Drop recovery system and associated method

1. A drop recovery system comprising:

a circulation conduit for the circulation of a working fluid, the circulation conduit comprising an outlet,

a device for introducing and circulating a working fluid into the circulation conduit, the working fluid comprising a plurality of pockets, each pocket comprising a carrier fluid and a pocket containing a drop of internal fluid, the internal fluid being immiscible with the carrier fluid, each pocket being isolated from the following pocket by a separator, each separator being made up of a separator fluid that is immiscible with the carrier fluid,

a recovery substrate for receiving the pockets of the working fluid, the recovery substrate comprising several compartments, a compartment being placed opposite the outlet of the circulation conduit,

a relative displacement device for moving the substrate with respect to the circulation conduit, the displacement device configured to successively place the outlet of the circulation conduit opposite at least two different compartments of the substrate, and

wherein the recovery system further comprises:

a preparation device connected to the circulation conduit at a location downstream of the device for introducing and circulating a working fluid, the preparation device receiving the working fluid having said plurality of pockets and said separator fluid therein and being configured to inject, into the circulation conduit, an additional volume of separator fluid and an additional volume of carrier fluid, such that the volume of at least one separator is greater than or equal to a critical separation volume, and such that the volume of at least one bubble formed by a pocket and at least a part of said separator is greater than or equal to a critical detachment volume,

a tube defining a part of the circulation conduit for the working fluid, the tube emerging on an open mouth at the outlet of the circulation conduit, the tube comprising an outer wall, and

a nozzle having a through passage, the tube being placed in the through passage of the nozzle,

wherein the circulation conduit is substantially vertical at the outlet.

2. The drop recovery system according to claim 1 , comprising:

a blower unit able to inject a flow of air into the through passage such that a part of the air runs along the outer wall of the tube up to the mouth of the tube.

3. The drop recovery system according to claim 2 , wherein the blower unit is able to inject a continuous flow of air into the through passage.

4. The drop recovery system according to claim 2 , wherein the tube and the nozzle have a same axis of symmetry and the tube is centered relative to the nozzle.

5. The drop recovery system according to claim 2 , wherein the inner passage has a polygonal shape, the outer wall of the tube being fitted in the polygon.

6. The drop recovery system according to claim 1 , comprising a control unit able to control the quantity of separator fluid and/or carrier fluid injected into the circulation conduit by the preparation device for the distribution of the pockets.

7. The drop recovery system according to claim 1 , wherein the circulation conduit has a wider area, the preparation device for the distribution of the pockets being able to inject the additional volume of separator fluid into the wider area.

8. The drop recovery system according to claim 1 , wherein the circulation conduit has an injection area for the carrier fluid and an injection area for the separator fluid located downstream from the injection area for the carrier fluid.

9. The drop recovery system according to claim 1 , wherein the separator fluid is a gas.

10. The drop recovery system according to claim 1 , wherein the preparation device for the distribution of the pockets is able to inject, into the circulation conduit, an additional volume of carrier fluid, such that the volume of at least one pocket is strictly less than a critical fragmentation volume.

11. A drop recovery method comprising the following steps:

introducing and circulating a working fluid into a circulation conduit comprising an outlet, the working fluid comprising a plurality of pockets, each pocket comprising a carrier fluid and a pocket containing a drop of internal fluid, the internal fluid being immiscible with the carrier fluid, each pocket being isolated from the following pocket by a separator, each separator being made up of a separator fluid that is immiscible with the carrier fluid,

recovering at least one pocket, in at least one compartment of a recovery substrate including several compartments, said compartment being placed opposite the outlet of the circulation conduit,

the relative displacement of the substrate with respect to the circulation conduit, so as to successively place the outlet of the conduit opposite at least two different compartments of the substrate,

wherein

the circulation conduit comprises a tube defining a part thereof for the working fluid, the tube emerging on an open mouth at the outlet of the circulation conduit, the tube comprising an outer wall;

the tube is placed in a through passage of a nozzle, and

the circulation conduit is substantially vertical at the outlet, and

wherein the method further comprises:

the preparation of the distribution of the pockets comprising:

a preparation device connected to the circulation conduit for receiving the working fluid having said plurality of pockets and said separator fluid therein, said preparation device injecting into the circulation conduit an additional volume of separator fluid, and

injecting into the circulation conduit an additional volume of carrier fluid,

the preparation of the distribution of the pockets being such that the volume of at least one separator is greater than or equal to a critical separation volume and the volume of at least one bubble formed by a pocket and a part of said separator is greater than or equal to a critical detachment volume.

12. The drop recovery method according to claim 11 , wherein the circulation conduit is defined by a wall and the recovery comprises:

the discharge at the outlet of the circulation conduit of a pocket and part of the separator, said pocket and said part of the separator forming a bubble having a volume greater than or equal to the critical detachment volume, the pocket detaching from the wall of the circulation conduit, and moving into the compartment of the substrate located opposite the outlet.

13. The drop recovery method according to claim 11 , comprising:

the discharge through the outlet of the circulation conduit of a separator having a volume greater than or equal to the critical separation volume, during the movement of the substrate relative to the distribution conduit between a first compartment and a second compartment, such that the pocket following the separator arrives at the outlet of the circulation conduit, when the outlet of the conduit is opposite the second compartment.

14. The drop recovery method according to claim 11 , wherein the separation volume is determined on the basis of the movement speed of the displacement device, the distance between two different compartments of the substrate and the flow rate of the working fluid in the circulation conduit.