AU720647B2

AU720647B2 - Filter or catalytic-converter device

Info

Publication number: AU720647B2
Application number: AU94207/98A
Authority: AU
Inventors: Anton Theiler
Original assignee: Eder GmbH
Current assignee: Eder Maschinenfabrik & Co KG GmbH
Priority date: 1995-09-18
Filing date: 1998-11-27
Publication date: 2000-06-08
Anticipated expiration: 2016-09-12
Also published as: AU701195B2; AU9420798A; AU1364797A

Description

Our Ref: 710294 P/00/011 Regulation 3:2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT 0.

0 0000 0O S

SO

0**0 0 0s00 0 @0 0 0 *0 .009 00 0 0 Applicant(s): Address for Service: Invention Title: Eder Maschinenfabrik GMBH Co KG 2, Fabrikstr.

D-84048 Mainburg

GERMANY

DAVIES COLLISON CAVE Patent Trade Mark Attorneys Level 10, 10 Barrack Street SYDNEY NSW 2000 Filter or catalytic-converter device The following statement is a full description of this invention, including the best method of performing it known to me:- 5020 The present invention concerns a 'catalyst apparatus through which a fluid medium flows. The present invention concerns catalyst apparatuses in which the fluid medium is brought into contact with a catalytically active surface in order to produce corresponding chemical reactions in the fluid medium.

The main problem with apparatuses of that kind involves as far as possible bringing all of the fluid medium into contact with a surface, while at the same time the flow resistance for the fluid medium is to be minimized.

In accordance with the invention that object is attained in that the apparatus comprises stationary and movable parts, and the fluid medium is so guided that it flows alternately through respective stationary and moved parts of the o. apparatus.

~If this design in accordance with the invention is used as an exhaust gas cleaning device in the exhaust gas system of a piston engine, a further substantial advantage is that the apparatus acts as a sound damper and considerably reduces the •0 exhaust gas noises.

In that respect it is preferred that the movable parts rotate in a cylindrical housing as the drive for the movable parts *0 requires the lowest level of energy expenditure, when the 0- 0movement is a rotating movement. The cylindrical shape of the housing follows from the rotational movement.

In that respect it is further preferred that the axis of rotation of the movable parts is disposed coaxially with respect to the cylindrical shape of the housing. Inthat way the amount of space required for the apparatus can be minimized.

In particular it is preferred that a drive device is disposed at one of the end faces of the cylinder. A preferred embodiment provides that the movable parts are of disk form and that the stationary parts which are arranged therebetween are flat. That provides that the apparatus is of a particularly compact construction.

Preferably a gas intake connection is arranged at the one end of the cylinder and a gas outlet connection is arranged at the opposite end of the cylinder. The flow of the medium in the apparatus is optimised in that way.

In that case the openings may be in respective mutually opposite annular regions of the movable and stationary parts, p.

thereby producing very intensive turbulence in the medium.

A particularly simple manufacturing option for the apparatus *o is achieved by the movable parts being arranged on a common shaft.

•0 9 In accordance with a further preferred embodiment of the invention the movable and stationary parts are in the form of hollow cylinders and are disposed alternately coaxially relative to each other. That provides for a constant relative speed as between the movable parts and the medium flowing through the apparatus.

3 In that case it is preferred for a gas intake connection to be arranged at the periphery of the cylinder and for a gas outlet connection to be arranged at the lower end thereof.

Preferably in this case also the openings are disposed in respective mutually oppositely arranged regions of the movable and stationary parts.

The apparatus is of a particularly simple design configuration if the movable parts which are in the form of hollow cylinders are arranged on a common driven carrier disk.

The apparatuses according to the invention can be particularly economically produced if the stationary and the movable parts are in the form of apertured plates, and in that case particularly advantageous coating with a catalyst material is possible, for example by sputtering.

r A particularly light construction for the apparatuses according to the invention is achieved if the stationary and the movable partsare in the form of grills.

Preferably the drive is an electric motor.

