Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
  • B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
  • B04C5/00—Apparatus in which the axial direction of the vortex is reversed
  • B04C5/02—Construction of inlets by which the vortex flow is generated, e.g. tangential admission, the fluid flow being forced to follow a downward path by spirally wound bulkheads, or with slightly downwardly-directed tangential admission
  • B04C5/04—Tangential inlets
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
  • B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
  • B04C5/00—Apparatus in which the axial direction of the vortex is reversed
  • B04C5/12—Construction of the overflow ducting, e.g. diffusing or spiral exits
  • B04C5/13—Construction of the overflow ducting, e.g. diffusing or spiral exits formed as a vortex finder and extending into the vortex chamber; Discharge from vortex finder otherwise than at the top of the cyclone; Devices for controlling the overflow
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
  • B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
  • B04C5/00—Apparatus in which the axial direction of the vortex is reversed
  • B04C5/14—Construction of the underflow ducting; Apex constructions; Discharge arrangements ; discharge through sidewall provided with a few slits or perforations

Definitions

• the field of the invention is that of the design and manufacture of hydrocyclones conventionally used in the effluent treatment sector in order to separate the liquid phase and the solid phase of a mixture.
• Hydrocyclones are commonly used during the treatment of certain effluents in order to proceed to a liquid-solid separation.
• the Applicant uses hydrocyclones in the example implementation of the process marketed under the name of Actiflo ® for the treatment of water. These same hydrocyclones are used in other water treatment processes or industrial effluents.
• a water treatment process of the Actiflo ® type comprises a weighted flocculation step during which the previously coagulated and / or flocculated water is brought into contact with ballast, such as microsand, in order to decant rapidly. the flocs it contains during a subsequent decantation step.
• ballast such as microsand
• This decantation step leads to the production of at least partially treated water and a mixture of sludge and ballast.
• the ballast concentration In order to maintain the performance level of such a treatment process, the ballast concentration must be kept substantially constant during the course of treatment.
• the ballast is recycled during the treatment.
• the mixture of sludge and ballast is conveyed to a hydrocyclone inside which the solid phase composed of ballast is essentially separated from the liquid phase.
• the mixture of liquid, sludge and ballast is introduced under pressure laterally inside the body of the hydrocyclone which has a cylindro-frustoconical internal cavity whose diameter decreases towards the underflow of the hydrocyclone.
• a vortex is created inside the internal cavity tending to press the solid phase against the peripheral wall of the cavity.
• the solid phase then flows towards the underflow of the hydrocyclone while the liquid phase rises towards the overflow of hydrocyclone.
• a mixture of sand and a small amount of liquid and sludge is withdrawn to be at least partially recycled to reintroduce the ballast into the process.
• a mixture of liquid, sludge and a small amount of ballast is extracted in overflow.
• the present hydrocyclones are sensitive to the fluctuations in the concentration of suspended matter (SS) of the water to be treated.
• SS suspended matter
• the SS load of the water to be treated varies greatly over the course of a year.
• the hydrocyclone then has difficulty evacuating the mixture of sludge and ballast underflow: this phenomenon is called "extrusion".
• Part of the sludge and ballast is then discharged in overflow with the treated water which induces losses in ballast and a drop in the quality of the treated water.
• the invention particularly aims to provide an effective solution to at least some of these different problems.
• an object of the invention is to provide a hydrocyclone which is insensitive to fluctuations in the concentration of MES of the effluent to be treated.
• the object of the invention is, according to at least one embodiment, to provide such a hydrocyclone which is not very sensitive to the phenomenon of extrusion.
• Another object of the invention is, according to at least one embodiment, to provide such a hydrocyclone which induces low energy consumption, at least compared to the hydrocyclones according to the prior art.
• an object of the invention is to provide a hydrocyclone which can operate efficiently with a low feed pressure, at least compared to the hydrocyclones of the prior art.
• Another object of the invention is, according to at least one embodiment, to provide such a hydrocyclone which is reliable and / or robust and / or simple in design.
