WO2013164554A1

WO2013164554A1 - Method for recovering hydrocarbons from a sludge and device implementing such a method

Info

Publication number: WO2013164554A1
Application number: PCT/FR2013/050996
Authority: WO
Inventors: Patrice Capeau; Michel Lopez; Pascal Gendrot
Original assignee: Orege
Priority date: 2012-05-04
Filing date: 2013-05-03
Publication date: 2013-11-07
Also published as: FR2990212A1; FR2990212B1

Abstract

1 ABSTRACT The present invention concerns a method and device for recovering hydrocarbons from a sludge. The flow being formed from at least two partial flows, a quantity of salt predetermined by volume of treated sludge is added to these flows continuously or in batches, the two flows are projected onto one another in a closed chamber having a small volume, simultaneously injecting air at a flow rate d, a mixture of foam, water and suspended matter is recovered in the upper portion of the chamber, the mixture is then left to settle to separate, by decantation, the suspended matter and the supernatant foam created in this way, loaded with hydrocarbons, and the foam is recovered by liquefying it with an additive, to obtain a supernatant of concentrated hydrocarbons separated from the liquid and from the solid matter by continuously withdrawing the liquid portion. Figure 1

Description

PROCESS FOR RECOVERING HYDROCARBONS FROM A SLUDGE AND DEVICE IMPLEMENTING SUCH A METHOD

The present invention relates to a method for recovering hydrocarbons from sludge contaminated with such hydrocarbons.

The process thus makes it possible to eliminate them almost entirely, by lowering in particular the level of hydrocarbons below a determined threshold acceptable by the environment.

The invention also relates to a sludge treatment device implementing such a method.

It finds a particularly important, although not exclusive, application in the field of the decontamination of sludge or waste water containing petroleum effluents, which are heavily loaded with hydrocarbons, the hydrocarbon industrial sludges being able to contain, for example, more than 5% by weight. hydrocarbon weights.

It results surprisingly from the use of a very high energy in a liquid and muddy medium, after increasing the polarity of the medium to facilitate the separation of hydrocarbons.

Processes for recovering hydrocarbons mixed with a liquid or muddy effluent are known.

The techniques for trapping hydrocarbons that exist essentially consist of fixing them by the addition of various reagents, or by separation by centrifugation, for example.

All these known treatments of the prior art have disadvantages, either related to a consumption of reagents often expensive, due to difficulties of treatment and / or conditioning of secondary waste obtained after purification.

The present invention aims to provide a method and a device better than those previously known to the requirements of the practice, in particular that it will allow to recover more hydrocarbons with the devices of the prior art. With the invention water can be separated from the solid parts of the treated sludge by lowering the hydrocarbon content in the separated waters below 100 mg per liter of water, see 5 mg / l and in the separated sludge below. 2% by volume, and very quickly, the use of the method according to the invention requiring only a few seconds or minutes before obtaining a result.

It also has a very low power consumption and uses little consumable material (compressed air, additive).

In addition, the method implements a compact device, easily transportable, which will therefore be able to be installed on inaccessible sites.

The invention allows continuous operation, and this with low operating constraints, while generating no pollution and thanks to a much cheaper technique than those known.

Finally with the invention surprisingly obtained on one side a porous cake and dewatered washed of its new type of hydrocarbons constituting a usable residue, and on the other side a water reusable in the environment, possibly after a complementary simple treatment.

For this purpose, the invention proposes in particular a method for recovering hydrocarbons from a sludge fed with a continuous flow at a flow rate _EB = V / hour, where V is a volume, characterized in that the flow being formed of at least two partial flows of sludge, it comprises the following steps:

a) a predetermined amount of salt, per volume of treated sludge, is added to these streams continuously or batchwise,

b) the two flows are projected onto one another in a closed chamber of volume v <V / 20 by simultaneously injecting air therein at a flow rate d,

c) recovering in the upper part of the enclosure a mixture of foam, water and suspended matter, d) said mixture is allowed to stand in a recovery vessel to separate by settling of the liquid part of the stream thus treated, on one side the suspended materials which fall in the lower part of the container to form a cake, and on the other side the created foam which is loaded with hydrocarbons and,

e) recovering said foam by liquefying it by adding an emulsion breaker additive, while continuously withdrawing the liquid portion, to obtain a concentrated hydrocarbon supernatant separated from the liquid and solids.

