USRE44213E1 - Centrifugal separator for mixtures in a liquid or gaseous medium - Google Patents
Centrifugal separator for mixtures in a liquid or gaseous medium Download PDFInfo
- Publication number
- USRE44213E1 USRE44213E1 US13/417,160 US200413417160A USRE44213E US RE44213 E1 USRE44213 E1 US RE44213E1 US 200413417160 A US200413417160 A US 200413417160A US RE44213 E USRE44213 E US RE44213E
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- chamber
- outlet
- inlet
- separation
- vanes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D45/00—Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces
- B01D45/12—Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces by centrifugal forces
- B01D45/14—Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces by centrifugal forces generated by rotating vanes, discs, drums or brushes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
- B01D17/02—Separation of non-miscible liquids
- B01D17/0208—Separation of non-miscible liquids by sedimentation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
- B01D17/02—Separation of non-miscible liquids
- B01D17/0217—Separation of non-miscible liquids by centrifugal force
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/02—Settling tanks with single outlets for the separated liquid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/24—Feed or discharge mechanisms for settling tanks
- B01D21/2405—Feed mechanisms for settling tanks
- B01D21/2411—Feed mechanisms for settling tanks having a tangential inlet
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/26—Separation of sediment aided by centrifugal force or centripetal force
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/26—Separation of sediment aided by centrifugal force or centripetal force
- B01D21/262—Separation of sediment aided by centrifugal force or centripetal force by using a centrifuge
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/2931—Diverse fluid containing pressure systems
- Y10T137/3003—Fluid separating traps or vents
- Y10T137/3009—Plural discriminating outlets for diverse fluids
Definitions
- the purpose of the invention is the separation, from a continuously flowing fluid mixture, of any components that have a greater density or molecular mass than that of the medium itself.
- the method makes use of centrifugal force to achieve this, it can be classified in the category of centrifugal separators.
- the centrifugal separators appertaining to the current state of the art are essentially formed by a cylindrical chamber which rotates at high speed. It is into this chamber that the fluid mixture to be treated enters. The fluid is rotated along with the chamber and thus, due to centrifugal force, the higher density components accumulate on the inner walls of the cylinder, whereas the liquid medium, at lower density, comes out of the cylinder.
- a cochlea is used to push the accumulated material out of the centrifugation chamber. Alternatively, it is necessary to interrupt the rotation in order to empty the separator. These types of centrifugal separators cannot be used on mixtures in a gaseous medium.
- separators for oleaginous mists that are equipped with a porous filter which rotates in a chamber.
- This type of separator only uses centrifugal force to project the oil, which condenses on passing through the micro-channels, against the inner wall of the chamber.
- the use of this type of separator is necessarily limited to mists.
- the document entitled DE 100 35 055 A1 (INNOVA ENTWICKLUNGS) describes a separator which has an annular separation chamber.
- the document entitled WO 2004/050255 A2 describes a gas separator.
- FIGS. 1 and 3 The axonometric figures are, in relation to FIGS. 1 and 3 , at a slightly reduced scale ( ⁇ 10.14%), except FIG. 9 which is slightly enlarged (+6.53%).
- FIG. 1 A first figure.
- a longitudinal section of the separator is depicted in this figure with full labeling and numbering of all the components, with the exception of the outlet chamber ( 32 ).
- This figure shows a detail of separator by which the outlet manifold ( 7 ) is pointed out with its components (bell cap ( 25 ), support ( 26 ), and vanes ( 24 )) and the almost virtual space (outlet chamber ( 32 )) which separates it from the rotor ( 2 ).
- This figure depicts a longitudinal section of the separator with a reproduction of it in operation.
- This figure depicts the schematics of a longitudinal section of the separator at a much reduced scale.
- the numbered parts in black represent the components with rotatory movement.
- This figure shows an isometric orthogonal axonometric view from below with a longitudinal section of the housing ( 1 ).
- This figure shows the same view as FIG. 5 , but also includes the longitudinal section of the upper cover plate ( 28 ), of the inlet axial tube ( 11 ) and a hemi section of the grill ( 34 ). Some of the inlet vanes have been removed in order to convey their relationship more clearly.
- This figure shows an isometric orthogonal axonometric view from below with a longitudinal section of the housing ( 1 ), of the lower cover plate ( 29 ) and of the outlet manifold ( 7 ) in order to show empty and visible one half of the outlet chamber ( 32 ).
- FIG. 7 This figure shows the same view as FIG. 7 , but also with a longitudinal section of the outlet axial tube ( 12 ) and of a gear ( 19 ); without the longitudinal section of the outlet manifold ( 7 ) except for its support ( 26 ). There is also a hemi section of the grill ( 34 ) and some separation vanes ( 36 ) have been removed in order to represent their relationship more clearly.
- This figure shows an axonometric view of the grill ( 34 ).
- This figure illustrates the separator without the grill ( 34 ) and the outlet pump ( 8 ).
- This separator can be used for fluid mixtures both in a liquid medium as well as in a gaseous medium. It is made up of several components, some of which need not be utilized depending on the case in hand (particularly when used on mixtures in a gaseous medium).
- the separator is composed of the following structures:
- the outlet manifold ( 7 ) comprises:
- ROTOR ( 2 ) which is composed of the following:
- the inlet chamber ( 30 ) comprises:
- the separation chamber ( 31 ) comprises:
- the diaphragm chamber ( 33 ) comprises:
- the grill ( 34 ) comprises:
- CONTROL SYSTEM ( 3 ), which comprises the following:
- This is a closed structure which, externally, can have various shapes. However, for the sake of clarity of description we will consider it cylindrical.