• the invention provides a hydrocyclone comprising:
• a body defining a hollow interior cavity, said hollow interior cavity having an upper portion of cylindrical section extended by a lower portion of frustoconical section, the diameter of said frustoconical section decreasing in the direction of the lower portion of said body;
• an underflow outlet for discharging said substantially separate solids from said liquid, communicating with the lower end of said interior cavity
• an overflow outlet for discharging said liquid substantially separated from said solids, communicating with the upper end of said interior cavity
• underflow outlet extends from the lower end of said lower portion of frusto-conical section and has a frustoconical section whose diameter increases toward the lower portion of said hydrocyclone.
• the implementation of a frustoconical section underflow whose diameter widens towards the bottom of the hydrocyclone helps to maintain the swirling motion of the fluid.
• a hydrocyclone according to the invention is thus less sensitive to variations in the MES concentration of the effluent to be treated.
• the outline of said underflow comprises at least one helical groove whose winding direction is identical to the direction of winding (or circulation) of the liquid inside said internal cavity.
• said at least one groove extends in part on the contour of said lower portion of said interior cavity.
• said helical groove forms a hollow.
• the groove could also project into the interior cavity.
• the length of said underflow is greater than three times the diameter of the junction between the frustoconical lower portion of the inner cavity and the underflow of the hydrocyclone.
• the length of said underflow will preferably be less than or equal to ten times the diameter of the junction between the frustoconical lower portion of the inner cavity and the underflow of the hydrocyclone.
• a shorter length would limit the effect expected by the implementation of the frustoconical underflow, ie improve the liquid-solid separation and make the hydrocyclone less sensitive to changes in the concentration of MES of the effluent to be treated while reducing the supply pressure. Too long a length would however induce a significant loss of load.
• the angle a of the frustoconical section of the underflow relative to its axis of revolution is between 10 and 25 °.
• said overflow outlet comprises a frustoconical pipe which extends in the extension of said cylindrical portion and whose diameter increases in the direction of the upper part of said hydrocyclone.
• said frustoconical tubing comprises an inlet which communicates with said internal cavity and an outlet which opens into a peripheral housing formed in said body, said overflow further comprising a discharge pipe which extends laterally to said body, said tubing discharge device comprising an inlet which communicates with said peripheral housing and an outlet which opens out of said body.
• the overflow of the hydrocyclone is of the overflow type.
• the liquid phase from the inner cavity flows overflow into the peripheral housing constituting a collection box before flowing thereof through the lateral discharge pipe.
• the sludge has an anisotropic flow, that is to say it is different (direction and speed) depending on the location of the hydrocylone where this flow is measured. This results in particular from the rotational movement of the sludge inside the hydrocyclone and the nature of the sludge (layers not perfectly homogeneous). If the evacuation was different from an overflow (eg a pipe), the flow would then be forced and would strongly constrain the vortex that one wishes to maintain.
• the overflow box (overflow collection box) therefore makes it possible not to constrain the flow.
• the angle ⁇ of the frustoconical tubing of the overflow relative to its axis of revolution is between 10 and 30 °.
• said inlet comprises an inlet pipe which extends along a spiral about the longitudinal axis of said body.
• said inlet pipe extends along said spiral over a length between 1 ⁇ 2 and 3 ⁇ 4 of a turn of said body.
• said inlet pipe extends inclined downwards from said body.
• the angle of inclination of said inlet pipe with respect to the transverse axis of said body is less than or equal to 30 °.
• connection of said inlet pipe to said cylindrical portion of said inner cavity is made tangentially. This allows the mixture to be pressed against the peripheral wall of the internal cavity as soon as it enters the hydrocyclone, to improve the liquid-solid separation and to reduce the supply pressure.
• the section of said inlet pipe gradually decreases in the direction of said cylindrical portion.
• the largest section of said inlet pipe is between 30 and 50% of the section of said cylindrical portion, and the smallest section of said inlet pipe is between 20 and 30% of the section. of said cylindrical portion.
• said inlet pipe has a circular section, the connection of said inlet pipe to said cylindrical portion of said inner cavity being made elliptically.
