U.S. patent application number 14/390513 was filed with the patent office on 2015-12-03 for hydroclone with vortex flow barrier.
This patent application is currently assigned to Dow Global Technologies LLC. The applicant listed for this patent is Dow Global Technologies LLC. Invention is credited to Steven D. JONS, Santhosh K. RAMALINGAM.
Application Number | 20150343334 14/390513 |
Document ID | / |
Family ID | 48538081 |
Filed Date | 2015-12-03 |
United States Patent
Application |
20150343334 |
Kind Code |
A1 |
JONS; Steven D. ; et
al. |
December 3, 2015 |
HYDROCLONE WITH VORTEX FLOW BARRIER
Abstract
A hydroclone (10) including a tank (12) having a fluid inlet
(14), a filtered fluid outlet (16), an effluent outlet (18), a
process fluid outlet (20) and an inner peripheral wall (22)
positioned about an axis (X) and enclosing a plurality of aligned
chambers including: i) a vortex chamber (24) in fluid communication
with the fluid inlet (14), a filter assembly (26) located within
the vortex chamber (24) and enclosing a filtrate chamber (46), a
fluid pathway (28) extending from the fluid inlet (14) and about
the filter assembly (26) which is adapted to generate a vortex
fluid flow about the filter assembly (26), wherein the filtrate
chamber (46) is in fluid communication with the filtered fluid
outlet (16) such that fluid passing through the filter assembly
(26) enters the filtrate chamber (46) and may exit the tank (12) by
way of the filtered fluid outlet (16), and ii) an effluent
separation chamber (30) in fluid communication with the vortex
chamber (24) and which is adapted for receiving unfiltered fluid
therefrom, wherein the effluent separation chamber (30) is in fluid
communication with the process fluid outlet (20) and an effluent
outlet (18); wherein the hydroclone (10) further includes a vortex
flow baffler (34) located between the vortex and effluent
separation chambers (24, 30) which is adapted to disrupts vortex
fluid flow as fluid flows from the vortex chamber (24) to the
effluent separation chamber (30).
Inventors: |
JONS; Steven D.; (Eden
Prairie, MN) ; RAMALINGAM; Santhosh K.; (Pearland,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Dow Global Technologies LLC |
Midland |
MI |
US |
|
|
Assignee: |
Dow Global Technologies LLC
Midland
MI
|
Family ID: |
48538081 |
Appl. No.: |
14/390513 |
Filed: |
May 22, 2013 |
PCT Filed: |
May 22, 2013 |
PCT NO: |
PCT/US2013/042127 |
371 Date: |
October 3, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61653788 |
May 31, 2012 |
|
|
|
Current U.S.
Class: |
210/195.1 ;
210/304 |
Current CPC
Class: |
B04C 2009/004 20130101;
B04C 5/04 20130101; B04C 5/14 20130101; B01D 29/6476 20130101; B01D
36/00 20130101; B04C 5/103 20130101; B01D 21/0006 20130101; B01D
21/0036 20130101; B01D 29/33 20130101; B01D 29/6415 20130101; B01D
21/0042 20130101; B01D 21/2411 20130101; B01D 21/267 20130101; B01D
21/0012 20130101; B04C 5/081 20130101; B01D 29/908 20130101; B04C
5/30 20130101; B04C 9/00 20130101; B04C 5/22 20130101 |
International
Class: |
B01D 21/26 20060101
B01D021/26; B01D 21/24 20060101 B01D021/24; B01D 21/00 20060101
B01D021/00 |
Claims
1-10. (canceled)
11. A hydroclone (10) comprising a tank (12) including a fluid
inlet (14), a filtered fluid outlet (16), an effluent outlet (18),
a process fluid outlet (20) and an inner peripheral wall (22)
positioned about an axis (X) and enclosing a plurality of axially
aligned chambers comprising: i) a vortex chamber (24) in fluid
communication with the fluid inlet (14), a filter assembly (26)
comprising an outer membrane surface (44) symmetrically located
about the axis (X) within the vortex chamber (24) and enclosing a
filtrate chamber (46) in fluid communication with the filtered
fluid outlet (16), a fluid treatment pathway (28) extending from
the fluid inlet (14) and about the filter assembly (26) which is
adapted to generate a vortex fluid flow about the filter assembly
(26), wherein the filtrate chamber (46) is in fluid communication
with the filtered fluid outlet (16) such that fluid passing through
the filter assembly (26) enters the filtrate chamber (46) and may
exit the tank (12) by way of the filtered fluid outlet (16), and
ii) an effluent separation chamber (30) adapted for receiving
unfiltered fluid from the vortex chamber (24), wherein the effluent
separation chamber (30) is in fluid communication with the effluent
outlet (18), a conduit (31) located in the effluent separation
chamber (30) and extending from an inlet (33) located near the axis
(X) to the process fluid outlet (20) located in the effluent
separation chamber (30) and a baffle (35) concentrically located
about the inlet (33) that blocks a linear fluid pathway into the
inlet (33), wherein the hydroclone (10) further comprises a vortex
flow barrier (34) located between the vortex and effluent
separation chambers (24, 30) which is adapted to disrupt vortex
fluid flow as fluid flows from the vortex chamber (24) to the
effluent separation chamber (30) and direct a majority of fluid
flow between the vortex and effluent separation (24, 30) chambers
to locations adjacent to the inner peripheral wall (22) of the tank
(12).
