlet chamber 6 receiving the solids after they have passed over another baffle IOC and including a solids evacuation orifice 7. As can be seen in figure 2, in accordance with the invention, the vertical longitudinal walls 1A, 1B consist of horizontal tubes 11A, 12A and 11B, 12B. The baffle 10 consists of superposed transverse hairpin-shape extensions-of- tubes 11A,—11B of-each of the vertical longitudinal walls 1A, 1B perpendicular to said tubes and extending to the opposite vertical longitudinal wall 1B, 1A. To be more precise, alternate tubes 11A, 11B of each vertical wall 1A, 1B include an extension of this kind directed towards the other wall 1B, 1A. An extension of the other wall 1B, 1A interleaved between two such extensions is in the same horizontal plane as the tube 12A, 12B of the other wall 1A, 1B that does not have any extension. .V4 [ The top part of the baffle 10 is chamfered with a .reduc In this way a constant pitch between tubes is btained, both in the vertical walls and in the baffle, Without~any intersection of tubes. i Conventional metal fins close the walls of tubes 1 J'ormed in this way, linking all the adjacent tubes, and the baffle is covered externally with a layer of concrete 13 (figure 3). The tube structure is mechanically strengthened by bracing members disposed inside the baffle. The top part of the baffle 10 is shown in cross-section in figure 3. A top bracing member 14 is shown in figure 3. It is a bar welded between the two branches of the hairpin shape of an extension. Such bracing members 14 are distributed over the height of the top part and over the width of the baffle to obtain the require mechanical stability. As shown in figure 4, bracing members distributed across the width of the bottom part of the baffle 10 provide mechanical stability and the connection to the bottom wall of the casing. This bottom wall, also known as the sole plate, also -comprises nori-zontal- tubes r--to -be-mor-e--precise -a -tep wall 15 consisting of tubes linked by horizontal fins. Another tube 16 is connected to the bottom of each tube of this wall by a vertical fin 17. Two tie-rods 18 level with the baffle and longitudinal thereof are welded to the sole plate, passing through the vertical fins 17. The tie-rods 18 are connected to bracing members 19 having a maximal height equal to the height of the constant section part of the baffle and consisting of a plate or the like with lateral notches receiving the tubes of the extensions. WE CLAIM: 1. A dense fluidized bed exchanger comprising a casing (1) the vertical longitudinal walls (1A, 1B) of which consist of tubes conveying a heat conducting fluid and divided lengthwise into chambers separated from each other by a baffle (10) consisting of a wall consisting of tubes conveying a heat-conducting fluid, characterized in that said vertical longitudinal walls (1A, 1B) consist of horizontal tubes (11A, 11B, 12A, 12B) and said baffle extends from the bottom wall of the casing (1) to a height less than that of the latter and consists of superposed hairpin- shape transverse extensions of tubes (11A, 11B) of each of the vertical longitudinal walls (1A, 1B) perpendicular to said tubes and extending to the opposite vertical longitudinal wall (1B, 1A). 2. A dense fluidized bed exchanger as claimed in claim 1, wherein the extensions alternate vertically from one wall to the other. 3. A dense fluidized bed exchanger as claimed in claim 1 or claim 2 wherein the baffle consisting of a doubled tubed wall is reinforced internally with bracing members (14, 19). 4. A dense fluidized bed exchanger as claimed in claim 2, wherein alternate tubes (11A, 1 1B) of each vertical wall (1A, 1B) has an extension of the above kind directed towards the other wall (1B, 1A) and in that an extension of the other wall (1B, 1A) interleaved between two such extensions is in the same horizontal plane as the tube (12A, 12B) of the other wall (1A, 1B) not including any extension. 5. A dense fluidized bed exchanger as claimed in anyone of the preceding claims wherein the top part of the baffle is chamfered with a reducing section. 6. A dense fluidized bed exchanger substantially as herein described with reference to the accompanying drawings.