• This also contributes to pressing the mixture against the peripheral wall of the interior cavity as soon as it enters the hydrocyclone, to improve the liquid-solid separation and to reduce the supply pressure.
• the ratio between the small radius and the large radius of said elliptical shaped connection is between 1 and 2.
• the passage of the circular section of said inlet tube to the elliptical shape of the connection thereof to said cylindrical portion of the inner cavity is progressively made.
• the upper contour of said cylindrical portion of said internal cavity extends in a helical manner with a direction of winding identical to the direction of circulation of the liquid inside said internal cavity.
• said upper contour of said cylindrical portion of said interior cavity helically extends from the top to the bottom of said elliptical shaped connection.
• said hydrocyclone comprises means for injecting operating water into said internal cavity, at the junction between said frustoconical lower portion and said underflow.
• Such injection means can act as a fuse if, in an extreme case, the hydrocyclone was to close it.
• FIG. 1 illustrates a front view of a hydrocyclone according to the invention
• - Figure 2 illustrates a sectional view along a plane passing through the longitudinal axis of the hydrocyclone and the axis of the discharge pipe of a hydrocyclone according to the invention
• FIG. 3 illustrates a schematic partial view of the inner contour of the inlet pipe and the upper portion of cylindrical section of a hydrocyclone according to the invention
• FIG. 4 illustrates a schematic view from above of the inlet pipe and of the upper portion of cylindrical section of a hydrocyclone according to the invention
• FIG. 5 illustrates a view from above of a hydrocyclone according to the invention, the upper part of which has been removed;
• FIG. 6 illustrates a side view in transparency of the underflow of a hydrocyclone according to the invention
• Figure 7 illustrates a front view of a variant of a hydrocyclone according to the invention, the inlet pipe is inclined.
• FIGS. 1 to 7 an example of a hydrocyclone according to the invention is presented.
• such a hydrocyclone comprises a body 10 which extends along a longitudinal axis.
• This body 10 comprises a hollow interior cavity 11.
• This hollow interior cavity 11 comprises:
• the frustoconical section here is the trunk of a cone of revolution. Its diameter tends to decrease towards the bottom of the hydrocyclone.
• the hydrocyclone comprises an inlet 12 for a mixture of liquid and solid, for example a mixture of water, sludge and ballast.
• This inlet 12 comprises an inlet pipe 120.
• the axis of this inlet pipe 120 is inclined downwards relative to a transverse axis of the body of the hydrocyclone, that is to say with respect to an axis orthogonal to the longitudinal axis of the body 10, an angle ⁇ less than or equal to 30 ° (see Figure 7).
• the inlet of this pipe 120 is thus higher than its outlet. In a variant, it may not be inclined (see Figures 1 and 2). In this case, it will extend along an axis orthogonal to the longitudinal axis of the body 10.
• the inlet pipe 120 forms a spiral around the longitudinal axis of the body 10. This spiral extends over between 1 ⁇ 2 and 3 ⁇ 4 of the periphery of the body 10.
• the connection 17 of the inlet pipe 120 to the cylindrical portion 110 of the inner cavity 10 is made tangentially.
• the section of the inlet pipe 120 gradually decreases towards the cylindrical portion 110.
• the largest section of the inlet manifold i.e. the section of its inlet, is between 30 and 50% of the section of the cylindrical portion 110, and the smallest section of the tubing of the inlet 120 is between 20 and 30% of the section of the cylindrical portion 110.
• the inlet pipe 120 has a circular section. Its connection to the cylindrical portion 110 of the inner cavity 10 is preferably made elliptically. In other words, the connection 17 has the shape of an ellipse.
• the ratio between the small radius and the large radius of the elliptically shaped connection 17 between the inlet pipe 120 and the cylindrical portion 110 is between 1 and 2.
• the upper contour 112 of the cylindrical portion 110 of the inner cavity 11 extends helically with a direction of winding identical to the direction of circulation of the liquid inside the inner cavity 11, and preferably from the top 171 down to the bottom 172 of the elliptical shaped connection 17 between the inlet pipe 120 and the cylindrical portion 110.
