AU632407B2

AU632407B2 - Reactor

Info

Publication number: AU632407B2
Application number: AU73645/91A
Authority: AU
Inventors: Owen Edward Jones
Original assignee: BLACKWALL REACH NOMINEES Pty Ltd
Current assignee: BLACKWALL REACH NOMINEES Pty Ltd
Priority date: 1990-03-21
Filing date: 1991-03-20
Publication date: 1992-12-24
Anticipated expiration: 2011-03-20
Also published as: AU7364591A

Description

1" 632407 COMMONWEALTH OF AUSTRALIA Patents Act 1952 COMPLETE SPECIFICATION (Original) FOR OFFICE USE Application Number: PJ9211 Lodged: 21/3/90 Complete Specification Lodged: Accepted: Published: -Priority: Related Art: Class Int. Class a s04 0 0 0 o a 000 o 0o 0 0 0n o 0 0 0 0 o 0 TO BE COMPLETED BY APPLICANT o 0 0 0 0 0 0 0 0 0 4 Name of Applicant: Address of Applicant: Actual Inventor: Address for Service:- BLACKWALL REACH NOMINEES PTY LTD 10 Blackwall Reach Parade, Bicton in the State of Western Australia, Commonwealth of Australia.

OWEN EDWARD JONES Wray Associates Primary Industry House 239 Adelaide Terrace Perth Western Australia 6000, Complete Specification for the invention entitled:

"REACTOR"

The following statement is a full description of this invention, including the best method of performing it known to me:- ~e~ 1 i a, r~s~~t=t PJ vv vi I 2- THIS INVENTION relates to a reactor and in particular a reactor which may be utilised to effect the processing of reactant materials which require an endothermic reaction at raised temperatures in order to be processed.

In one form the invention resides in a reactor comprising a substantially tubular passageway having a plurality of zones defined along its length wherein each zone has an injection means for introduction of air and fuel into the passageway, said injection means being arranged to create a vortex within each zone whereby there is a nett controlled axial flow through each zone from one end of the passagewayi control means, to control the delivery of air and fuel to each zone to control the conditions in each zone and delivery means for delivering a reactant to said one end of said passageway.

The invention will be more fully understood in the light of the following description of two specific embodiments.

The description is made with reference to the accompanying drawings of which; Figure 1 is a schematic representation of a reactor according to the first embodiment; and Figure 2 is a schematic representation of a reactor according to the second embodiment.

The embodiments can be used for the processing of materials which require an endothermic reaction at raised temperatures in order to be processed. Such materials may conprise the waste products of mineral processing and particular examples of such materials comprise sodium oxalate and red mud which are the waste products of the processing of bauxite into alumina.

-3- The reactor of the first embodiment as shown at Figure 1 comprises a substantially tubular passageway 11 which in E the case of the first embodiment is subdivided into four separate zones A, B, C, and D which are substantially colinear. The walls of the passageway are formed of a suitable refractory and the walls of each zone have embedded therein one or more tubular coils 13. Both ends of each coil are connected to a separate inlet 14 (although only one inlet is shown) associated with each coil. Each coil is provided with a series of spaced apertures on their inner face which open into ports o°o provided in the refractory walls 12 of the respective zone. The ports 15 are directed substantially obliquely 0o to the radial axis of the zones in a common direction.