- the inflow and outflow of the separator are ensured by the inlet pipe ( 4 ) and the discharge pipe ( 5 ).
- One of these is mounted eccentrically on one of the flat surfaces; the other is also fixed eccentrically on the opposite surface. They communicate with the inlet manifold ( 6 ) and the discharge pump capsule ( 8 ) respectively, which becomes a discharge manifold ( 8 bis) for gaseous mixtures.
- the inlet manifold ( 6 ) continues along a short inlet axial tube, ( 11 ) around which the rotor ( 2 ) revolves.
- the flat surface where the inlet pipe ( 4 ) is fixed, houses a watertight ball bearing ( 14 ) for the mechanical driving shaft ( 15 ) of the rotor ( 2 ).
- the outlet manifold ( 7 ) is composed of a certain number of vanes ( 24 ) mounted radially on a support ( 26 ) in the shape of a circular crown.
- Their axis is perpendicular to that of the rotation of the rotor ( 2 ) and inclined backwards in relation to the direction of the rotation. As such, this axis forms a certain angle, with an ideal radius passing through the innermost extremity.
- the vanes are slightly curved with an anterior convexity.
- the outlet manifold ( 7 ) is housed in the outlet chamber ( 32 ) of the rotor ( 2 ).
- the rotor ( 2 ) revolves around the outlet manifold ( 7 ) and the outlet axial tube ( 12 ).
- the outlet axial tube ( 12 ) connects the outlet manifold ( 7 ) to the capsule of the discharge pump ( 8 ) or the discharge manifold ( 8 b) (if the pump ( 8 ) is not used).
- the discharge pump ( 8 ) is a centrifugal pump which is housed at the end of the outlet axial tube ( 12 ) in the wall where the discharge pipe ( 5 ) is mounted. It is activated by a joint with a hinge pin ( 9 ) which passes through two watertight ball bearings ( 10 ). By means of an appropriate transmission connection, the traction may depend on either the motor of the separator itself or an independent one.
- This chamber ( 13 ) communicates, directly, only with the collection cells ( 41 ) of the grill ( 34 ) via the apertures ( 42 ), and from there with the separation chamber ( 31 ) of the rotor ( 2 ). In the case that the grill ( 34 ) is not used, the chamber ( 13 ) communicates directly with the separation chamber ( 31 ).
- an opening for an electromagnetic valve ( 46 ) which connects to the exterior and a second opening for an electromagnetic valve ( 45 ) which communicates with a compressor (not depicted in the drawings).
- a third electromagnetic valve ( 47 ) positioned close to the bottom is designed for liquids and connect the accumulation chamber ( 13 ) with a reservoir (not depicted in the drawings).
- the discharge pump ( 8 ) is, in practice, unnecessary when the separator is being used on gaseous fluids.
- This chamber is truncated cone- (or cup-) shaped with the large base directed upwards. The outside edge is cut vertically thus forming an opening at the belt.
- the chamber ( 30 ) is enclosed below by the upper wall ( 38 ) of the diaphragm chamber ( 33 ) and above by the upper cover plate ( 28 ).
- the inlet axial tube ( 11 ) houses the inlet axial tube ( 11 ) around which the cover plate ( 28 ) (which is fixed to the rotor ( 2 )) revolves. This moving joint is watertight.
- the inlet axial tube ( 11 ) connects the inlet chamber ( 30 ) to the inlet manifold ( 6 ).
- the external surface at the belt of the inlet chamber ( 30 ) is open so that it communicates with the separation chamber ( 31 ).
- the cross-section dimension (the opening) of the inlet tube ( 11 ) and the cross-section of the belt opening mentioned above must correspond.
- this chamber ( 30 ) there are a number of vanes ( 35 ) arranged radially and inclined in the same way as the vanes ( 24 ) of the outlet manifold ( 7 ). They are slightly curved with the concavity at the front. Their upper and lower edges are attached to the upper cover plate ( 28 ) and the upper wall ( 38 ) of the diaphragm chamber ( 33 ) respectively. Their internal extremity is positioned slightly outside the central aperture, that external where the separation chamber ( 31 ) begins.
- Both diameters of the crown are the same along the entire chamber ( 31 ).
- the separation chamber ( 31 ) houses a certain number of rectangular (or quadrangular) separation vanes ( 36 ). These are arranged radially at regular intervals, with one axis parallel to that of the rotation of the rotor and the other perpendicular to the axis of rotation and inclined backwards in relation to the direction of rotation, forming an angle of around 45-60° with the ray of the rotation plane.
- the vanes are slightly curved on the axis that is perpendicular to that of the rotation, with the convexity orientated to the front, with an angle of around 20° at the centre.
- the edges of the separation vanes ( 36 ) are attached on top to the upper cover plate ( 28 ) and below to the lower cover plate ( 29 ). Internally they are attached to the tubular wall ( 40 ) of the diaphragm chamber ( 33 ). As we have already mentioned, externally they are covered, above and below, by the upper ( 28 ) and lower cover plates ( 29 ) on the segments corresponding to the communication window with the inlet ( 30 ) and outlet chambers ( 32 ). The part that remains or continues along the longitudinal walls of the collection cells ( 41 ) of the grill ( 34 ) is exposed if it is not used.
- the number of vanes mounted must be compatible with the coarseness of the components of the fluid mixture, which can enable a clogging of the space between them.
