EP1184626A1 - Method for treating atmospheric pollutions, in particular olfactory pollutions and device for carrying out this method - Google Patents

Abstract

Treating atmospheric pollution, particularly odors, uses a helical device (124) at the end of a mast (122). The device produces an air flow to lift polluted air from ground level and dilutes it by entraining other air and the diluted pollution is dispersed at a higher level. An Independent claim is included for an apparatus for performing the above includes the mast, the helical device and a cylindrical wall around the device to prevent back flow and turbulence at the edges of the device. Preferred Features: The apparatus lifts the air to ≥ 50 m and dilutes it ≥ 10 times. The helical device has a volumetric flow of 200-600 m<3>/s and flow rate of 10-30 m/s. The device is mounted on the mast with 2 or 3 degrees of freedom. The wall tapers down elliptically upstream of the device to produce suction beneath the device. The device is driven by a motor at the bottom of the mast.

Description

The present invention relates to a method for treating atmospheric pollution, in particular olfactory pollution by dilution and dispersion. It also relates to a device for the implementation of said method in the form of a propeller arranged at the end of a mast.

In FIG. 1, there is shown a rack 10 open from a landfill center for waste, in particular household waste, in use, comprising a source 12 of foul smells as well as the iso- concentrations of odors. As can be seen, the odors from odorous molecules present in the air spread in the form of sheets at ground level and their concentration remains relatively high, of the order of 1.5 mg / m ³ , to hundreds meters from the source, or even a kilometer. This constitutes a real annoyance for the residents of such centers, knowing that the threshold for the perception of such odors is much lower than 1 mg / m ³ .

For the treatment of these odors, recourse is generally made to spraying devices which make it possible to nebulize on the waste of masking products. The action is very local and the particles of the products masks fall to the ground quickly letting odors come out again initials.

Furthermore, this odor treatment process is not satisfactory in terms of its effectiveness and its impact on the environment.

In fact, this process only allows the surface layer of the locker. However, in general after treatment, the surface layer is covered by a new layer of waste from which odors emanate foul-smelling untreated, making treatment effectiveness fleeting.

On the other hand, the spraying of products induces runoff at through layers of waste that need to be captured and treated if we do not want to risk polluting the underground and especially the aquifers groundwater. However, the devices to ensure the capture and processing of these runoff is relatively expensive and difficult to implement if the quantities are important. However, to reach a sufficient efficiency threshold, it such quantities should be used.

According to the prior art, there are more or less realistic devices allowing the treatment of atmospheric pollution, described in particular in patent applications WO99 / 54572 and US 3,489,072.

These devices use the phenomenon of dispersion to treat the air pollution using large chimneys which discharge into altitude smoke or the like.

However, the devices described are generally very expensive, difficult to work and relatively ineffective due to the amount of air treated and their very localized action, the latter can only treat occasional and non-surface or volume pollution such as odors emanating from a landfill locker.

Also, the present invention aims to overcome the drawbacks of the art by proposing a new pollution treatment process atmospheric and in particular olfactory pollution, effective, simple to to implement, relatively inexpensive compared to existing solutions and which ensures efficient treatment of a large quantity of air on a relatively large area.

To this end, the invention provides a method of treating pollution atmospheric, in particular of olfactory pollution, characterized in that it consists in using a device comprising a propeller arranged at the end a mast, capable of generating a suction flow below the propeller likely to suck polluted air at ground level and an upward flow drive above the propeller to treat the air polluted by dilution, that is to say by brewing it with a large volume of less or unpolluted air, and by dispersion, that is to say by rejecting it at altitude.

According to another characteristic, the ejection speeds and the flow rate of the device are adjusted to reach a suitable dispersion altitude varying for example from 50 to 200 m and a dilution coefficient at least equal to 10 and possibly reaching 10 ⁶ . Preferably, the device must have a flow rate at the propeller varying from 200 to 600 m ³ / s and an ejection speed varying from 10 to 30 m / s.

The invention also provides a device for implementing the previously defined process, characterized in that it comprises a mast the end of which is attached a propeller head on which is mounted in rotation a propeller, as well as means for driving in rotation of the propeller.

