EP3856393A1

EP3856393A1 - Device for protecting fume intake into a scrubber, as well as cleaning facility comprising such a device

Info

Publication number: EP3856393A1
Application number: EP19773829.7A
Authority: EP
Inventors: Bernard Siret; Anthony JIGOREL; Fabrice Gourmelon
Original assignee: LAB SAS
Current assignee: LAB SAS
Priority date: 2018-09-26
Filing date: 2019-09-25
Publication date: 2021-08-04
Also published as: FR3086188B1; CN112888495B; FR3086188A1; WO2020064795A1; CN112888495A

Abstract

This protection device (10) is suitable for being arranged inside a scrubber and including an apical body (11) which, when the protection device is installed in the scrubber, is placed above the downstream mouth of a vertical duct for admitting fumes into the scrubber, so as to protect the duct against the introduction of water while allowing the fumes leaving the duct to pass. In order for this protection device to perform particularly well, an upper face (12) of the apical body is provided with water collection channels (14), which each extend lengthwise from a central region (11 A) of the apical body, around which the channels are distributed, to a periphery (11 B) of the apical body, which is completely occupied by the channels. Each channel has, over its entire length, a cross-section that is substantially triangular and whereof the lower apex defines a bottom edge (15) along the channel. The respective bottom edges of the channels rest on a conical surface that converges upwards and the apical angle of which is between 90 and 170°.

Description

Device for protecting fume intake into a scrubber, as well as cleaning facility comprising such a device

The present invention relates to a device for protecting fume intake into a scrubber. It also relates to a facility for wet cleaning exhaust fumes from an engine of a marine vessel, this facility comprising such a protection device.

Marine vessels, whether passenger ships or other vessels, use fuel oil as fuel for the diesel engines propelling them. This fuel oil contains up to 5 wt% of sulfur, most often between 0.5 and 3.5 wt%. During the combustion process in the engines, this sulfur is converted into sulfur dioxide (S0₂). As a result, the exhaust fumes from these engines are acidic. Maritime regulations tend to limit the emissions of sulfur dioxide from fumes discharged into the atmosphere by ships. Ships must therefore incorporate means for reducing these sulfur dioxide emissions. Several solutions can be considered.

It is first possible to reduce the sulfur content of the fuel oil used, or even to use liquefied gas, which immediately leads to a reduction in sulfur dioxide emissions. However, fuel oil with a very low sulfur or liquefied gas content is expensive, such that this approach is not very economical.

Another approach consists of using a wet scrubber, in which an ad hoc scrubbing liquid is used, typically with a base of seawater, the natural alkalinity of which is used to neutralize sulfur dioxide. Subsequently, in the rest of the present document, this scrubbing liquid is called "water", with the understanding that this term "water" corresponds to the aqueous liquor, in the liquid state, used to purify fumes in a scrubber, this water typically being seawater, to which a neutralizing reagent may have been added such as sodium hydroxide (NaOH), magnesia (MgO, Mg(OH)₂) or lime (Ca(OH)₂), and which may also contain salts, resulting from the purification of the fumes, and other solids.

In practice, the use of scrubbers on board ships is faced with particular constraints. The space on board ships is limited, which requires great compactness of the scrubbing facilities. Furthermore, several operating modes of the scrubbers must be provided, in particular an open loop mode, in which a large quantity of seawater is admitted into the scrubber, from which it is discharged without recycling, before being discharged after any post-treatment, and a closed loop mode, in which the majority of the water leaving the scrubber is recycled and usually doped with an alkaline reagent supplement, only a minimal purge being discharged. Furthermore, the pressure drop through the scrubber must be very low, since beyond a possible quenching of the engine, the energy efficiency, for example in kilowatts per kilogram of fuel oil, decreases greatly when the head losses increase, which is not economically desirable. Lastly, the maintenance and upkeep operations are more difficult to carry out on a marine vessel than on a land-based unit. Furthermore, among the specific constraints of marine scrubbers, irrespective of the operating conditions of the latter, whether running, stopped or during transitional periods, so-called "water entry" issues are encountered, i.e., related to the passage or flow of water from the scrubber toward the equipment located upstream from the latter, and particularly toward the duct admitting the fumes to be cleaned into the scrubber. Indeed, water entry must be avoided because the intrusion of water into the duct admitting the fumes into the scrubber will raise corrosion problems of the boilers and heat recovery units, located upstream from the scrubbers, or even safety problems with respect to the engine itself, especially for so-called "in-line" scrubbers whereof the intake for the fumes to be cleaned is located below the scrubber. In practice, the scrubbers operate with between 500 and 4000 m³/h of water, depending on the design, the required performance and the power of the engine; at the same time, a little fraction of water as small as several liters per hour of water being introduced into the duct for the fumes is not tolerable. One therefore uses protection devices that generally assume the form of cones or double cones, in particular in the form of a Chinese hat, i.e., cones whereof the tip is pointed upwards. However, the existing protection devices are insufficient in light of the very, very small allowable water entry, in particular during the transitional operating periods of the scrubbers.