In oder to enhance the efficiency of the apparatus, the stationary and/or the movable parts of the apparatus can be hollow and can be in communication with a feed device for an auxiliary gas.

If the movable parts of the apparatus are hollow, a particularly advantageous specific shape for the outlet openings for the auxiliary gas is one in which they are formed by outward bulge portions which rise in the opposite direction to the direction of rotation and form a rearwardly directed opening. By virtue of that arrangement, an even greater reduced pressure for suction of the auxiliary gas can be generated by virtue of the rotary movement of the movable parts of the apparatus, and at the same time that configuration prevents clogging of the openings with fouling matter.

This apparatus can be embodied in a particularly simple fashion if the auxiliary gas is air.

In a catalyst apparatus the carrier body may be for example in the form of a disk disposed in the plane perpendicularly to the direction of flow. That provides that the catalyst apparatus if of a very small construction.

r Preferably however the carrier body is in the form of a cylindrical or frustoconical or conical drum. That arrangement means that it is possible to treat particularly large amounts of gas.

As only a very slight pressure drop occurs in the catalyst apparatuses according to the invention when the gas flows through the carrier body, there is the possibility here of for example feeding fresh air to the exhaust gas flow in the case of exhaust gas catalytic converters for motor vehicles.

In that way, it is always possible to ensure that there is an excess of oxygen in the exhaust gas to be treated by the catalytic converter, without expensive regulation by the lambda probe. Thus the expensive lambda control system can be omitted and/or the engine can be operated with a better level of efficiency and/or a higher compression ratio.

It is then particularly preferred for the further medium (for example the fresh air) to be fed to the intake side of the catalytic converter by means of a driven device for conveying that medium.

It is further preferred, when using carrier bodies of a drumlike configuration, for the carrier bodies to be arranged in a chamber whose cross-section corresponds to a polyon, perpendicularly to the axis of rotation of the drum.

Preferably, in that arrangement, devices which oppose a rotary movement of the medium can additionally be provided in the interior of the chamber.

or Preferably an electric motor can be used as the drive device.

It is likewise possible for the drive device to be an exhaust gas drive, that is to say for example a turbine wheel which is driven by the exhaust gas flow. In that case the turbine wheel may also be mounted directly on the drum-like carrier ae body. It is also possible for the drive energy to be taken *s~t S from an engine whose exhaust gases are fed to the catalyst apparatus. For example the catalyst apparatus can simply be driven by a V-belt which is connected to the crankshaft of ,r the engine.

p It is particularly preferred if the carrier body comprises one or more fine grids or grills which are coated with the catalytic substance. A particularly light carrier body can be constructed in that way.

In that respect rolled (levelled) grids are to be particularyl preferred as they have a considerably lower frictional resistance in the medium by virtue of their substantially smoother surface.

The system according to the invention operates on the basis of the inertia and centrifugal force principle: Moving bodies seek to remain in motion, and moving bodies seek to move along a straight line.

The gas flow which moves through the exhaust gas pipe involves a flow speed of 88 m/sec in an example (engine rotates at 6000 revolutions per minute, swept capacity 5 1, exhaust gas pipe diameter 60 mm). In that situation the surface speed of the carrier body is between 25 m/sec to 100 o* 9 m/sec, depending on the respective speed of rotation. The gas reaction at the surface is multiplied by that artificially produced surface speed. Suitable measurements about the 0 increase in the reaction speed at the catalyst in dependence on the flow speed have already been conducted by the inventor. In those measurements, erroneous temperature measurement was effected on platinum thermobeads in the exhaust gas flow, which are produced by the catalytic reaction. The rise in temperature occurred as shown in the Table, in dependence on the speed of the exhaust gas flow: 9 4 Display coated Pt-thermo Differential temp Differential temp Differential at 2 1/min air at 4 1/min air temp at 6 1/ min air through-put through-put through-put

S

S.

S*

2t eq.

B 5* 4 a.

a

SB

4.