12. The hydroclone (10) of claim 11 wherein the vortex flow barrier
(34) comprises an outer periphery (40) extending to locations
adjacent to the inner peripheral wall (22) of the tank (12), and
further comprises a plurality of apertures (42) extending
therethrough.
13. The hydroclone (10) of claim 11 wherein the vortex flow barrier
(34) comprises an outer periphery (40) extending to locations
within at least 50 mm of the inner peripheral wall (22) of the tank
(12).
14. The hydroclone (10) of claim 11 wherein the vortex flow barrier
(34) comprises a disc shaped configuration.
15. The hydroclone (10) of claim 11 further comprising a cleaning
assembly (50) that is concentrically located and rotatably engaged
about the membrane surface (44).
16. The hydroclone (10) of claim 11 further comprising a
recirculation pump (Z) in fluid communication with the process
fluid outlet (20) and fluid inlet (14).
Description
TECHNICAL FIELD
[0001] The invention is generally directed toward hydroclones and
cyclonic separation of fluids.
BACKGROUND
[0002] Hydroclones are commonly used to separate suspended
particles from liquids. In a typical embodiment, pressurized feed
liquid (e.g. waste water) is introduced into a conically shaped
chamber under conditions that create a vortex within the chamber.
Feed liquid is introduced near the top of a conical chamber and an
effluent stream is discharged near the bottom of the chamber.
Centrifugal forces associated with the vortex urge denser particles
towards the periphery of the chamber. As a result, liquid located
near the center of the vortex has a lower concentration of
particles than that at the periphery. This "cleaner" liquid can
then be withdrawn from a central region of the hydroclone. Examples
of hydroclones are described in: U.S. Pat. Nos. 3,061,098,
3,529,724, 5,104,520, 5,407,584 and 5,478,484. Separation
efficiency can be improved by including a filter within the chamber
such that a portion of the liquid moving to the center of the
chamber passes through the filter. In such embodiments, cyclonic
separation is combined with cross-flow filtration. Examples of such
embodiments are described in: U.S. Pat. Nos. 7,632,416, 7,896,169,
U.S.2011/0120959 and U.S.2012/0010063. While such hybrid designs
improve separation efficiency, further improvements are
desired.
SUMMARY
[0003] The invention includes multiple embodiments of hydroclones,
separation systems including hydroclones and methods for performing
fluid separations using the same. In one embodiment, the invention
includes a hydroclone including a tank having a fluid inlet, a
filtered fluid outlet, an effluent outlet, a process fluid outlet
and an inner peripheral wall centered about an axis and enclosing a
plurality of aligned chambers including: i) a vortex chamber in
fluid communication with the fluid inlet, and ii) an effluent
separation chamber in fluid communication with the vortex chamber
and which is adapted for receiving unfiltered fluid therefrom,
wherein the effluent separation chamber is in fluid communication
with the process fluid outlet and an effluent outlet. The
hydroclone further includes a vortex flow barrier located between
the vortex chamber and effluent separation chamber which is adapted
to maintain vortex fluid flow in the vortex chamber, disrupt the
vortex as fluid flows between chambers and allow a reduced
rotational velocity fluid flow within the effluent separation
chamber. A filter assembly is located within the vortex chamber and
encloses a filtrate chamber. A fluid treatment pathway extends from
the fluid inlet and about the filter assembly and is adapted to
generate a vortex fluid flow about the filter assembly. The
filtrate chamber is in fluid communication with the filtered fluid
outlet such that fluid passing through the filter assembly may
enter the filtrate chamber and may exit the tank by way of the
filtered fluid outlet.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Various aspects of the invention may be better understood by
reference to the following description taken in conjunction with
the accompanying drawings wherein like numerals have been used
throughout the various views to designate like parts. The
depictions are illustrative and are not intended to be to scale or
otherwise limit the invention.
