WO2015015465A1

WO2015015465A1 - Plant and method for the production of an emulsion of water and hydrocarbons

Info

Publication number: WO2015015465A1
Application number: PCT/IB2014/063617
Authority: WO
Inventors: Sandro Toffoletto
Original assignee: Nanotechlab S.A.
Priority date: 2013-08-02
Filing date: 2014-08-01
Publication date: 2015-02-05
Also published as: EP2832433A1

Abstract

A plant and associated method for producing a water and hydrocarbon emuision wherein a water supply circuit (2) and a hydrocarbon supply circuit (3) distribute water and hydrocarbon in a mixing circuit (4); the mixing circuit (4) comprises at least two tanks (16a, 16b) separated from each other and a pipe (13) connecting the tanks (16a, 16b) in order to transfer the water and hydrocarbon mixture from one tank to the other a series of times until obtaining an emulsion.

Description

PLANT AND METHOD FOR THE PRODUCTION OF AN EMULSION OF WATER AND HYDROCARBONS

The present invention relates to a plant and a method for producing a water and hydrocarbon emulsion.

In particular, the emulsion produced by the plant and associated method of the present invention is of the type comprising water and a hydrocarbon, such as, for example, diese!, biodiesei, dense fuel oil and the like.

Emulsions of this type are mostly used to fuel internal combustion engines, in particular diesel engines, both of vehicles or ships and stationary electric power plants, or burners in turbines or boilers.

The water and hydrocarbon emulsion can be advantageously used in internal combustion engines, since it can reduce the harmful emissions in exhaust gases due to the low level of unburned substances (NOx), smokiness and particulate matter (P ). At the same time, water and hydrocarbon emulsions enable the efficiency of the fuel and average lifespan of an engine to be increased, with consequent cost savings.

In particular, water/hydrocarbon emulsions consist of stabilized water-in- hydrocarbon suspensions obtained by means of a mechanical action of cavitation and the use of surfactant substances which prevent the separation of the two insoluble liquid phases for a given period of time. As is well known, emulsions are produced in plants equipped with specific mixing circuits capable of atomizing the particles of water and hydrocarbons and subsequently distributing the emulsion to a user, e.g. an engine or a storage tank.

Emulsion plants are generally endowed with a mixing circuit having a tank into which the water and hydrocarbon are dispensed, along with an additive used as a stabilizer and antioxidant and to improve the combustion of the emulsion.

The mixture contained in the tank is then made to circulate along a pipe and through a mixer, generally consisting of a static cavitator, in order to create the emulsion of the mixture, which is recirculated from the tank to the mixer for a preset number of times corresponding to a cycle necessary to obtain a stable emulsion having adequate physical characteristics.

The quality of the mixture obtained, and in particular its stability, depend both on the final size of the particles and the homogeneity of the distribution of the particles in the mixture. In particular, the emulsion's stability increases with decreasing particle sizes and an increasingly uniform distribution of the water, hydrocarbon and additive particles.

For this reason, the emulsion cycle entails a series of passages of the mixture from the tank to mixer, until the particles have adequate dimensions and a homogeneous distribution.

At the end of the emulsion cycle, the mixture in the form of an emulsion of water, hydrocarbon and additive is distributed to the storage tank in order then to be supplied to the user.

However, plants of this type have several drawbacks and are susceptible of improvement from the standpoint of the stability of the emulsion obtained.

It should be noted, in fact, that some emulsion cycles are unable to distribute the water and hydrocarbon particles homogeneously, resulting in the formation of areas of stagnation in the mixture.

This drawback is due to the fact that, during the emulsion cycle, the mixing tank is not completely emptied and this determines the formation of areas in which the mixture remains in the tank and is not withdrawn so as to be passed through the mixer.

Consequently, areas of stagnation form in the mixture and, not being duly mixed, they are not correctly emulsified with adequate parameters in terms of homogeneity and particle size.

Moreover, introducing the water, hydrocarbon and additive directly into the tank in itself determines a difficulty of mixing, given the difference in the weight and viscosity of the three liquids, which tend to become stratified. Consequently, in order to obtain a correct emulsion, the cycle of recirculating from the tank to the mixer must be repeated multiple times, with resulting disadvantages in terms of production times and hence the costs of producing the emulsion.