.4

C

4e 750 700 650 600 550 500 450 400 12.5 12.5 12.5 12.0 12.0 11.0 9.0 0.4 30.0 30.0 30.0 29.0 27.0 24.5 20.0 10.0 43.0 43.0 41.0 40.0 39.0 35.0 28.0 13.5 This Table is bsaed on a CO-proportion in the exhaust gas of With a higher CO-content in the exhaust gas, temperature increases of over 100 0 C were measured, although the thermobeads of a diameter of 1 to 1.5 mm were exposed to the gas flow at a temperature of 400 to-750°C. That showed that there was a temperature difference of more than 100 0

C

relative to the exhaust gas temperature, and thus thermal energy was liberated at the thermobead, which was produced by post-combustion of the CO- and CH-components present in the exhaust gas, at the thermobead. That effect makes it possible in accordance with the invention to convert the conventional honeycomb catalytic converters which are constructed on an oxide-ceramic basis for private motor car Otto-cycle engines to non-toxic metal catalytic converters.

Preferred embodiments of the invention are described in greater detail hereinafter with reference to the accompanying drawing in which: Figure 1 shows an embodiment of the invention in the form of an axial catalytic converter in a vertically sectional view, Figure 2 shows an embodiment of the invention in the form of a radial catalytic converter in a vertically sectional view, Figure 3 shows an embodiment of the invention in the form of an axial catalytic converter with additional auxiliary air feed through the stationary parts in a vertically sectional view, Figure 4 shows an embodiment of the invention in the form of an axial catalytic converter with additional auxiliary air feed through the movable parts in a vertically sectional view, ,00:0, Figure 5 shows a sectional view of a detail of an opening to *b V a the auxiliary gas outlet from Figure 4, eeoq .Figure 6 is a view from the front of a detail of an opening 9 to the auxiliary gas outlet from Figure 4, o0 Figure 7 shows a sectional view of a further especially preferred embodiment of the invention which is especially suitable for cleaning the exhaust gases of diesel engines, Figure 8 shows a detail of Figure 7, and 9 Figure 9 shows the embodiment according to Figure 7 from above.

Figure 1 shows an embodiment of the invention in which the medium to be treated flows substantially horizontally through a housing 10 in the form of a lying cylinder. A gas intake connection 12 for the medium to be treated' (for example exhaust gases from Diesel or Otto-cycle engines) is arranged at the left-hand end of the cylinder, in the upper region thereof. A gas outlet connection 14 for the treated medium is arranged at the right-hand end of the cylinder, in the upper region thereof. Preferably the two connections 12, 14 are not arranged coaxially but displaced relative to each other.

Disposed at the peripheral surface of the cylinder in the e 4 lower part thereof is an outlet connection 16 for the 4e** separation products (for example oil condensate). It will be appreciated that the connection 16 can be omitted if the 26. apparatus is used as a catalyst.

Mounted coaxially with respect to the axis of the cylinder 4. shape in the housing 10 is a shaft 18 which passes through the right-hand end face and which is connected to the compressed air or electric motor 20 which is disposed at that ~location. Four disks 22 are fixed on the shaft 18 at uniform spacings relative to each other, as movable parts. Between 9.

the disks 22, three stationary disks 24 are sealingly fixed to the housing 10 around same at uniform spacings relative to the movable disks 22. The shaft 18 passes through the stationary disks 24.

All the disks 22, 24 may comprise grid material or apertured material. Preferably the disks 22, 24 have respective mutually oppositely disposed regions 26 in the form of circular rings, with holes therein. The disks 22, 24 comprise the catalytically active material or are at least partially coated therewith.

Figure 2 shows a further embodiment of the invention in which the medium to be treated flows through a housing 110 in the form of an upright cylinder. A gas inlet connection 112 for the medium to be treated (for example exhaust gases from Diesel or Otto-cycle engines) is arranged at the right-hand peripheral surface of the cylinder in the upper region thereof. A gas outlet connection 114 for the treated medium is arranged in the centre of the lower end of the cylinder.

