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Title:
PANEL DEVICE FOR DESALINAZING WATER AND COLLECTING SALTS AND/OR DEBRIS, PLANT, AND OPERATING PROCESS THEREOF
Document Type and Number:
WIPO Patent Application WO/2022/162522
Kind Code:
A1
Abstract:
The present invention discloses a panel device for desalinating water and collecting salts and/or debris, comprising: at least one flat serpentine pipe placed on a panel exposed to the sun; at least one parabolic and/or hemicylindrical mirror coaxially arranged around the rectilinear portions of at least one serpentine pipe; at least one container for accumulating the precipitated and gathered brine and/or salts; characterized in that said serpentine pipe is configured in such a way as to comprise in its internal compartment a means for the horizontal transportation of the precipitated salt crystals and/or debris internally to said serpentine pipe and conveying them toward said container placed under said panel, said serpentine pipe and said container being in communication with each other by way of openings. The present invention also discloses a plant for desalinating water comprising one or more panel devices according to this invention and a process for operating the panel device and the plant.

Inventors:
CAPRIO FRANCESCO
Application Number:
PCT/IB2022/050626
Publication Date:
August 04, 2022
Filing Date:
January 25, 2022
Export Citation:
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Assignee:
SMARTGRUBS SRLU (IT)
International Classes:
B01D1/00; B01D1/08; B01D1/22; B01D1/24; B01D3/02; C02F1/14; C02F1/18; F22B1/00; C02F103/08
Attorney, Agent or Firm:
DE TULLIO, Michele Elio (IT)
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Claims:
CLAIMS

1. A panel device (1 ) for desalinating water and collecting salts and/or debris, comprising: at least one flat serpentine pipe_(10) placed on a panel (20) exposed to the sun; at least one parabolic mirror (30) coaxially arranged around the rectilinear portions (10.1 ) of at least one serpentine pipe (10); a container (40) for accumulating the precipitated and collected brine and/or salts; characterized in that said serpentine pipe (10) is configured in such a way as to comprise, in its internal compartment (10.2), a horizontal transport mean (50) for transporting the precipitated salt crystals and/or debris internally to said serpentine pipe (10) conveying them toward said container (40) placed under said panel (20), said serpentine pipe (10) and said container (40) being in communication with each other by way of openings (10.6; 40.1 ).

2. The panel device (1 ) according to claim 1 , characterized in that said horizontal transport mean (50) for transporting the accumulated salt crystals and/or debris internally to said serpentine pipe (10) is provided with a plurality of sequentially arranged hydraulic bulkheads anchored to a mean used for transporting them.

3. The panel device (1 ) according to claims 1 and 2, characterized in that said mean for transporting is a chain (50.1 ) and said hydraulic bulkheads (50.2) are circular bulkheads, both of them being moved by way of a towing head and a crown gear (50.3).

4. The panel device (1 ) according to anyone of the preceding claims, characterized in that said serpentine pipe (10) is continuous in a single panel, by passing on the lower surface of the panel with the portion (10.8) and allowing water recirculation in several successive cycles in the panel device (1 ).

5. The panel device (1 ) according to anyone of the preceding claims, characterized in that the end (10.9) of the pipe (10) is provided with an opening (10.6) on the lower surface, comprising a valve (10.5) for discharging the salts and/or debris into a container (40) and an outlet valve (10.4) for transferring the high-pressure steam accumulated internally thereto to a pipe element (100).

6. The panel device (1 ) according to anyone of the preceding claims, characterized in that said container (40) is provided with a filling level sensor and with a valve for opening the lower surface (40.2) of said container.

7. The panel device (1 ) according to anyone of the preceding claims, characterized in that said mirror (30) is a hemi-cylindrical mirror.

8. The panel device (1 ) according to anyone of the preceding claims, characterized in that it is configurated to be modular.

9. The panel device (1 ) according to claim 8 characterized in that said pipe element (100) is configured for being connectable to a senpentine pipe (10) of a successive panel device (1 ) connected in series thereto.

10. A water desalination plant (500) comprising one or more panel devices (1 ) according to claims 1 to 9, at least one steam turbine (200), and at least one condensing heat exchanger (300), characterized in that said one or more panel devices (1 ) are configured for circulating the water to be treated through several cycles in one panel only or through several panels connected to each other and, at the end of the desalination cycles, for inject the steam, at a predetermined tension and a predetermined temperature, into said pipe element (100) jointly with and/or alternatively connected to at least one condensing heat exchanger (200) and/or to at least one steam turbine (300), by means of said at least one valve (10.4) of said serpentine pipe (10).

