CA2046863A1 - Process for optimising fuel combustion with the minimum co emission and device for implementing it - Google Patents

Abstract

Description

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The present invention relates to a process for optimizing the combustion of fuels while ensuring minimal CO emissions, by the prior introduction of a liquid fog consisting of water, alcohol, and at least one extra additive into the air-fuel mixture and the generation of an homogenous liquid-fuel mixture. The present invention also relates to an apparatus for carrying out this process as defined in the preambles to claims 20 or 21.

The liquid fuels discussed herein and used are based on crude oil, in which connection Otto engines require fuels that are of a low boiling point and are not readily amenable to ignition, whereas diesel motors require fuels that are relatively amenable to ignition.

In an Otto engine, during formation of the mixture, "gaseous"
fuels are mostly mi-xed with air in a mixing chamber shortly before entering the cylinder; in the case of liquid fuels this is done in an atomizing devi¢e that is incorrectly referred to as a carburettor. In the case of fuel-injected Otto engines, liquid fuel is sprayed into the induction manifold close to the inlet valve, and less frequently directly into the cylinder. The fuel is vaporized at the time of ignition and, together with the air, forms the most homogenous possible mixture, at a mixture ratio that can only be changed within narrow limits, as a prerequisite for ignition and combustion. The combustion spreads, when the energy that is liberated is sufficient to cause neighbouring and :
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ignitable parts of the mixture to react, in which connection, during normal combustion, the flame front spreads without any abrupt changes in velocity so that it spreads away from the spark plug in an almost spherical form. The flame front velocity is made up of the combustion speed relative to the unburned mixture multiplied by the velocity with which the flame front is transported by the inherent motion of the gas mixture. It i8 known that the transportation velocity can be ~ffected by the induction process and the combustion chamber geometry used in the engine, in which connection a high degree of turbulence of the flow favours the mixing process, whereas a directed flow hinders the formation of an homogenous mixture. Factors that are known to disrupt combustion are so-called ignition knocking and surface ignition (premature or delayed ignition). In the case of ignition knock, part of the mixture that is as yet unaffected by the flame front ignites spontaneously and burns so violently that high pressure frequency waves result, and these cause the knocking and pinging that is heard, a~ well as thermàl and mechanical overloading of components such as pistons and bearings. In the case of surface ignition, heat is transferred to the mixture independently of the ignition time by hot points in the surface of the combustion chamber, e.g., such as caused by incandescent layers of carbon, the projecting edges of gaskets, or as a result of using spark plugs that are of too low a heat range.

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In diesel motors, the fuel is injected into the highly compressed hot air through a nozzle just before top dead centre (TDC~, whereupon the stream of fuel breaks up into individual droplets of various sizes and of different percussive force, and an heterogeneous mixture results. Self-ignition requires an appropriately high compression ratio, the lower limit of which decreases with piston diameter. Combustion starts with individual droplets of fuel, boiling and evaporation taking place as a result of thermal absorption from the surrounding hot air.
A mixing zone of a different concentration i8 formed about the still liquid $uel residue because of the suitable diffusion of fuel vapour and air that corresponds from 0 (droplet surface) to an infinitely increasing air ratio. The formation of soot is a familiar disadvantage in the case of diesel motors. In keeping with the boiling behaviour of the fuel, the molecules with a high proportion of water first burn, whereas the least volatile fractions are subjected in part to crack reactions when molecules that are difficult to ignite result from almost pure carbon and at low combustion temperatures these remain in the exhaust gas as unburned soot. This causes the very luminous yellow colour of a diffusion flame, in contrast to which premixed flames are blue (Otto motors).

Carbon monoxide, which results from inadequate combustion, forms a high proportion of injurious gas, particularly in the case of the exhaust gases generated by Otto motors. It is a known fact ~ ~ 2~6g6~

that carbon monoxide results mainly in the air depletion range as a result of incomplete combustion, the course of the reaction largely following water gas reaction. Because of the fact that the effective fuel-air mixture is not completely homogenous, carbon monoxide will also be formed even if there is an excess of air. For this reason, attempts to reduce the emission of in~urious substances by changing the shape of the combustion ohamber in order to enhance the ~wirling of the combustion have only ~ucceeded to a limited extent. The attempt to have the èngines run in a so-called lean mode requires controlled, high energy ignition and scavenging of the exhaust gases with the temperature of the combustion chamber walls as high as possible.

In part, however, the measures that were taken tend to reduce the efficiency of the engines. Some of them have had very little effect.

For this reason, the legislators have devoted a great deal o~
their interest in research to reducing exhau~t gas emissions by the use of catalysts. The catalyst requires a honeycomb surface with a platinum, radium, and paladium coating on which the final combustion of hydrocarbon compounds (HC) and carbon monoxide (CO) as well as the reduction of NOx in free nitrogen takes place. In the case of the so-called three-way catalyst, a closed regulating circuit for the supply of fuel is required (2 measurement as a regulating value by means of a so-called lambda probe). It is a - : . , , - -, - , . . ~, 2V~686~
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disadvantage, however, that catalysts do not permit the use of gasoline that contains lead, since this attacks the effectlve surface of the catalyst. Furthermore, catalysts require high combustion temperatures of 600 to 800-c. A not insignificant disadvantage is the increased consumption of fuel and the demand for motor designs that can be run with lead-free fuel of low oatane numbers. In the case of diesel engines, the catalyst described above is, for all practical purposes, ineffeative, because it does not burn the soot, or does so only to an insufficient extent. In addition, there is a great deal of concern with regard to the discharge of platinum into the environment.

It is known that so-called additives can be mixed directly into the fuel; however, the effect of these--if they have any efect at all--is mainly to increase lubrication within the engine.
With regard to reducing the emission of toxic substances, the additives that have been propo~ed up to now are for all practical pUrposes inefective.

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US-PS 3 767 172 proposes the addition of a mixture consisting of 2.5 parts water and 1 part methol alcohol to the fuel. When this ~; is done, it is intended that the alcohol have a cooling effect that will permit timing of the ignition point.

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20~686~ -It is the task of the present invention to describe a process and an apparatus of the type described in the introduction hereto in which combustion is optimized, that reduces the consumption of fuel, and considerably reduces the emission of toxic substances (in particular the emission of carbon monoxide).