An outlet connection 116 for the separation products (for a ee example oil condensate) is disposed laterally in the lower

C..C

•e end of the cylinder. It will be appreciated that the Se O, connection 116 can be omitted if the apparatus is used as a catalyst apparatus. A shaft 118 is mounted in the housing 110 Ce..

C 6e e 4 coaxially with respect to the axis of the cylinder shape. The shaft 118 passes through the upper end face and is connected to the compressed air or electric motor 20 disposed at that S location. Fixed to the shaft 118 is a carrier disk 119 on which three hollow cylinders 122 which are of different S a, diameters and which are arranged concentrically at uniform spacings relative to each other are suspended, as movable Ce parts. Two stationary hollow cylinders 124 are fixed to a horizontal intermediate plate portion 125 of the housing 110 between the movable hollow cylinders 122, at uniform spacings relative to the movable hollow cylinders 122. Beside the stationary hollow cylinders 124 the intermediate plate 11 portion 125 has openings 127 which lead into a sump 130 disposed therebeneath, for the separation products.

The gas outlet connection 114 extends in the form of a pipe through the intermediate plate portion 125 to a position approximately at the mid-height level of the housing 110.

The upper end face of the housing 110 is in the form of a cover 132 which is fixed by means of a closure arrangement 134 and on which the motor 20 is fixed and the shaft 118 is mounted. In that way the apparatus can be easily taken apart, if that is necessary for maintenance or cleaning operations.

All the hollow cylinders 122, 124 can commprise grill material or apertured material. Preferably the hollow cylinders 122, 124 have respective mutually oppositely disposed cylindrical regions 126 with holes. The hollow 4 cylinders 122, 124 comprise the catalytically active material Sor are at least partially coated therewith.

re..

'2t? *490 Figure 3 shows a modified embodiment of the axial catalytic converter of Figure 1, in which an auxiliary gas can additionally be supplied.

e When employed as an exhaust gas catalytic converter fresh air can be supplied in order thus to improve the lambda value of the exhaust gas. In that case for example expensive lambda I8 regulation of the catalytic-converter Otto-cycle engine can be eliminated without disadvantages in terms of the exhaust gas emission values. In addition the feared overheating of the catalytic converter can be reliably prevented. It will be appreciated that when the apparatus is used as a chemical catalyst apparatus any auxiliary gas but also for example a reaction partner can be supplied.

In the embodiment shown in Figure 3 the stationary disks 224 are each duplicated and enclose a narrow hollow space or cavity 204. The cavity 204 is closed in an annular configuration in the region around the shaft 18. The peripheral surface of the housing 210 is also of a doublewall structure and encloses a further hollow space or cavity 202 with which the cavities 204 are in communication therearound. An auxiliary gas connection 200 communicates with the cavity 202. The auxiliary gas thus passes by way of the auxiliary gas connection 200 into the cavity 202 in the peripheral surface of the housing 210 and from there passes into the cavities 204 between the stationary disks 224. The auxiliary gas can cool the disks 224. Through apertured *t regions 226, in the form of circular rings, in the disks 224, the auxiliary gas then comes into contact with the medium which also has to flow through the apertured regions 226.

*296 Corresponding apertured regions 26 are also provided here in the movable disks 22. Alternatively the movable disks 22 can comprise grill material.

*0 0 A further embodiment of the axial catalytic converter of Figure 1 with an auxiliary gas feed is shown in Figure 4. In this case however in contrast to Figure 3 the auxiliary gas 0 is supplied not through the stationary parts of the apparatus but through the movable parts thereof.

0• In this embodiment the auxiliary gas connection 300 is disposed in the centre of the end face of the housing 310 opposite the motor 20. It is in the form of a stationary pipe which opens in the housing 310 in the interior of the shaft 318 which in this case is in the form of a tube. Sealing integrity as between the outside of the pipe of the auxiliary gas feed and the inside of the tubular shaft is afforded by way of a labyrinth seal 302. Four pairs each of two movable disks 322 are arranged on the shaft 318. Disposed between the disks 322 is a respective narrow hollow space or cavity 304 which communicates with the interior of the shaft 318 and which is closed at the outside edge of the disks 322. In this case also the stationary and movable disks 24, 322 have respective mutually oppositely disposed apertured regions 26 in the form of circular rings. The interior of the shaft 318 is sealingly closed off at the motor end.