11. A process for operating the device and plant according to claims 1 to 10, comprising the following steps: a. filling said serpentine pipe (10) of the panel device (1 ) with water containing salts and/or debris by way of an inlet valve (10.3); b. heating said serpentine pipe (10) by way of parabolic and/or hemicylindrical mirrors (30) exposed to the sun; c. increasing steam tension internally to said serpentine pipe (10); d. forming an oversaturated solution of salts; e. precipitating the salts and debris contained internally to said oversaturated solution; f. conveying the precipitated and/or suspended salts and/or debris by means of said horizontal transport mean (50); g. recirculating the water to be treated present in the serpentine pipe (10) up to reaching the required temperature and steam pressure values or passage into

17 another panel device connected thereto.

12. The process according to claim 11 , comprising the following further steps: h. conveying the steam into the pipe element (100) for the outflow by means of the outlet valve (10.4), after reaching predetermined temperature and pressure values; i. discharging the accumulated salts and/or debris into said container (40) by means of a discharge valve (10.5); j. conveying into said serpentine pipe (10) of new water to be treated inside said panel device (1 ) by way of an opening valve (10.3).

13. The process according to claim 12, comprising the following further steps: k. conveying stem into the pipe element (100) and therefrom into a condensing heat exchanger (200) of the plant (500) by means of the outlet valve (10.4), after reaching predetermined temperature and steam pressure values suitable for condensing the stem produced; l. producing desalinated water.

14. The process according to the previous claims 1 1 thru 13, comprising the following further steps: m. conveying steam into the pipe element (100) and therefrom to a steam turbine (300) of the plant (500) by means of the outlet valve (10.4) after reaching predetermined temperature and steam pressure values suitable for producing electric and/or mechanical energy; n. sending steam exiting from the turbine (300) to a heat exchanger (200) for

18 condensation; o. producing desalinized water. wherein said steps m) and n) of the process take place jointly with and/or alternatively to steps k) and I) of the process.

Description:
PANEL DEVICE FOR DESALINAZING WATER AND COLLECTING SALTS AND/OR

DEBRIS, PLANT, AND OPERATING PROCESS THEREOF

DESCRIPTION

The present invention relates to the field of devices and apparatuses for desalinating waters; in particular, the present invention relates to a device for desalinating waters and simultaneously making it possible to precipitate and subsequently store the salts contained therein.

Status of the art

Numerous devices and numerous patent documents are present in the present status of the art which describe devices and apparatuses for desalinating water.

Document W02020190995A1 entitled “Desalination System’’ discloses a system and a method for desalinating and heating water, based on the use solar energy; in a particular embodiment of this invention, salt water feeds a pre-heating system 1003. The pre-heating system 1003 is a hose which contains salt water and holding heat. Heat is provided via solar energy concentration systems including, amongst others, lenses or a linear parabolic mirror. The system provides a plurality of desalinating units. Document KR101131092B1 entitled “Evaporative Desalination Apparatus Of Sea Water Using Heatpipe” discloses a solar heat evaporative sea water desalination apparatus, which uses a heat pipe including a thermal accumulation tank (10), a heat pipe (20), and a desalinator (60). The heat duct is connected to the thermal accumulator and makes hot water circulate inside the thermal accumulator.

Document US2011001 1802A1 entitled “Systems And Methods For Simultaneously Generating Energy And Treating Water” discloses a system that allows to cool a concentrated photovoltaic cell while simultaneously treating water, for example sea water desalination. A concentrated photovoltaic panel converts solar energy into electric energy. The recirculating water, for example sea water or regenerated water, at a temperature comprised in an optimized range of values, flows through the photovoltaic panel to cool the photovoltaic solar cells down. The recirculating water is heated by the photovoltaic panel and is subsequently conveyed to a water treatment unit, for example a heat exchanger or a water dissipator. The water treatment unit is either a high temperature reverse osmosis (RO) unit, a vacuum evaporator, or a bacterial water treatment plant. The treated water stream enters the heat exchanger/desalinator unit. The heat associated with the heated recirculating water is used to treat the colder water.