- the number of vanes used may vary depending on the characteristics of the components to be extracted from the fluid as well as the viscosity of the medium, from between approximately 8 and 380.
- the outlet manifold ( 7 ) is housed in this chamber ( 32 ). This manifold ( 7 ) continues by the outlet axial tube ( 12 ). The space between the outlet manifold ( 7 ) and the walls of the outlet chamber ( 32 ) is almost non-existent. The rotor ( 2 ) can rotate around it without any friction.
- tubular wall ( 40 ) also constitutes the inner wall of the separation chamber ( 31 ).
- the upper ( 38 ) and lower ( 39 ) walls also constitute the lower wall of the inlet chamber ( 30 ) and the upper wall of the outlet chamber ( 32 ).
- the height of the truncated cones will depend on the necessary inlet and outlet flow rates.
- the chamber ( 33 ) is completely closed. At the center of the lower wall, on the upper slope, there is a watertight ball bearing ( 37 ) mounted. This is penetrated by the pivot ( 27 ) of the bell cap ( 25 ) of the outlet manifold ( 7 ) via an aperture.
- the channels Embedded in its wall are the channels, whose direction is parallel to that of the axis of rotation.
- the channels continue towards the exterior, positioned between the separation vanes ( 36 ).
- Their lateral and longitudinal walls are a continuation of the separation vanes ( 36 ).
- These channels are shaped in such a way that their cross-section is a semi-circle or a semi-ellipse or a circular arc and positioned with the curved slope towards the exterior.
- the interior slope of the channels is completely exposed, connecting the channels formed by the separation vanes ( 36 ) to the channels of the grill ( 34 ).
- each cell ( 41 ) is completely exposed in cases where gaseous fluids are used, or are pierced by circular apertures ( 42 ) when liquid fluids are used.
- These circular apertures ( 42 ) must not have a diameter that exceeds the limit determined in proportion to the surface tension of the liquid medium and the total density of the mixture. For low total densities of the mixture, if the medium is water, this diameter should not be greater than approximately 8 mm.
- the passage from the cell ( 41 ) cavity to the aperture ( 42 ) should be rounded in order to avoid obstruction of the sliding of the compacted particles.
- the outer wall of the grill ( 34 ) preferably has a polygonal cross-section, with the same number of sides as that of the grill channels (and the number of rows of the collection cells ( 41 )).
- the outlet of the apertures ( 42 ) is a flat surface.
- the grill ( 34 ) is enclosed above by the upper cover plate ( 28 ) and below by the lower cover plate ( 29 ).
- This thin structure covers the inlet chamber ( 30 ) and the separation chamber from above, without any continuation solution and in a watertight fashion, in following the separation chamber ( 31 ) on the external surface at belt, in level of communication with the inlet chamber ( 30 ). Furthermore, it closes off the grill ( 34 ) from above.
- the inlet axial tube ( 11 ) penetrates the cover plate's central aperture which, if possible, is equipped with a gasket made out of appropriate material.
- this is identical to the upper cover plate ( 28 ) except for the fact that it covers the outlet chamber ( 32 ), the separation chamber ( 31 ) and the grill ( 34 ) from below; the part at belt which covers the outer wall of the separation chamber, if necessary, is shorter.
- the outlet axial tube ( 12 ) penetrates the cover plate's central aperture which, is possibly equipped with a gasket made out of appropriate material.
- the central apertures of these two cover plates ( 28 ) ( 29 ) allow these, along with the rotor ( 2 ) to which they are fastened, to rotate around the two axial tubes ( 11 ) ( 12 ), which are immobile.
- Utility of the control system can be limited, especially when using mixtures in a gaseous medium. It is composed of: an electro mechanical inlet diaphragm ( 43 ) (or a mechanical inlet valve), and electro mechanical outlet diaphragm ( 44 ) (or a pressure valve with adjustable aperture, in the case of liquid fluids, or a common mechanical outlet valve if the mixture is in a gaseous medium), a pressure sensor ( 48 ), a liquid level sensor ( 49 ), three electromagnetic valves ( 45 )( 46 )( 47 ), a gas compressor ( 51 ) (not depicted), an electronic control circuit ( 50 ) (not depicted), a reservoir ( 52 ) (not depicted). When using mixtures in a gaseous medium, the compressor and its electromagnetic valve may not be used ( 45 ).
- the electro mechanical inlet diaphragm (or the mechanical inlet valve) is housed upstream of the inlet manifold ( 6 ).
- the electro mechanical outlet diaphragm ( 43 ) (or the outlet valve) is inserted downstream of the discharge pump ( 8 ) or, in its absence, downstream of the discharge manifold ( 8 b).
- the electro mechanical diaphragm is essentially comprised of a swivelling disk about a medial axis. With the help of a spring and the re-entry of a special closeout mechanism, the disk is positioned parallel to the flux, thus allowing it to flow uninhibited. A small electric motor allows the return to the closeout position.
- the outlet valve When using liquid mixtures, the outlet valve must have an adjustable aperture pressure.
- Two of the three electromagnetic valves ( 45 ) ( 46 ) ( 47 ) are designed for gas ( 45 ) ( 46 ) and are fitted in the wall of the accumulation chamber ( 13 ), towards the top. One ( 45 ) of these communicates with the gas compressor, the other ( 46 ) with the outside.
