Process and device of recovery of heat in fluidization.

AS AFRICAN AND MALAGASY

INDUSTRIAL PROPERTY

P. 887

Yaounde (Cameroon) Patent International Patent Classification: 21 - b 01 no. 00389 C.

l-o.Cm ^ P.I.

JVBE1 TD

20 October 1964 to 15 hr 51 requested Mn to the O.A.M.P.I. (G.P. no. 50,465) by Institute of searches of steel production French, residing in France.

Delivered 15 May 1966, published at Official ballot n° 4/5 of 1966. Priority: Patent application filed in France under the n° G.P. 934,749 14 May 1963 on behalf of the requester.

Method and apparatus for heat recovery in fluidization.

The present invention relates to a method and a DIS -

positive for transferring heat sensitive materials - sweater

cold vérulentes to powdered materials.

Known methods and devices for in obtaining -

a NIR such transfer of heat between solid particles

employ conventional heat exchangers - exa

killed by an enclosure through a tube bundle.

It is fluidized powdered materials in the enclosure

while current is passing into the tube bundle a

gas stream carrying with it - pulvéru materials

slow that are at a temperature different from the first.

As the heat propagates better between the advantage -

coated nanoparticles a mass fluidized particles in that between

pneumatic conveyance has been to improve the image display apparatus -

dice from heat exchange between pulverulent materials

by fluidizing the material in the tubes of a heat exchanger.

For this directing pipes vertically, is introduced

the loose material at their upper ends

and a fluidizing gas at their lower ends

to form in each tube a column

fluidized materials subjected to current - renews

telling a top to bottom.

This latter method, as the rest of the previous

from which it is at the bottom that alternatively, present some

disadvantages inherent when a bundle of tubes.

It is, indeed, very difficult to distribute equally

quantities of substances passing through the tubes, inequalities in

distribution does not lack occurring and the on -

face techangor is then incompletely used. It

even reaches, when it is desired to implement the second

method recited, such as to a flow regime

particular according to which the fluidizing gas through

some tubes into which the materials do not penetrate

, or shortly while passing through other tubes quickly

, - ' j in which the fluidizing gas does then pass

-11 more nearly, so that certain tubes arrive even at

The XY■<- clog.

The present invention aims to remedy these

drawbacks and achieve a simple and low

expensive heat transfer between materials sweater -

vérulentes hot and cold in order to improve the thermal budget of any processing operation in which the materials are to be processed cold and hot at the end of which it is thereby hot powder materials.

To this end, the present invention provides a method for transferring a portion of the sensible heat of pulverulent materials in powder form hot to cold, the method in which a fluidized beds separate hot and cold materials by means of at least one gas flow vertically, characterized in that is established within fluidizing beds horizontal flows of powder and moving along at least one substantially vertical partition separating said material beds hot and cold materials, said horizontal flows moving buckets being established by supplying and discharging continuous materials in powder form in areas separated by a horizontal distance as large as possible and substantially parallel to said partition.

The method may also include one or more of the following features:

has. The hot material flows along said wall in reverse cold materials;

b.. In using a common gas stream for fluidizing successively the various beds of powder materials, gas stream of hot material advantageously from cold materials;

c.. At least one of said fluidizing gas streams for said powder material is from a processing plant in fluidization from where said hot material and wherein said cold materials are treated after preheated according to the above method.

The present invention also relates to a device for implementing the above method in an enclosure provided with means known for the withdrawing powder materials as well as means for fluidizing the, device characterized in that said enclosure is divided into several compartments by at least one partition substantially vertical inner, in that each compartment is provided with fluidizing means separately from powder materials by gas flow vertical and means for discharging said gas stream vertically and also with means for withdrawing or powder materials, and that the horizontal projection of the path from, in each compartment, said means for introducing powdered materials to said means for discharging said powder materials, is substantially parallel to and equal to the length of said partition.