Document US10654726B2 entitled “Solar Desalinator” discloses a solar desalinator which purifies water and renders it drinkable by using a cylindrical solar collector, a parabolic mirror featuring a concave shape, and a condenser. The solar collector is positioned inside the parabolic mirror featuring a depressed shape, and the parabolic mirror concentrates the sun rays in the solar collector, heats water, and converts water into vapor.

Document RU2668249C1 entitled “Solar Desalinator With Parabolic-Cylinder Reflectors” discloses a device used for distilling mineralized, polluted, or sea waters by using solar energy only to heat water. The solar desalinator comprises a solar concentrator mounted on parabolic cylindrical reflectors provided with brackets with holes on which the evaporating pipes positioned in the reflector focuses are located.

It results from this analysis of the present state of the art that a plurality of devices are known for desalinating salt waters, the object of which is that of separating the salts dissolved in water from water made drinkable; many of these devices use sun light to heat pipe systems internally to which salt water circulates.

A need results from this analysis of the present state of the art for providing a device whereby the technical problem of water desalination is solved, while providing an effective and continuous separation and conveyance and accumulation of the precipitated salts and debris present in waters.

The device according to this invention mainly aims at an effective and continuous gathering of the salts precipitated inside the device and simultaneously allows for an effective conveyance of the produced steam to valves and a pipe network, in order for it to be expelled; this allows to accumulate the gathered salts internally to an appropriate container, while also allowing for an effective desalination of salt and/or dirty waters.

Brief description of the invention

An object of the present invention is to provide a modular device for continuously desalinating waters by means of solar concentrators and chain conveyors; this device is a modular device in which every individual element will be here referred to as a panel device.

The device according to this invention is used for desalinating both salt waters and waste waters and/or dirty waters.

This modular desalination system is characterized in that it comprises: a pipe which conveys the stream of water to be desalinized, a plurality of parabolic mirrors, which concentrate the solar radiation, and a system of horizontal chain conveyors, which are used to prevent sediments and precipitates from accumulating in the pipe system and allow to convey and gather the precipitated salts in an appropriate container. The pipe is a flat serpentine pipe implemented in such a way as to maximize the heating of the water conveyed internally thereto. A number of parabolic and/or hemicylindrical mirrors are present, coaxial to the pipe, suitable for concentrating the solar radiation in the pipe system itself and/or on the surface thereof.

Conveniently are the dimensions and the concavity of the parabola, which describes the profile/cross section of said mirrors, selected consistently with the housing of said pipe in terms of dimensions, positioning, and fixture, in order for the centre of the pipe itself to coincide with the focus of the above-mentioned parabolic mirror.

Thanks to the geometry described here above, the heat produced by solar radiation heats the water circulating through the pipe system, up to a total vaporization of the circulating water itself, thus causing the salts dissolved therein to precipitate. Under appropriate conditions, the heat produced by solar radiation can result in an overheating and overpressure of the water vapor itself.

Horizontal chain conveyors are present internally to said pipe system, comprising sequences of circular, hydraulic locks and/or bulkheads, which slide internally to said pipe system, being driven by a chain or by another driving mechanism.

Said horizontal chain conveyors perform a number of functions, which consist of: fostering water flow internally to said pipe system and removing/preventing accumulations/deposits and/or making it possible an effective gathering of the precipitated salts and other impurities initially present in the water fed to said panel and, finally, allowing for an effective conveyance of the steam accumulated inside the pipe system.

The panel device comprises, along the development of the pipe, and preferably in its terminal part, a container, vertically accommodated under the plane where the serpentine pipe is located, perpendicularly to the axis of development of the pipe system, to gather and accumulate the salts deposited along the pipe and removed by the sequence of bulkheads, up to the mouth of said store, where they are deposited by gravity.

Said store/container is periodically emptied, following a manual and/or automatic external drive/control of a set of valves, input to and output from said container, by effect of gravity and/or differences of pressure with the external environment.

Said pipe system also comprises an outlet port, be it equipped or not equipped with valves, which prevents any return flows, positioned at the end of the development of said pipe system. Said outlet can conveniently be connected to a second panel and/or to the recirculation of the water to be treated in the same panel, and/or to further process stages, if any, like those described above.

The invention also comprises a desalination plant which includes one or more panels according to this invention, connected to at least one condensation heat exchanger and/or to a turbine.