[0005] FIG. 1A is an elevational view showing one embodiment of the
invention.
[0006] FIG. 1B is a cross-sectional view taken along lines 1B-1B of
FIG. 1A.
[0007] FIG. 1C is a cross-sectional view of an alternative
embodiment illustrated in FIG. 1B.
[0008] FIG. 1D is a cross-sectional view of an alternative
embodiment illustrated in FIG. 1B.
[0009] FIG. 2 is an exploded perspective view of the embodiment
illustrated in FIG. 1A and B.
[0010] FIG. 3A is a perspective, partially cut-away view of a
filter assembly.
[0011] FIG. 3B is a perspective view of the filter of FIG. 2A
including a cleaning assembly.
[0012] FIG. 3C is a perspective view of the assembly of FIG. 2B
including an inlet flow shield.
[0013] FIG. 4A is a perspective view of one embodiment of a vortex
flow barrier.
[0014] FIG. 4B is a perspective view of an alternative embodiment
of a vortex flow barrier.
DETAILED DESCRIPTION
[0015] The present invention generally relates to the hydroclone
filtration devices and related methods of conducting cyclonic
separation. For purposes of the present description, the term
"hydroclone" refers to a filtration device that at least partially
relies upon centrifugal forces generated by vortex fluid flow to
separate constituents from a fluid mixture. Examples include the
separation of solid particles from a liquid mixture (e.g. aqueous
mixtures) and separation of mixtures including liquids of differing
densities (e.g. oil and water). In one embodiment, the invention
combines cyclonic separation, cross-flow filtration and particulate
settling (e.g. sedimentation or flocculation) within a
recirculation loop as part of a separation system. As used herein,
the term "system" refers to an interconnected assembly of
components. The invention finds utility in a variety of
applications including the treatment of: pulp effluent generating
by paper mills, process water generated by oil and gas recovery,
bilge water, and municipal and industrial waste water.
[0016] One embodiment of the invention is illustrated in FIGS. 1
and 2 including a hydroclone generally shown at 10 including a tank
(12) having a removable lid (13), a fluid inlet (14), a filtered
fluid outlet (16), an effluent outlet (18), a process fluid outlet
(20) and an inner peripheral wall (22) positioned about an axis (X)
and enclosing a plurality of aligned chambers. While depicted as
including two chambers, i.e. a vortex chamber (24) and an effluent
separation chamber (30), additional chambers may also be included.
Similarly, additional fluid inlets and outlets may also be
included. While shown as having a cylindrical upper section and a
frustro-conical base, the tank (12) may have other configurations
including a purely cylindrical shape. While shown as being
vertically aligned along a central axis (X), the vortex and
effluent separation chambers may be sequentially aligned along an
alternative axis, e.g. along a horizontal axis.
[0017] A filter assembly (26) is preferably centrally located
within the chamber (24) and is evenly spaced from the inner
peripheral wall (22) of the tank (12). As best shown in FIG. 3A,
the filter assembly (26) includes a cylindrical outer membrane
surface (44) symmetrically located about the axis (X) and enclosing
a filtrate chamber (46) that is in fluid communication with the
filtered fluid outlet (16). While shown as being shaped as a
cylinder, other configurations may be used including stepped and
conical shaped filters. The filter assembly (26) includes an outer
membrane surface (44) which may be fabricated from a wide variety
of materials including porous polymers, ceramics and metals. In one
embodiment, the membrane is relatively thin, e.g. from 0.2-0.4 mm
and is supported by an underlying rigid frame or porous support
(not shown). A representative example is described in
U.S.2012/0010063. The pore size (e.g. 1 to 500 micron), shape (e.g.
V-shape, cylindrical, slotted) and uniformity of the membrane (44)
may vary depending upon application. In many preferred embodiments,
the membrane (44) comprises a corrosion-resistant metal (e.g.
electroformed nickel screen) including uniform sized pores having
sizes from 10 to 100 microns. Representative examples of such
materials are described: U.S. Pat. Nos. 7,632,416, 7,896,169,
U.S.2011/0120959, U.S. 2011/0220586 and U.S.2012/0010063.