- the third ( 47 ) is designed for dense liquids and is housed in the wall of the accumulation chamber ( 13 ), towards the bottom. It connects the accumulation chamber ( 13 ) with a reservoir (not depicted in the diagrams). If necessary, an axial pump can be used to aid the flow of very dense liquids. If needed, a turbidimeter and a densimeter can also be used.
- the inlet vanes ( 35 ) rotate thus producing the centrifugal force necessary for the propulsion of the fluid. Due to this propelling force, the fluid passes into the separation chamber ( 31 ). If the separator is fed by a pump or if there is an upstream external force, these two forces will naturally add to the propulsion. It is possible to limit the flow rate by restricting the aperture of the electro mechanical inlet diaphragm ( 43 ) or by means of an inlet tap.
- This movement of the fluid in the case of mixtures in a liquid medium, must be limited to avoid the flooding of the accumulation chamber ( 13 ) and, as a result, causing a reduction in the angular velocity of the swiveling of the rotor.
- This phenomenon can be avoided by a preemptive gaseous pressure in the accumulation chamber ( 13 ) generated by a compressor that is activated by the electronic circuit of the control system ( 3 ). This pressure would be equal to the addition of the centrifugal force, which propels the fluid into the accumulation chamber ( 13 ), together with the pressure that derives from the resistance to the flow of the fluid towards the exterior of the separator.
- outlet pump ( 8 ) neutralizes the resistance of the flow of the fluid towards the exterior of the separator by means of discharge. Furthermore, through appropriate regulation, it will neutralize the pressure gradient generated by the force of gravity between the top and bottom of the chamber ( 31 ).
- the pressure that propels the fluid from the separation chamber ( 31 ) to the accumulation chamber ( 13 ) will depend solely on the centrifugal force generated in the separation chamber ( 31 ).
- the use of this pump ( 8 ) for mixtures in a gaseous medium is relative.
- the problem of flooding the accumulation chamber ( 13 ) does not exist for mixtures in a gaseous medium.
- the presence of the grill ( 34 ) is essential for mixtures in a liquid medium in order to avoid that the air compressed in the accumulation chamber ( 13 ) forces the outer stratum of the liquid present in the separation chamber ( 31 ), and that by penetrating the strata of the lower pressure liquids, escape from the accumulation chamber which would be flooded by the liquid.
- the transversal subdivision of the channels of the grill into collection cells ( 41 ) will limit any turbulence caused by the friction between the fluid that flows along the separation chamber, ( 31 ) and that which is in the grill ( 34 ) being more or less immobile.
- the grill ( 34 ) will also eliminate any friction between the fluid in the separation chamber ( 31 ) and the fluid in the accumulation chamber ( 13 ), thus reducing any resulting turbulence. Turbulence can cause the re-entry of high density components into the separation chamber ( 31 ), especially in the case of separation chambers ( 31 ) with a very small “critical space” (the difference between the internal and external radii). Therefore, due to the turbulence limitation, the grill ( 34 ) is both useful for liquid and gaseous fluids.
- the collection cells ( 41 ) also allow the denser components to accumulate. As such they form a body with an increased mass which, propelled by a sufficiently high centrifugal force, can be expelled into the accumulation chamber ( 13 ).
- the gas that is present between the separation vanes ( 36 ) is propelled towards the accumulation chamber ( 13 ).
- the gaseous pressure will be lower in these areas than in the accumulation chamber ( 13 ).
- the mixture will be propelled towards the outlet of the separation chamber ( 31 ).
- the closure of the electro mechanical diaphragm ( 44 ) until the fluid arrives at the threshold of the outlet manifold ( 7 ) is essential for liquid fluids.
- the reason for this is to avoid the air that has been compressed in the accumulation chamber from escaping through the outlet manifold ( 7 ) to the exterior, thus allowing the fluid to flood into the accumulation chamber ( 13 ) and prevent or inhibit the swiveling of the rotor ( 2 ) due to its viscosity. This problem does not occur for mixtures in a gaseous medium.
- the closure of the inlet diaphragm ( 43 ) prevents the gas that has been compressed in the accumulation chamber ( 13 ) from rising back along the entry channels at the end of the cycle and thus allowing a penetration of the liquid (when using liquid mediums) into the accumulation chamber ( 13 ).
- the closure of the discharge downstream of the separation chamber ( 31 ) at the end of the cycle prevents the gas that is compressed in the accumulation chamber ( 13 ) from escaping from the chamber ( 13 ) to the exterior of the separator.
- the closure of the two diaphragms ( 43 ) ( 44 ) or the two valves prevents the dispersion of particles to the exterior.
- the discharge pump ( 8 ) useful for mixtures in liquid mediums, prevents the generation of a pressure gradient (no matter how small) between the initial part of the separation chamber ( 31 ) and the end of the chamber.
- control system ( 3 ) By means of the control system ( 3 ) it is possible to prevent the liquid medium of the mixture from invading the accumulation chamber ( 13 ) and, as a result, it is possible for the rotor ( 2 ) to pivot unobstructed, even at a very high velocity.
- the system ( 3 ), with the help of the compressor ( 51 ), enables the compensation of any possible minimal losses of air from the accumulation chamber ( 13 ) through the watertight pivoting joints.
- the control system ( 3 ) triggers a gas discharge, thus redirecting the pressure to the necessary levels to avoid the entry of the (liquid) medium into the accumulation chamber ( 13 ), whilst not inhibiting the expulsion of the denser components.
- the system triggers its release into a reservoir.