In order to understand this water entry problem issue clearly, reference may be made to figure 1 . Figure 1 shows a very simplified view of a marine scrubber 1 in which exhaust fumes F from one or several diesel engines of a ship are introduced into the bottom of the scrubber 1 , while being allowed therein through a vertical duct 2, which passes through the bottom of the scrubber while being generally centered on the latter. At the top of the inside of the scrubber, a distribution device 3 distributes water, for example by spraying, this water being, in figure 1 , shown in the form of a rain P, this depiction being only symbolic in that the water falls above all in the form of drops and not necessarily vertically. In contact with the water, the fumes F that circulate from bottom to top inside the scrubber 1 are purified by transfer of the sulfur dioxide that they contain into the water coming from the distribution device 3 and circulate, by gravity, from top to bottom inside the scrubber 1 , this water next being discharged from the bottom of the scrubber via an outlet 4, if applicable while being partially recycled to the distribution device 3 in a manner not shown in figure 1 . In order to prevent part of the water distributed by the distribution device 3 from entering the duct 2, a protection device 5 is arranged inside the scrubber 1 between the downstream mouth of the duct 2 and the distribution device 3, while being placed vertically above the downstream mouth of the duct 2: the protection device 5 allows the fumes F that leave the duct 2 to pass, while protecting this duct against the introduction of water. In figure 1 , the protection device 5 is shown in the form of a Chinese hat, but other arrangements are possible. Various examples are proposed in WO 2014/128261 , WO 2017/198653 and EP 3,260,187.

With the known embodiments of the protection device 5, the effectiveness of the latter can be substantially compromised due to two troublesome phenomena, particularly in the transitional operating periods of the scrubber 1.

These phenomena are related to a liquid film E1 that is formed, on the upper face of the protection device 5, by the rain water P reaching the protection device 5. This film E1 is relatively thin, while having a thickness that is usually between 1 and 5 mm and that depends on the specific geometry and the slope of the upper face of the protection device 5, as well as the flow of water introduced by the distribution device 3. In all cases, this film E1 is distributed over the entire upper face of the protection device 5 and, by flow, reaches the entire periphery of this face. The first phenomenon that can occur is that a small portion of the liquid film E1 remains, by capillarity, adhered to the lower rim of the protection device 5 and migrates toward the central axis of the scrubber 1 along the lower face of the protection device, until unsticking from this lower face vertically over the duct 2, in the form of drops E2 that can then enter, by gravity, inside the duct 2. The second phenomenon that can occur is that, due to its small momentum, the liquid film E1 leaves the protection device 5 at the periphery of the upper face of the latter, while forming one or several thin water curtains E3 for which it is easy, for movements of fumes symbolized by the arrows T, to extract a fraction carried to the inside of the duct 2. The aforementioned movements of fumes T can correspond to recirculation movements of the fumes F inside the scrubber 1 , or to convective movements of fumes that appear in the transitional operating periods of the scrubber.

It will therefore be understood that the current embodiments of the protection device 5 are insufficient to completely prevent the entry of water in the duct 2, such a water entry being intolerable once it exceeds several liters per hour, or an infinitesimal part of the water brought in by the distribution device 3, typically less than 1 /50000^th of the quantity of water distributed by this device 3.

The aim of the present invention is to propose a higher performing protection device.

To that end, the invention relates to a device for protecting fume intake into a scrubber, as defined in claim 1.