Thl~ ta5k ha~ been solved by mean~ of the proces~ de~cribed in ¢laim 1.

The basic concept of the process, which is essential to the present invention, is to bring about complete combustion in that prior to being introduced into the combustion chamber the fuel is "atomized" such that during the combustion period, not only is there complete oxidation of the carbon-water particles in the area of the surface of the particles, but that there is also complete oxidation of all the carbon-hydrogen molecules in a droplet. In other word5, the surface that is available for combustion is increased by very fine breakdown of the fuel particles. To this end, a liquid fog is directed onto a fuel-air mixture, or a liquid fog base mixed with air, ls directed onto a flow of fuel such that it breaks down the drops of gasoline into very fine droplets. During this breakdown, positively or negatively charged droplets of gasoline are formed in large quantities and, under normal circumstances, these would reunite.
This recombination is prevented in that the neutral liquid , , ' . . .

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particles surround the droplets of gasoline in a mixture and thus cause them to remain finely divided.

Because of the more complete combustion, the fuel that is used iB
completely utilized with the result that when an Otto engine is operated, ~uel savings can reach 25%, and sometimes even 30%.
More complete combustion also reduces the emission of carbon monoxide, and in practical tests it was possible to measure carbon monoxide residues in the exhaust gas of less than 0.05%, which is considerably lower than the values achieved up to now using other technologies.

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The liquid or liquid mixture, respectively, displays at least one of the following properties:
- specifically heavier than the fuel, in order to be able to atomize it;
- a high anti-knock value in order that the liquid does not downgrade combustion within the combustion chamber;
i - the liquid should be able to increase the combustion time or reduce the combustion ~detonation) speed, so as to permit complete combustion of the hydrocarbons in each droplet of gasoline.

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In particular, the liquid fog either consists for the most part of distilled water, to which a weakly organic acid is added at a concentration between 1/500 to 1/200, and preferably 1/300 :

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relative to the distilled water, and alcohol, this liquid fog being added to the fuel at a ratio of 1:1000 to 15:1000 relative to the fuel. The water protects the alcohol against premature or explosive combustion. The weakly organic acid that is added has a cleaning effect. In addition, the mixture that has been described has a powerful neutralizing effect that preVents small particles of gasoline conglomerating to form larger particlee, and in addition, the mixture has good anti-knock properties which, in particular, makes it possible to use unleaded fuel in high-compression engines and also provides for a more event distribution of the ignition flame throughout the whole of the combu~tion chamber. Furthermore, the liquid is not chemically aggressive. Nevertheless, combustion without sharp peaks contains more energy, since all the particles are burned, and finally, the alcohol lowers the freezing point of the mixture to a con-~iderable extent and, li~e the organic acid, has good combustion characteristics. This also makes the good combustibility of the alcohol i5 also useful, for it also prevents the gasoline mixture becoming too lean, which is to be avoided, and this, in its turn, reduces the danger of insufficient combustion.

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It is preferred that the liquid contain 2 parts by volume of distilled water and 1 part by volume of alcohol, preferably a low-chain alcohol, in particular methanol and/or ethanol that, . . . .

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like water, burns more slowly than gasoline and prevents the formation of soot within the cylinder.

As an alternative to this, in order to solve this task, it i5 also possible to add a mixture of approximately equal parts of water and methanol with a small quantity of glycerine, on the one hand, and a methanol-oil mixture on the other, at a rate of 200 to 400 g, preferably 300 g, of oil to 5 1 of methanol. When this is done, the ratio of water to the fuel that is to be burned, like the ratio of the water-methanol mixture, should amount to approximately 2.5 1:2 1:200-300g.

For technical reasons, the water-methanol-glycerine mixture, on the one hand, and the methanol-oil mixture on the other hand, must be introduced into the fuel air flow separately, this being done in such a way that in a first stage a fog of water, methanol, and glycerine is added to the fuel-air mixture and the re3ulting mixture has the methanol-oil mixture added to it in a second stage. A synthetic oil that is resistant to high temperatures is used, and this will have a lubricating effect and will also help clean the combustion chamber. It is also preferred that the liquid have a low freezing point that, depending on the location where it is used, can be below -25-C, in order that the mixture can be used for winter operation without freezing.

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As a result of these measures, to a very large extent the deposition of incompletely burnt hydrocarbons within the combustion chamber and in the exhaust gases will be largely prevented. With reference to the depo6its in the combustion chamber, this also leads to a considerable reduction of friction during movement of the piston: the lubricating properties of the oil are retained for a longer period, since the oil is not contaminated by un~urned in~urious substances. As a secondary efect, there is the added advantage that the interval between oil changes can be considerably increased. In the case of Otto engines used up to the present, the discharge of unburned hydrocarbons and a build-up of these in the exhaust area also leads to the fact that they can prevent the discharge of gas.
Furthermore, water can very easily collect within such encrustations, and under normal conditions this can lead to premature rusting of the exhaust muffler. Thus, avoiding such deposits also increases the service life of mufflers and exhaust pipes by a considerable amount.

According to a further development of the present invention, the liquid to which the organic acid has been added consists to a large part of distilled water. Tests conducted with undistilled water have shown that the contaminants contained in such water have a harmful effect within the internal combustion engine and these effects can reduce the service life of the engine to a considerable extent, whereas pure (neutral) water furtheræ the ' .

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complete combustion of the hydrocarbons. In order to generate the liquid fog, the liquid is metered from a supply container and added to the atomizing chamber in which there is an almost constant level of liquid.

If one uses distilled water to which organic acid has been added and this is mixed with alcohol, it is preferred that the liquid be metered from a single supply container and introduced into the atomizing chamber, within which there i5 an almost constant level of liquid, a shaped porous body lying in the liquid through wh~ch air is drawn in from outside by the low pressure over the surface of the liquid: this air expresses the liquid within the porous body out of the remaining liquid in the form of very fine droplets (in the form of a fog), when the very fine droplets (the fog) is added to the fuel-air mixture or to the fuel through a regulating valve.