Moreover, keeping the mixture in the storage tank or mixing tank for a given period will favour the re-aggregation of the particles and thus the formation of water "bubbles". In this situation, excessively large liquid particles damage the quality of the mixture, which during use can create major malfunctions in the internal combustion engine.

In this context, the technical task of the present invention is to provide a plant and a method for producing a water and hydrocarbon emulsion which is capable of achieving a stable emulsion in an efficient manner.

In particular, it is an object of the present invention to provide a plant and a method capable of emulsifying water and a hydrocarbon very quickly to obtain a mixture that is stable over time.

A further object of the present invention is to provide a plant and a method for producing a water and hydrocarbon emulsion that is versatile in relation to the various application requirements and structurally simple and has moderate costs.

These and other objects are substantially achieved by a plant and a method for producing a water and hydrocarbon emulsion according to what is described in one or more of the appended claims. The dependent claims correspond to possible embodiments of the invention.

Additional features and advantages will be more clearly apparent from the detailed description of a preferred but non-exclusive embodiment of a plant and of a method for producing a water and hydrocarbon emulsion according to the present invention.

This description is provided with reference to figure 1 , intended purely as a non-limiting example, in which there is shown a diagram of the plant for producing the water and hydrocarbon emulsion according to the present invention.

With reference to figure 1 , 1 indicates overall a plant for producing a water and hydrocarbon emulsion.

The plant 1 comprises a water supply circuit 2 and a hydrocarbon supply circuit 3, both designed to supply the water and hydrocarbon to a mixing circuit 4.

In particular, the water supply circuit 2 comprises a tank 5, inside which the water to be introduced into the mixing circuit 4 is stored. The tank 5 is preferably endowed with a heating element 6 for heating the water, and a level sensor 7 for monitoring the amount of water contained in the tank. Positioned upstream of the tank 5 there is a reverse osmosis unit 8, of a known type and thus not further described or illustrated in detail, serving to purify the water that is distributed to the tank 5.

The reverse osmosis unit 8 is connected to a water distribution system 9 and purifies the incoming water in order then to supply it to the tank 5 through a pipe 10.

The water supply circuit 2 further comprises a water distribution pipe 11 , disposed downstream of the tank 5 so as to supply the water from the tank 5 to the mixing circuit 4.

Positioned along the distribution pipe 11 there is a pump 12 for drawing a predefined amount of purified water from the tank 5 and dispensing it into a connecting pipe 13 belonging to the aforesaid mixing circuit 4.

The hydrocarbon supply circuit 3 comprises a pair of pipes 14a, 14b, each of which is connected to a system 15 for distributing the hydrocarbon. In this manner, each pipe 14a, 14b will distribute the hydrocarbon from the distribution system 15 to the inside of a respective tank 16a, 16b belonging to the mixing circuit 4, as will be better described below.

Positioned in the distribution system 15 there is preferably a hydrocarbon feed device 7 (not described in detail, being of a known type) designed to distribute a predefined amount of the hydrocarbon to one of the pipes 14a, 14b.

The plant 1 further comprises a circuit 18 for supplying at least one additive and associated with the inlet of each tank 16a, 16b in order to feed the additive directly into the tanks. The additive generally consists of substances which have a stabilizing, bonding, antioxidant function and are suitable for improving the combustion of the emulsion obtained in the plant

1.

in particular, the additive supply circuit 18 comprises a tank 19, disposed inside which there is preferably a heating element 20 for heating the additive contained in the tank 19 itself. Moreover, the tank 19 is preferably equipped with a level sensor 21 capable of monitoring the amount of additive present in the tank 19.

The additive supply circuit 18 comprises a feed pipe 22 which distributes the additive from a respective holding receptacle 23 to the aforesaid tank 19.

Moreover, the additive supply circuit 18 comprises a pipe 24 for distributing the additive, disposed downstream of the tank 19 in order to feed the additive from the tank 19 (in which it is prepared for mixing with the water and the hydrocarbon) to the mixing circuit 4.

Positioned along the distribution pipe 24 there is a pump 25 for withdrawing a predefined amount of additive from the tank 19 and dispensing it into one of the tanks 16a, 16b. For this purpose, it should be noted that the additive distribution pipe 24, in the terminal part thereof, splits off into two branches, each of which is connected to a respective tank 16a, 16b. The pump 25 and suitable valve systems (not described or illustrated, being per se of a known type) select the branch and hence the tank 6a, 16b into which the additive must be fed.