The invention also relates to a facility for wet cleaning exhaust fumes from an engine of a marine vessel, as defined in claim 10. Owing to the invention, the water which, coming from the distribution device, reaches the upper face of the apical body of the protection device according to the invention, such as the rain water P of figure 1 , becomes concentrated in the bottom of each channel of the protection device, streaming over the lateral slopes of each channel up to the bottom edge of the channel. The water is thus collected in the bottom of each of the channels and forms a stream that flows therein in thick streams, like at the bottom of the bed of a torrent, from the central region of the apical body to the periphery of the latter where the aforementioned thick streams leave, with a large momentum, the upper surface of the apical body at the respective ends of these channels. Of course, the geometric specificities of the channels, in particular their depth and their opening angle, are provided accordingly by one skilled in the art, so that the water that falls on the upper face of the apical body and that may have a flow rate of several hundred cubic meters per hour in a marine scrubber, is concentrated in the form of the aforementioned thick streams by the channels. Thus, although the rain water P reaches the apical body over its entire upper surface, the water is concentrated entirely in the bottom of the channels and leaves this apical body, in the form of the aforementioned thick streams, exclusively at the ends of the bottom edges of the channels, the accumulation of these ends representing only a small portion of the periphery of the apical body. Due to their thickness and their momentum, these streams of water leave the apical body of the protection device according to the invention as liquid jets with a high speed and going far, while remaining globally in thick streams, somewhat like water coming from a garden hose. Then, since these streams of water immediately escape from the apical body of the protection device while leaving the latter, any capillarity phenomenon that would result in the formation of drops like the drops E2 of figure 1 is greatly limited. Furthermore, these thick streams of water, which loosen from the protection device with a large momentum, offer less sticking to the movements of fumes like the movements T of figure 1 , compared to the thin water curtains E3 of figure 1 . Thus, the two aforementioned phenomena, which are detrimental to the effectiveness of the known embodiments of the protection device 5 of figure 1 , are thwarted by the invention. The performance of the protection device according to the invention is thus remarkable, as observed by the inventors in the laboratory and in full-scale facilities.

Optional advantageous features of the protection device and the cleaning facility according to the invention are specified in the other claims.

The invention will be better understood upon reading the following description, provided solely as an example and done in reference to the drawings, in which:

- figure 1 is a schematic view of a facility for treating fumes, which belongs to the prior art and has been described above; - figure 2 is a perspective view of a protection device according to the invention;

- figures 3 and 4 are elevation views along arrow III of figure 2 and arrow VI of figure 3, respectively; and

- figures 5 and 6 are views similar to figure 3, respectively illustrating two embodiment options for the protection device according to the invention.

Figures 2 to 4 show a protection device 10 making it possible to protect the intake of fumes into a scrubber. The protection device 10 is provided to be used in the cleaning facility shown in figure 1 , in place of the protection device 5. Thus, within a facility for wet cleaning exhaust fumes from an engine of a marine ship, the protection device 10 is associated with the scrubber 1 and the distribution device 3, described in detail above, such that when this cleaning facility is operational, the protection device 10 and the distribution device 3 are installed inside the scrubber, the distribution device 3 being located above the protection device 10.

Given the usage context of the scrubber 1 , namely on a marine ship, the inner diameter of this scrubber is usually at least two meters.

As clearly shown in figures 2 to 4, the protection device 10 includes an apical body 1 1 , which, when the protection device 10 is installed in the scrubber 1 , constitutes the uppermost part of this protection device. Within the purification facility, the apical body 1 1 is placed vertically above the downstream mouth of the vertical duct 2 for the intake of fumes F into the scrubber 1 , so as to protect this duct against the introduction of water while allowing the fumes leaving the duct 2 to pass: to that end, the rain water P coming from the distribution device 3 falls under the effect of gravity onto an upper face 12 of the apical body 1 1 , while a lower face of the apical body 1 1 is vertically distant from a downstream mouth of the duct 2 such that the fumes F leaving the duct can pass between this downstream mouth and the lower face of the apical body 1 1 to rejoin the rest of the inside of the scrubber 1.

In practice, still in light of the implementation context of the invention, the vertical projection of the upper face 12 of the apical body 1 1 represents a significant fraction, around 40% or more, of the inner cross-section of the scrubber 1.

In the exemplary embodiment considered in the figures, the apical body 1 1 defines a central axis Z-Z that traverses the upper face 12 of the apical body 1 1 in a central region 1 1 A of the latter. When the protection device 10 is installed in the scrubber 1 , the axis Z-Z extends vertically and is advantageously concentric with the duct 2.

In practice, the protection device 10 includes fastening means 13 making it possible to secure the protection device 10 fixedly to the inside of the scrubber 1. In the exemplary embodiment considered in the figures, these fastening means 13 include a flange suitable for being fixedly attached around the apex of the duct 2, and feet connecting the aforementioned flange to the apical body 1 1 . Of course, other embodiments can be considered for the fastening means 13, the latter not being limiting with respect to the invention.