If, on the one hand, one uses a mixture of distilled water, methanol, and glycerine and, on the other hand, the oil-methanol mixture, this is me~ered into different supply containers into the particular atomizing chamber. When this is done, there is a porous body in the supply container that contains the water, and within the supply container that contains the oil-alcohol mixture, there is a plastic body that incorporates fine channels or outlet openings and is encased in a fine metal mesh. Air is drawn in from the outside by the low pressure above the level of .

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-- 204~863 liquid, from each body that serves as an atomizer; this air expresses the liquid that is located within the shaped body or the plastic body out of the remaining liquid in the form of very fine droplets (fog). Then the fog is added to the air-fuel mixture or to the flow of fuel in the different stages through an as~oclated regulating valve.

The ~almost complete) vacuum that exists above the surface of the liquid exerts a suction effect, which means that droplets of liquid that leave the moulded body or the plastic body, or their fine channels, respectively, are further and more finely divided because of friction. In the case of gasoline fuel-injected engines, the pressure effect that is exerted on the liquids can be enhanced in that the moulded body i9 additionally acted on by pressure through a pump that can be regulated. Then, the air that is drawn in carries the droplets of liquids into the partial vacuum area that exi~ts abov~ the surface of the liquid. When this happens, the droplets of liquid remain electrically neutral.

In order to prevent the injurious influences of polarization, which could be introduced by any charge carriers in the outside air, a further development of the present invention provides that the air that is induced is first discharged (neutralized). It is, of course, understood that the quantity of air that is induced must be considered during the addition of the remaining air to the fuel. In addition, and according to a further .. : ~- ~ . . .
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~046863 , }4 development of the present invention, humidity of the air from the external environment is considered in that a diaphragm reduces the delivery of air when atmospheric hunidity is high.
This reduction is important because otherwise too large a quantity of water would be introduced into the combustion chamber, where it would lead to the fuel mixture being too lean.

It is preferred that metering the liquid into the atomizing chamber (vaporizer chamber) be controlled electro-magnetically by means of a float. In the first instance, this float is intended to regulate the level of liquid in the atomizing chamber, i.e., to ensure an essentially constant level of fluid. In addition, as liquid is used, it ensures that the appropriate supply line is shut off and the system is changed over to the usual air induction operation, as is known from the prior art. Then, air is drawn in through the atomizing chamber without any addition and atomization of liquid.

In order to prevent liquid particles that are too large from getting into the air-gasoline mixture, provision is also made that the liquid fog be passed through a droplet separator that is arranged ahead of the chambPr outlet. Preferably, a fine-mesh, multi-layer strainer is used for this purpose although, as an alternative, it would be possible to use zig-zag shaped deflectors with baffle plates; these separate droplets that are too large by impact, or else reduce the size of such droplets.

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The droplets that are stopped then fall back into the liquid bath of the atomizer (vaporizer) chamber).

The very fine division of the fuel droplets is brought about in that the flow of liquid fog within a diffuser chamber i6 SO
directed onto the flow of fuel particle~ through radial inlets (jets) and through a central jet that the required shearing or reduction effect relative to the fuel particles take5 places. In the same way, a low pressure zone that is more or less annular is formed within the atomizer swirl chamber. This accelerates the liquid droplets-fuel-air mixture. In this instance, the addition of liquid is controlled, for example, by opening the carburettor valve. The velocity of the particles may amount to several metres per second. At the same time, the particles of liquid which are subsequently added to the fuel-air mixture prevent the small fuel droplets recombining to form larger droplets.

In addition, prior ~by time and space) to the atomization by the liquid that is added, the fuel can be pre-atomized, either directly or indirectly, by ultra-sound irradiation. However, this measure alone may not be sufficient even though the recombination of the fuel particles--according to the present invention--is prevented by neutral droplets of liquid, preferably of smaller diameter. Mainly, the liquid serves to suppress detonation and, on the other hand, it serves to maintain the combustion flame up to the point of complete combustion of the ~ ; ~ ' , ' ' -2~4686~

fuel particles. The engine runs quietly and regularly. Not least of all, the organic acid that i8 preferably added cleans the combustion chamber. The mixture of water-ethanol-organic acid is totally non-toxic to operating personnel and is not explosive at normal pressure and normal temperature.

What has been said above, about the fog mixture consisting of dlstillèd water, an organic acid, and alcohol, applies to the case that distilled water-methanol-glycerine mixture, on the one hand, and the methanol-oil mixture, on the other hand, is used in separate atomizing chambers.

During the combustion of the fuel, the glycerine is heated to the particular combustion temperature without any chemical reaction and serves as a heat reservoir in the flow of exhaust gas that leaves the combustion chamber. If one in~tall~ a net-li~e diffuser in the exhaust pipe or exhaust header for a series of combustion chambers, the particles that have only been partly burned can themselves ignite, optionally after being atomized on the diffuser, because of the temperature that is between 800 and lOOO-C in the diffuser area, where they finally burn in a flame that forms there. This secondary combustion also brings about an additLonal reduction of carbon monoxide and entails the advantage that, compared to a catalyst, it proceeds for all practical purposes without any loss of performance.

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It is a known fact that during conventional operation of an internal combustion engine, combustion will depend to a very great extent on engine temperature or engine speed. Combustion in engines known from the prior art, particularly when idling, i8 particularly bad, and the CO content is particularly high. For this reason, when the motor is idling, it is driven only with the liquids that have been described, when the supply of gasoline through the engine idling by-pass line is throttled back to practically zexo.

However, it is preferred that the liquid that contains the organic acid is added at a proportion of lo:1000 to 15:1000 relative to the quantity of fuel. This means that for a quantity of fuel amounting to loOO 1, on average, only about 1 to 1.5 1 of additional liquid will be required, so that the fluid supply tank that is required takes up only a little space and requlres no costly enlargement of the engine compartment. The same thing applies to the use of a mixture of water-methanol-glycerine and the methanol-oil mixture.
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In addition, it is preferred that when the speed of the engine is accelerated (during kick-down) the air that is drawn in passes in .
pulses into the atomizing chamber through a one-way valve that opens and closes at high frequency. The opening and closing - frequency of the valve is in the trans-sonic range, which results .~, :`
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in improved atomization of the liquid in question within the combustion chamber.