As mentioned above, the mixing circuit 4 comprises the two tanks 16a, 16b, appropriately separated from each other, and the connecting pipe 13 which is associated with the tanks 16a, 16b in order to transfer the emulsion from one tank 16a, 16b to the other.

in greater detail, the tanks 16a, 16b are separated from each other by means of a dividing wall 26 so as to contain the additive, water and hydrocarbon mixture in a differentiated manner. The dividing wall 26 advantageously has a vent channel 26a, which places the two tanks 16a, 16b in fluid communication to permit the passage of solely air from one tank to the other.

Each tank 16a, 16b preferably comprises a heating element 28 for heating the mixture contained in the tank itself, and a level sensor 29 for monitoring the amount of mixture contained.

Moreover, each tank 16a, 16b comprises an inlet 30 associated with a pipe 14a, 14b of the hydrocarbon supply circuit 3, and with the additive distribution pipe 24. In this manner, the hydrocarbon and the additive are fed into one of the aforesaid tanks 16a, 16b and directly mixed together inside it.

Each tank 16a, 16b further comprises an outlet 31 associated with a first inlet end 13a of the connecting pipe 3.

It should be noted in particular that the first inlet end 13a of the connecting pipe 13 is associated with the water supply circuit 2, in particular with the distribution pipe 11 , so as to permit mixing of the water and hydrocarbon leaving at least one of the aforesaid tanks 16a, 16b.

In other words, the water is introduced into the mixing circuit 4 downstream of the tanks 16a, 16b to enable the water to be mixed with the hydrocarbon and additive previously mixed together in one of the tanks

16a, 16b at the first end 13a of the connecting pipe 13.

The connecting pipe 13 comprises a second outlet end 13b opposite the first end 3a and associated with the inlet 30 of each tank 16a, 16b. It should be noted in particular that the second outlet end 13b comprises two branches 32a, 32b, each of which is associated with a respective tank

16a, 16b in order to convey the water, hydrocarbon and additive mixture into one of the tanks.

Positioned inside each tank 16a, 16b there is preferably a cavitation device 33a, 33b associated with a respective branch 32a, 32b of the second outlet end 13b. The cavitation device 33a, 33b mixes and favours the emu!sification of the mixture contained in the connecting pipe 13, which is made to recirculate from the outlet 31 of the tanks 16a, 16b to the inlet 30 of the same.

The connecting pipe 13 is advantageously provided with a static mixing member 34, such as, for example, a cavitator or turbulator (of a known type and not described in detail) capable of creating turbulence within the liquid flow of the mixture, thereby favouring its emulsion.

Advantageously, preferably downstream of the static mixing member 34, there may be positioned a dynamic mixing member 35, preferably consisting in a mixer. It should be considered that the two mixing members 34, 35 placed in series impart a very intense mixing action to the flow passing inside the connecting pipe 13, thus favouring the formation of the emulsion.

The mixture is forced through the static mixing member 34 and subsequently through the dynamic mixing member 35 by means of a pump 36 situated downstream of the first end 13a of the pipe 13. In this manner, a predefined amount of mixture leaving one of the tanks 16a, 16b is drawn in and conveyed through the first end 13a, along the pipe 13 and to the second end 3b.

Advantageously, an electronic control system 37 operatively engaged with the pump 25 of the additive supply circuit 18 and the hydrocarbon feed device 17 synchronizes the feeding of the hydrocarbon with the feeding of the additive into one of the tanks 16a, 16b. In this manner, the amount of additive and hydrocarbon introduced simultaneously into the tank is controlled so as to avoid the stratification of the two liquids inside the tank and instead mix them together.

According to a possible embodiment, the control system 37 can be suitably connected to the pump 12 of the water supply circuit 2 and to the pump 36 of the connecting pipe 13. Consequently, as control is provided over the pump 25 of the additive supply circuit 18, the hydrocarbon feed device 17, the pump 12 of the water supply circuit 2 and the pump 36 of the connecting pipe 13, the dispensing of water into the mixing circuit 4 is likewise coordinated and synchronized with the intake of the mixture contained in the tank 16a, 16b into the first end 13a of the pipe 13.

The plant 1 further comprises a circuit 38 for supplying an antifreeze liquid, comprising a receptacle 39 for containing the liquid, and a pipe 40 for feeding it to the water tank 5. The pipe 40 feeds the antifreeze directly into the tank 5 so as mix the water and antifreeze before they are introduced into the mixing circuit 4.