As clearly shown in figures 2 to 4, the upper face 12 of the apical body 1 1 is provided with channels 14 delimited by the apical body 1 1. Each channel 14 extends lengthwise substantially rectilinearly, from the central region 1 1 A of the apical body 1 1 to a periphery 1 1 B of the apical body, the channels 14 being distributed around the central region 1 1 A. In the exemplary embodiment considered in the figures, each channel 14 extends lengthwise radially to the axis Z-Z, from an end that is close to the axis Z-Z to an opposite end located on the periphery 1 1 B of the apical body 1 1. The shape and expanse of the central region 1 1 A of the apical body 1 1 from which the channels 1 1 extend are not limited to the example considered in the figures. Conversely, in all cases, the periphery 1 1 B of the apical body 1 1 is occupied completely by the channels 1 1 , this periphery 1 1 B thus being distributed into portions following one another around the apical body 1 1 , each of these portions being occupied by one of the channels 14, as clearly shown in figure 4.

In the exemplary embodiment considered in the figures, the channels 14 are identical to one another and are provided in eight copies, as clearly shown in figure 4. This being the case, in a variant that is not shown, a larger or smaller number of channels 14 can be considered, an advantageous size being that six to eighteen channels 14 are provided, preferably six to twelve channels 14.

As clearly shown in figures 2 and 3, each channel 14 has, in cross-section, a triangular section whereof a first of the three apices is located vertically lower than the other two apices when the protective device 10 is installed in the scrubber 1. In other words, each channel 14 has a triangular vertical section, with a tip oriented downwards. The triangular shape of the cross-section of each channel 14 is present over the entire length of the channel, having noted that, in the exemplary embodiment considered here, it is advantageously provided that for each of the channels 14, this triangular section increases as one travels over the channel from the central region 1 1 A to the periphery 1 1 B of the apical body 1 1 .

In all cases, the first apex of the triangular shape of the cross-section of each channel 14 defines a bottom edge 15 along this channel. Likewise, the other two apices of the triangular shape of this cross-section of each channel 14 each define a top edge 17 along the channel. For each channel 14, each of the top edges 17 is connected to the bottom edge 15 by a lateral slope of the channel. Along each channel 14, the bottom edge 15 is located vertically lower than each of the top edges 17. The corresponding difference in vertical separation characterizes the depth of the channel 14, which, at any point along the length of the channel, can be measured vertically between the bottom edge 15 and the top edges 17. In the exemplary embodiment considered here, it is advantageously provided that the depth of each channel 14 increases as one flows through the channel from the central region 1 1 A to the periphery 1 1 B of the apical body 1 1 . In figure 3, this depth at the periphery 1 1 B of the apical body 1 1 has a value labelled D: according to an advantageous sizing, this value D is at least 70 mm. In practice, in particular in connection with the embodiment specificities of the channels 14, it will be understood that the value of the depth along the channels can be connected to the number of channels 14.

The triangular section of each channel 14 has, at its apex located on the bottom edge 15 of this channel, an angle, which is denoted a in figure 3 and which characterizes the opening of the channel. According to an advantageous sizing, this angle a is between 30 and 120°, preferably between 60 and 90°. In practice, in particular in connection with the embodiment specificities of the channels 14, it will be understood that the value of the angle a can be connected to the number of channels 14.

Furthermore, the respective bottom edges 15 of the channels 14 rest on a conical surface, which, when the protection device 10 is installed in the scrubber 1 , converges upwards and the apical angle of which is between 90 and 170°, preferably between 100 and 140°. In practice, the aforementioned conical surface, on which the bottom edges 15 rest, can be fictitious in that this conical surface does not constitute a material or physical continuity, but simply designates a geometric surface. In the exemplary embodiment considered in the figures, the aforementioned conical surface is substantially centered on the axis Z-Z. In all cases, each of the bottom edges 15 thus runs rectilinearly and inclined relative to the horizontal, from the central region 1 1 A to the periphery 1 1 B of the apical body 1 1 , having noted that these bottom edges 15 come together, without necessarily being concurrent, at the central region 1 1 A, while they intersect the periphery 1 1 B of the apical body 1 1 at respective ends 16 of these bottom edges, opposite the central region 1 1 A.

According to one preferred embodiment, which is implemented in the example considered in the figures, the respective ends 16 of the bottom edges 15 are located on a circle C16, as clearly visible in figure 4. In practice, still in light of the implementation context of the invention, the diameter of this circle C16 is typically more than a meter.