- this system ( 3 ) allows the regulation of the pressure in the accumulation chamber ( 13 ) in such a way as to counteract, through an increase or decrease in the force applied, the expulsion of aggregates out of the cells, ( 41 ) thus obtaining an extraction material that is more or less dense.
- the fluid is distributed between the inlet vanes ( 35 ).
- the higher density components offer greater resistance to acceleration, they will move in a relative motion in comparison to their fluid medium and, particularly if the space between the inlet vanes ( 35 ) is sufficiently limited, this will cause a compacting of the higher density components against the vane that follows them in the rotational motion.
- a thin layer of the higher density material will form along the vane and will progressively increase in mass whilst the penetration front will be reduced.
- the mass increases the centrifugal force.
- a small penetration front allows velocity of movement through the fluid medium. This compacting phenomenon will therefore assist the movement of the higher density components from the separation chamber ( 31 ) to the accumulation chamber, ( 13 ) and subsequently their expulsion.
- the fluid that has been modified by this process then enters into the separation chamber ( 31 ).
- the centrifugal force in the separation chamber ( 31 ) propels the higher density components directly into the accumulation chamber ( 13 ). If, however, the grill ( 34 ) is used, the centrifugal force forces them into the collection cells ( 41 ) of the grill, ( 34 ) and from there towards the accumulation chamber ( 13 ). The distance that these components have to travel is equal to the difference between large and small radii of the separation chamber ( 31 ). We have named this distance as the “critical space”. This movement is limited by the viscosity of the fluid medium and is aided, as we have already mentioned, by a high mass-advancement front ratio of the high density body.
- the separation chamber ( 31 ) with a circular crown cross-section has the advantage over a cylindrical chamber of having a “critical space” which can be very small, even down to the micrometer. It is also possible to achieve the desired flow rate by means of an equal and congruous increase in the two radii.
- critical space we mean the distance that the body to be separated from the fluid medium must travel in order to emerge from the flux that would otherwise transport it, unseparated, outside the separator. As we have discussed, in the case of this apparatus, the “critical space” is the difference between the external and internal radii of the circular crown section of the separation chamber ( 31 ).
- This type of separation chamber ( 31 ) allows for a very large rotation radius without the need for a proportional increase in the “critical space” and, as a result, it also enables a proportionally high centrifugal force. In spite of high angular velocities, the thickness of the fluid for being limited, also the pressure derived from the centrifugal force will be limited. Thanks to this, watertightness of the pivoting joints will be adequate.
- C) The extraction and thus the definitive separation of the higher density components is not entrusted to a cochlea. Instead it occurs directly via the expulsion of the components into the accumulation chamber.
- the grill limits turbulence in the case of mixtures in both a liquid and gaseous mediums.
- the inlet vanes ( 35 ) not only initiate propulsion but also modify the distribution of the components of the mixture through concentrating the higher density components and forming a layer of increased mass and smaller penetration front, which can then be expelled more rapidly.
- the flow rate of the fluid to be treated is the flow rate of the fluid to be treated.
- the density of the components to be extracted is the density of the components to be extracted.
- the critical space is the difference between the external and internal radii of the separation chamber ( 31 ).
- This space can be very small and, in order to maintain the necessary flow rate, it is possible to increase the two radii of the separation chamber ( 31 ).
- the useful length of the separation chamber ( 31 ) represented by the length of the part of the external surface of the separation chamber ( 31 ) that is not covered by the two cover plates ( 28 ) ( 29 ).
- the centrifugal vector is, on scalar value, proportional to the mass (and thus to the product of the density by the volume or, in the case of substances in a solution or gas, to the molecular mass).
- the velocity at which the higher density components move towards the collection cells ( 41 ) must be sufficient to reach them before arrival at the point where the fluid begins to deviate on entering the outlet manifold ( 7 ). At this point the thrust vector begins to oppose the centrifugal force and can therefore reduce or even neutralize it. Due to this fact, the utility of a separation chamber ( 31 ) with a sufficiently large cross-section has a limited critical space and a suitable length. This allows a reduction in the flow velocity in this sector and a transit to the collection cells as rapidly as possible, having a sufficiently long available time.
- R is the external radius of the separation chamber Recs and A is the cross section of the separation chamber Acs.
- ⁇ R is the critical space.
- m is the mass of the revolving body onto which the centrifugal force is applied
- R is the radius of the rotation plane around which the body turns
- T is the rotation period.
- V(cm/s) ( ⁇ 2 *r 2 * ⁇ *RM*tm 2 )/(4050* ⁇ )
- V is the velocity of a spherical particle with a radius r and mass m that moves through a medium with a coefficient of viscosity p towards the exterior of a separation chamber with a mean radius RM.
- This chamber pivots with a rotation frequency tm (revs per minute).
- vanes ( 36 ) the purpose of these vanes ( 36 ) is to guarantee that the angular velocity of the fluid is the same as that of the rotor ( 2 ) and that all the strata of the fluid from the exterior to the interior have the same angular velocity. Furthermore, the compacting process that begins between the inlet vanes ( 35 ) is continued between the vanes of the separation chamber ( 36 ).
- the number of separation vanes ( 36 ) used is sufficiently high in number and equal to that of the inlet vanes ( 35 ) and that of the longitudinal rows of the cells ( 41 ) of the grill ( 34 ). In cases where the grill ( 34 ) is not used, it is necessary to take into account the following considerations:
- the propulsion vector which is perpendicular to the radius of the rotation plane and produced by the inner-most part of a vane, must be in the direction of the external edge of the vane that precedes it in the rotational direction.