In addition, the process according to the present invention also proposes that any residual substances that leave the combustion chamber when incompletely burned is subsequently burnt in an exhaust pipe as a result of self-ignition in a net-like diffuser, whereupon the glycerine serves as a heat reservoir according to the temperatures within the combustion chamber.

The task imposed on the apparatus according to the present invention has been solved by the features set out in patent claim 20 or patent claim 21. Further developments of the apparatus according to the present invention are described in the sub-claims 22 to 42.

Essential components of the apparatus are one or two supply tanks for the liquid or liquids, the vaporizers or atomizers for the liquid that are supplied from these containers, and an atomizer swirl chamber with the radial feed lines described heretofore and the central feed line for the liquid fog and, optionally, a neutralization apparatus for the air that is induced. As discussed above, depending on the conditions under which the engine is operating, the liquid fog--with or without air--is mixed with the fuel, mostly in one or two pre-mixing chambers.

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The descriptions which follow relate initially only to an atomizer in which the distilled water and alcohol to which an organic acid has been added are atomized.

In addition to the regulating devices for the addition of liquid, such as are normally required, the atomizer or vaporizer for the liquid also incorporates a pre-chamber with a float that is connected to the ~upply container, this float being connected to a solenoid valve that controls the flow of liquid. The actual vaporizer or atomizing chamber incorporates a low-pressure controller that simultaneously serves as the outlet or connecting element to the above-discussed atomizer swirl chamber. A porous moulded body serves as the "atomizer" for the liquid, it being preferred that this be an air and liquid permeable compressed compound body that is submerged in the liquid within the atomizing chamber and which is connected or is connectable to the outside environment through a line. This line incorporates an additional regulator for the air supply. In other words, the moulded body incorporates an air induction chamber that is connected to ambient pressure or else is connected to a pump (in the case of fuel-injected engines~ through which an air supply is possible either directly or indirectly. When the motor is running, the partial vacuum in the atomizer (vaporizer) chamber is maintained. It is preferred that the particles of liquid are not only carried along by the air that is drawn into the moulded body but that they are also further divided by friction as a '~

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result of the thin channels within the moulded body, when they move through the outlet into the atomizer swirl chamber where they impact on the flow of fuel particles. The larger partlcles of liquid are held back by a droplet separator and fall back into the bath of the atomizing chamber. The partial-vacuum controller not only maintains the vacuum pressure in the atomizing chamber, but simultaneously regulates the addition of liquid to the fuel.
A shut-off valve between the supply container and the pre-chamber that preferably supplies liquid into the pre-chamber by increments, a central switch that interrupts both the removal of liquid from the supply tank and the supply of oxygen to the atomizing chamber when the motor is switched off, and also controls the pump discussed heretofore if the liquid is used up and the internal combustion engine is switched over to a mode of operation as in the prior art also serve as additional control devices. In addition, the central switch also controls the neutralizer for the ambient air that is drawn in. It is , ~
preferred that the feed line to the atomizer swirl chamber also incorporates an electronic distributor that regulates the central jet inlet and the radial jets or their feed. In particular, the electronic distributor also prevents the particles of liquid combining to form larger drops before they are injected into the atomizer swirl chamber. The interior space within the atomizer swirl chamber is so configured that it is suitable for building up a turbulent flow field. When this taXes place, the fuel droplets are distributed, on the one hand, by a bombardment of - ..

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particles (droplets) of smaller diameter from the outside to the inside as well as from the inside to the outside, mixed with the droplets to form a largely homogenous mixture, and gradually, because of the suction effect, are drawn off in the direction of the engine cylinder. The atomizer swirl chamber can thus be very ~hort, e.g., can be as thick as a carburettor seal, in place of which the atomizer ewirl chamber can preferably be inserted.

In a further configuration of the present invention, above the atomizer swirl chamber, preferably at a distance of 1.5 to 2 mm, there is an ultra-sound system that serves to further reduce the gasoline and liquid particles that have already been hiqhly swirled.

If, in place of this, one uses substances that do not dissolve in each other, such as a mixture of methanol, distilled water and glycerine, on the one hand, and a methanol-oil mixture on the other, then two atomizing chambers and two atomizer ewirl chambers will be required. In this connection, this results in the special feature that no porous shaped body will be required for its atomization/vaporization: a plastic body that incorporates very fine outlet channels, which is some 50 mm long, and which is encased in a metal mesh or net is incorporated in order that the methanol-oil mixture is sufficiently atomized.
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For the event that glycerine is used, according to a further development of the present invention, an exhaust system that incorporates a net-like diffusor of corrosion-resistant material is lncorporated after the combustion chamber or combustion chambers; auto-induced secondary combustion takes place in this a~ a result of the hot exhaust gases. The mesh size of the diffusor lies somewhere in the range of 0.5 to 3 ~m, preferably 1 to 2 ~m, which ensures that the unburned or partially burned particles of fuel that still have a high C0 content are broken up on the mesh so that the combustion surface is enlarged. In this case, the glycerine acts as a thermal carrier, i.e., in the area in which the diffusor is arranged, the temperature of the exhaust gases lies between 800 and lOOO-C, as was formerly the case, which results in this secondary combustion. The secondary combustion is improved if the mesh size of the net-like diffusor is smaller at the exhaust gas outlet end than in those areas that precede it. Preferably, the flow channel for the exhaust gases that is free and not covered by the diffusor net is configured so as to be concave which means that the opposite convex area of the diffusor net touch each other in the middle section. In addition, according to a further development, paddle-like deflector plates can be provided in the diffusor net, these extending in a longitudinal direction, and which allow the exhaust gas to pass through in a laminar flow. In order to prevent high temperature stresses on the actual exhaust pipe, the exhaust pipe can be provided with an interior fire-resistant covering in the area of ^~ 2~6~6~

the diffusor. The diffusor works on the principle of a gas lamp within the flow of which a net-like fabric is arranged, and which ensures complete combustion without the disadvantage of a high level oS mechanical resistance.