The predetermined amount of salt depends on the effluent and its flow rate and will be evaluated by those skilled in the art during a pre-treatment adjustment. By closed enclosure is meant a vessel or a reactor of defined closed volume comprising, however, and of course the inlet means of the continuous flow, and outlet means (generally a tubing) of said continuous flow once treated.

The enclosure is thus an enclosure for passing the flow under pressure.

By a value v <V / 20 is meant a value less or less, with a tolerance of the order of + _ 10% to 20%.

Advantageously v ≤ V / 25 or ≤ V / 30.

For example, for a flow rate of 5m ³ / h (ie a volume V = 5), it comes v <250 1.

In advantageous embodiments, one and / or the other of the following provisions is also used:

the added salt is sodium chloride;

the predetermined amount of salt is between 0.1 g and 5 g per liter of sludge (by volume);

the emulsion breaker additive is a sulphonic fatty acid salt injected continuously in an amount of from 15 to 220 ppm by weight relative to said emulsion;

the flow is injected into the chamber of volume v <V / 20 by two opposite opposite orifices facing each other situated in the lower half of said chamber, the air being injected below said orifices and discharged continuously or by intermittently flow in the upper part, for example by means of a pressure relief valve triggering above a determined threshold value; the air is injected with a flow rate of> 1.5 Ω _EB , for example greater than 5 Ω _E B, at 10 Ω _E B ¼ between 1.5 times and 15 times Ω _EB;

the air is injected at medium pressure. By average pressure is understood to be between 1.4 bar and 2.5 bar, advantageously between 1.6 bar and 1.9 bar. Such pressure generates larger bubbles that will be able to better penetrate the environment by randomly distributing in the enclosure;

- the recovery container is emptied permanently by overflow;

- v <V / 50;

- v <V / 100;

the flow rate Q _EB is greater than or equal to 15 m 3 / h, the flow rate d is greater than or equal to 25 m 3 / h and the relative pressure in the enclosure is greater than or equal to 0.8 bar;

the flow rate Q _EB is greater than or equal to 20 m 3 / h, the flow rate d is greater than or equal to 50 m 3 / h and the relative pressure in the enclosure is greater than 1.2 bar;

at least one liquid reagent is added continuously at a flow rate q inside the enclosure;

the liquid reagent is an organic flocculant of cationic type;

the effluents are degassed at the outlet of the enclosure and the gases obtained are used to supply the air injection at the bottom part;

the cake obtained is recovered and dehydrated by drying, pressing or centrifuging to obtain a solidified cake.

The invention also proposes a device implementing the method as described above. It also proposes a device for recovering hydrocarbons from a slurry charged with hydrocarbons fed with a continuous flow at a flow rate Q _EB = V / h, V being a volume, characterized in that it comprises

a closed chamber of volume V <V / 20 comprising at least two opposite opposite orifices opposite in the lower half of said enclosure, means for capturing the sludge and feeding into said enclosure of the mud flow and captured in at least two partial flows respectively injected each by one of said orifices,

means for injecting a determined quantity of salt into the streams,

means for supplying the enclosure with air at a flow rate below said orifices,

flow evacuation means when the pressure in the enclosure exceeds a predetermined threshold value, a container for recovering and decanting suspended matter from the stream thus treated,

means for recovering the supernatant foam, emulsion breaking feed means for said foam and recovering the hydrocarbon supernatant thus obtained, and

means for continuously discharging the liquid part outside said container.

Advantageously, the device is arranged so that the flow is discharged from the enclosure in the upper part by means of a pressure relief valve triggering above said determined threshold value.

In an advantageous embodiment v <V / 50. Also advantageously v <V / 100. The invention also proposes a device in which the means for feeding a liquid reagent at a determined flow rate directly into the chamber are provided.

The invention will be better understood on reading the following description of embodiments given below by way of non-limiting examples. The description refers to the accompanying drawings in which:

Figure 1 is a block diagram illustrating the method of treatment according to the invention.

FIG. 2 is an operating diagram of an embodiment of a device according to the invention comprising two substantially identical successive steps.

Fig. 3 is a diagram schematically illustrating n + 1 processing steps with a device according to another embodiment of the invention.

Figure 1 shows the principles of the HC hydrocarbon recovery process from an injected sludge B, according to an embodiment of the invention.

In a reactor 1 formed of a chamber 2, oblong, extending around an axis 3, of small volume v for example of the order of 50 liters, the sludge (arrows 4) is injected by two opposite connections 5 , 6, symmetrical with respect to the axis 3 of the enclosure.

