Towards a zero particle rejection
petrol and diesel engines
In exhaust of a
diesel engine or gasoline,
many particles (1)
| In an efficient particulate
filter (2), more than 99%
of these particles are
|But the particles (3)
which pass the filter
are small particles
(fine particles and
very dangerous for
|This new damp device
(4) retains the
|In order to reject|
Zero particle in
exhaust outlet (5).
|The new device is installed after the particulate filter (DPF) to retain the last particles.|
The housing (1) comprises an inlet (2) and an outlet (3) of the exhaust gases and a particular shape imposing on the exhaust gases passing through it, a forced path (4) which puts the gases and particles they contain with the maximum possible surfaces in the housing.
These surfaces (10) are covered with a liquid on which the particles remain glued and are grouped by the desired displacement of the liquid, a reserve (5) is located at the bottom of the housing (1).
This displacement of the liquid is actuated by gravity and by an electric pump (6) which raises the liquid which is directed towards the walls of the housing by appropriate outlets such as (8).
The gases (9) freed of all or part of the particles escape toward the exhaust outlet (3).
The chosen liquid is castor oil which has some very useful peculiarities in this use:|
- it is very wetting,
- it withstands high temperatures,
- it is with difficulty miscible with water,
- it is a biodegradable vegetable oil, ecological and renewable.
Other liquids may also be suitable.
The European standard imposes a maximum of particles rejected of 4.5 mg per kilometer traveled by an automobile.|
That corresponds to 4.5 grams per thousand kilometers traveled
and 450 grams of particles per 100,000 km traveled.
The weight of these stored particles will not influence the operation of the vehicle.
In the case of a petrol engine, the oil is periodically drained and recycled, as in the case of engine oil drain.
With regard to a diesel engine, after removing enough particles, the castor oil can be drained from the device and mixed with diesel fuel as a part of vegetable oil in the engine fuel, and so the particles are then burned in this engine.
This operation can also be done automatically by periods provided you have a small onboard oil tank,
a suitable fuel filter and injectors that allow it.
|In a variant, |
the housing comprises blades (15) driven in rotation by an electric motor which further increases the contacts between each blade and the gases.
On the other hand the liquid is projected in greater volume of each blade to the walls of the housing which facilitates the ejection of captured particles to the walls and downwards.
The supply of the liquid is done on the one hand on the walls of the case and on the other hand on the blades as in (16).
|Assembly at the end of the exhaust line:|
The engine (1) is equipped with an air inlet (2), an exhaust outlet (3), a catalytic converter (4), a particulate filter (5).
The gases are then cooled in the expansion pipe (6).
The final depollution device (7) precedes the exhaust outlet discharging exhaust gases (8).
Turbo, EGR valve, probes ... are not shown.
In this configuration, the device (7) also acts as a silencer.
As far as the particles are concerned, we can get closer to a total pollution control of the exhaust gases, which is an ecological progress .
On the other hand the vehicles having an initial device of decontamination insufficient can enter the standards thanks to a complementary depollution by the new device.
By equipping its vehicles with such a device, the manufacturer can claim to reduce the risk of triggering asthma, allergies and certain cancers whose fine particles have a cofactor role.
|Other variant of the device|
The housing has at least one baffle (11) which increases the length of the gas path and the area of contact with the walls and surfaces of the housing.
At least one nozzle (12) distributes the liquid on the contact surfaces.
Several jets can be associated as (13).
|Another variant in the same spirit as the variant with rotating blades with vertical axis but here with a horizontal axis.|
At least one of the blades can enter the liquid (bubbling).
It is the electric motor (M) that drives the blades in rotation.
|In another variant, the gases are forced to pass through the liquid at least once as in (18).|
Part of their final course in the housing, as in (19), facilitates the separation of gas and liquid, which remains in the housing.
The forced path of the gases passes through at least one perforated grid (20) on which the liquid flows or which is immersed in the liquid. The gases flowing through the perforations are more easily in contact with the liquid.
|In another variant, the liquid, which may be in the form of gel or glue and disposed on a support (26) wound in
a cassette having two rollers (23) and (29).|
Both rollers are driven in slow rotation by an electric motor and drive the support in the direction of rotation when the internal combustion engine is in operation and produces exhaust gas.
One of the rollers comprises the liquid-coated support and is unwound providing the surface of the support, which may be a canvas or paper, in contact with the particles while the other roll winds the same support at a speed consistent with the unfolding of the first roll so that the support remains sufficiently taut.
Here also the shapes of the housing as (25) constrain the gases to a forced course as in (21), (22) and (24) which makes them come into contact with the support.
When the support is about to be unrolled, an indicator warns the driver of the vehicle that the cassette must be replaced by a blank particle cassette.
In this variant the compartment (28) does not require the presence of the liquid.
The training is not represented.
|In another variant, the two rollers (30) and (31) are connected in rotation by a continuous support (32) which is in permanent contact with the liquid in the compartment (33).|
Thus, as it rotates around the rollers, the continuous support (32) collects particles when it is in contact with the exhaust gases and transfers them to the liquid when it is immersed in the liquid in its lower position of the compartment (33).
It thus regenerates its surface to be optimally effective in the phase of the passage of gases on its surface. Here too, the shapes (34) of the housing force the gases to come into contact with the continuous support (32) as in (35) for better efficiency.
The arrangement of circulation of the continuous support makes that it is not necessary in this variant to replace the continuous support but it will be preferable to periodically drain the liquid.
|Example of combination: The passage through the liquid brakes the passage of gases but the blades compensate by accelerating it.|
The passage of the exhaust gas can even be accelerated, for example, to compensate for other brakes along the entire exhaust pipe.
|In the case of diesel, by integrating a sufficiently large oil tank (about 20 liters) into the vehicle, one could consider replacing the "traditional" particulate filter with this new type of wet filter with a continuous or sequential integration of the oil to the fuel as it is charged in particles and a filling of the liquid tank, for example, every 10 full of fuel.|
A dipstick and a low level indicator installed on the dashboard with a significant limitation of the vehicle speed (degraded mode) if this tank is empty.
Thus, it would be possible to use a diesel vehicle in downtown without emitting particles and even to make short trips without the risk of clogging the particle filter with this type of use even common.
Without emission of benzene, contained in gasoline as an additive, while diesel does not contain it .
This new filter does not impede an electric hybridization of the vehicle, it helps it to run even cleaner.