Within the cleaning facility, this circle C16 is provided to be substantially concentric to the duct 2 and has a diameter strictly larger than the inner diameter of this duct 2 such that the apical body 1 1 sufficiently covers, projected vertically, the downstream mouth of the duct 2, without causing an excessive head loss for the fumes F leaving this duct. More specifically, the diameter of the circle C16 is advantageously between 1 .1 and 2 times the inner diameter of the duct 2, preferably between 1 .25 and 1.65 times the inner diameter of the duct 2. This being the case, and as clearly shown in figure 4, the vertical projection of the periphery 1 1 B of the apical body 1 1 is not necessarily circular, due to the embodiment specificities of the channels 14.

When the protection device 10 is installed in the scrubber 1 and, inside the scrubber, the rain water P coming from the distribution device 3 reaches the upper face 12 of its apical body 1 1 , the water streams over the lateral slopes of each of the channels 14, from the top edges 17, to become concentrated in the bottom of each channel, along the bottom edge 15 of the latter. Thus, the channels 14 collect all of the water on the upper face 12 of the apical body 1 1 of the protection device 10. The incline of the bottom edges 15 causes the collected water to flow in the bottom of each channel 14, from the central region 1 1 A to the periphery 1 1 B of the apical body 1 1. Due to the concentration of the water in the bottom of the channels 14, this water flows along each of the bottom edges 15 in the form of a thick stream, which reaches the end 16 of the bottom edge 15 with a high speed and therefore a large momentum. Each of the thick streams of water reaching the end 16 of the corresponding bottom edge 15 leaves the apical body 1 1 while staying in a thick stream, immediately and cleanly loosening the apical body 1 1 and carrying far away with respect to the latter. Outside the respective ends 16 of the bottom edges 15 of the channels 14, the periphery 1 1 B of the apical body 1 1 is not wetted in that the water having reached the upper face 12 does not leave the apical body 1 1 , since this water has become concentrated in the bottom of the channels 14. In other words, the water reaching the upper face 12 of the apical body 1 1 leaves the latter only through the ends 16 of the bottom edges 15 of the channels 14, with a large momentum.

In practice, inasmuch as, in cross-section at the scrubber 1 , the protection device 10 occupies a substantial fraction of the inside of the scrubber, a similar fraction of the rain P reaches the upper surface 12 of the apical body 1 1 as described just above. Still in light of the implementation context of the invention, this means that the upper face 12 of the apical body 1 1 thus typically receives several hundred cubic meters of water per hour.

Figure 5 illustrates an optional development of the protection device 10 of figures 2 to 4. According to this optional development, the protection device 10 includes, at the base of its apical body 1 1 , a collar 18 fastened to the apical body 1 1 so as, when the protection device 10 is installed in the scrubber 1 , to be arranged below this apical body, while extending substantially vertically from the lower face of the apical body 1 1 over a height h of between 15 and 75 mm and while being located completely inside the vertical projection of the apical body 1 1 . The collar 18 thus makes it possible to interfere with any flows of water coming from the apical body 1 1 , in order to loosen the latter, and it prevents any potential migration of water over the lower face of the apical body 1 1 . In the exemplary embodiment considered in figure 5, the collar 18 is cylindrical, while having an outer diameter that is advantageously between 0.86 and 0.985 times the diameter of the circle C16.

Figure 6 illustrates another optional development of the protection device 10 of figures 2 to 4, this optional development further being able to be combined with the collar 18 of figure 5. Thus, the protection device 10 of figure 6 includes a deflector 19 having a cone shape or a pyramid shape with four, six or eight sides, which, at its apex, is truncated and has a through opening having a diameter equivalent to at least 100 mm. The aforementioned equivalent diameter is conventionally defined as the ratio between four times the surface of the through opening and the perimeter of the latter. In the exemplary embodiment considered here, the cone or pyramid shape of the deflector 19 is substantially centered on the axis Z-Z. When the protection device 10 is installed in the scrubber 1 , the deflector 19 is arranged below and vertically at a distance from the apical body 1 1 such that the truncated apex of the cone or pyramid shape of the deflector 19 faces downwards and the respective ends 16 of the bottom edges 15 of the channels 14 are vertically spaced away from the deflector 19 by a distance d equal to at least 85 mm. The deflector 19 makes it possible to reduce the head loss caused by the protection device 10 on the fumes F leaving the duct 2.