Advantageously, it includes non-return means in the form a cylindrical wall arranged concentrically with the propeller, susceptible to prevent the appearance of swirling flows at the ends of the blades said propeller. This arrangement improves the efficiency of the propeller and reduce noise.

Preferably, the wall is in the form of a convergent so as to accelerate the ejection flow and create a greater depression under the propeller.

According to a preferred embodiment, the convergent has a shape elliptical and includes, at its upstream end according to the air flow, a flange substantially perpendicular to said flow, so as to prevent the appearance separation of the flow from the wall at the inlet of the convergent.

According to another characteristic of the invention, the mast is mounted on a mobile chassis made up of several sections so that it can be fold, to facilitate the movement of the assembly.

According to one embodiment, the mast comprises a first section secured to the chassis, a second section articulated with respect to the first section around an axis substantially perpendicular to the longitudinal axis of the chassis thanks to an actuator and a third section, at the free end which is fixed the propeller head, and articulated relative to the second section around an axis substantially parallel to the longitudinal axis thanks possibly to an actuator.

• la figure 1 est un schéma montrant les iso-concentrations d'odeurs émanant d'un casier ouvert d'un centre d'enfouissement de déchets sans traitement desdites odeurs,
• la figure 2 est un schéma montrant les iso-concentrations d'odeurs émanant d'un casier ouvert d'un centre d'enfouissement de déchets traitées selon le procédé de l'invention,
• la figure 3 est une vue schématique illustrant l'aspiration générée par l'hélice sous cette dernière,
• la figure 4 est une vue schématique illustrant le phénomène d'entraínement présent au-dessus de l'hélice,
• la figure 5 est un schéma montrant les vitesses et le débit du flux au-dessus, de l'hélice à différentes altitudes,
• la figure 6 est une vue en élévation latérale du dispositif de l'invention,
• la figure 7 est une vue de dessus du dispositif en position déployée,
• la figure 8 est une vue en élévation latérale du dispositif en position repliée,
• la figure 9 est une vue de détail montrant la tête de l'hélice,
• la figure 10 est une vue schématique d'une variante améliorée du dispositif,
• la figure 11 est une coupe du dispositif de la figure 10, et
• la figure 12 est une demi-section d'un convergent.

Other characteristics and advantages will emerge from the description which follows of the process and the device of the invention, description given by way of example only and with reference to the appended drawings in which:

• FIG. 1 is a diagram showing the iso-concentrations of odors emanating from an open locker of a landfill center without treatment of said odors,
• FIG. 2 is a diagram showing the iso-concentrations of odors emanating from an open rack of a landfill center for waste treated according to the method of the invention,
• FIG. 3 is a schematic view illustrating the suction generated by the propeller under the latter,
• FIG. 4 is a schematic view illustrating the drive phenomenon present above the propeller,
• FIG. 5 is a diagram showing the speeds and the flow rate of the flow above, of the propeller at different altitudes,
• FIG. 6 is a side elevation view of the device of the invention,
• FIG. 7 is a top view of the device in the deployed position,
• FIG. 8 is a side elevation view of the device in the folded position,
• FIG. 9 is a detailed view showing the head of the propeller,
• FIG. 10 is a schematic view of an improved variant of the device,
• FIG. 11 is a section through the device of FIG. 10, and
• Figure 12 is a half section of a convergent.

To illustrate and describe the process of the invention, we have chosen to apply it to the treatment of foul smells coming from a center landfill. It is obvious that this process can be applied to other types of air pollution. This process is more particularly suitable for treating diffuse pollution of the surface type or volume.

As we have seen above, there is shown in Figure 1 an open bin 10 of a landfill center for waste, in particular household waste, in use, comprising a source 12 of odors foul-smelling as well as the odor iso-concentration curves, referenced 14, 15, 16, 17, 18 and corresponding respectively to 500 mg / m ³ , 20 mg / m ³ , 10 mg / m ³ , 2 mg / m ³ and 1.5 mg / m ³ .