In this case therefore the auxiliary gas is passed into the cavity in the shaft 318 through the auxiliary gas feed 300.

From there it is distributed to the cavities 304 between the ooo individual disks 322.. There it comes into contact through the ego[ apertured regions 26 with the medium which in fact also has to flow through the apertured regions. In that respect the configuration shown in Figure 4 enjoys the particular advantage that the auxiliary gas is conveyed outwardly by the centrifugal action in the rotating disks, without involving 0 0 S further auxiliary means for that purpose. That can even .000 compensate for a slightly increased pressure in respect of the medium to be purified, relative to the auxiliary gas.

eeeee2 In order further to improve that conveyor effect and at the S000" same time to prevent clogging of the outlet openings, the 36 outlet openings are preferably of the configuration shown in Figures 5 and 6. In that arrangement, disposed over the actual outlet opening is a curved cover 348 which is of a 14 closed configuration in the direction of rotation of the disk 322 and which rises in the opposite direction to the direction of rotation. The opening 350 through which the auxiliary gas issues is then disposed at the rear side of the cover 348. Preferably that construction can be produced by the curved covers 348 being produced by being pressed out of the previously flat disk, in which case the stamp or punch which is used for that purpose has a suitable break-away edge which produces the opening 350. Outlet openings of that kind, provided with covers 348, may be provided on all outward sides of the disks 322 of preferably only on the side of the disks 322 which faces away from the main direction of flow of the medium (large arrows in Figure 4).

In the embodiments of the present invention with rotating disks 322, instead of a disk 322 it is also possible to provide a fan wheel or impeller which then at the same time S..

provides for conveying the medium.

In these embodiments of the invention the "stationary" parts 05 can also be driven in a direction which is opposite to the direction of movement of the moving parts. That can produce an even better effect, but on the other hand the structural expenditure is greater.

0@*S This notion may be particularly easily carried into effect in the embodiment shown in Figure 2 as in that case it is only necessary for the previously stationary hollow cylinders also to be arranged on a rotating disk which is then driven for "0 example by a motor arranged at the bottom.

The embodiments of Figures 1, 3 and 4 must additionally be provided on the outside with an auxiliary shaft which extends parallel to the shaft 18 and which drives the disks that are to be moved in the opposite direction, for example by way of gear rings.

Figures 7, 8 and 9 show a further improved embodiment of the invention on the basis of the embodiment according to Figure 1. The medium to be cleaned is fed in through a gas entry connector 512 at the peripheral area of the cylindrical housing. Said gas entry connector 512 is leading at a driving device 500 for the shaft 518 on which the movable disks 522 are mounted. The driving device 500 here is consisting of a flat sheet which is perpendicularly mounted to the tangential direction of flow of the incoming gas and is extending through the rotational axis of the shaft 518 in a slot in S said shaft 518.

0* The arrangement of moved and stationary disks 522, 524 is corresponding to Figure i. On the gas exit side, said disks 522, 524 are followed by a further driving device 502 which is constructed as the driving device 500. Therefrom, the gas is leaving the apparatus via a gas exit connector 514 which, too, is provided as the peripheral area of the cylindrical housing in a tangential direction.

550059 By the construction of the driving devices 500, 502 according to the invention in operation a vacuum is created in the driving devices close to the shaft 518. This vacuum can be used for sucking an auxiliary gas, for example ambient air along the shaft 518. To this end, it is sufficient to dispense with a sealing of the shaft 518 with respect to the housing. The arrows 504, 506 are showing this stream of the auxiliary air.

To achieve an even better conveying of the medium to be cleaned, there is provided an impervious disk 508 between the driving device 500 on the gas entry side and the disks 522, 524 which is extending parallel to these disks and which is extending about to the half radius of the housing. Further between the disks 522, 524 and the driving device 502 on the gas exit side, there is provided a ring 510 which from the wall of the housing is extending inwardly to about the half radius.