Embodiments of the present invention are described in greater detail below on the basis of the drawings appended hereto. These drawings show the following:

Figure 1: a perspective view of the apparatus according to the present invention for retro-fitting to a gasoline engine:
Figure 2: a diagrammatic cross sectional view of the apparatus according to the present invention;
Figures 3 and 4: as in ~igures 1 and 2 but in each instance with double supply, atomizer, and atomizer swirl chambers;
Figure 5a, b: a cross section from the exhaust pipe system with a diffusor in longitudinal section;
Figures 6a to c: cross sectional views as in figure 5a and 5b;
Figure 7: a cross section through an atomizer plastic body.

In order to retrofit this system to a conventional gasoline engine, one requires a supply container 1 that is connected through a flexible hose 22 to the atomizer 18. A connecting line ~68~

23 runs from this atomizer 18 to the atomizer swirl chamber 13 that is installed in place of the usual carberettor gasket. The atomizer swirl chamber consists of a gas and liquid permeable material that cannot be charged electrostatically, which is to say, which remains neutral.

The air that i5 required to operate the apparatus according to the present invention is drawn in through the air induction connector 24 that incorporates a diaphragm that closes appropriately at high levels of ambient air humidity and draws in less air. In detail, the housing 18 that is shown in figure 2 incorporates the antechamber 2 that is fitted with a float 3 that serves to regulate the level of liquid in the atomizing chamber 4 that is connected to the antechamber 2. Thls aonnection can be broken by the float if necessary, for example, if the neutral liquid has been consumed. Within the atomizing chamber 4 there is a shaped porous body 5 that is connected on one side to a line 19 through a regulator 11 to the atmosphere, and on the other side is connected through a line ~ to the pump 6 that is controlled by another regulator 12. In addition, the atomizing chamber 4 has a droplet separator 7 between the porous body 5 and the low pressure ~partial vacuum) regulator that also serves as the outlet valve of the atomizing chamber 4; this separator 7 only permits the pa~sage of drops of liquid that are less than a specified diameter. In addition, between the supply tank 1 and the antechamber 2 there is a controllable shut-off ' 2~68~3 valve 10. Air can be drawn in either in an antechamber or through a corresponding induction line 20 or the connector 24 described above in connection with figure 1. A neutralizer is incorporated in this antechamber or the line 20 and thi prevents charge carriers entering the atomizing chamber 4. The atomizing ¢hamber 4 i5 connected to the atomizer swirl chamber 13 by way of the previously-described low pressure regulator 9 and the hose 23. This swirl chamber 13 incorporates an electronically controlled distributor 14 which feeds fog-like liquid to both the central jet 15 and the radially arranged jets 16 in such a way :
that the liquid is directed onto a flow of fuel or fuel air mixture and breaks this down into finer droplets than was formerly-possible and then keeps the size of these droplets constant.

The apparatus accordlng to the present invention wor~s as follows:

The liquid, composed of 2 parts distilled water, 1 part ethanol, and 1:300 organic acid relative to the water, preferably an organic acid that has a cleaning effect on the interior of the engine, is drawn from the supply container 1 through the line 22 in pulses by means of the controllable shut-off valve 10 into the antechamber 2, from where it is passed to the atomizing chamber 4 where it is soaked up by the porous-shaped body. Within the atomizing chamber 4 there is a pronounced partial vacuum above ' : ' .:
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2a~6g~3 the porous-shaped body or above the level of the liquid, and this results in "vaporization" of the liquid. Because of the fact that the outside pressure is at least 15 times greater than the partlal vacuum in the atomizing chamber 4, air passes into the shaped body along the line 19, and as it pas6es through the fine channels made in the shaped body 5 it carries the liquid along with it. Because of the high flow rate, the liquid is broken up into flne droplets because of friction, and bubbles that reach the surface of the liquid are exposed to a very great shear effect that bursts them so that they form many small bubbles.
This leads to the formation of a fog made up of extremely fine droplets of liquid. Any larger droplets of liquid that remain are caught by the droplet separator 7 and fall back into the liquid bath or to the bottom of the atomizing chamber 4. The liguid fog is passed to the electronically controlled distributor 14 ~rom the low pre9sure regulator along the line 23 from where it is metered to ~ets 16 that are arranged in a ring and to a central jet 15. These jets are arranged in an atomizer swirl chamber 13 (approximately 2 to 5 cm long) through which the fuel or fuel-air mixture flows. If the liquid droplets meet the flow of fuel at high speed, then they break up the droplets of fuel into very fine droplets of small diameter. The droplets are prevented from recombining because the liquid that is located as a "buffer" between any electrically charged droplets of gasoline, is neutral. The mixture that passes out of the atomizer swirl chamber 13 can then be burned in a combustion chamber, e.g., : . ' '' , . , , ~ ~` 2~g~

within the cylinder of an Otto engine, when the liquid supports combustion such that it is maintained until complete oxidization of the hydro carbons within the gasoline have been complete oxidized and, at the same time, it prevents any detonation.
Complete Gombustion is coupled with minimal emission of carbon I monox~de, which lies well below 0.5% even in the case of large capacity engines.

The measures set out according to the present invention also prevents the build-up of carbon within the combustion chamber, which, combined with moisture, becomes highly corrosive. In addition, carbon deposits on piston rings are avoided; as a rule, up to now these have led to a reduction of compression and to rapid wear of the cylinder. The same thing applies to valve surfaces, spark plugs, and to the whole exhaust system.

A further important secondary effect of the process according to the present invention is the avoidance of so-called knocking.
The liquid that is used ensures even distribution of heat within the combustion chamber and prevents the build-up of abrupt combustion (detonation~.

In tests that have been conducted up to now, it was possible to achieve gasoline economies of up to 35% as well as reduced carbon monoxide values which in part even lay below 0.05%.

