FR2554738A1 - TOURBILLON EXTRACTOR AND METHOD FOR MIXING A FLUID CURRENT WITH A SECOND LOW PRESSURE FLUID CURRENT - Google Patents

Abstract

A WHIRLPOOL MIXER INCLUDES A SENSITIVELY CYLINDRICAL CHAMBER 10 INCLUDING A PERIPHERAL WALL 11 AND END WALLS 12, 13; A TANGENTIAL ENTRY 14 CROSSES THE PERIPHERAL WALL AND AN AXIAL ENTRY 16 CROSSES ONE 12 OF THE END WALLS; AN OUTPUT 15 CROSSES THE OTHER END WALL SO THAT A HIGH PRESSURE FLUID ENTERING THROUGH THE TANGENTIAL INPUT FORMS A VIRGIN OF FLUID 29 INSIDE THE CHAMBER; A SECOND FLUID ENTERING THE CHAMBER THROUGH THE AXIAL ENTRY IS MIXED WITH THE MATERIAL WHICH IS INJECTED INTO THE TOURBILLON CHAMBER THROUGH THE AXIAL ENTRY. THE FLUID AND THE MATERIAL ARE MIXED TOGETHER IN THE VIRGIN AND EXTRACTED BY THE AXIAL OUTLET.

Description

Vortex mixer and method for mixing a stream of fluid with

  a second stream of fluid under low pressure US Pat. No. 4,333,499 issued June 8, 1982, titled 'tPressure Dissipation Apparatusw, in the name of Jeffrey L. Beck and William T. Sweeney, describes an entry vortex or vortex tangentialIe-at high pressure and axial outlet. The fluids entering the swirl chamber are caused to pass from a low speed under high pressure to a high speed under low pressure when they exit through the axial outlet. Tubing is provided in this device to decrease the high rotation speed

  fluids when they leave the axial outlet.

  Patent application US 439 67I filed on November 8, 1982, entitled "Multipoint Slurry Injection Junction",

  in the name of Ahmed El-Saie, describes a conical structure

  carrying tangential entries which are inclined with respect to the axis of the conical structure. The mud enters the conical structure and mixes with a rotating fluid as it leaves the conical structure. The application describes a means for mixing a fluid such as water or mud with an incoming stream, which may also contain

  water, mud or solids. The device is relative-

  large and therefore expensive to manufacture and

  requires adequate space for installation.

  The present invention teaches another way of mixing solids or fluids such as mud with an incoming stream, and achieves this using a vacuum extractor. whirlwind. Extractors are commonly used to mix solids with high speed currents, and then to convert speed, which is kinetic energy,

  in a pressure, which is potential energy; however

  However, these devices require a constriction in the con-

  pick at high speed. Such a constriction will not allow - 2- not the passage of currents of fluid containing large

  particles, such as schlamms or carbon mud.

  The present invention, on the contrary, does not include any constriction in the input current and, therefore, large particles or particulate matter may -

  be included in the input current without danger of

  significant erosion or erosion of the inlet part of the mixer. The mixer mainly comprises a vortex chamber having a tangential high pressure inlet and an axial outlet. The fluid or mud entering through the tangential inlet will generally have high pressure and low speed. When the sludge comes out of the axial outlet, it will be converted into a medium pressure and high speed fluid. A second axial inlet allows the injection into the vortex of a fluid or a solid at low pressure coming from another source. An ante-vacuum device is provided in the event that the vortex chamber develops a pressure below atmospheric pressure, in order to prevent cavitation

inside the room.

  - More specifically, a first aspect of the invention relates to a vortex mixer which is essentially characterized in that it comprises: (a) a substantially cylindrical chamber comprising a peripheral wall and end walls; (b) a tangential entry crossing said peripheral wall; (c) an axial inlet passing through one of said end walls, and (d) an outlet passing through the other end wall, due to which high pressure fluid entering through said tangential inlet forms a vortex of fluid inside said chamber, this fluid leaving the chamber through said axial outlet, and the material entering through said axial inlet mixing with the fluid in the vortex and leaving through said outlet

  accompanied by the fluid coming from the tangential entry.