• the hydrocyclone comprises an underflow outlet 13 for discharging the solids essentially separated from the liquid of the mixture introduced into the hydrocyclone via the inlet pipe 120.
• This underflow 13 communicates with the lower end of the inner cavity 11, plus precisely with the lower end of the frustoconical portion 111.
• the underflow outlet 13 extends from the lower end of the lower portion of frustoconical section 111. It has a frustoconical section 130 whose diameter increases towards the lower part of the hydrocyclone.
• This frustoconical portion is in this embodiment the trunk of a cone of revolution. It opens out of the body 10.
• the length L of the underflow 13 is greater than three times the diameter of the junction between the frustoconical lower portion of the inner cavity and the underflow outlet of the hydrocyclone.
• the angle ⁇ of the frustoconical section 130 of the underflow 13 with respect to its longitudinal or revolving axis is between 10 and 25 °.
• the underflow 13 comprises at least one helical groove 14 whose winding direction is identical to the direction of circulation of the liquid inside the inner cavity 11, that is to say the liquid mixture composed of solids and liquid which is introduced inside the hydrocyclone.
• the number of grooves will preferably be even. It may for example be equal to two or four.
• the grooves will be uniformly distributed at the periphery of the frustoconical section 130 of the underflow 13.
• the groove or grooves will preferably be hollowed out on the surface of the frustoconical section 130 of the underflow 13. Alternatively, they may protrude on the surface of the frustoconical section of the underflow, that is to say forming an extra thickness inside the underflow 13.
• the groove or grooves 14 extend in part over the contour of the lower portion of the inner cavity.
• the hydrocyclone comprises an overflow outlet 15 for discharging the liquid essentially separated from the solids of the mixture introduced into the hydrocyclone via the inlet manifold.
• This overflow communicates with the upper end of the inner cavity 11, more precisely with the upper end of the cylindrical upper portion 110.
• the overflow outlet 15 comprises a frustoconical pipe 151 which extends in the extension of the cylindrical portion 110. Its diameter increases. towards the upper part of the hydrocyclone. In this embodiment, it constitutes the trunk of a cone of revolution.
• the frustoconical tubing 151 of the overflow 15 comprises an inlet 1510 which communicates with the internal cavity 11, in this case with its cylindrical upper portion 110, and an outlet 1511 which opens into a peripheral recess 16 formed in the body 10.
• This housing device is a collection box.
• the overflow 15 further comprises a discharge pipe 152 which extends laterally to the body 10 along an axis substantially orthogonal to the longitudinal axis of the body 10.
• This lateral evacuation pipe 152 comprises an inlet 1521 which communicates with the housing 16 and an outlet 1522 which opens out of the body 10.
• the overflow 15 is an overflow overflow to the extent that the liquid from the frustoconical pipe 151 overflows into the peripheral housing 16 and flows into the discharge pipe 152 .
• the angle of the frustoconical tubing 151 of the overflow relative to its longitudinal or revolving axis is between 10 and 30 °.
• the hydrocyclone comprises means for injecting operating water into the internal cavity, at the junction between the frustoconical lower portion and the underflow.
• injection means may for example comprise a service water injection pipe 60.
• a hydrocyclone according to the invention can conventionally be used to carry out the separation of a liquid phase and a solid phase from a mixture, such as for example a mixture of water and sludge containing ballast. .
• a mixture such as for example a mixture of water and sludge containing ballast.
• such a mixture is introduced inside the hydrocyclone via the inlet pipe 120 at a low pressure preferably between 0.3 and 1.5 bar.
• the inlet manifold is inclined towards the underflow of the hydrocyclone.
• the fluid is thus oriented as it enters the hydrocyclone in the direction of its flow inside the inner cavity 11 of the hydrocyclone. This further reduces the supply pressure by avoiding the "dead volume" at the top of the internal cavity that traps solid and adversely affect the quality of the separation.
• the fluid enters the interior of the cylindrical upper portion 110 through the elliptical shaped connection between the inlet manifold 120 and the cylindrical upper section.