The plant 1 also features a transfer pipe 41 for conveying the emulsion obtained in the mixing circuit 4 to at least one user "U".

in detail, the transfer pipe 41 is associated with the connecting pipe 13 upstream of the respective second outlet end 13b in order to transfer the emulsion leaving the dynamic mixing member 35 toward the user.

Preferably, the transfer pipe 41 comprises an emulsion containing tank 42 for storing the emulsion and enabling it to be used at any time.

The tank 42 is preferably endowed with a heating element 43 for maintaining the emulsion at a given temperature and a level sensor 44 for controlling the amount of emulsion contained.

In a terminal section of the pipe 41 in proximity to the user "U", there is provided a pump 45 which feeds a predefined amount of emulsion contained in the tank 42 toward the user "U".

Advantageously, extending from the user "U" there is a return circuit 46, which permits the emulsion to be reintroduced into the plant 1.

This circuit 46 thus enables the use of an amount of the emulsion distributed to the 'user "U" which is in excess or in any case not used by the user "U".

In particular, the return circuit 46 comprises a first pipe 47 for transferring the emulsion from the user "U" to a hydraulic network external to the plant 1 , and a second pipe 48 which carries the emulsion back into the tank 42. The emulsion contained in the tank 42 can be reintroduced into the mixing circuit 4 by means of a recirculation pipe 49 which connects the tank 42 to the first inlet end 13a of the connecting pipe 13. Advantageously, if the emulsion is kept in the tank 42 for too long, it is made to recirculate in the mixing circuit 4 to maintain the emulsion stable in accordance with acceptable quality parameters in terms of particle size and homogeneity of distribution of the particles.

A bypass pipe 50 is moreover provided to connect the hydrocarbon supply circuit 3 directly with the user "U". Advantageously, depending on the user "U" (type of internal combustion engine) it is possible to selectively feed either the emulsion from the tank 42 or solely the hydrocarbon from the distribution system 5 via the bypass pipe 50.

The present invention further comprises a method for producing a water and hydrocarbon emulsion.

This method comprises the steps of feeding a hydrocarbon into the mixing circuit 4 and simultaneously feeding an additive into the mixing circuit 4. In particular, the steps of feeding the additive and feeding the hydrocarbon are carried out by distributing a predefined amount of hydrocarbon and of additive into one of the aforesaid tanks 16a, 16b. During the simultaneous feeding of the additive and hydrocarbon, preferably coordinated by the above-described control system 37, the hydrocarbon and additive are mixed inside the respective tank 16a.

Subsequently, the hydrocarbon and additive mixed together are fed into the connecting pipe 13 of the tanks 16a, 16b, which, as specified above, places the tanks 16a, 16b in fluid communication with each other. During this step, the tank which contains the hydrocarbon and additive mixture is completely emptied in order to introduce all of the mixture into the pipe 13. Simultaneously with the feeding of the hydrocarbon and additive mixture into the pipe 13, the water is fed into the mixing circuit 4 in order to mix the water with the hydrocarbon and additive.

In particular, a predefined amount of water is introduced into the connecting pipe 13 to enable a first mixing of the liquids inside the pipe 13 itself.

Advantageously, the control system 37 coordinates the simultaneous introduction of water and the hydrocarbon and additive mixture into the first inlet end 13a of the connecting pipe 13.

Subsequently, the water, hydrocarbon and additive are recirculated inside the mixing circuit 4 to obtain an emulsion.

In particular, the water, hydrocarbon and additive mixture is recirculated by transferring the mixture itself from one tank to the other a predefined number of times.

In other words, the mixture is conveyed from the first end 13a of the connecting pipe 13 to the second outlet end 13b so as to fill a first tank 16a.

The first tank 16a is thus completely emptied of the aforesaid mixture, which is conveyed back to the first inlet end 13a of the connecting pipe 13. Subsequently, the mixture is further conveyed through the connecting pipe 13 toward the second outlet end 3b thereof in order to fill the second tank 16b with the aforesaid mixture.

Then, at the end of the filling of the second tank 16b, the mixture is conveyed back into the pipe 13, thus completely emptying the second tank 16b.