[0018] As best shown in FIG. 1B, a fluid treatment pathway (28)
extends from the fluid inlet (14) and defines a vortex region (25)
between the inner peripheral wall (22) of the chamber (24) and the
membrane surface (44). The fluid treatment pathway (28) continues
through the effluent separation chamber (30) to the process fluid
outlet (20).
[0019] The subject hydroclone (10) may further include a cleaning
assembly (50) for removing debris from the membrane surface (44) of
the filter assembly (26). A representative embodiment is
illustrated in FIG. 3B wherein the assembly (50) is concentrically
located and rotatably engaged about the membrane surface (44) and
includes one or more spokes (52) extending radially outward. A
brush (54) extends downward from the end of the spoke (52) and
engages (e.g. touches or comes very near to) the surface of the
membrane substrate (44). While shown as a brush (54), alternative
cleaning means may be included including wipers, squeegees or
scrappers. From 2 to 50 brushes, and preferably from 18 to 24
brushes are used in most embodiments. As represented by curved
arrows, the cleaning assembly (50) rotates about filter assembly
(26) such that the brush (54) sweeps the surface of the membrane
substrate (54) and removes debris, e.g. by creating turbulence near
the surface or by directly contacting the surface. One or more
paddles (56) may be mounted at the end of at least one spoke (52)
such that fluid flowing into the vortex chamber (24) rotates the
cleaning assembly (50) about the filter assembly (26). Spacing
paddles (56) evenly about the filter assembly adds stability to the
rotating movement of the cleaning assembly (50) and may help
maintain vortex fluid flow in the vortex chamber (24). While shown
as extending radially outward from the surface of the membrane
substrate (44), the paddles may be slanted, (e.g. from -5.degree.
to -30.degree. or 5.degree. to 30.degree. from the radial axis) to
increase rotational velocity. Bearings may be used between the
filter and cleaning assemblies (26, 50) to further facilitate
rotation without impeding vortex fluid flow. In alternative
embodiments not shown, the cleaning assembly (50) may be driven by
alternative means, e.g. electronic motor, magnetic force, etc. In
yet another embodiment, the filter assembly may move relative to a
fixed cleaning assembly.
[0020] The feed fluid inlet pressure and spacing between the outer
periphery of the filter assembly (26) and the inner peripheral wall
(22) of the tank (12) can be optimized to create and maintain a
vortex fluid flow within the chamber (24). In order to further
facilitate the creation and maintenance of vortex fluid flow, the
fluid inlet (14) preferably directs incoming feed fluid on a
tangential path about the vortex chamber, as indicated in FIG. 1A.
Even following such a tangential path, pressurized feed fluid may
directly impinge upon the membrane surface (44) of the filtration
assembly (26) and lead to premature wear or fouling--particularly
in connection with feed fluids having high solids content. To
protect the membrane surface (44), an inlet flow shield (58) may be
located between the fluid inlet (14) and the membrane surface (44),
e.g. concentrically located about the filter assembly (26).
Non-limiting embodiments are illustrated in FIGS. 2 and 3C. As
shown, the shield (58) preferably comprises a non-porous
cylindrical band of material, e.g. plastic, which blocks at least a
portion of fluid flowing into the chamber (24) from the fluid inlet
(14) from directly impinging upon (impacting) the membrane surface
(44). The band may be formed from a continuous loop of material or
by way of independent arcs. In a preferred embodiment, the shield
(58) has a height approximating the height of the membrane surface
(44) such that the shield (58) and membrane surface (44) forms
concentric cylinders. In a preferred embodiment, the shield may be
removably mounted to the cleaning assembly (50). By way of a
non-limiting example, the paddles (56) of the cleaning assembly
(50) may include vertical slots (60) for receiving the shield
(58).