Full Text

The present invention relates to a dense fluidized bed exchanger.
The present invention concerns a dense fluidized bed exchanger to be associated with a circulating
f lu-idized-bed-reactor•. - - -
. ,It is more precisely concerned with a dense fluidized bed exchanger including a casing the vertical longitudinal walls of which consist of tubes conveying a heat-conducting fluid and divided lengthwise into chambers separated from each other by a baffle consisting of tubes conveying a heat-conducting fluid.
An exchanger of the above kind is generally intended for use in a combustion installation comprising a circulating fluidized bed exchanger having a gas outlet leading into a separator cyclone. The solids recovered from the latter are treated in the dense fluidized bed before at least some of them are re-injected into the circulating fluidized bed exchanger.
A conventional dense fluidized bed exchanger includes a number of chambers in a casing:
- a solids receiving chamber into which solids are
introduced via an orifice,
- at least one intermediate chamber into which the
solids overflow after passing over a first baffle, and
- a solids outlet chamber receiving the solids
after they pass over a second baffle and having a solids
evacuation orifice.
The intermediate chamber is equipped with a bottom fluidizing air feed casing, fluidizing air injector nozzles on the bottom wall of the chamber and a heat exchanger generally consisting of a plurality of parallel arrangements of tubes conveying a heat-conducting fluid, for example steam, disposed transversely to the chamber and suspended from the top wall of the chamber, each arrangement of tubes being connected at the bottom to a
heat-conducting fluid inlet manifold and at the top to a heated fluid outlet manifold.
Dense fluidization of the solids and recovery of
heat by the exchanger therefore take place in this
chamber. • - -
Making the longitudinal walls of the casing and the baffles of tubes conveying a heat-conducting fluid for enhanced heat exchange, heat recovery and thus installation efficiency is known in itself.
In the prior art these baffles are walls of vertical tubes extending the full height of the casing and including windows distributed across their width at the required overflow height.
This overflow arrangement does not allow solids to overflow across the full width of the casing and because the windows must be of limited width, given the continuity of the vertical tubes from the bottom of the wall to its top, this arrangement does not allow continuous and optimal flow of the solids from one chamber to the other.
The invention solves this problem by, proposing a baffle arrangement consisting of tubes that can be made to a given height and thus allow continuous and undisturbed overflowing of the solids over the baffle.
To achieve this, in accordance with the invention, said vertical longitudinal walls consist of horizontal tubes and said baffle consists of superposed transverse
,hairpin-shape extensions of tubes of each of the vertical

longitudinal walls perpendicular to said tubes and
extending to the opposite vertical longitudinal wall.
It is therefore possible to make a baffle of the "required height.
In the preferred embodiment the extensions alternate vertically from one side to the other to procure mechanical stability and a balanced flow of theheat-conducting fluid.
To provide hydrostatic strength the baffle consisting of a double tubed wall is preferably internally reinforced with bracing members.
In --a pr-ef-erjred embodiment-alternate- -tubes- of -each vertical wall include an extension of the above kind directed towards the other wall and an extension of the "other wall that is in the same horizontal plane as the tube of . the other wall not having any extension is interleaved between two such extensions.
The top part of the baffle is advantageously chamfered with a reducing section.The present invention relates to a dense fluidized bed exchanger comprising a casing (1) the vertical longitudinal walls (1A, 1B) of which consist of tubes conveying a heat conducting fluid and divided lengthwise into chambers separated from each other by a baffle (10) consisting of a wall consisting of tubes conveying a heat-conducting fluid, characterized in that said vertical longitudinal walls (1A, 1B), consist of horizontal tubes (11A, 11B, 12A, 12B) and said baffle extends from the bottom wall of the casing (1) to a height less than that of the latter and consists of superposed hairpin-shape transverse extensions of tubes (11A, 11B) of each of the vertical longitudinal walls (1A, 1B) perpendicular to said tubes and extending to the opposite vertical longitudinal wall (1B, 1A).
The invention is described hereinafter in more detail with the aid of drawings showing a preferred embodiment of the invention.
Figure 1 is a schematic perspective sview -of a dense fluidized bed'exchanger casing.
Figure 2 is a detail perspective view of an exchanger in accordance with the invention.
Figure 3 is a part-sectional view taken along the line II-II in figure 2.
Figure 4 is a partly cut away perspective view of an exchanger in accordance with the invention.
A conventional dense fluidized bed exchanger as shown diagrammatically in figure 1 includes a number of chambers inside a casing 1:
- a solids receiving chamber 2 into which solids
are introduced via an orifice 3,
- at least one chamber 4, 5 into which the solids
overflow after passing over a first baffle 10A and
separated from each other by a baffle 10B of the same
type, and
- a solids outlet chamber 6 receiving the solids
after they have passed over another baffle IOC and
including a solids evacuation orifice 7.
As can be seen in figure 2, in accordance with the invention, the vertical longitudinal walls 1A, 1B consist of horizontal tubes 11A, 12A and 11B, 12B.
The baffle 10 consists of superposed transverse hairpin-shape extensions-of- tubes 11A,—11B of-each of the vertical longitudinal walls 1A, 1B perpendicular to said tubes and extending to the opposite vertical longitudinal wall 1B, 1A.
To be more precise, alternate tubes 11A, 11B of each vertical wall 1A, 1B include an extension of this kind directed towards the other wall 1B, 1A. An extension of the other wall 1B, 1A interleaved between two such extensions is in the same horizontal plane as the tube 12A, 12B of the other wall 1A, 1B that does not have any extension.
.V4
[ The top part of the baffle 10 is chamfered with a .reduc
In this way a constant pitch between tubes is
btained, both in the vertical walls and in the baffle, Without~any intersection of tubes.
i Conventional metal fins close the walls of tubes 1 J'ormed in this way, linking all the adjacent tubes, and the baffle is covered externally with a layer of concrete 13 (figure 3).
The tube structure is mechanically strengthened by bracing members disposed inside the baffle.
The top part of the baffle 10 is shown in cross-section in figure 3.
A top bracing member 14 is shown in figure 3. It is a bar welded between the two branches of the hairpin shape of an extension. Such bracing members 14 are distributed over the height of the top part and over the width of the baffle to obtain the require mechanical stability.
As shown in figure 4, bracing members distributed
across the width of the bottom part of the baffle 10 provide mechanical stability and the connection to the bottom wall of the casing.
This bottom wall, also known as the sole plate, also -comprises nori-zontal- tubes r--to -be-mor-e--precise -a -tep wall 15 consisting of tubes linked by horizontal fins. Another tube 16 is connected to the bottom of each tube of this wall by a vertical fin 17. Two tie-rods 18 level with the baffle and longitudinal thereof are welded to the sole plate, passing through the vertical fins 17. The tie-rods 18 are connected to bracing members 19 having a maximal height equal to the height of the constant section part of the baffle and consisting of a plate or the like with lateral notches receiving the tubes of the extensions.