A further process stage, output from one single panel or from a plurality of panels cascaded to each other, possibly comprises a turbine for generating electric energy, driven by the passage of the steam produced by the panels interconnected to each other.

Alternatively to said turbine and/or downstream it, a condensing heat exchanger can be adopted, which condensate the vapours themselves, and recovers the heat associated with these vapours and/or hot liquids output from the above-described system.

Brief description of the figures

Other advantages, characteristics, and modes of use of the device according to the present invention will be apparent from the following detailed description of one embodiment thereof, which is presented for explanatory, non-limitative purposes only, and with a special reference to the attached figures, wherein: figure 1 - a side, top axonometric view of a panel device 1 ; figure 2 - a top axonometric view of a detail of figure 1 , namely the internal compartment of the serpentine pipe, with the horizontal transport means inside, wherein the wall of the pipe has been removed in order to make the horizontal transport means present internally to the pipe visible; figure 3 - a view of a detail of figure 2, wherein the wall of the pipe 10 has been removed to make the coaxial chain with the centre of the pipe and the circular hydraulic bulkheads visible; figure 4 - a view of the upper surfaces of the device placed on a panel; figure 5 - a view of the lower surface of the device, where the rectilinear section of the pipe 10 passing on the lower surface of the panel or flat support 20 is visible; figure 6 - a side view of the longer side of the device; figure 7 - a side view of the shorter side of the device; figure 8 - a side, top axonometric view of one embodiment of the panel device 1 , where the opening and closing valves of the pipe which are ball valves, are visible; figure 9 - a schematic view of a plant 500 according to the invention.

Leqenda

1. Desalination panel device;

10. Flat serpentine pipe;

10.1 rectilinear section of said pipe 10;

10.2 internal compartment of said pipe 10;

10.3 water inlet valve for feeding water into the pipe 10;

10.4 outlet valve for feeding steam and/or liquid into the pipe 10;

10.5 valve for discharging salts and/or debris into a container 40; 10.6 opening of the pipe 10 placed below in correspondence with a container 40;

10.7 ball valves for device opening and closing ;

10.8 rectilinear section of said pipe 10 passing on the lower surface of the panel or flat support 20;

10.9 end of said pipe 10 in connection with a container 40;

20. Panel or flat support on which said serpentine pipe is anchored;

30. Mirrors;

40. Salt and/or brine accumulation container;

40.1 opening of container 40;

40.2 lower surface of container 40;

50. Horizontal transport mean;

50.1 chain;

50.2 circular bulkhead;

50.3 towing head and a crown gear;

100. Pipe element for steam conveyance;

200. Condensing heat exchanger;

300. Steam turbine;

500. Desalination plant.

Detailed description of the invention

The present invention discloses a panel device 1 for desalinating salt waters, in particular sea water, but also waste waters and dirty waters.

The present invention provides a modular device and system for continuously desalinating waters to be treated by way of solar concentrators and chain conveyors.

One preferred embodiment of the present invention comprises a panel device 1 used for desalinating water and collecting salts and/or debris, comprising at least one flat serpentine pipe 10 placed on a panel 20 exposed to the sun, at least one parabolic mirror 30 coaxially placed around a rectilinear portion 10.1 of at least one serpentine pipe 10 and at least one container 40 for accumulating the precipitated and gathered brine and/or salts.

Said panel 20 is a flat support on which the sepentine pipe is anchored.

In one preferred embodiment of this invention, said mirrors 30 are hemicylindrical.

This device is also characterized in that said serpentine pipe 10 is configured in such a way as to comprise, in an internal compartment 10.2, a means 50 for the horizontal transportation of the precipitated salt crystals and/or debris internally to said serpentine pipe 10 and their conveyance to said container 40 placed under said panel or flat support 20, in a position perpendicular to the axis of development of the serpentine pipe, the liquid internally thereto, and the horizontal transport means; finally, said serpentine pipe 10 and said container 40 being in communication to each other by way of their respective openings 10.6; 40.1 .

Said horizontal transport means 50 used for transporting the salt crystals and/or debris accumulated internally to said serpentine pipe 10 is provided with a plurality of sequentially arranged hydraulic bulkheads anchored to a means used for moving them. The horizontal transport means 50 used for transporting the salt crystals precipitated internally to said serpentine pipe 10 comprises a chain 50.1 , coaxially arranged internally to the serpentine pipe 10 and provided with a plurality of circular bulkhead 50.2 equally spaced from each other.