Each inlet 14 is connected to a fuel inlet 16 and an air 0°o inlet 17. The air inlet 17 may be associated with a 0o regulator 18 in order to increase the pressure of the air being delivered into the coils 13. A suitaole ignition means is provided within the tubular body 11 such that on the introduction of the air fuel mixtures into each zone o such air fuel mixtures can Le ignited. As a result of the .o direction of injection of the air fuel mixture into the tubular body 11 and the increased pressure resulting from the ignition thereof a high speed vortex is created within the tubular body 11. The effect of the vortex not only causes the circular movement of the combustion reactants and products within the tubular body 11 but also causes a controlled nett axial movement of such combustion reactants and products through the zone. The degree of axial movement can be controlled by the orientation and location of the ports 15 in each zone whereby the net axial flow through the tubular body may be substantially uniform or alternatively may vary from zone to zone. Each zone may be associated with suitable flame monitors and pilot burners to ensure control of the flame conditions within each zone and to ensure maintenance of combustion within each zone. The array of the ports u alin the walls mmmm.. h.m 4 of the refractory may take any desirable form and in particular may take a form whereby the ports define a set of axial rows of ports spaced circumferentially around the interior of the walls of the refractory 12 or alternatively may comprise a plurality of helical arrays of ports in the walls. In addition, if desired the fuel and air can be injected separately into each of the zones by utilisaticn of separate coils. Furthermore the ports may comprise a sub set of ports which are directed substantially radially into the zone in order that air and fuel are injected radially into the vortex to provide for o*o maintenance of high temperature conditions at the centre co°o of the vortex.

0o 0 t ooo The effect of the injection of the fuel and air mixture 00 0O o o tangentially from the walls serves to create a relatively 0o° cool blanket around the interior of the walls 11 which serves to limit the degree of erosion or scavenging of the interior of the walls and also serves to limit the contact of any combustion products or reactants or reaction 0 20 products with the walls.

The reactor of the first embodiment has an inlet 19 from oa o So which the nett axial flow of the vortex moves. The inlet is connected to a source of air 20 and a venturi-like entrainment means 21 into which the reactant material is delivered from a hopper 22 or like containment means through a screw feed or like delivery means. The entrained reactant material is carried into the reactor to enter the vortex and be carried thereby serially through each of the zones A, B, C and D. By controlling the temperature of the flame in each zone the nature of the reaction induced upon the reactant can be varied in accordance with the chemistry of the reaction. In the case of a reaction process which is a multi-stage reaction, conditions within the zones can be controlled to provide for each reaction stage. In addition where a L 5 reaction stage involves the addition of a further reactant that reactant can be introduced at that stage by the incorporation of an additional coil having a separate inlet 24 for the injection of that further reactant (see zones B and D).

On exiting the tubular passage 11 through the outlet the combustion products and reaction products are passed through a separation means which can take the form of a cyclonic separator 26 to allow for separation of the i'O reaction products. If desired the conditions with the o'o o° cyclonic separator 26 may be such as to inhibit any further reaction (whether it be oxidation or reduction of a0 the reactant products) while being subjected to cooling.

04 no 0 0 S0 The second embodiment of Figure 2 comprises a tubular 00 044 passageway 11 of similar form to that of the first embodiment of Figure 1 and therefore the same reference numerals have been used for similar components. The passageway is subdivided into three axially separate zones A B and C which are substantially co-linear. As in the 0,J 0 20 first embodiment the walls of each zone are defined by a suitable refractory and the walls have embedded therein 0 one or more coils 13 which are connected to an air and fuel inlet and provide an appropriate array of outlet ports 15 into the passageway to produce the desired vortex in the passageway.

The second embodiment however differs from the first I. embodiment in that the reactive material with which the reactor is used is supported within the reaction within a central axial conduit 30. The walls of the conduit are foraminous or perforate and are formed of a material resistant to high temperatures. The upper end of the conduit is associated with an inlet feed hopper 31 or like inlet means while the lower end is associated with an il j I I" 1 6 adjustable discharge outlet 32. The interior of the conduit in the case of the second embodiment supports a spiral flight 33 which can be stationary to allow the reactant material to flow in a spiral fashion down the conduit.

Alternatively the spiral flight 33 can be caused to rotate to positively draw the reactant material down the conduit or alternatively to partially counter the effect of gravity to increase the residence time of the reactant '0O material in the conduit. If desired the spiral flight 33 j B can have differing and/or opposed pitches at each zone p 69 according to the desired residence times of the reactant 0 ,o at each zone whereby the flight can if desired can both 1 0 i aid and impede the flow of material or diff rently aid 00 0 0 0 and/or impede the flow in each zone.

0 0 Where the embodiment is used in heating a readily oxidisable reactant such as carbon, steam and/or an inert gas may be injected at an inlet 34 provided in the lower S"e""U end of the conduit to limit further reaction.