• this connection is made tangentially to the inner peripheral contour of the upper cylindrical portion 110. Because of the geometric characteristics of this connection, the solids and the liquid remain plated near the inner wall of the inner cavity 11 as soon as they entry into it.
• the fluid flows along the upper contour 112 of the cylindrical portion 110 of the inner cavity 11 which extends helically with a direction of winding identical to the direction of flow of the liquid inside the inner cavity 11 from the top to the bottom of the elliptical shaped connection between the inlet pipe 120 and the cylindrical portion 110. This makes it possible to avoid the dead zones in the upper region of the cylindrical upper portion 110, to cause the fluid to flow towards the underflow of the hydrocyclone and to reduce the supply pressure.
• the fluid continues to flow inside the inner cavity 11 passing through the frustoconical lower portion 111.
• the solid phase then flows to the underflow 13 of the hydrocyclone while the liquid phase rises to the overflow 15 of the hydrocyclone.
• the solid phase flows from the frustoconical lower section 111 towards the underflow 13. It then flows along the grooves 14 which extend over the peripheral contour of the lower region of the frustoconical section 111.
• the implementation of the grooves 14 in this zone makes it possible to maintain the rotation of the fluid and to reduce the sensitivity of the hydrocyclone to the load in MES of the mixture introduced into it.
• the solid part of the fluid flows inside the frustoconical section 130 of the underflow 13.
• the implementation of a frustoconical section underflow whose diameter widens downwards makes it possible to avoid the induced flows therefrom. which makes it possible to maintain the rotation of the fluid inside the hydrocyclone. This reduces the supply pressure.
• Grooving 14 inside the frusto-conical section 130 makes it possible to maintain the rotation of the fluid and consequently to make the hydrocyclone less sensitive to the change in the charge in MES of the mixture introduced into it.
• the liquid phase rises inside the interior cavity 11, passing from the frustoconical lower portion 111 to the cylindrical upper portion 110 and then to the frustoconical tubing 151 of the overflow 15.
• the implementation of the frustoconical tubing 151 whose diameter widens upwards keeps the anisotropy of the flow overflow. This keeps the rotation of the fluid. This also reduces the supply pressure.
• the liquid then overflows from the upper part of the frustoconical pipe 151 inside the peripheral housing 16. It then flows from the peripheral housing 16 inside the evacuation pipe 152.
• the technique according to the invention makes it possible to facilitate the rotation of the fluid inside the hydrocyclone and to maintain this rotation by the implementation, independently or in combination:
• the technique according to the invention makes it possible to reduce the supply pressure of the hydrocyclone by the implementation, independently or in combination: of the spiral-shaped inlet pipe;
• the technique according to the invention makes it possible to reduce the sensitivity of the hydrocyclone to the variations in MES charge of the mixture introduced inside thereof and thus to limit the phenomenon of bottlenecks of the underflow, by the implementation of , independently or in combination:

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• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Cyclones (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Agricultural Chemicals And Associated Chemicals (AREA)
• Glanulating (AREA)

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• 2014
  • 2014-11-28 FR FR1461630A patent/FR3029192A1/fr active Pending
• 2015
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  • 2015-11-27 KR KR1020177014427A patent/KR20170087894A/ko unknown
  • 2015-11-27 US US15/531,023 patent/US20170312764A1/en not_active Abandoned
  • 2015-11-27 WO PCT/EP2015/077967 patent/WO2016083603A1/fr active Application Filing
  • 2015-11-27 UA UAA201705165A patent/UA117073C2/uk unknown
  • 2015-11-27 CN CN201580071247.5A patent/CN107107077A/zh active Pending
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  • 2015-11-27 AU AU2015352424A patent/AU2015352424A1/en not_active Abandoned
  • 2015-11-27 EP EP15805419.7A patent/EP3223957A1/fr not_active Withdrawn
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  • 2015-11-27 CA CA2967535A patent/CA2967535A1/fr not_active Abandoned
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• 2017
  • 2017-05-10 ZA ZA2017/03235A patent/ZA201703235B/en unknown

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