Said handling means is a chain 50.1 and said hydraulic bulkheads 50.2 are circular bulkheads, both being moved by way of a towing head and a crown gear 50.3.

These bulkheads are preferably circular hydraulic bulkheads configured in such a way as to fit the diameter of said pipe 10, so as to lick the inner surface of said pipe 10 and displace the salts and/or sediments that deposit on the bottom. These bulkheads also contribute to conveying steam toward the end 10.9 of the pipe 10.

Also, said horizontal transport means 50 is provided with a towing head and a crown gear 50.3 for moving said chain 50.1 .

Said crown gear will be configured in such a way as to have a number of housings suitable for accommodating the hydraulic bulkheads 50.2 and driving them in such a way as to allow the movement of the chain and of the bulkheads.

These bulkheads are configured for transporting the precipitated salts and debris toward the container 40 in a fully innovative manner, thus making their collecting simpler, and also fostering the flow of vapor toward an outlet port.

The serpentine pipe 10 described in the present invention is a closed-circuit serpentine pipe arranged on a plane; as a matter of fact, the pipe 10 is continuous in a single panel 1 and is configured to subsequently pass onto the lower surface of the panel as a rectilinear pipe, after forming said serpentine on the upper surface of the panel, and to subsequently continue on the upper surface; this implies that, in the moment when all valves of the pipe 10 are closed, water recirculation can take place in several successive cycles, up to reaching predetermined steam pressure and temperature values, and up to accumulating a given quantity of salts and/or debris.

In a further embodiment, the device 1 is modular and the serpentine pipe 10 is connected to another pipe, thus making it possible to continue the desalination cycle in another panel.

In this further embodiment, the pipe element 100 is configured for being connectable to a serpentine pipe 10 of a subsequent panel device 1 , so as to implement a serial interconnection of several panels. The serpentine pipe 10 will be preferably made from a material suitable for absorbing the solar radiation and for a subsequent conversion into heat, i.e. a material that is transparent to the solar radiation itself.

After being displaced over the development of the pipe 10, the salts and/or sediments are conveyed up to the container 40 where, below said pipe 10, there will be an opening configured in such a way as to allow the accumulated salts and/or sediments and/or debris to drop by gravity; the end 10.9 of the pipe 10 is provided with an opening 10.6 on the lower surface, comprising a valve 10.5 for unloading salts and/or debris into a container 40, and an outlet valve 10.4 for transferring the high-pressure steam accumulated internally thereto to a pipe element 100.

Said container 40 is in communication with said serpentine pipe 10 through an opening 40.1 placed in correspondence with the opening 10.6 of the end 10.9 of the serpentine pipe 10.

Said opening 10.6 through which said serpentine pipe 10 communicates with the container 40 is provided with a valve used to control the opening and closing of the container and with a sensor used to detect the filling level of the pipe close to the container 40.

In one preferred embodiment, the container 40 is a cylindrical container placed under said panel or flat support 20, close to the end 10.9 of said serpentine pipe, in a position perpendicular to the axis of development of the serpentine pipe.

The container 40 is in turn provided with a lower valve controlling the opening of the lower surface 40.2 of said container for the final discharging of the gathered salts and/or debris; in the case of brine, i.e. in the case of sea water treatment, this brine might be unloaded into the sea at the end of a recycle thereof.

In one preferred embodiment, said mirrors 30 are hemicylindrical. As already said before, the serpentine pipe 10 is connectable to a pipe element 100 to supply it with the vapor produced upon heating the water contained in the pipe itself, if the vapor reached the desired pressure and temperature values, or, if several panels are connected to each other and the fluid internally present did not vaporize yet, this pipe element 100 will allow water to flow into another panel.

Close to the pipe element 100, the serpentine pipe 10 is provided with a valve 10.4 to make it possible for the steam accumulated internally thereto to go out.

At the output from a single device or from a set of devices 1 forming a modular system of said device 1 , it is possible to install a turbine for generating electric energy, operated by the passage of the steam produced by the device.

Alternatively to said turbine and/or downstream it, a condensing heat exchanger can be adopted for condensing the vapours themselves and recovering the heat associated with these vapours and/or hot liquids output from the above-described system and for recovering the desalinized water.