The taps are located in the lower part of the enclosure, for example at a distance h from the bottom 7 of the enclosure between the fifth and the third of the height H of the enclosure. These two taps located facing each other allow a pressure supply of the sludge flow heavily loaded suspended material (MES), (for example τ MES 10% / total weight) and hydrocarbons (For example τ hydrocarbons of the order of 5% / total weight). This power supply opposite brings a significant shock at the meeting of the two flows in the zone 8.

In other words, the pumping of sludge from the outside by the pump P introduced into the enclosure of the reactor 1 of small size, by the two taps in face to face allows a shock between the flows in the zone 8 of the fact the outlet pressure of the supply pump or pumps P which depends on the water height of said feed pumps upstream of the connections and losses of the circuit.

Conventionally, using commercial industrial pumps and a circuit without too many accidents, a pressure of 2 bar at the outlet 9 of the connections in the enclosure is easily achievable.

The kinetic energy of pumping is then transformed into shock energy, maximized by increasing the rate of introduction into the chamber for the outlet of the taps by nozzles 9, of reduced dimensions but compatible with the maximum particle size of the sludge. .

Moreover, and according to the embodiment of the invention more particularly described here is introduced a quantity of compressed air (arrow 10) below the zone 8.

By overpressed is meant a slight overpressure which can be between 0.1 bar relative and 1 bar relative to the atmospheric pressure, for example 0.8 bar relative.

This introduction of air is done by a ramp 11 of air distribution, for example a ramp formed by a circular pipe, serpentine or slender, to bring air bubbles distributed on the surface of the air. enclosure, through orifices 12, distributed along said pipe 13.

The air can also be brought by a quilting at the bottom.

The ramp is located below the effluent meeting point in zone 8, for example between the tenth and fifth of the height H of the chamber, and generates large bubbles B, for example bubbles with a diameter of between 1 mm and 1 cm.

This introduction of air increases the energy level of the chamber, in excess pressure with respect to its exit 14 effluent discharge after treatment.

In the upper part 15 of the enclosure is also obtained a functional zone 16, in which an extremely turbulent mixture animated with Brownian motions (interrupted line 17) is produced.

In the lower part 18 of the reactor, in a manner known per se, there is provided a purge 19 of too dense elements that do not escape from above the reactor and which is emptied sequentially.

According to the invention, provision is made for adding a salt S, for example sodium chloride NaCl, to the sludge streams entering, for example, a little downstream of the pump P, for example by means of a pump metering device (not shown) fed by a tank preparation of a water + salt mixture (not shown).

At the outlet 14 of the reactor escape the air and a mixture of water, hydrocarbon foam and suspended solids which, after decantation, will give in the tank R separation separation, a transparent water E physically separated solid material M, with a very low solids content, in particular less than 30 mg / l or even 10 mg / l, whereas initially it could be close to 500 mg / l and the hydrocarbons HC, supernatant, from foam treated with an emulsion breaker C for example introduced in line on the mixture.

The solid material M obtained at this level is more porous and subsequently easily compactable. It can even, depending on its initial organic matter content, be directly permeable out of the reactor.

The air is introduced at an average pressure, for example between 1.6 bar and 1.9 bar absolute at the pressure in the chamber itself, so that there can be large bubbles in the medium, which will be able to penetrate and distribute randomly in the reactor to achieve the expected mixture.

The air is also introduced at a high flow rate, that is to say 1.5 times to 15 times that Q _EB of the incoming water.

The gas extracted from the reactor comes out with the water, the foam and the suspended solids at the flow rate of the booster and can be recovered, treated and if necessary recycled for reuse in the lower part of the reactor. Note that the presence of coarse materials like sand, gravel etc, increases the number of shocks and thus improves the process.

The pressure of the chamber is arranged and / or adjusted to optimize the internal energy by generating a rising flow coming from above.

Such a pressure is therefore determined according to the functional characteristics of the circuit (pump water height) but also the type of effluents and the desired treatment rates.

The finally chosen size of the reactor will also be determined by those skilled in the art based on the basic knowledge of the engineer in the field of chemical engineering and flow diagram.

The pressure and the output are for example ensured by means of a valve valve which releases the flow when the given pressure is exceeded.