According to the instant invention, the shaft 518 can be connected to a collectorless generator and an electric motor 550. Said motor can for example act as a driving motor during the cranking of an engine connected with the apparatus 0 according to the invention because in this instant the major *00* e. amount of soot is occurring while simultaneously no exhaust gas stream is created which would be sufficient to drive the ooe apparatus according to the invention. In the continuous operation then a part of the exhaust gas energy can be used for the production of current and possibly a generator can be dispensed with.

0SS*

S

0g 6, 0 .6Oe 0 6 6 The detail according to Figure 8 is showing a further preferred improvement of the invention: In the areas with little flow close to the peripheral area of the housing between the stationary disks 524, for example the filtered soot, is deposited. According to the invention, in this area between the stationary disks 524 there is provided an electric heating element 560 being mounted by means of a 17 ceramic insulation layer 562 on supporting rings 564. If during the operation in regular intervals electric current is sent through said heating element 560, the occurring soot then can be burned-off and has not to be removed with trouble.

In all embodiments according to the invention a further reaction partner in liquid form can be injected. For example when cleaning diesel exhaust gases additionally urea can be added to bind the nitrogen oxides.

S

Claims

2. Apparatus as claimed in claim 1, characterized in that the movable parts rotate in a cylindrical housing. 3 Apparatus as claimed in claim 2, characterized in that the axis of rotation of the movable parts is arranged coaxially 0090 with the cylindrical shape of the housing.
9. 4. Apparatus as claimed in one of the claims 1 to 3, characterized in that a drive device is disposed at one of 2" th end faces of the cylinder. S. Apparatus as claimed in one of the claims 1 to 4, characterized in that the movable parts are disk-shaped and that the stationary parts arranged therebetween are flat. 0 6. Apparatus as claimed in claim 5, characterized in that a gas intake connection is arranged at the one end of the 19 cylinder and a gas outlet connection is arranged at the opposite end of the cylinder. 7. Apparatus as claimed in claim 5 or claim 6, characterized in that the openings are arranged in respective mutually oppositely disposed regions, in the form of circular rings, of the movable parts and the stationary parts. 8. Apparatus as claimed in claim 5, claim 6 or claim 7, characterized in that the movable parts are arranged on a common shaft. 9. Apparatus as claimed in one of the claims 1 to 4, characterized in that the movable and stationary parts are in the shape of hollow cylinders and they are disposed alternately coaxially relative to each other. 1 0. Apparatus as claimed in claim 9, characterized in that a gas intake connection is arranged at the periphery of the cylinder and a gas outlet connection is arranged at the end.
11. Apparatus as claimed in claim 9 or claim characterized in that the openings are disposed in respective mutually oppositely arranged regions of the movable and stationary parts. 0000000 C
12. Apparatus as claimed in claim 9, claim 10 or claim 11, characterized in that the movable parts in the form of hollow C. cylinders are arranged on a common driven carrier disk.
13. Apparatus as claimed in one of the claims 1 to 12, characterized in that the stationary and/or the movable parts are in the form of apertured plates.
14. Apparatus as claimed in one of the claims 1 to 13, characterized in that the stationary and/or the movable parts are in the form of grills. Apparatus as claimed in one of the claims 1 to 14, characterized in that an electric motor is provided as the drive.
16. Apparatus as claimed in one of the claims 1 to characterized in that the stationary and/or movable parts of the arrangement are hollow and communicate with a feed device for an auxiliary gas.
17. Apparatus as claimed in claim 16, characterized in that the movable parts of the arrangement are hollow and have outlet openings for the auxiliary gas, which are formed by outward bulge portions which rise in the opposite direction to the direction of rotation and form a rearwardly directed opening.
18. Apparatus as claimed in claim 16 or claim 17, characterized in that the auxiliary gas is air. DATED this 27th day of November 1998 EDER MASCHINENFABRIK GMBH eO KG By Its Patent Attorneys DAVIES COLLISON CAVE