As can be seen, the odors from odorous molecules present in the air spread at ground level and their concentration remains relatively high, of the order of 1.5 mg / m ³ , hundreds of meters from the source. This constitutes a real annoyance for the residents of such centers, schematically represented in 20, knowing that the threshold for perception of such odors is 1 mg / m ³ in general but varies considerably depending on the type of molecule.

According to the method of the invention, the polluted air is treated by dilution, that is to say by brewing it with a large volume of less or unpolluted air, and by dispersion, that is to say by rejecting it at altitude.

In FIG. 2, an open locker 10 is schematically represented with a source 12 of foul smells as well as the iso-concentration curves of smells, referenced 22, 23, 24, 25, 26 and corresponding respectively to 0, 1 mg / m ³ , 0.09 mg / m ³ , 0.08 mg / m ³ , 0.07 mg / m ³ and 0.06 mg / m ³ .

So we see that the odors from odorous molecules present in the air no longer spread at ground level but are discharged at an altitude of the order of 50 to 200 m, and that their concentration in altitude is greatly reduced thanks to the dilution phenomenon.

We can also note that the residents 20 are no longer inconvenienced by this olfactory pollution.

To stir and disperse the air, a device 28 called "pulser" comprising a propeller 30 disposed at the end of a mast 32.

Compared to existing methods and devices, the method of the invention allows to treat a larger volume of polluted air. For example, the process of the invention makes it possible to effectively treat odors emanating from a locker with an area of 0.5 to 1 ha.

These convincing results are obtained thanks to the "pulser" which generates a suction flow 33 below the propeller capable of sucking the polluted air at ground level and an upward drive flow 34 above the propeller, visible in Figures 3 and 4, capable of rejecting air at an altitude of from 50 to 200 m, with a consequent increase in the flow of treated air above the propeller thanks to the drive phenomenon. Speed ejection and the flow rate of the "blower" are adjusted to preferably obtain a dispersion altitude of at least 50 m and a dilution coefficient of at least equal to 10.

In FIGS. 3 and 4, the different types have been represented in a separate manner effects generated by the "kicker" of the invention. It is obvious that in reality these two suction effects below the propeller 30 and training above of the propeller are combined. These two phases are followed by a phase of dispersion which cannot be represented on the scale of the drawing because it concerns a very large volume.

In Figure 3, there is shown the suction flow 33 produced below the propeller 30 as well as the upward drive flow 34 generated above the propeller. This suction effect makes it possible to stir a large volume of air of the order of 2,000,000 m ³ / h and to greatly reduce the concentration of odorous molecules by dilution, said concentrations being divided at least by 10.

In Figure 4, we showed the upward flow of training 34 produced above the propeller 30. This entrainment effect generated by the swirling currents present at the limits of flow 34 increases strongly the volume of air treated.

As can be seen in Figure 4, this training effect allows treat a large area thanks to the air currents that occur in margin of the device. This allows a larger volume of air to be treated and dilute the odor molecules even more.

In FIG. 5, the velocities and the flow above the propeller at different altitudes A0 at the propeller, A1 10 m, A2 50 m and A3 100 m above the propeller.

The values given in the table below are given by way of example for a 5.4 m diameter propeller, placed 10 m from the ground, rotating at 600 rpm. Altitude (m) Flow (m ³ / s) Maximum speed (m / s) A0 0 500 30 A1 10 1,500 25 A2 50 2,500 10 A3 100 3,000 5

As can be noted, the flow is multiplied by 5 to 100 m above of the propeller, which results in an increase in the volume of air treated and greater dilution.

To ensure efficient operation, the "blower" must have a flow rate at the propeller varying from 200 to 600 m ³ / s and an ejection speed varying from 10 to 30 m / s.

A device 28, called a "pulser", more particularly suitable for the implementation of the method of the invention is shown in FIG. 6.

It mainly comprises a propeller 30 disposed at the end of a mast 32.

This device also comprises a movable chassis 36 supporting the mast 32 at the end of which is attached a propeller head 38 on which is rotationally raising the propeller 30, as well as means 40 for driving in rotation of said propeller 30.