This mixing cycle, in which the mixture is transferred from one tank to the other, is repeated a predefined number of times until a water, hydrocarbon and additive emulsion is obtained.

it should be noted that, during the passage of the mixture from the first end 13a of the connecting pipe 3 to the second end 3b of the pipe 13 itself, the mixture is made to pass through the static mixing member 34 and/or the dynamic mixing member 35.

Advantageously, as specified above, the mixing action of the mixing members 34, 35 favours the formation of a static emulsion having very small, evenly distributed particles.

At the end of the mixing cycle, the emulsion is withdrawn upstream of the second end 13b of the connecting pipe 13 and conveyed toward the user "U" via the transfer pipe 41. Advantageously, the plant 1 and the method associated therewith are capable of obtaining a stable emulsion having very small, evenly distributed particles.

This advantage is derived from the action of transferring the mixture from one tank to the other for a defined number of times, which prevents the formation of areas of stagnation in the mixture.

In other words, all of the mixture contained in the mixing circuit 4 is made to circulate along the pipe 13 and into the respective tanks 16a, 6b.

Consequently, the particles are suitably mixed, giving rise to a stable, homogeneous emulsion.

Moreover, the mixing of the water, hydrocarbon and additive directly inside the pipe 13 favours the mixing of the liquids, preventing the stratification thereof. Therefore, the emulsion is obtained in a simpler manner and in a much shorter time.

It should also be considered that the plant 1 is structurally simple and very versatile, since it is capable of recovering the excess emulsion and can be adapted to any type of user "U" to which the emulsion or solely the hydrocarbon must be distributed.

Even in the event that the emulsion needs to be kept in the storage tank for a preset period, it is possible to make the mixture recirculate in the mixing circuit 4 in order to restore the correct structural characteristics of the emulsion.

Variants of the above-described plant and/or method can be envisaged. For example, two or more tanks separate from one another can be used.

Claims

1. A piant for producing a water and hydrocarbon emulsion comprising:

- a mixing circuit (4) for mixing water with a hydrocarbon and obtaining said emulsion;

- a water supply circuit (2) in said mixing circuit (4);

- a hydrocarbon supply circuit (3) in said mixing circuit (4); and

a transfer pipe (41) for conveying said emulsion from the mixing circuit (4) to at least one user (U);

characterized in that said mixing circuit (4) comprises at least two tanks (16a, 16b) separated from each other and a pipe (13) connecting said tanks (16a, 16b) in order to transfer the emulsion from one tank to the other.

2. The plant according to the preceding claim, characterized in that each tank (16a, 16b) comprises an inlet (30) associated with said hydrocarbon supply circuit (3) in order to feed the hydrocarbon directly into the tank (16a, 16b) and an outlet (31) associated with a first inlet end (13a) of said connecting pipe (13).

3. The plant according to the preceding claim, characterized in that said first inlet end (13a) of the connecting pipe (13) is connected to said water supply circuit (2) to enable mixing of the water and hydrocarbon leaving at least one of said tanks (16a, 16b).

4. The plant according to claim 2 or 3, characterized in that said connecting pipe (13) comprises a second outlet end (13b) which is opposite the first end ( 3a) and associated with the inlet (30) of each tank (16a, 16b) in order to convey the water and hydrocarbon mixture into one of said tanks (16a, 16b).

5. The plant according to any one of the preceding claims, characterized in that said connecting pipe (13) further comprises at least a static mixing member (34).

6. The plant according to any one of the preceding claims, characterized in that said connecting pipe (13) comprises a dynamic mixing member (35).

7. The piant according to any one of claims 2 to 6, characterized in that it further comprises a circuit for supplying at least one additive (18) and associated with the inlet of each tank (16a, 16b) in order to feed the additive directly into the tanks (16a, 16b).

8. The plant according to the preceding claim, characterized in that said hydrocarbon supply circuit (3) comprises a hydrocarbon feed device (17) and preferably in that said additive supply circuit (18) comprises a pump (25) situated upstream of the inlet (30) of the tanks (16a, 16b) in order to feed a predefined amount of additive into one of said tanks (16a, 16b).

9. The plant according to any one of the preceding claims, characterized in that said water supply circuit (2) comprises a pump (12) for feeding a predefined amount of purified water into said mixing circuit (4) and preferably a reverse osmosis unit (8) for purifying the water entering the mixing circuit (4) situated upstream of said reverse osmosis unit (8).