:

:

:

204~8~

In contrast to the illustration shown in figure l, the apparatus shown in figure 3 incorporates a supply container l that is made up of two chambers with feed lines 22, through which the liquid ed to the antechambers 2 and 2' by means of a controllable shut-off valve 10 or 10'. The construction of the atomizing chambers 4 and 4' (see figure 4) is the same except that in place of the porous-shaped body 5, a porous-shaped body (5') is provided, this being enclosed with a metal mesh; this is shown in greater detail in figure 7. This body (5') consists of a porous, essentially cylindrical plastic block (32) that is approximately 40 mm in diameter and approximately 50 to 60 mm long and incorporates a central blind drilling (33) of a diameter of between 2 and 3 mm, into which the air inlet channel (line 19) opens out. The plastic block i8 enclosed in a tightly applied wire mesh (metal mesh) with a mesh slze o~ approximately 0.2 ~m and incorporate~ annular or spiral grooves (34) that are at most 2 mm wide on its outer covering; these are arranged at an axial interval of 5 mm. This groove or these grooves ~34) serve to collect any bubbles that are formed. This takes into consideration the fact that the methanol vaporizes more easily than water and the oil may not permeate the particular body 5, or it is not intended to enter into a chemical reaction with a shaped body 5 that is composed of minerals. In addition, the atomizing chambers 4 and 4' are connected to each other by way of a line that incorporates a regulating flap valve 24 lnot shown in ' , 2~46~6~

the illustration and may be wrongly numbered in figure 3--Tr.]
that is operated by an electronic control 25 or a solenoid valve.

Whereas the first chamber of the supply tank is filled with distilled water, the second chamber of the supply container 1 contains a methanol-oil mixture. The fog-like liquid vapour passes from the two atomizing chambers 4 or 4', respectively, into one of two atomizer swirl chambers 13, 13' that are arranged adjacent to each other, so that first of all a water mist is added to the air fuel mixture and then a methanol-oil vapour is added to`the mixture that results from this. Becausa of the ~act that the particular system components such as feed and drain lines c~rrespond to each other, reference can be made to the previous embodiments with regard to the atomizing chambers and the atomizer swirl chambers.

In addition, the feed lines 19 and 19' incorporate a one-way lip valve 36 or 36' that is made to oscillate in the event that additional air is supplied through the line 39 and this then passes the air in pulses to the porous-shaped body 5 or the plastic body ~'. This additional quantity of air is supplied as soon as the shut-off valve 38, which should be open when the gas pedal of a passenger vehicle is kicked down, is opened by the regulator 37. When the engine is idling or not under load (when coasting down hill) the valve 38 remains closed. At the same time, when idling or when unloaded, such as when a passenger :

20~6~6~

vehicle is coasting down hill, the gasoline supply is cut back to almost O by way of a throttle valve; in addition, the needle valve in the bypass ~the idling ~et) is closed. In this case, only mixture that comes from the atomizing chambers 4, 4' is burned. When this ls done, the glycerine, in particular, will work to reduce the generation of Nox.

Figure 5a shows a longitudinal cross section through an exhaust pipe 26 in the area that is immediately adjacent to the combustion chamber. The flow of exhaust gas that is indicated by the four arrows 27 is passed in total to this exhaust pipe 26, which incorporates a diffusor 28 that extends over the whole cross section of the pipe in the direction of the exhaust gas.
As can be seen from the cross section drawing in figure 5a, the di~fusor is of a net-like construction, the space that is not covered by the diffusor first tapering conically to zero and then expanding conically in a corresponding manner. The incoming flow of exhaust gas, which contains glycerine that has been heated to combustion temperature and which carries the unbu~ned or partially burned particles, is passed through the diffusor net where, because of the small mesh size, which grows denser in the direction of the flow of exhaust gas, further atomizes the unburned or partially burned particles. The high temperatures that exist in this area lead to self-ignition of the unburned particles, when a flame 30 is formed. This extends across the whole diffusor and to an almost equal length. The diffusor .. - ~, .. .
:-:
,, ' 2~468~

should be approximately 25 cm long so that a total flame lengthof approximately 50 cm results. The exhaust pipe 26 is protected by means of an internal flame-resistant coating 29.

The taper of the flow space that is not covered by the diffusor net can be seen in figure 6a to figure 6c, the reference number ~ 28 referring to the edge of the diffusor net.

:~ .
Figure 5b shows an embodiment in which a two-stage diffusor is used. The first stage corresponds to that shown in figure 5a, so that no explanation of this is necessary. However, this diffusor is followed by a second section 28' that is correspondingly constructed, the diffusor mesh size growing smaller towards the exhaust outlet. The first diffusor section 28 should be approximately 15 cm long, and the second section 28' should be approximately 10 cm long.

In addition, it can be seen from figure 6 that several baffle plates that extend in the longitudinal direction are incorporated and these are used to guide the exhaust flow in a manner that is as laminar as possible through the area in which the diffusor is arranged.

:, In the apparatus that is shown in figures 3 to 6, it is preferred that glycerine be added as a function of the quantity of fuel , - ' -~ 2a~68~

that is used. In particular, the amount of glycerine that is added is maximal in the case of a so-called "kick-down."

The service life of the diSfusor ~hown in figures 5 and 6 will not, as a rule, be less than two years, particularly if the net ie of stainless steel that can withstand temperatures of up to approximately 1800-C.

., , ~ ' - :,: -` "~ . : '

Claims (42)

PATENT CLAIMS

1. A process for optimizing the combustion of fuels with the minimal emission of carbon monoxide by the prior introduction of a liquid fog containing water, alcohol, and at least one additional additive into the air-fuel mixture and generation of an homogenous liquid-fuel-air mixture, characterized in that the (de-ionized) neutral liquid fog consists for the most part of distilled water to which a weakly organic acid at a concentration of between 1/500 to 1/200, preferably 1/300, relative to the distilled water, and alcohol, and is added to the fuel at a ratio of 1:1000 to 15:1000, preferably 10:1000 to 15:1000, relative to the fuel, the liquid fog in the form of very fine droplets being mixed with the fuel-air mixture in a turbulent mixing field;
or in that the (de-ionized) neutral liquid fog consists of equal parts, on the one hand, of approximately equal quantities of water and methanol with 200 to 300 g of glycerine and 4.5 1 of water/methanol, and, on the other hand, of a methanol-oil mixture in a proportion of 200 to 400 g, preferably 300 g, of oil in 5 1 of methanol, and added to the fuel at a ratio of 1:1000 to 15:1000, preferably 10:1000 to 15:1000 relative to the fuel, the liquid fog in the form of very fine droplets being mixed with a fuel-air mixture in a turbulent mixing field.

2. A process as defined in claim 1, characterized in that the liquid or an appropriate liquid mixture has a freezing point below -25°C.