Preferably, the chassis 36 comprises a platform 42 capable of to be lashed to a truck like a dumpster. For this purpose, the platform includes coupling means 44 which are not detailed because within the reach of those skilled in the art and adapted according to the type of towing vehicle.

For a better seat, especially during operation, the platform 42 comprises means 46 for supporting the ground, preferably under form of four reinforcement legs capable of occupying two positions, one first deployed position, as illustrated in FIG. 7, in which these legs rest on the ground to strengthen the seat of the device, and a second folded position, as illustrated in FIG. 8, in which they are arranged above the platform 42, in particular at the time of transport.

The mast 32 is made up of several sections so that it can be fold, to facilitate the movement of the assembly. It includes a first section 48 secured to the chassis 36, a second section 50 connected to the first 48 and a third section 52 connected to the second 50 at the free end of which is fixed the propeller head 38.

To fold the mast 32, the second section 50 is articulated relative to the first section 48 around an axis 54 substantially perpendicular to the axis longitudinal 56 (see figure 7) of the chassis thanks to an actuator 58, a jack for example. Likewise, the third section 52 is articulated relative to the second section 50 around an axis 60 substantially parallel to the axis longitudinal 56 possibly thanks to an actuator not shown.

This arrangement makes it possible to obtain a more compact device in position folded as illustrated in Figure 8.

The means 40 for rotating the propeller comprise according to a preferred embodiment, a motor 62, preferably hydraulic, and transmission means 64 consisting of shafts and angle references, not detailed because within the reach of the skilled person.

A drive by hydrostatic transmission is particularly suitable instead of a mechanical transmission for lead important powers and this training remains the same very easy to install on an articulated head.

The propeller head 38 is shown in detail in Figure 9. It should allow at least two degrees of freedom, and preferably three, a first rotation around the longitudinal axis 66 of the mast, a second rotation around an axis 68 substantially perpendicular to the axis 66, and possibly a third rotation around the longitudinal axis 70 of the blades 72, this in order orient the propeller ejection flow 30 as well as possible.

The propeller head 38 comprises a first part 74 mounted for rotation relative to the mast 32 around the axis 66 by means 76, a second part 78 rotatably mounted relative to the first part 74 around the axis 68 by means 80, and a blade holder 82 rotatably mounted by relative to the second part 78 around the axis of rotation 84 of the propeller.

The means 76 for rotating include a notched crown 86 secured to the frame and a pinion 88 secured to a plate 90 connected to the part lower part of the first part 74 of the head. So by meshing on the crown 86, the pinion 88 rotates the first part 74.

The means 80 for rotating comprise a fixed window 92 the second part 78 of the head, extended by trees 94, diametrically opposed, mounted for rotation in bearings 96 of axis, the axis of rotation 68, integral with the first part 74 of the head. The rotation around of axis 68 is obtained by an actuator 96 connecting the telescope 92 to the first part 74.

The blade holder is connected to the second part 78 according to a mode of realization thanks to an axis bearing, the axis of rotation 84 of the propeller, and supports two blades 72. preferably, these blades 72 are removable to be disassembled quickly and facilitate the transport of the whole.

According to another characteristic of the invention, the orientation of the blades 72 can be adjusted by means 98 of adjustment. According to a mode of embodiment not shown, the shaft of each blade is extended by an ear set in motion by an actuator, a jack for example.

An improved variant of the device is shown in Figures 10 to 12, making it possible to reduce the appearance of swirling flows at the ends blades likely to cause hissing and producing an effect increased suction sufficient to take off the laminated flows at ground level, especially in the presence of wind.

As illustrated by FIGS. 10 and 11, according to the invention, the device includes a frame 120 on which is fixed a mast 122 at the end of which is added a propeller 124 as well as non-return means in the form of a cylindrical wall 126 disposed concentrically with the propeller 124, likely to prevent the appearance of swirling flows. This arrangement It also improves the efficiency of the propeller and reduces noise.

Advantageously, the wall 126 is shaped so as to converge to accelerate the ejection flow and create a greater depression under propeller 124, capable of taking off the laminated fluxes at ground level, even in the presence of wind.