[0021] A vortex flow barrier (34) is preferably located between the
vortex and effluent separation chambers (24, 30). The vortex flow
barrier (34) is designed to maintain vortex fluid flow in the
vortex chamber (24), disrupt the vortex as fluid flows from the
vortex chamber (24) into the effluent separation chamber (30), and
reduce the rotational fluid flow within the effluent separation
chamber (30). The vortex flow barrier (24) accomplishes this by
directing fluid flow between the vortex and effluent separation
(24, 30) chambers to locations adjacent to the inner peripheral
wall (22) of the tank (12). In a preferred embodiment illustrated
in FIG. 1B, the vortex flow barrier (34) includes an outer
periphery (40) extending to locations adjacent to (e.g. within 50
mm, 25 mm or even 10 mm) or in contact with the inner peripheral
wall (22) of the tank (12) and may optionally include a plurality
of apertures (42) located near the periphery (40) and extending
therethrough. The size and shape of apertures (42) is not
particularly limited, e.g. scalloped-shaped, slots, elliptical,
etc. A few representative examples are illustrated in FIG. 4A-B. In
yet other non-illustrated embodiment, the vortex flow barrier (34)
may include an outer periphery that includes no apertures and
extends to locations adjacent to (e.g. within 50 mm, 25 mm or even
10 mm) the inner peripheral wall (22) of the tank (12). The vortex
flow barrier (34) is designed to control the flow of fluid through
the chambers of the tank (12) with a majority (e.g. preferably at
least 50%, 75%, and in some embodiments at least 90%) of volumetric
flow being preferentially directed to locations near (e.g. within
at least 50 mm, 25 mm or even 10 mm) the inner peripheral wall (22)
of the tank (12). With that said, a minority (e.g. less than 50%
and more preferably less than 75% and still more preferably less
than 90%) of the fluid flow may occur at alternative locations
including the center location. While the illustrated embodiments
have a plate or disc configuration, the vortex flow barrier may
assume other configurations including one having an angled or
curved surface, e.g. cone- or bowl-shaped.
[0022] The effluent separation chamber (30) is adapted to enhance
separation of particles by reducing and redirecting fluid velocity.
The effluent separation chamber (30) is designed so that the bulk
of the fluid moves along the fluid treatment pathway (28) through a
region within the effluent separation chamber (300 where they
accelerate away from the effluent outlet (18), and in this region
their motion changes from moving toward the effluent outlet (18) to
moving away from the effluent outlet (18). In preferred
embodiments, this is at least partially accomplished by including a
fluid treatment pathway (28) that follows a serpentine path from
the vortex chamber (24) to the fluid outlet (20) which promotes the
separation and settling of particles from the bulk fluid flow due
to gravity. That is, by blocking a direct or near linear fluid
pathway within the effluent separation chamber (30), solids tend to
settle out of the more dynamic fluid flow, exiting the tank (12)
via the process fluid outlet (20).
[0023] As illustrated in FIG. 1B, the hydroclone (10) may also
include an optional conduit (31) including a process fluid inlet
(33) located near the axis (X) (e.g. centrally located) within the
effluent separation chamber (30) which is in fluid communication
with the process fluid outlet (20). As illustrated in FIG. 1C and
FIG. 1D, the process fluid inlet (33) may include a region wider
than the conduit (31) at its inlet to facilitate particle
collection and this wider region may be sloped as illustrated in
FIG. 1D. The hydroclone (10) may further include an optional baffle
(35) located about (e.g. concentrically) the inlet (33). The baffle
(35) limits the amount of solids entering the inlet (33) by
blocking a direct pathway. By blocking a direct or near linear
fluid pathway from the vortex chamber (24), solids tend to settle
out of the more dynamic fluid flow entering the inlet (33). In the
embodiments of FIGS. 1B, C and D, the axis (X) is vertically
aligned and the fluid inlet (33) faces vertically upward near the
center of the effluent separation chamber (30). In this
configuration, the fluid treatment pathway (28) follows a
serpentine path from the vortex chamber (24) to the fluid outlet
(20). Importantly, the path reverses course, initially flowing
generally downward and then upward, and finally downward within the
conduit (31). Particles within the bulk flowing along this pathway
tend to be drawn downward to the effluent outlet (18) and are
unable to reverse flow direction due to gravitational forces. While
not illustrated, alternative arrangements may also be used wherein
the inlet (33) faces downward and a baffle extends upward from the
bottom of the effluent separation chamber (30) and concentrically
about the inlet (33). The use of an optional baffle (35) enhances
the separation. While the baffle (35) is shown as having a
cylindrical structure, other structures which block a direct
pathway may also be used.