WE CLAIM:
1. A dense fluidized bed exchanger comprising a casing (1) the
vertical longitudinal walls (1A, 1B) of which consist of tubes conveying a
heat conducting fluid and divided lengthwise into chambers separated
from each other by a baffle (10) consisting of a wall consisting of tubes
conveying a heat-conducting fluid, characterized in that said vertical
longitudinal walls (1A, 1B) consist of horizontal tubes (11A, 11B, 12A,
12B) and said baffle extends from the bottom wall of the casing (1) to a
height less than that of the latter and consists of superposed hairpin-
shape transverse extensions of tubes (11A, 11B) of each of the vertical
longitudinal walls (1A, 1B) perpendicular to said tubes and extending to
the opposite vertical longitudinal wall (1B, 1A).
2. A dense fluidized bed exchanger as claimed in claim 1, wherein the
extensions alternate vertically from one wall to the other.
3. A dense fluidized bed exchanger as claimed in claim 1 or claim 2
wherein the baffle consisting of a doubled tubed wall is reinforced
internally with bracing members (14, 19).
4. A dense fluidized bed exchanger as claimed in claim 2, wherein
alternate tubes (11A, 1 1B) of each vertical wall (1A, 1B) has an
extension of the above kind directed towards the other wall (1B, 1A) and in that an extension of the other wall (1B, 1A) interleaved between two such extensions is in the same horizontal plane as the tube (12A, 12B) of the other wall (1A, 1B) not including any extension.
5. A dense fluidized bed exchanger as claimed in anyone of the
preceding claims wherein the top part of the baffle is chamfered with a
reducing section.
6. A dense fluidized bed exchanger substantially as herein described
with reference to the accompanying drawings.

Documents:

624-del-1998-abstract.pdf

624-del-1998-claims.pdf

624-del-1998-correspondence-others.pdf

624-del-1998-correspondence-po.pdf

624-del-1998-description (complete).pdf

624-del-1998-drawings.pdf

624-del-1998-form-1.pdf

624-del-1998-form-19.pdf

624-del-1998-form-2.pdf

624-del-1998-form-3.pdf

624-del-1998-form-4.pdf

624-del-1998-form-6.pdf

624-del-1998-form-gpa.pdf

« Previous Patent

Next Patent »

Patent Number

213041

Indian Patent Application Number

0624/DEL/1998

PG Journal Number

01/2008

Publication Date

04-Jan-2008

Grant Date

19-Dec-2007

Date of Filing

11-Mar-1998

Name of Patentee

GEC ALSTHOM STEIN INDUSTRIE

Applicant Address

19-21, AVENUE MORANE SAULNIER 78140 VELIZY - VILLACOUBLAY FRANCE

Inventors:

#	Inventor's Name	Inventor's Address
1	ALAIN QUARANTA	10 RUE DES VIGNES, 91640 FONTENAYLESS BRIS, FRANCE
2	DJAMEL DAOUD	69 BOULEVARD DE GRENELE, 75015 PARIS FRANCE
3	JEAN A UBRY	26 RUE PAUL RIVET 92350 LE PLESSIS ROBINSON, FRANCE

PCT International Classification Number

B09B 3/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	9702991	1997-03-13	France