The device may also include one or more of the following features:

а. For carrying out the above process according to its characteristic has, the path from, in a compartment, said means for introducing powdered materials to said means for removing these same materials is parallel and opposed to the corresponding path through the neighboring compartment;

б. For carrying out the above process according to its characteristic b., a line connects said means for vertical exhaust gas stream at least one of said compartments to said means for fluidization of the neighboring compartment;

c.. For carrying out the above process according to its characteristic C., said discharge means of powdered material from at least one of said compartments and said means for introducing powdered materials in at least an adjacent compartment each comprise a conduit connected to a treatment plant in fluidizing and further said fluidizing powder in at least one of said compartments are connected by a conduit to the outlet of the fluidizing gas that facility;

th. The contour of said enclosure is a rectangular quadrilateral;

/. Said enclosure is according to E above and is divided into three compartments by two partitions as quadrangular outline D. above, it is to say parallel to one of its sides.

In order to properly make include the invention, going in describe examples will not limiting implementation by referring to the accompanying drawings in which:

Figure 1 schematically shows in vertical section a device according to the invention, for transferring the sensible heat of pulverulent materials in powder form hot to cold;

Figure 2 illustrates the direction of circulation of the powder materials in the device of Figure 1, represented in plane in a horizontal section xX;

Figure 3 represents the branching pattern of compartments 24 and 25 of a exchanger according to the invention, connected to a process reactor fluidizing;

Figure 4 represents a plan view in section on x-X two-compartment of the exchanger 24 and 25 of Figure 3;

Figure 5 represents a variant of the branching pattern of a device similar to that of Figure 3. Figures 1 and 2, is shown a parallelepipedic enclosure 1 of rectangular horizontal section (Figure 2). This enclosure is separated into three compartments 2, 3, 4 by two vertical metal plates 5 and 6.

Each of these compartments is provided with means for fluidization, it is to say, for the compartment 2, a gas inlet, a fluidization grid 8 and a gas outlet 9. Identical means β 7, 8has, 9a, ; 1b, 86, 96 fall respectively in the compartments 3 and 4.

Distributor pipes powdered materials] either 10, 11 and 12, respectively emerge to extré -.

mites compartments above gates 8, 8®, 86.^;

The opposite ends of the compartments and nor - ' upper calves are located the flared mouths 13, 14, 15 of discharge lines 13®, 14®, 15®powder materials.

This exchanger receives, of any type processing, materials in powder form hot incoming from the pipe 11 into the compartment 3 where they are fluidized by a gas stream vertically (dashed arrows) from the same processing plant. These materials are discharged to the exterior of the device via pipe 14 so builds up within the fluidizing bed in 3 a current general displacement of the materials in the horizontal direction (arrows 16 in continuous lines).

The fluidizing gas leaving the compartment 3 via a pipe 17 connected to the opening 9a, and then pass through a dust removal "cyclonic" 18 and are then supplied by a conduit 19 in 7 and 76, under the grates fluidizing compartments 2 and 4 through which they pass vertically to be further discharged outside by a conduit 20 to a cyclone 21 after dedusting.

The loose material cold to be preheated before processing 10 and 12 are introduced into the compartments 2 and 4, and then fluidized and move horizontally as indicated by arrows 22 to the openings 13 and 13®15a and 15 lines which are connected to the proper place of the process plant.

The heat sensitive materials fluidized with the 3 passes, through the plates 5 and 6, in the fluidizing beds 2 compartments 4 and in which the materials to be treated flow in countercurrent and further receives a large part of the sensible heat of the fluidizing gas to separate.

Figure 3 schematically shows the branch in a process plant having a reactor 23 magnetizing roasting ore powder and an exchanger with two compartments 24 and 25. The two compartments are, for ease of illustration, shown separately in Figure 3, but are in fact part of a single enclosure donations Figure 4 represents a plan view in section on VI-VI, and are separated only by a vertical sheet 26 through which transfer the heat.

The ore to be treated is from a reserve 27. A screw feeder 28 the introduces in the compartment 24 of the exchanger where it is fluidized and preheated, and then it arrives by a pipe 29 in the roasting reactor 23 where it is simultaneously fluidized and blown by hot gas leaking from a combustion chamber 30 immersed in the bed of materials, and fed with air and fuel oil supplied by