The device according to this invention is modular and is configured for being connected to another device identical thereto.

The present invention also discloses a plant 500 for desalinating water, comprising one or more panel devices 1 , at least one steam turbine 200, and at least one condensing heat exchanger 300, characterized in that said one or more panel devices 1 are configured for processing the water to be treated in several cycles, in one panel only or thought several panels and, at the end of the desalinization cycles, feeding steam, at pre-determined pressure and temperature values, into said pipe element 100 jointly and/or alternatively connected to at least one condensing heat exchanger 200 and/or a steam turbine 300, via said at least one valve 10.4 of said serpentine pipe 10.

The present invention also discloses a desalination process of the panel device and of the plant, comprising one or more panel devices. The operating process comprises one or more process cycles on the water to be treated, via one and the same panel device 1 , or a process cycle on the water to be treated via several panels connected in series to each other; at the end of this desalination process, there will be a water deprived of salts and debris present internally thereto, which will be precipitated or simply separated, and a subsequent passage of all the water present internally to the pipe system in the vapor status, up to reaching a predetermined steam pressure and a predetermined temperature.

At this point, the accumulated steam can be conveyed to the pipe element 100 for producing desalinized water.

Therefore, the steam can be sent to gathering or remodulation basins or to a heat exchanger for (latent) heat recovery purposes.

In the preferred embodiment of the plant, the steam is sent to a heat exchanger, which is a condensing heat exchanger; thanks to the produced vapor being condensed, desalinized water will be produced.

Therefore, in this version of the invention, the energy associated with the high-pressure steam can be converted, first into electric energy and/or mechanical energy; then the steam is sent to a turbine for producing electric and/or mechanical energy, for being subsequently sent to a condenser.

The present invention also discloses a process for operating the device and plant, including the following steps: a. filling said serpentine pipe 10 of the panel device 1 with water containing salts and/or debris by way of an inlet valve 10.3; b. heating said serpentine pipe 10 by way of parabolic and/or hemicylindrical mirrors 30 exposed to the sun; c. increasing the steam pressure internally to said serpentine pipe 10; d. forming an oversaturated solution of salts; e. precipitating the salts and debris contained internally to said oversaturated solution; f. displacing the precipitated and/or suspended salts and/or debris by way of said horizontal transport mean 50; g. recirculating the water present in the serpentine pipe 10 up to reaching the necessary temperature and pressure values.

Said process comprises the following final steps: h. conveying steam in the pipe element 100 for making it go out through the outlet valve 10.4, after reaching predetermined temperature and pressure values; i. discharging the accumulated salts and/or debris into said container 40 by means of a discharge valve 10.5; j. conveying new water to be treated into said serpentine pipe (10) internally to said panel device (1 ) by way of an opening valve 10.3.

In these operating steps, the final products of the panel device, i.e. a high-pressure steam and the gathered salts and/or debris, are obtained.

In order to get desalinized water, the operating process of the plant according to this invention comprises the following further steps: k. sending steam to a heat exchanger 200 of the plant 500 by way of the outlet valve 10.4, after reaching predetermined temperature and pressure values suitable for condensing the produced steam; l. producing desalinized water; wherein the steam is sent to a steam heat exchanger for obtaining desalinized water.

Before entering a condensing heat exchanger, the high pressure and temperature steam can be sent to a steam turbine, in order to transform its energy into an electric and/or mechanical energy; therefore, the process might comprise the following steps: m. conveying steam to a steam turbine 300 of the plant 500 via the valve 10.4. after reaching predetermined temperature and pressure values as necessary for producing electric and/or mechanical energy; n. sending steam output from the turbine 300 to a heat exchanger 200 for condensation; o. producing desalinized water.

In this case, steps m) and n) of the process take place jointly with and/or alternatively to steps k) and I) of the process; or steam might be simultaneously sent to a heat exchanger and to a turbine.

The scope of the invention is susceptible of numerous modifications and variants, all falling within the inventive concept set forth in the attached claims.

All details might be replaced by other technically equivalent elements, depending on the actual requirements, without leaving the scope of protection of the present invention. Even though the scope has been described with a special reference to the attached figures, the reference numerals used in this description and in the claims are used for improving the understanding of the invention and do not entail any limitation to the claimed scope of protection.