00 0 o 00 0 The reactors of the embodiments may be arranged 0 horizontally, vertically, obliquely or in any desired orientation. Where the reactor is located vertically or obliquely the axial movement of the combustion and a 0 i ,4 4 reaction products through the tubular body may be assisted 0' by gravity or against gravitational forces.

It should be appreciated that the scope of the present invention need not be limited to the particular scope of the embodiment described above.

i iii i- ii i i- i i -I I I i %ml

Claims

1. A reactor comprising a substantially tubular passageway having a plurality of zones defined along its length wherein each zone has an injection means for introduction of air and fuel into the passageway, said injection means being arranged to crr ate a vortex within each zone whereby there is a net controlled axial flow through each zone from one end of the passageway, control means to control the delivery of air and fuel to each zone to control the conditions in each zone and delivery means for delivering a reactant to said one end of said passageway.

2. A reactor as claimed at claim 1 wherein said zones are substantially co-linear. ooo

3. A reactor as claimed at claim 1 or 2 wherein the o walls of said passageway are formed of a refractory material. I:°

4. A reactor as claimed at any one of the preceding claims wherein said injection means comprises at least one tubular coil embedded in the walls of the passageway and having formed therein a plurality of passageways which 4 open into ports provided in said wall.

5. A reactor as claimed at claim 4 wherein the air fuel mixture is introduced from one tubular coil.

6. A reactor as claimed at claim 4 wherein the air and fuel are injected separately into the passageway from separate coils.

7. A reactor as claimed at any one of claims 4, 5 or 6 wherein additional reactant is delivered from another injection means in at least one zone. -8

8. A reactor as claimed at claim 7 wherein said additional reactant comprises a different material to said reactant.

9. A reactor as claimed at any one of claims 4, 5, 6, 7 and 8 wherein at least some of the ports are directed obliquely to the radial axes of said passageway, said at least some ports being directed in a common direction.

A reactor as claimed at any one of the preceding claims wherein an ignition means is provided with at least one zone.

11. A reactor as claimed at any one of claims 4, 5, 6, 7, 8, 9 or 10 wherein some of the ports are directed substantially radially. O0 0

12. A reactor as claimed at any one of claims 4 to 11 wherein at least some of said ports define a helical array So over the walls of the passageway. 010

13. A reactor as claimed at any one of claims 4 to 12 t ^wherein at least some of said ports define an array in the 0 .form of a set of axial rows of ports in the walls of the passageway.

14. A reactor as claimed at any one of the preceding claims wherein the other end of the passageway opens to a separation means for separation of reaction products.

A reactor as claimed at claim 14 wnerein said separator provides a substantially inert environment for said reaction products.

16. A reactor as claimed at claim 14 or 15 wherein said separator comprises a cyclonic separator. k i II i I -I I I I I 9

17. A reactor as claimed at any one of the preceding claims wherein said passageway concentrically accommodates throughout its length a central passageway and whereby said reactant is delivered at the one end of said central passageway, the walls of said central passageway being foraminous.

18. A reactor as claimed at claim 17 wherein said one end is disposed above the other end of the passageway.

19. A reactor as claimed at claim 17 or 18 wherein the interior of said central passageway accommodates a flow control means for controlling the flow of reactant through the passageway.

A reactor as claimed at claim 19 wherein the flow control device comprises at least one spiral flight.

21. A reactor as claimed at claim 20 wherein said spiral flight is stationary.

22. A reactor as claimed at claim 20 wherein said spiral flight is rotatable within said central passageway and is driven to aid and/or impede the flow of reactant through said zones.

23. A reactor substantially as herein described. a O 9 9O 9 9t 0 «0 0 9* I o 90 00 0 9 0 19 )O o a u a 9 0 0 9 9 0 99 o a 9 90 0 aoa 000 0 0 9, u S II u D a a a 0 a a' DATED this TWENTIETH day of OCTOBER 1992. BLACKWALL REACH NOMINEES PTY LTD Applicant. Wray Associates Perth, Western Australia Patent Attorneys for Applicant. r I