Lastly, various developments and other variants to the protection device 10 considered thus far may be considered. As an example, rather than being strictly triangular, the cross-section of the channels 14 may be only substantially triangular, as long as it defines, for each channel, a lower bottom edge, on which lateral slopes of the channel concentrate the water collected by this channel, and along which the water flows until reaching the periphery 1 1 B of the apical body 1 1 of the protection device 10 before leaving the latter. The bottom and top edges can thus be more or less blunt.

Claims

1 A protection device (10) for protecting fume intake into a scrubber,

said protection device being suitable for being arranged inside a scrubber (1 ) and including an apical body (1 1 ) which, when the protection device is installed in the scrubber, is placed above a downstream mouth of a vertical duct (2) for admitting fumes (F) into the scrubber, so as to protect the duct against the introduction of water while allowing the fumes leaving the duct to pass,

characterized in that an upper face (12) of the apical body (1 1 ), which faces upwards when the protection device (10) is installed in the scrubber, is provided with channels (14) for collecting water, which each extend lengthwise from a central region (1 1 A) of the apical body, around which the channels are distributed, to a periphery (1 1 B) of the apical body, which is completely occupied by the channels,

in that each channel (14) has, over its entire length, a cross-section that is substantially triangular and whereof one of the apices, which faces downwards when the protection device is installed in the scrubber, defines a bottom edge (15) along the channel,

and in that the respective bottom edges (15) of the channels (14) rest on a conical surface, the apical angle of which is between 90 and 170° and which converges upwards when the protection device is installed in the scrubber.

2.- The protection device according to claim 1 , wherein the apical angle of said conical surface is between 100 and 140°.

3.- The protection device according to one of claims 1 or 2, wherein six to eighteen channels (14), preferably six to twelve channels (14), are provided.

4.- The protection device according to any one of the preceding claims, wherein the substantially triangular cross-section of each channel (14) has, at its apex located on the bottom edge (15) of this channel, an angle (a) of between 30 and 120°, preferably between 60 and 90°.

5.- The protection device according to any one of the preceding claims, wherein the substantially triangular cross-section and the depth of each channel (14) increase when one travels the channel from the central region (1 1 A) to the periphery (1 1 B) of the apical body (1 1 ).

6.- The protection device according to any one of the preceding claims, wherein the bottom edges (15) of the channels (14) have, at the periphery (1 1 B) of the apical body (1 1 ), respective ends (16) that are located on a circle (C16), which is substantially concentric to the duct (2) and the diameter of which is between 1 .1 and 2 times the inner diameter of the duct, preferably between 1 .25 and 1 .65 the inner diameter of the duct.

7.- The protection device according to any one of the preceding claims, wherein the protection device (10) further includes a collar (18) that is fastened to the apical body (1 1 ) so as, when the protection device is installed in the scrubber, to be arranged below the apical body (1 1 ), while extending substantially vertically from the apical body over a height (h) of between 15 and 75 mm and while being completely located inside the vertical projection of the apical body.

8.- The protection device according to claims 6 and 7 considered together, wherein the collar (18) has an outer diameter that is between 0.86 and 0.985 times the diameter of said circle (C16).

9.- The protection device according to any one of the preceding claims, wherein the protection device (10) further includes a deflector (19) having a cone or pyramid shape with four, six or eight sides, which, at its apex, is truncated and has a through opening having a diameter equivalent to at least 100 mm, this deflector being, when the protection device is installed in the scrubber, arranged below and vertically at a distance from the apical body (1 1 ) such that the truncated apex with the cone or pyramid shape of the deflector is turned downwards and the respective ends (16) of the bottom edges (15) at the periphery (1 1 B) of the apical body are vertically distant by at least 85 mm from the deflector.

10.- A facility for wet cleaning exhaust fumes from an engine of a marine vessel, said facility comprising:

- a scrubber (1 ) in the bottom of which a vertical duct (2) for the intake of fumes (F) in the scrubber emerges,

- a protection device (10), which is according to any one of the preceding claims and which is arranged inside the scrubber (1 ), the apical body (1 1 ) of this protection device being placed above a downstream mouth of the duct (2) so as to protect the duct against the introduction of water while allowing the fumes (F) leaving the duct to pass, and - a distribution device (3), which is arranged inside the scrubber (1 ) above the protection device (10), and which is suitable for distributing water in the form of a rain (P) falling downward in the scrubber (1 ).