[0024] In operation, pressurized feed fluid (e.g. preferably from 4
to 120 psi) enters the tank (12) via the fluid inlet (14) and
follows along fluid treatment pathway (28) which generates a vortex
about the filter assembly (26). Centrifugal forces urge denser
materials toward the inner peripheral wall (22) of the tank (12)
while less dense liquid flows radially inward toward the filter
assembly (26). A portion of this liquid flows through the filter
assembly (26) into a filtrate chamber (46) and may subsequently
exit the tank (12) as "filtrate" by way of the filtered fluid
outlet (16). The remaining "non-filtrate" flows from the vortex
chamber (24) to the effluent separation chamber (30). The vortex
flow barrier (34) directs the majority (e.g. preferably at least
50%, 75%, and in some embodiments at least 90%) of such volumetric
flow to locations along or adjacent (e.g. within at least 50 mm, 25
mm or even 10 mm) to an inner peripheral wall (22) of the tank
(12). This arrangement is believed to maintain vortex flow within
the vortex chamber (24) while disrupting the vortex flow as fluid
enters the effluent separation chamber (30). Fluid flow slows in
the effluent separation chamber (30) and denser materials (e.g.
particles) preferentially settle toward the center of the effluent
separation chamber (30), enter into the effluent opening (38) and
may then exit the tank by way of effluent outlet (18). The effluent
outlet (18) may optionally include a valve (37) (e.g. one-way check
value or pump) to selectively control removal of effluent from the
tank (12). The remaining liquid (hereinafter referred to as
"process fluid") in the effluent separation chamber (30) flows out
of the tank (12) by way of the process fluid outlet (20). In most
applications, process fluid represents a mid-grade product that may
be re-used, disposed of, or recycled back to the fluid inlet (14)
for further treatment. "Filtrate" typically represents a high grade
product that may be re-used or disposed of. "Effluent" represents a
low grade product that may be further treated or disposed of.
However, it should be appreciated that in some applications,
effluent may represent a valuable product.
[0025] In another embodiment, the subject hydroclone (10) forms
part of a separation system that includes a feed pump (Y) in fluid
communication with the fluid inlet (14) that is adapted for
introducing a liquid mixture (feed) into the fluid inlet (14) and a
recirculation pump (Z) in fluid communication with the process
fluid outlet (20) and fluid inlet (14). The recirculation pump (Z)
is adapted for introducing process liquid from the process fluid
outlet (20) to the fluid inlet (14). The recirculation pump (Z)
along with the process fluid outlet (20), fluid inlet (14) and
fluid treatment pathway (28) collectively define a recirculation
loop (A).
[0026] The use of both a feed pump (Y) and recirculation pump (Z)
provide improved efficiencies over single pump designs allowing
economical operation when multiple passes through the recirculation
loop are used to remove particles. When each pass through the
effluent separation chamber (30) has relatively low recovery of
particles, several passes through the system are needed on average
to remove each particle. Within the vortex chamber (24), pressure
must exceed the trans-membrane pressure, and uniform flux along the
fluid treatment path (28) is more readily attained when systems are
designed for a higher trans-membrane pressure. Since pressure drops
associated with each pass are cumulative, a system designed around
a single pump can have substantial efficiency losses through
re-pressurization of each pass. By contrast, if a feed pump (Y) is
used to provide a pressurized liquid to a pressurized recirculation
loop driven by a second pump (Z), the energy losses on successive
passes associated with re-pressurizing to a trans-membrane pressure
and any filtrate back-pressure are avoided. The recirculation pump
(Z) needs only to supply energy to drive fluid through the
recirculation loop, and, in some embodiments, create relative
motion between the membrane surface (44) and cleaning assembly
(50). In a preferred embodiment, the recirculation pump (Z) is
adapted for introducing a volume of process liquid into the fluid
inlet (14) that is at least twice, more preferably three times, the
volume of feed liquid introduced by the feed pump (Y). While not
shown, the system (10) may include additional pumps and
corresponding valves for facilitating movement of liquids and
solids.
[0027] The subject hydroclones provide superior separation
efficiencies as compared with previous designs. These efficiencies
allow the hydroclone to be used in a broader range of applications;
particular in embodiments where process fluid is recycled and
optionally blended with make-up feed fluid. Broadly stated, feed
fluid is subjected to a synergistic combination of multiple
separation processes within a single device. Specifically, feed
fluid is subject to cyclonic separation based at least partially
upon density with denser material (e.g. particles, liquids) being
urged toward the inner periphery of the tank. Fluid passing through
the filter assembly is additionally subjected to cross-flow
filtration. The subject inlet feed shield prevents the membrane
used in cross-flow filtration from being subject to excessive wear
or fouling attributed to the feed pressures and feed content
associated with cyclonic separations. The entire subject matter of
each of the US patents mentioned herein references are fully
incorporated by reference.
* * * * *