  A second aspect of the invention relates to a method for mixing a stream of fluid with a stream under low pressure, characterized in that it comprises

stages consisting of.

  (a) forming a vortex using a fluid under high pressure, said vortex comprising an axis of rotation at low pressure;

  (b) remove the fluid from the vortex by forming an

  rotating fluid velocity including a hollow core; (c) axially injecting said second stream into the hollow core; whereby the second current mixes with the

first material injected.

  The invention will be better understood on reading the

  detailed description which follows given by way of example

  and made with reference to the accompanying drawing, in which: FIG. 1 is a perspective view of the whirlpool mixer, a part of the chamber being partially cut away, illustrating the outlet and rotation of the fluids when they leave the axial outlet, and

  fig. 2 is a side view of the mixer shown

  felt in fig. 1, which also includes a part

  torn away, illustrating the distribution of fluids inside

  laughter of the whirlpool chamber and the outlet.

  With reference to all of the figures and in particular

  culier in fig. 1, a vortex chamber, generally designated by the arrow 10, has an end wall 11, a side wall 12 and a second side wall

  13. A high pressure tangential inlet 14 is shown

  tee so as to open in the chamber 10. An axial outlet 15 is mounted on the side wall 13 so as to open into the chamber 10. An axial inlet 16 is mounted in the side wall 12 and extends into the chamber - 4 - 10. The axial inlet 16 comprises an anti-vacuum device, indicated by arrow 17, intended to allow air to enter inside the chamber 10, as indicated by arrow 21, in the case where the pressure in the chamber becomes lower than atmospheric pressure. Such an arrangement prevents cavitation inside the chamber 10. A valve 18 controls the flow of fluid from an inlet pipe 19 to the inlet 16. The inlet pipe 16 has an extension 20 in the room 10, for purposes which will be explained in the part of

  the description relating to operation.

  The vortex mixer works as follows. The fluids under high pressure penetrate in the direction of arrow 22 into the tangential inlet at high pressure 14. The fluids then pass into the chamber 10 and rotate at high speed along the outer wall of the chamber 10. The speed of rotation causes the material or fluids to flow in the direction of the arrow 23

  to create a vortex region 29 between the extension

  pipe 20 and the axial outlet pipe 15. The material entering the outlet 24 is then rotated at an extremely high speed and at a very low pressure. It will therefore continue to rotate along the pipe 15, as illustrated by the arrow 25. The fluid or the solids can be injected in the direction of the arrow 26 into the pipe 19 through the valve 18 and into the inlet pipe axial 16 which opens into the chamber 10. The fluids will then be injected into the chamber 10 at a pressure slightly greater than that which prevails in the vortex 29 or center of the chamber

  10. This material will then pass to the exit orifice.

  tie 24 of the axial outlet 15, where it will be mixed with the rotating fluids and ejected through the axial outlet

at medium pressure 15.

  Referring to fig. 2, we can observe more -5 - in detail the distribution of fluids. In the chamber 10 will circulate fluids which have been injected therein in the direction of the arrow 22. When they enter the vortex chamber 10, the fluids revolve around the chamber 10. The fluids enter the chamber - bre 10 under high pressure and at low speed, and exit under low pressure and at high speed. As the speed decreases in the downstream part of the outlet 15, there is a partial recovery of the pressure, so that the fluid is under medium pressure and at low speed. The

  fluid or the mud will tend to form a vortex between the ex-

  end of the pipe extension 20 and to flow substantially-

  through hole 24 to enter the hose

  axial outlet 15. The vortex 29 can then receive the

  entry of the pipe 16, in the direction of the arrow 28 entering the vortex 29. In the case where the pipe 16 is too large in relation to the internal diameter of the pipe 15, it is possible that the vortex tends to form also at the inside the pipe 16, to cause a reverse flow of fluid along the pipe 16. If such a situation occurs, the diameters of the pipe 16 and of the pipe 15 must be adjusted (or else the pipe 16 being made smaller, or the pipe 15 being made larger) so

prevent backflow of fluids.