Since the process according to the invention uses stirring in three phases, solid, liquid and gaseous, it is necessary to leave a separation taking account of degassing, of the solid phase denser than water and of evacuation of water.

In an advantageous embodiment, a flocculant is additionally added, for example a polymer known per se.

This additional addition is done in the functional zone 16, and in proportions ranging from 0.05 to 0.1% of the dry matter content contained in the sludge, that is to say in proportions well below the proportions usual in case of conventional coagulation / flocculation treatment. By way of comparison, the content used in the usual treatments is of the order of 1 to 1.5% of the dry matter content contained in the sludge.

Thus, with a 55-liter diameter reactor and injection nozzles in this 40 mm diameter reactor, it is possible to treat up to 20 m ³ / h of sludge.

Surprisingly, it is also observed with the process of the invention that when the pressure in the reactor is greater in relative pressure than 0.8 bars, that the feed rate Q _EB of the muddy waters for example formed by sludge 5% MES loaded, said MES being derived from the biological degradation of marsh grass, clay, sand and various petroleum residues is greater than 15 m ³ / h and that the air flow d is greater than 25 m ³ / h, an exceptional separation is obtained with a maximum settling speed of a sludge which after drying has a new granular porous appearance.

With a 55-liter reactor and effluent injection nozzles within 40mm, extremely fast percussion velocity values and particularly short residence times in the reactor, such as in the reactor from 40s to 5 m ³ / h.

Thanks to the invention it is therefore possible to obtain a much higher dehydration than that obtained using existing techniques and this in a few seconds.

In addition to this considerable time saving in the treatment, very low power consumption, compressed air and salt are necessary. The small size of the enclosure also makes it easily transportable, and allows its installation in difficult access sites, while allowing a continuous operation of great simplicity.

The treatment according to the invention does not generate any pollution, and this with a much more economical installation compared to other treatment systems that can be envisaged for the sole work of liquid / solid separation, such as centrifuges, press filters, filter belts etc.

FIG. 2 shows an operating diagram of a device 20 according to one embodiment of the invention.

The device 20 allows the separation between the liquid part, the hydrocarbon foam and the material in suspension of the sludge fed at 21 in continuous flow at a flow rate Q _EB = V / h, the supply of 21 then separating in two to feed tapping 22.

More specifically, the device 20 comprises a first closed stainless steel enclosure K of volume V <V / 20, for example 55 liters for a flow rate Q = V / h of 1.5 m ³ / h, comprising at least two identical or opposite ports 22, opposite, located in the lower half 23 of the enclosure, for example at a distance equal to one third of the height of the enclosure.

The enclosure K is for example constituted by a cylindrical portion 24 terminated in the upper part and in the lower part by two identical conical zones 25, for example with angles at the apex of the order of 120 °. Each end is itself terminated by an upper tube 26, and lower 27. The lower tube 27 is connected to an intermittent discharge pipe 28, provided with a valve 29, the suspended material 30 which would have been decanted into the bottom 27 of the enclosure.

The device 20 further comprises means 31 for supplying the air chamber 32 at a flow rate below the orifices 22.

This supply is for example via a straight pipe or tube 33, of small diameter, for example 5 cm in diameter, of length substantially equal to the diameter of the cylindrical chamber, comprising nozzles 34 regularly distributed, compressed air outlet distributed throughout the chamber, creating significant bubbles that will cause significant brewing (round 35).

Means 36 known per se, for feeding a liquid reagent 37, for example a flocculation polymer, are provided. They are for example formed of a storage tank 38, feeding via a metering pump 39 and a remotely controlled valve 40, the inside of the enclosure above the taps 22, in the turbulence zone. .

According to the embodiment of the invention more particularly described here, the device 20 comprises feed means by metering pump (not shown) in salt S on the pipe 21.

The device 20 further comprises means 41 for continuous discharge of the sludge after passing through the chamber via a valve or valve 42 which opens beyond a determined pressure in the chamber, for example 1.3 bar.

It is also possible not to provide a valve, the downstream circuit itself constituting the pressure drop required to maintain relative overpressure of the enclosure.

The effluent 43 is then evacuated at the top to end in a tank 44 decantation known in itself.

For example, this settling tank 44 is constituted by a cylindrical tank 45 into which the plumbing discharge pipe 46 plunges to limit turbulence.

It is then observed that the mixture that arrives through the pipe 46 separates into a liquid portion 47, a foamy supernatant 48 containing the hydrocarbons and the solid material 49.