- the fluid is gaseous, and given that a gaseous fluid is compressible, it is important that the direction of the thrust vector passes through a point on the vane that, for the same radius, is more internal than bigger the angular velocity.
- the vanes ( 36 ) must be inclined in such a way that their transversal axis forms an angle of 45-60 degrees with the radius that passes through their interior edge.
- the vanes will preferably be curved on the transversal axis (with an angle at the centre of approximately 20°) with the convexity at the front.
- This force will depend on the specific friction coefficient and the angle between the force of reaction to acceleration and the transversal axis of the vane. It will be useful then, to use a material with a small friction coefficient for the separation ( 36 ) and inlet vanes ( 35 ).
- a slight anterior concavity curvature can be useful to slow the sliding of the higher density particles and therefore assisting their compaction.
- the inlet vanes ( 35 ) will end where the separation vanes begin ( 36 ) so that the aggregates can slide from the anterior surface of the inlet vanes to that of the separation vanes.
- This separator can be used for the separation, in continuous flow of mixtures in a liquid medium, therefore for all current uses of centrifugal separators, which is made currently:
- Industrial, civil and laboratory purification processes e.g.: sewage water and industrial discharge purification, or for producing drinking water. Extraction procedures in a variety of sectors (chemical, food, industrial etc).
- this separator can also be used on mixtures in a gaseous medium, even if they flow at high velocities, it lends itself to several possible uses: vacuum cleaners, air purifiers, purifiers from fumes and gases, purifiers for exhaust fumes and gases, civil, industrial and automotive uses.
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Abstract
Description
- 1) Housing
- 2) Rotor
- 3) Control system
- 4) Inlet pipe
- 5) Discharge pipe
- 6) Inlet manifold
- 7) Outlet manifold
- 8) Discharge pump (superfluous when used for mixtures in a gaseous medium, except for the capsule which is substituted by a discharge manifold (8 b))
- 9) Joint with hinge pin (superfluous when used for mixtures in a gaseous medium)
- 10) Ball bearings (superfluous when used for mixtures in a gaseous medium)
- 11) Inlet axial tube
- 12) Outlet axial tube
- 13) Accumulation chamber
- 14) Ball bearing
- 15) Driving shaft
- 16) Joint
- 17) Polishing blade
- 18) Shaft
- 19) Large cog wheel
- 20) Small cog wheel
- 21) Ball bearings
- 22) Pulley
- 23) Cap
- 24) Outlet vanes
- 25) Bell cap
- 26) Support
- 27) Pivot
- 28) Upper cover plate
- 29) Lower cover plate
- 30) Inlet chamber
- 31) Separation chamber
- 32) Outlet chamber
- 33) Diaphragm chamber
- 34) Grill (this is not necessarily essential especially when used for mixtures in a gaseous medium).
- 35) Inlet vanes
- 36) Separation vanes
- 37) Ball bearing
- 38) Upper wall
- 39) Lower wall
- 40) Tubular wall
- 41) Collection cells
- 42) Apertures
- 43) Electro mechanical inlet diaphragm (or a mechanical inlet valve)
- 44) Electro mechanical outlet diaphragm (or a mechanical outlet valve)
- 45) Electromagnetic valve for the compressor
- 46) Electromagnetic valve for gas discharge
- 47) Electromagnetic valve for liquid discharge
- 48) Pressure sensor
- 49) Liquid level sensor
- 50) Electronic control circuit (not depicted in the diagrams)
- 51) Gas compressor (not depicted in the diagrams)
- 52) Reservoir (not depicted in the diagrams)
(The numbers to the left of the components above correspond to those used in the drawings and are often used in the text to the right of the component name).
B) This type of separation chamber (31) allows for a very large rotation radius without the need for a proportional increase in the “critical space” and, as a result, it also enables a proportionally high centrifugal force. In spite of high angular velocities, the thickness of the fluid for being limited, also the pressure derived from the centrifugal force will be limited. Thanks to this, watertightness of the pivoting joints will be adequate.
C) The extraction and thus the definitive separation of the higher density components is not entrusted to a cochlea. Instead it occurs directly via the expulsion of the components into the accumulation chamber. This ensures that the higher density particles are separated from a gaseous medium prior to evacuating the separation chamber and as such it is possible to obtain a fluid medium that is completely devoid of these particles. This constitutes an important point of distinction from other centrifugal separators such as: DE 100 35 055 A1 (INNOVA ENTWICKLUNGS) or WO 2004/050255 A2 where there is no possibility of separating the solid (or semi-solid) particles from a fluid medium, and it is only possible to separate two fluids with differing densities. The solid particles that are separated off from a liquid medium in the above-mentioned patents are not able to run off as they would clog up the outlet channels. This would be the case for both gaseous and liquid mediums.
D) The rotation of the fluid does not rely on friction with the walls of the separation chamber. (31) Nor, as a consequence, is the rotation quicker for strata with more direct contact with the walls than those further away. The presence of the separation vanes (36) ensures a uniform application of force to all the strata of the fluid and, at the same time, they continue to compact the higher density components, therefore aiding their expulsion. The separation vanes (36) allow the use of the separator also on mixtures in a gaseous medium since they generate a uniform force and rotation in all strata.
E) The grill (34) also enables the use of this separator at very high angular velocities on mixtures in a liquid medium. Furthermore, the grill limits turbulence in the case of mixtures in both a liquid and gaseous mediums.