  The extension 20 should extend as far as possible into the chamber 10, in order to help prevent backflow of fluid; however, it should not extend

  too far for the dimension between the end of the extension

  gement 20 of the pipe and the orifice 24 is not less than the diameter of the solid particles injected by the tangential inlet 14. The fluids will then be ejected from the pipe

  16 in the direction of arrow 28 to enter the turn-

  log formed at the orifice 24 of the axial outlet 15. At this point, the fluids will be mixed with a

  fluid at high speed in outlet 15.

- 6 -

  The material entering through the tangential input 14 and the ma-

  The inlet entering through the axial inlet 16 will exit through the pipe in the direction of the arrow 30. It should be noted that the inlet pipe 16 must be of a smaller diameter than that of the axial outlet pipe 15. In fact, the diameter of the axial pipe 15 must be such that it can accept flows from both the inlet pipes 14 and 16. If the air

  entrained inside the whirlpool comes to create a pro-

  problem at any point downstream of the axial outlet 15, a surfactant can then be added via the inlet 31 from a source 32 and will be mixed with the material entering the interior of the vortex chamber 10. Such a surfactant will cause the material inside the outlet 15 to wetting and foaming thereof, thereby producing a more uniform mixture.

downstream of the axial outlet 15.

  The surfactant must be a nonionic surfactant having one of the following compositions: 1) ethoxylated alcohol comprising an alkyl chain between C10O and C18, with an ethoxylation rate between

and 80 percent; -

  2) alkyl phenol ethoxylate comprising an alkyl chain of 8 to 9 carbons and an ethoxylation rate of between 30 and 80 percent; or

  3) block copolymers (block copolymers) of polyoxy-

propylene and polyoxyethylene.

  It is understood that variants or modifications may be made to the device described above without

  go beyond the scope of the invention.

- 7 -

Claims (9)

  1.- Whirlpool mixer, characterized in that it comprises: (a) a substantially cylindrical chamber (10) comprising a peripheral wall (11) and end walls (12,13); (b) a tangential inlet (14) passing through said peripheral wall; (c) an axial inlet (16) passing through one (12) of said end walls; and (d) an outlet (15) passing through the other end wall (13),   this whereby high pressure fluid entering through said tangential inlet forms a fluid vortex (29) inside said chamber, this fluid exiting the chamber through said axial outlet (15), and the material entering through said axial inlet (16) mixing with the fluid-in the vortex and leaving through said   fluid outlet from the tangent inlet tielle (14).   2.- mixer according to claim 1, characterized in that it comprises a valve (18) in series with said axial inlet (16).   3.- Mixer according to claim 1 or 2, charac-   terized in that it includes an anti-vacuum device on said axial entry.   4.- Mixer according to any one of the claims   1 to 3, characterized in that the outlet (15) has a   cross section of surface greater than that of the axial (16).   5.- Mixer according to any one of the claims   1 to 4, characterized in that a non-ionic surfactant is added to the material entering the chamber substantially cylindrical (10).   6.- Method for mixing a stream of fluid with a second stream under low pressure, characterized in that it comprises the steps consisting in: - 8 - (a) forming a vortex (29) using a fluid under high pressure, said vortex comprising an axis of rotation at low pressure; (b) removing fluid from the vortex by forming a rotating fluid envelope having a hollow core; (c) axially injecting said second stream into the hollow core; whereby the second current mixes with the first material injected.   7.- Method according to claim 6, characterized in that air is injected into the second stream before the injection of the latter.   8.- Method according to claim 6 or 7, charac-   terized in that the second stream comprises dry solids.   9.- Method according to any one of claims   6 to 8, characterized in that a non-surface active agent   ion is added to the second stream.