3. A process as defined in one of the claims 1 or 2, characterized in that the liquid to which the organic acid is added for every 2 parts by volume of distilled water contains 1 part by volume of alcohol, preferably low-chain alcohols, or the liquid to which the glycerine has been added, contains a mixture of 2.5 parts by volume water, 2 parts of methanol, and 200 to 300 g of glycerine.

4. A process as defined in one of the claims 1 to 3, characterized in that methanol and/or ethanol is used.

5. A process as defined in one of the claims 1 to 4, characterized in that the weakly organic acid is of the group of carboxylic acids.

6. A process as defined in one of the claims 1, 2, or 4, characterized in that the oil is a synthetic oil with a high vaporization temperature.

7. A process as defined in one of the claims 1 to 6, characterized in that the liquid is atomized in a chamber with a pressure that is 20 to 30% below atmospheric pressure before it is added to the air-fuel mixture.

8. A process as defined in claim 7, characterized in that liquid that consists of alcohol to which an organic acid has been added and alcohol is metered from a supply container into an atomizing chamber in which there is an almost constant level of liquid, a porous-shaped body lying in the liquid, air being drawn in from outside through the low pressure above the surface of the liquid, this air expressing the liquid within the shaped body from the remaining liquid in the form of very fine droplets (fog), these very fine droplets (the fog) then passing through a regulating valve and being mixed with the air-fuel mixture or the fuel.

9. A process as defined in one of the claims 1 to 6, characterized in that the mixture of distilled water, methanol, and glycerine, on the one hand, and the oil-methanol mixture on the other, is metered into different supply containers into the atomizing chambers, there being a porous-shaped body (pisolite) in the supply container with the water, methanol, and glycerine, and a porous plastic body encased in a metal mesh being in the supply container with the alcohol-oil mixture, through which air is drawn in from outside through the low pressure above the level of liquid, this air then expressing the liquid located within the shaped body or the plastic body out of the remaining liquid in the form of very fine droplets (fog), these very fine droplets (fog) passing through a regulating valve and being added to the air-fuel mixture or to the fuel.

10. A process as defined in claim 8 or claim 9, characterized in that the air that is drawn in has been previously discharged (neutralized).

11. A process as defined in one of the claims 8 to 10, characterized in that the supply of air is regulated, preferably by means of a diaphragm, such that the supply of air is reduced when atmospheric air humidity is high.

12. A process as defined in one of the claims 1 to 11, characterized in that the metering of the liquid into the particular atomizing chamber is controlled electro-magnetically by means of a float.

13. A process as defined in one of the claims 9 to 12, characterized in that the shaped body or the plastic body is additionally subjected to pressure through a controllable pump, this corresponding to the pressure with which the fuel is injected through an injector jet.

14. A process as defined in one of the claims 1 to 7 and 9 to 13, characterized in that when the speed of the engine is increased the air that is drawn in is fed to the atomizing chamber in pulses as a result of the high-frequency (ultra-sonic) range opening and closing of a one-way valve.

15. A process as defined in one of the claims 7 to 14, characterized in that the fog-like liquid is passed through a droplet separator, preferably a fine-mesh sieve, which only passes droplets that are below a certain diameter that is governed by the size of the mesh, preferably of less than 0.3 mm, before it is added to the air-fuel mixture during the generation of a turbulent flow field.

16. A process as defined in one of the claims 1 to 15, characterized in that the liquid fog is injected through a central and through radial inlets (jets) into a diffusion space during the generation of a turbulent flow field such that the fog droplets that strike the fuel particles break up the fuel particles (mechanically) and mix with the reduced fuel particles such that any recombination of the fuel particles to form droplets of larger diameter is prevented.

17. A process as defined in one of the claims 1 to 16, characterized in that the fuel either before or during the injection of the liquid fog is atomized by ultra-sound, preferably by irradiating the carberettor valve that serves as an impact baffle for the fuel particles is irradiated with ultra-sound.

18. A process as defined in one of the claims 1, 2, 4, 6, 7, or 9 to 17, characterized in that in a first stage a liquid fog consisting of distilled water, methanol, and glycerine and, in a second stage, the liquid fog consisting of an alcohol-oil mixture is blown into the fuel or fuel-air mixture.

19. A process as defined in one of the claims 1, 2, 4, 6, 7, or 9 to 18, characterized in that the incompletely burned fuel particles leaving the combustion chamber undergo secondary combustion in an exhaust pipe as the result of self-ignition in a net-like diffusor, the glycerine serving as a heat accumulator corresponding to the temperature within the combustion chamber.

20. An apparatus for carrying out the process according to one of the claims 1 to 19, with an atomizer (18) that is incorporated ahead of the carberettor or an antechamber of the engine, for a liquid, which is connected essentially to at least one supply container (1) for the liquid, an antechamber (2) with a float (3), that is connected to a solenoid valve that controls the flow of liquid fog, and which has at least one atomizing chamber (4) that is connected to at least one atomizer swirl chamber (13) to mix the liquid fog with an air-fuel mixture or the fuel, the atomizing swirl chamber (13) incorporating a feed (jet 16) for the liquid fog that is so oriented that it meets the air-fuel mixture or the flow of fuel perpendicularly, characterized in that the atomizing chamber (4) incorporates a low-pressure regulator (9); in that a porous-shaped body (5), preferably a compressed compound body that is air and liquid permeable, with a porosity of up to 60%, is completely immersed in the liquid within the atomizing chamber (4) and which is or which can be connected through a line (19) that incorporates a regulator (11) to the outside environment (air); and in that an ultra-sound source is incorporated ahead of the atomizer swirl chamber in the fuel feed line.