10. The plant according to any one of the preceding claims, characterized in that said connecting pipe (13) comprises a pump (36) situated downstream of the first end (13a) of the pipe (13) itself in order to draw a predefined amount of mixture leaving one of said tanks (16a, 16b) into said first end (13a).

11. The plant according to one or more of claims 8 to 10, characterized in that it further comprises a control system (37) operatively engaged with the pump (25) of the additive supply circuit ( 8) and with the hydrocarbon feed device (17) in order to synchronize the feeding of the hydrocarbon with the feeding of the additive into one of said tanks (16a, 16b).

12, The plant according to one or more of claims 8 to 1 , characterized in that said control system (37) is operative!y engaged with the pump ( 2) of the water supply circuit (2) and with the pump (36) of the connecting pipe (13) in order to synchronize the feeding of the mixture leaving one of said tanks (16a, 16b) with the feeding of the water into the mixing circuit (4).

13. The plant according to claim 4, characterized in that each tank (16a, 16b) comprises a cavitation device (33a, 33b) associated with the second outlet end ( 3b) of the connecting pipe (13) in order to emulsify the mixture contained in the pipe (13) itself.

14. The plant according to claim 4, characterized in that said transfer pipe (41) is associated with the connecting pipe (13) upstream of the respective second outlet end (13b) in order to transfer the emulsion obtained in the mixing circuit (4) toward said user (U).

15. A method for producing a water and hydrocarbon emulsion comprising the steps of:

- feeding a hydrocarbon into a mixing circuit (4);

- feeding water into said mixing circuit (4) in order to mix said water with the hydrocarbon; and

- ricirculating the water and hydrocarbon inside the mixing circuit (4) to obtain an emulsion;

characterized in that said step of ricirculating the water and hydrocarbon comprises the steps of transferring the water and hydrocarbon mixture from one tank (16a, 16b) to another a predefined number of times.

16. The method according to the preceding claim, characterized in that it further comprises the step of feeding an additive simultaneously with the step of feeding the hydrocarbon, preferably in a controlled manner.

17. The method according to the preceding claim, characterized in that said steps of feeding the additive and feeding the hydrocarbon comprise the sub-steps of:

distributing a predefined amount of hydrocarbon and of additive into one of said tanks (16a, 16b);

mixing said hydrocarbon and said additive inside the same tank (16a, 16b); and

feeding said hydrocarbon and said additive mixed together to a pipe (13) connecting said tanks (16a, 16b), said pipe (13) placing the tanks (16a, 16b) in fluid communication with each other.

18. The method according to the preceding claim, characterized in that said step of feeding the water comprises the sub-step of distributing a predefined amount of water into said pipe (13) connecting said tanks (16a, 16b).

19. The method according to the preceding claim, characterized in that said step of distributing a predefined amount of water and said step of feeding the hydrocarbon and additive mixed together, are carried out simultaneously in a first inlet end (13a) of the connecting pipe (13) in order to mix said water, said hydrocarbon and said additive, preferably in a controlled manner.

20. The method according to any of claims 15 to 19, characterized in that said step of transferring the mixture comprises a sequence of sub-steps of: conveying the mixture from the first end (13a) of the connecting pipe (13) to a second outlet end (13b) of said pipe (13); filling at least a first (16a) of said tanks with said mixture leaving the second end (13b) of the pipe (13);

completely emptying the first tank (16a) of said mixture, conveying the mixture back to the first inlet end (13a) of the connecting pipe (13);

further conveying the mixture from the first end (13a) of the connecting pipe (13) to the second outlet end (13b) of said pipe (13);

filling at least a second (16b) of said tanks with said mixture leaving the second end (13b) of the pipe (13); and

further conveying the mixture from the first end (13a) of the connecting pipe (13) toward the second outlet end (13b) of said pipe (13).

21. The method according to the preceding claim, characterized in that said step of conveying the mixture from the first end (13a) of the connecting pipe (13) to the second end (13b) of said pipe (13) is carried out by making the water, additive and hydrocarbon mixture pass through at least a static mixing member (34) and/or at least a dynamic mixing member (35).

22. The method according to claim 20 or 21 , characterized in that it further comprises, following the step of transferring the mixture, the steps of: withdrawing the emulsion upstream of the second end (13b) of the connecting pipe (13); and conveying said emulsion to at least one user (U).