According to a preferred embodiment, the propeller 124 comprises blades 128 attached to a hub 130 linked to the shaft of a 136. motor. complement, radial arms 132 are provided as a means of connection between the wall 26 and the mast or the motor.

According to a characteristic of this arrangement, the motor 136 is arranged at the propeller hub which helps to simplify the device especially in terms of training means and to improve its compactness.

As an indication, the propeller 124 has a diameter varying from 1 to 4 m, is arranged at a height varying from 3 to 7 m and rotates at a speed varying from 600 to 2000 rpm.

As illustrated in FIG. 12, the convergent preferably has a elliptical shape, and includes at its upstream end according to the air flow a collar 134 substantially perpendicular to said flow. This collar 134 provides better air guidance and prevents the appearance of delamination of the flow of the wall at the inlet of the convergent 126.

This variant can use a frame, a mast, and a propeller head as described previously.

Of course, the invention is obviously not limited to the mode of realization represented and described above, but on the contrary covers all variants, in particular with regard to the drive means 40 propeller rotation, the number and dimensions of the blades, the positioning of the propeller as well as the form and the means of connection to the mast of the convergent.

As for applications, one can also apply such an arrangement to sewage treatment plant lagoons, spreading slurry on land agricultural or industries that generate particularly stubborn odors like rubber factories.

Claims (12)

Method for treating atmospheric pollution, in particular olfactory pollution, characterized in that it consists in using a device (28) comprising a propeller (30, 124) disposed at the end of a mast (32, 122), susceptible generate a suction flow below the propeller capable of sucking the polluted air at ground level and an upward flow of entrainment above the propeller in order to treat the polluted air by dilution, it that is to say by brewing it with a large volume of less or unpolluted air, and by dispersion, that is to say by rejecting it at altitude. Treatment method according to claim 1, characterized in that the ejection speeds and the flow rate of the device are adjusted to reach a dispersion altitude of at least 50 m and a dilution coefficient at least equal to 10. Treatment method according to claim 1 or 2, characterized in that the device must have a flow rate at the helix varying from 200 to 600 m ³ / s and an ejection speed varying from 10 to 30 m / s. Device for implementing the method according to any one of Claims 1 to 3, characterized in that it comprises a propeller (30, 124) attached to the end of a mast (32, 122) as well as non-return means in the form of a cylindrical wall (126) arranged concentrically with the propeller (30, 124), capable of preventing the appearance of swirling flows at the ends of the blades of said propeller. Device according to claim 4, characterized in that the wall (126) is in the form of a convergent so as to accelerate the ejection flow and create a greater depression under the propeller (124). Device according to claim 5, the convergent comprises, at its upstream end according to the air flow, a collar (134) substantially perpendicular to said flow, so as to prevent the appearance of a separation of the flow from the wall at the inlet of the convergent (126). Device according to claim 5 or 6, characterized in that the convergent has an elliptical shape. Device according to one of claims 4 to 7, characterized in that the propeller (30) is integral with a propeller head (38) capable of allowing at least two degrees of freedom. Device according to claim 8, characterized in that the propeller head (38) comprises a third degree of freedom, a rotation about the longitudinal axis (70) of the blades (72), ensuring the adjustment of the orientation of said blades blades. Device according to any one of claims 4 to 9, characterized in that the motor (136) capable of driving the propeller in rotation is arranged at the hub of the latter. Device according to any one of claims 4 to 10, characterized in that the mast (32) is mounted on a movable frame (36) and consists of several sections so as to be able to fold to facilitate the movement of the assembly. Device according to claim 11, characterized in that the mast (32) comprises a first section (48) integral with the chassis (36), a second section (50) articulated relative to the first section (48) about an axis ( 54) substantially perpendicular to the longitudinal axis (56) of the chassis thanks to an actuator (58) as well as a third section (52), at the free end of which the propeller (30) is fixed, and articulated with respect to to the second section (50) around an axis (60) substantially parallel to the longitudinal axis (56) possibly thanks to an actuator.

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