The decanted solid material 49 is discharged at the bottom 50 for subsequent treatment.

The liquid part 47 is withdrawn above a determined level 51 by a pump 52 in a pipe 21 'supplying a second chamber K' identical to the first chamber K.

The foam 48 is suctioned by a vacuum cleaner 53 above a determined second level. An emulsion breaker 54 is introduced at 55 on the circuit, for example at the level of the vacuum cleaner, the emulsion thus broken being reintroduced by a circuit 56 on the pipe 21 'to be reintegrated to the circuit. The emulsion breaker or breaker is, for example, a sulphonic fatty acid salt, for example the product ANTICOR BE 030 from the company SCOMI. In another embodiment, the emulsion breaker is introduced directly into the reactor K or K '

In the remainder of the description, the same reference numbers will be used as for the first enclosure, with one to designate the same elements of the second enclosure.

The sludge, which has thus already been treated a first time, is treated again in a second high-energy mixing reactor constituted by the enclosure K 'and its circuits, generating a new washing, this time a sludge pre-decontaminated and practically free from suspended solids thanks to the first settling.

A complementary salt addition (Chloride

Sodium) is provided at 57 by metering pump, supplying the circuit with saline liquid with a continuous flow and / or in batch according to quantities determined as a function of the effluent treated, for example between 0.1 g and 5 g of salt. for 1 liter of mud passing in the pipe 21 '.

The passage through this second reactor stage complementary to the first, makes it possible to further lower the level of hydrocarbon in the liquid 47 'obtained, the liquefied hydrocarbons HC after complementary breaking by adding at 55' the breaker product 54 '(identical or not to breaker product 54) for example on the pipe 46 'of the enclosure K' exit supernatant at the top of the tank 45 '.

The liquid part is withdrawn continuously at 51 'at an intermediate operating level, the hydrocarbons are in turn evacuated at 58 for example by overflow. FIG. 3 shows an embodiment of a device comprising several stages of successive washes and foam breakage of a sludge 60 introduced upstream of reactors R1, R2, ... Rn, for example identical to those (and / or the speakers) described with reference to Figures 1 and 2.

Each reactor is associated with a settling tank B1, B2,... Bn which will make it possible to recover the solid slabs S1, S2,... Sn in the lower part and the foams M1, M2,... Mn obtained by fractional addition of NaCl salt upstream of each reactor and increasingly concentrated in hydrocarbons, before definitive breaking at 62, treatment with a final reactor Rn + 1, and final settling in the tank Bn + 1, hydrocarbons Hc liquids being recovered in the upper part 63 and continuous tray Bn + 1, and the decontaminated liquid in the lower part 64, continuously for use in the environment for example.

We will now describe with reference to Figure 2 the operation of a purification according to the embodiment of the invention more particularly described here.

From a medium for example a storage tank and / or a settling tank loaded with hydrocarbon sludge, this sludge is pumped out.

In an example of application the sludge rate, i.e. the percentage by mass material solids, is for example between 3 and 10% and the hydrocarbon content is 5% by weight.

This slurry supplies the enclosure K, for example with a volume V = 100 l, at a flow rate for example between 5 and 50 m ³ / h, for example 15 m ³ / h. Simultaneously and online Sodium Chloride dissolved in water is introduced, with a metering pump, with a concentration of 1 g per liter of sludge to be treated.

As described above, this slurry then loaded with salt is injected into the reactor by the two taps 22 vis-à-vis. Simultaneously air is supplied by the lower ramp 33 of the reactor with a flow rate greater than 25 m ³ / h, for example.

The pressure inside the latter is between 0.3 and 1.5 bar relative, for example greater than 0.8 bar relative, depending on the water height of the pump and / or the pumps of supply of the effluents, as well as the pressure drop created by the enclosure itself and by the discharge valve 42 located in the upper part of said enclosure.

The pressure inside the reactor can in particular be regulated via this upper valve or valve.

The effluent thus stirred and supplied with air, remains in the reactor for a period corresponding to the relative ratio between flow rates, volume and pressure.

It is therefore preserved for example during a residence time of a few seconds, for example less than 1 min before being evacuated.

This time can even be very low since with an effluent flow rate greater than 20 m ³ / h, for example, it is possible to remain in the enclosure for a time shorter than

10 seconds.

The mud feed rate has a direct effect on the percussion speed, knowing that the time of contact and residence in the reactor under pressure also affects the rate of formation of the flocs and their settling.