F) The inlet vanes (35) not only initiate propulsion but also modify the distribution of the components of the mixture through concentrating the higher density components and forming a layer of increased mass and smaller penetration front, which can then be expelled more rapidly.
G) As is the case with all centrifugal separators, but with the distinctive feature that this separator can also be used with mixtures in a gaseous medium, there is no need to change any filters.
qv/Acs=Vmcs
Lucs/Vmcs=Tu
V=Ec/Tu
R=[(ΔR2*π+A)/(ΔR*π)]/2
Fc=4*π2*m*R/T2
Where
m is the mass of the revolving body onto which the centrifugal force is applied,
R is the radius of the rotation plane around which the body turns,
and T is the rotation period.
V=F/(6*π*r*η)
V=[(4*π2*m*R)/T2]/(6*π*r*η)
where T is the period
T=1/ts
(ts=revs per second).
m=ρ*π*r3* 4/3
where ρ is the density of the particles.
V(cm/s)=(π2*r2*ρ*RM*tm2)/(4050*η)
where V is the velocity of a spherical particle with a radius r and mass m that moves through a medium with a coefficient of viscosity p towards the exterior of a separation chamber with a mean radius RM. This chamber pivots with a rotation frequency tm (revs per minute).
tm=√[(V*4050*η)/(π2*r2*ρ*RM)]
RM=(V*4050*η)/(π2*r2*ρ*tm2)
-
- When using fluids containing components that are extremely coarse, it will be necessary to triturate the components prior to introducing them into the separator.
- If the separator is used to extract the vapour from a fluid mixture in a gaseous medium at high temperatures (e.g. discharge gas derived from combustion); it will be necessary to refrigerate the fluid upstream of the separator in order to avoid any overheating. Such the vapour will be condensed so as to prevent it from returning to its original molecular form after its capture. Since it has a lower molecular mass than nitrogen, cannot be captured if some nitrogen or another higher density gas is present, even in conditions of extremely high angular velocity.
- For the extraction of very small (liquid or solid) particles mixed in with the gas, the separation can be assisted by enriching the gaseous mixture (smoke or mist), to be treated, with a liquid emulsion which, after having captured the particles, will be easier to extract.
- Through the above method, it is also possible to capture some gases that react selectively with the substances in solution in the emulsified liquid.
-
- It can be used for the purification from smoke, mists, dust, and for the separation of other contaminant particles from the air (bacteria, viruses, pollen, mites etc.).
- It can be used in the separation of components with differing density or molecular mass which form a gaseous mixture (gas/vapours, gases with differing molecular mass); industrial, laboratory and civil processes (e.g.: extraction or separation of the vapour from a gas/vapour mixture or of a heavy gas from contaminated air; dehumidification etc.)
- Its use can extend to the extraction of one gas mixed with another after the reaction of the gas with a substance in a pulverized or nebulized solution.
Claims (37)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/417,160 USRE44213E1 (en) | 2004-07-08 | 2004-07-08 | Centrifugal separator for mixtures in a liquid or gaseous medium |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/IT2004/000377 WO2006006186A1 (en) | 2004-07-08 | 2004-07-08 | Centrifugal separator for separating fluid mixtures in liquid or gas medium |
US13/417,160 USRE44213E1 (en) | 2004-07-08 | 2004-07-08 | Centrifugal separator for mixtures in a liquid or gaseous medium |
US11/630,286 US7905360B2 (en) | 2004-07-08 | 2004-07-08 | Centrifugal separator for mixtures in a liquid or gaseous medium |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11630286 Reissue | 2007-04-02 |
Publications (1)
Publication Number | Publication Date |
---|---|
USRE44213E1 true USRE44213E1 (en) | 2013-05-14 |
Family
ID=34958270
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/630,286 Ceased US7905360B2 (en) | 2004-07-08 | 2004-07-08 | Centrifugal separator for mixtures in a liquid or gaseous medium |
US13/417,160 Expired - Fee Related USRE44213E1 (en) | 2004-07-08 | 2004-07-08 | Centrifugal separator for mixtures in a liquid or gaseous medium |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/630,286 Ceased US7905360B2 (en) | 2004-07-08 | 2004-07-08 | Centrifugal separator for mixtures in a liquid or gaseous medium |
Country Status (6)
Country | Link |
---|---|
US (2) | US7905360B2 (en) |
EP (1) | EP1763402B1 (en) |
AT (1) | ATE535307T1 (en) |
CA (1) | CA2569784C (en) |
ES (1) | ES2376170T3 (en) |
WO (1) | WO2006006186A1 (en) |
Families Citing this family (21)
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US9194265B2 (en) | 2010-01-27 | 2015-11-24 | Cummins Filtration Ip, Inc. | Rotating separator with housing preventing separated liquid carryover |
US8893689B2 (en) | 2010-01-27 | 2014-11-25 | Cummins Filtration Ip, Inc. | Crankcase ventilation self-cleaning coalescer with intermittent rotation |
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US8940068B2 (en) | 2010-01-27 | 2015-01-27 | Cummins Filtration Ip Inc. | Magnetically driven rotating separator |