21. An apparatus for carrying out the process as defined in one of the claims 1 to 19, with an atomizer (18, 18') for a liquid that is incorporated ahead of the carberettor or a pre-mixing chamber for the engine, which has essentially at least one supply container (1) for the liquid, an antechamber (2, 2') with a float (3, 3') that is connected to a solenoid valve that controls the flow of liquid fog, and at least one atomizing chamber (4, 4') that is connected to at least one atomizer swirl chamber (13, 13') that mixes the liquid fog with the air-fuel mixture or the fuel, the atomizer swirl chamber (13, 13') incorporating a feed (jet 16, 16') for the liquid fog, this being so oriented that it is largely perpendicular to the air-fuel mixture or the flow of fuel, characterized in that two supply containers or one supply container (1) with two chambers, two atomizing chambers (4, 4') that each have a low pressure regulator (9, 9') and two atomizer swirl chambers (13, 13'), a porous-shaped body (5), preferably a compressed compound body with a porosity of up to 60%, which is preferably permeable to air and liquid, is completely immersed in the liquid within the first atomizing chamber (4) and is connected through a line (19) that incorporates a regulator (11) with the outside environment (air), or can be connected thereto, there being a plastic body (32) that is enclosed in a corrosion-resistant metal mesh (35) within the second atomizing chamber (4'), this also being connected or connectable through a line (19') that incorporates a regulator (11') to the outside environment (air); and in that an ultra-sound source is incorporated in the fuel feed line ahead of each atomizer swirl chamber (13, 13').

22. An apparatus as defined in claim 20 or claim 21, characterized in that the feeds (jets 16, 16'; 15, 15') are connected to the atomizer (18, 18') through a pressure regulator (9, 9') and an electronically controlled distributor (14, 14').

23. An apparatus as defined in claim 20 to claim 22, characterized in that between the supply container (1) and the antechamber (2, 2') there is a controllable shut-off valve (10, 10') that preferably passes liquid into the antechamber (2, 2') incrementally, in pulses.

24. An apparatus as defined in one of the claims 20 to 23, characterized in that the float (3, 3') shuts off the feed between the antechamber (1) and the atomizing chamber (4, 4') if no more liquid can be supplied from the supply container (1) or if the level of liquid in the antechamber (2,2') falls below a pre-selectable level.

25. An apparatus as defined in one of the claims 20 to 24, characterized in that the air feed lines (19, 19') each incorporate a one-way lip valve (36).

26. An apparatus as defined in claim 25, characterized in that in the immediate vicinity of the valves (36, 36') an additional air induction line (39) that is provided with a shut-off valve (38) that can be operated by a regulator (37) opens out into the lines (19, 19'), by means of which air that is drawn in through the line (39) causes the valves (36, 36') to oscillate at a high frequency in the ultra-sound range.

27. An apparatus as defined in one of the claims 24 to 26, characterized in that an additional air induction line (8, 8') that is connected to a controllable pump (6, 6') opens out into the shaped body (5) and/or into the plastic body (5').

28. An apparatus as defined in one of the claims 20 to 27, characterized in that there is a droplet separator (7, 7'); preferably a mechanical multi-layer mesh sieve (7, 7') ahead of the atomizer outlet or the pressure regulator (9, 9'), this being intended for such droplets that exceed a (specific) size of at most 0.3 mm.

29. An apparatus as defined in one of the claims 20 to 28, characterized in that there is a neutralizer (17), preferably a condenser, incorporated in the air induction channel (19, 19') or an antechamber (20, 20') of the atomizer (4, 4').

30. An apparatus as defined in one of the claims 20 to 29, characterized in that all of the regulators or valves and the distributor (3, 9, 10, 11, 12, 14, 24, 25, and 36 to 38) are connected to each other through a central control system.

31. An apparatus as defined in one of the claims 20 to 30, characterized in that an indicator is provided to show the level of liquid in the supply container (1) or the supply containers or chambers, or to indicate that the liquid has been exhausted.

32. An apparatus as defined in one of the claims 20 to 31, characterized in that the atomizer swirl chamber is built in two stages, each stage being connected to a supply container (1).

33. An apparatus as defined in one of the claims 20 to 32, characterized in that the ultra-sound source is oriented towards the carberettor valve that serves as an impact baffle for the fuel.

34. An apparatus as defined in claim 33, characterized in that the ultra-sound source is arranged directly above the atomizer swirl chamber, preferably at a distance of 1.5 mm to 2 mm.

35. An apparatus as defined in one of the claims 20 to 34, characterized in that two atomizer swirl chambers (13, 13') are provided, through which, in the first stage (13), a fog consisting of a water-methanol-glycerine mixture and in the second stage (13'), a methanol-oil mixture is blown into the fuel or the fuel-air mixture; and in that an outlet pipe (exhaust) is arranged after the combustion chamber(s), through which the exhaust gases (27) flow, this incorporating a net-like diffusor (28) that is of corrosion-resistant material, in particular stainless steel, that covers the whole of the cross section of the pipe, within which secondary combustion initiated by the hot exhaust gases (27) takes place automatically.

36. An apparatus as defined in claim 35, characterized in that the mesh size of the net-like diffusor (28) is between 0.5 and 3 µm, and grows smaller towards the outlet end of the exhaust system than it is in the previous section.

37. An apparatus as defined in claim 36, characterized in that the mesh size towards the exhaust gas outlet end is half as large as it is in the first section.

38. An apparatus as defined in one of the claims 35 to 37, characterized in that the free through-flow channel for the exhaust gas (27) that is not covered by the diffusor net (28) is concave, the two opposite convex areas of the diffusor net touching each other at about the mid-point.

39. An apparatus as defined in one of the claims 35 to 38, characterized in that the free through-flow channel for the exhaust gas that is not covered by the diffusor net (28) is concave, the two opposing convex areas of diffusor net that are arranged within the exhaust gas outlet pipe in series, directly one behind the other, touching each other in an approximate middle area.

40. An apparatus as defined in claim 38 or claim 39, characterized in that, as viewed in the direction of the outgoing flow--the first area of diffusor net, including any stabilizing attachments, or guide plates is of stainless steel, and the subsequent area is of a non-rusting steel alloy containing copper, and the last part consisting of a pure copper alloy.

41. An apparatus as defined in one of the claims 35 to 40, characterized in that paddle-like guide baffles (31) are provided in the diffusor net, these allowing the exhaust gas to pass through in a laminar flow and supporting the diffusor net (28).

42. An apparatus as defined in one of the claims 35 to 41, characterized in that the exhaust pipe (26) is fitted with a flame-resistant lining (29) in the area of the diffusor and in a subsequent area that is of approximately equal length.