The air flow and the influence of the pressure in the reactor are also elements which, in view of the desired result, will be adapted, so as to reach the skilled person.

The mixture of foam, liquid and suspended matter leaves the reactor at a pressure corresponding to the flow pressure of the flow of fluid in the pipe 43, and feeds the settling tank 45, in which the settling will be carried out in a known manner in herself.

The foam 48 loaded with hydrocarbon is collected in the upper part of the tank to be broken at 53 and reinjected.

The water is obtained by supernatant. It is already of high purity and is evacuated itself continuously at 51, to be treated again as described above by the second reactor (enclosure K ') etc.

The mud obtained at the bottom of the settling tank is evacuated either continuously or discontinuously, according to specific periods, for example once a day. It is observed that it has a derisory hydrocarbon rate.

Re-evacuating this sludge very quickly increases its quality especially as regards its good porosity.

The reliquefied foam and the liquid phase after treatment in a manner identical to that just described, is recovered in the settling tank 45 ', the water and the mud virtually free of any hydrocarbon being recovered in the lower part and the hydrocarbons in the upper part.

As is obvious and as also follows from the above, the present invention is not limited to the embodiments more particularly described. On the contrary, it embraces all the variants and in particular those where the orifices may be nozzles, tubes penetrating inside the enclosure to minimize the distance between the outlets and increase the force of the shocks, the salt used is another salt as Sodium Chloride (Potassium Chloride) etc.

Claims

1. Process for recovering hydrocarbons from a hydrocarbon-loaded sludge fed with a continuous flow at a flow rate _EB = V / hour, V being a volume, characterized in that the flow is formed by at least two streams partial, it comprises the following steps:

a) a predetermined amount of salt per volume of treated sludge is added to these streams continuously or batchwise,

c) recovering in the upper part of the enclosure a mixture of foam, water and suspended matter, d) is then allowed to rest said mixture in a recovery vessel to separate by settling of the liquid part on one side the suspended materials of the stream thus treated which fall in the lower part of the container to form a cake and on the other side the supernatant foam thus created charged with hydrocarbon,

e) recovering the foam by liquefying it with an additive to obtain a concentrated hydrocarbon supernatant separated from the liquid and solids by continuously withdrawing said liquid portion,

2. Process according to claim 1, characterized in that the added salt is chlorine of

Sodium.

3. Method according to any one of the preceding claims, characterized in that the predetermined amount of salt is between 0.1 and 5 g per liter of sludge.

4. Method according to any one of the preceding claims, characterized in that the emulsion breaker additive is a sulfonic acid salt continuously injected in an amount of 15 to 220 ppm by weight relative to said emulsion.

5. Method according to any one of the preceding claims, characterized in that the flow is injected into the chamber of volume v <V / 20 by two opposite opposite orifices opposite in the lower half of said enclosure, l air being injected below said orifices and the flow is evacuated continuously or intermittently in the upper part by means of a pressure relief valve triggering above a determined threshold value.

6. Method according to any one of the preceding claims, characterized in that v <V / 100.

7. Method according to any one of the preceding claims, characterized in that the flow rate Q _EB is greater than or equal to 15 m3 / h, the flow rate d is greater than or equal to 25 m3 / h and that the relative pressure in the enclosure is greater than or equal to 0.8 bar.

8. Method according to claim 7, characterized in that the flow rate Q _E B is greater than or equal to 20 m3 / h, the flow rate d is greater than or equal to 50 m3 / h and the relative pressure in the chamber is greater than 1.2 bar.

9. Process according to any one of the preceding claims, characterized in that add at least one liquid reagent continuously at a rate q inside the enclosure.

10. Method according to any one of the preceding claims, characterized in that after step d), the steps a), b), c) are repeated at least once before recovering the remaining foam and breaking it for recover hydrocarbons

11. A device for recovering hydrocarbon from a slurry charged with hydrocarbon fed with a continuous flow at a flow rate Q _EB = V / h, V being a volume, characterized in that it comprises

means for injecting a determined quantity of salt into the streams,

means for supplying the enclosure with air at a flow rate below said orifices,

means for continuously discharging the liquid part outside said container.

12. Device according to claim 11, characterized in that the flow is discharged at the top through a pressure relief valve triggering above said determined threshold value.

13. Device according to claim 11 or 12, characterized in that v <V / 100.