US8807097B2 (en) * | 2010-01-27 | 2014-08-19 | Cummins Filtration Ip Inc. | Closed crankcase ventilation system |
KR20140048872A (en) * | 2011-04-29 | 2014-04-24 | 덱스? 유에스에이, 엘엘씨 | Fan filter device |
CN102847616A (en) * | 2011-06-30 | 2013-01-02 | 蒋立峰 | Distributing device of piston-pusher centrifuge |
IN2014CN03311A (en) | 2011-11-04 | 2015-07-03 | Cummins Filtration Ip Inc | |
US9618013B2 (en) | 2013-07-17 | 2017-04-11 | Rotational Trompe Compressors, Llc | Centrifugal gas compressor method and system |
US9919243B2 (en) * | 2014-05-19 | 2018-03-20 | Carnot Compression, Llc | Method and system of compressing gas with flow restrictions |
US10668428B2 (en) | 2016-08-24 | 2020-06-02 | Honeywell International Inc. | Apparatus and methods for enhancing gas-liquid contact/separation |
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US11209023B2 (en) | 2017-02-10 | 2021-12-28 | Carnot Compression Inc. | Gas compressor with reduced energy loss |
SE544065C2 (en) * | 2019-03-05 | 2021-11-30 | 3Nine Ab | Method and apparatus for cleaning an air flow from particles |
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EP4021613A1 (en) | 2019-08-30 | 2022-07-06 | Paragon Space Development Corporation | Two-phase separator device for removing condensate or particulate from a gas stream |
CN110478947A (en) * | 2019-09-27 | 2019-11-22 | 铜川安泰再生资源回收利用有限公司 | A kind of rubbish from cooking oil liquid separator and separating technology |
CN113200506B (en) * | 2021-07-05 | 2021-08-27 | 南通市通州区袁灶燃气有限公司 | Underground oil storage equipment |
US11780744B2 (en) * | 2021-10-04 | 2023-10-10 | Desert Water LLC | Methods and apparatuses for distilling seawater and brine and removing salt |
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US3094828A (en) * | 1958-08-11 | 1963-06-25 | Sharples Corp | Centrifugal dust separator |
US3734401A (en) * | 1970-07-29 | 1973-05-22 | D Frewen | Centrifugal separator |
FR2535216A1 (en) * | 1982-11-03 | 1984-05-04 | Saget Pierre | Improved apparatus for the centrifugal separation of a mixture containing at least one gaseous phase in which the improvements stem from nonreturn of the heavy phase which has reached the periphery. |
EP0745418A1 (en) * | 1995-05-31 | 1996-12-04 | Stork Ketels B.V. | Purification unit comprising a group of rotational particle separators. |
DE10035055A1 (en) * | 2000-07-19 | 2002-01-31 | Innova Entwicklungs Gmbh | Component separating unit comprises rotor, rotor chamber, inlet and outlets, and partial chamber sections |
WO2004050255A2 (en) * | 2002-12-02 | 2004-06-17 | Rerum Cognitio Forschungszentrum Gmbh | Method for separating gas mixtures and a gas centrifuge for carrying out this method |
-
2004
- 2004-07-08 AT AT04745202T patent/ATE535307T1/en active
- 2004-07-08 ES ES04745202T patent/ES2376170T3/en not_active Expired - Lifetime
- 2004-07-08 CA CA 2569784 patent/CA2569784C/en not_active Expired - Fee Related
- 2004-07-08 EP EP20040745202 patent/EP1763402B1/en not_active Expired - Lifetime
- 2004-07-08 US US11/630,286 patent/US7905360B2/en not_active Ceased
- 2004-07-08 US US13/417,160 patent/USRE44213E1/en not_active Expired - Fee Related
- 2004-07-08 WO PCT/IT2004/000377 patent/WO2006006186A1/en active Application Filing
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US3094828A (en) * | 1958-08-11 | 1963-06-25 | Sharples Corp | Centrifugal dust separator |
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FR2535216A1 (en) * | 1982-11-03 | 1984-05-04 | Saget Pierre | Improved apparatus for the centrifugal separation of a mixture containing at least one gaseous phase in which the improvements stem from nonreturn of the heavy phase which has reached the periphery. |
EP0745418A1 (en) * | 1995-05-31 | 1996-12-04 | Stork Ketels B.V. | Purification unit comprising a group of rotational particle separators. |
DE10035055A1 (en) * | 2000-07-19 | 2002-01-31 | Innova Entwicklungs Gmbh | Component separating unit comprises rotor, rotor chamber, inlet and outlets, and partial chamber sections |
WO2004050255A2 (en) * | 2002-12-02 | 2004-06-17 | Rerum Cognitio Forschungszentrum Gmbh | Method for separating gas mixtures and a gas centrifuge for carrying out this method |
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PCT International Preliminary Report on Patentability for PCT/IT2004/000377 filed on Jul. 8, 2004 in the name of Luigi P. Della Casa. |
PCT International Search Report for PCT/IT2004/000377 filed on Jul. 8, 2004 in the name of Luigi P. Della Casa. |
PCT International Search Report for PCT/IT2004/000377, dated Mar. 7, 2005. * |
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PCT Written Opinion for PCT/IT2004/000377, dated Mar. 7, 2005. * |
Also Published As
Publication number | Publication date |
---|---|
US7905360B2 (en) | 2011-03-15 |
ATE535307T1 (en) | 2011-12-15 |
US20070289632A1 (en) | 2007-12-20 |
EP1763402B1 (en) | 2011-11-30 |
EP1763402A1 (en) | 2007-03-21 |
ES2376170T3 (en) | 2012-03-09 |
WO2006006186A1 (en) | 2006-01-19 |
CA2569784A1 (en) | 2006-01-19 |
CA2569784C (en) | 2010-08-31 |
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