Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/15—Filters with filtering elements which move during the filtering operation with rotary plane filtering surfaces
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/15—Filters with filtering elements which move during the filtering operation with rotary plane filtering surfaces
  • B01D33/21—Filters with filtering elements which move during the filtering operation with rotary plane filtering surfaces with hollow filtering discs transversely mounted on a hollow rotary shaft
  • B01D33/23—Construction of discs or component sectors thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/44—Regenerating the filter material in the filter
  • B01D33/46—Regenerating the filter material in the filter by scrapers, brushes nozzles or the like acting on the cake-side of the filtering element
  • B01D33/463—Regenerating the filter material in the filter by scrapers, brushes nozzles or the like acting on the cake-side of the filtering element nozzles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/44—Regenerating the filter material in the filter
  • B01D33/46—Regenerating the filter material in the filter by scrapers, brushes nozzles or the like acting on the cake-side of the filtering element
  • B01D33/466—Regenerating the filter material in the filter by scrapers, brushes nozzles or the like acting on the cake-side of the filtering element scrapers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/58—Handling the filter cake in the filter for purposes other than for regenerating the filter cake remaining on the filtering element
  • B01D33/60—Handling the filter cake in the filter for purposes other than for regenerating the filter cake remaining on the filtering element for washing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/58—Handling the filter cake in the filter for purposes other than for regenerating the filter cake remaining on the filtering element
  • B01D33/68—Retarding cake deposition on the filter during the filtration period, e.g. using stirrers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/80—Accessories
  • B01D33/804—Accessories integrally combined with devices for controlling the filtration
  • B01D33/807—Accessories integrally combined with devices for controlling the filtration by level measuring
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/80—Accessories
  • B01D33/804—Accessories integrally combined with devices for controlling the filtration
  • B01D33/808—Accessories integrally combined with devices for controlling the filtration by pressure measuring
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2201/00—Details relating to filtering apparatus
  • B01D2201/20—Pressure-related systems for filters
  • B01D2201/204—Systems for applying vacuum to filters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2201/00—Details relating to filtering apparatus
  • B01D2201/28—Position of the filtering element
  • B01D2201/282—Filtering elements with a horizontal rotation or symmetry axis
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D35/00—Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
  • B01D35/30—Filter housing constructions
  • B01D35/31—Filter housing constructions including arrangements for environmental protection, e.g. pressure resisting features

Definitions

• the invention relates generally to an agitator used in a disc filter and in
• Disc filters for separating solid particles from liquid are known in the art.
• the disc filter includes a plurality of
• hollow discs 2 having side walls 3 of a filter material.
• the hollow discs 2 are coupled
• the discs 2 are positioned within a container 5
• a vacuum pump 7 draws the liquid through the
• the container 5 is filled approximately halfway with
• Sections of the disc 2 rotate counter-clockwise, enter the slurry and emerge
• a scraper 11 is used to remove solid material formed on
• the precoat acts as an additional filter.
• the scraper 11 removes a layer of solid material (referred to as the cake layer) formed on top of the cake layer
• the precoat layer becomes less
• the spray nozzle 15 moves between the periphery and center
• the disc filter shown in FIGURES 1 and 2 may also be equipped with an
• solid particles must be distributed throughout the liquid. This allows the solid particles
• the agitation prevents the solid particles from accumulating at the bottom of
• an agitator 24 is
• the disc filter is forced towards the discs 2 through pressure in the container 5.
• the disc filter includes oscillating showers that periodically
• the oscillating shower moves faster than at the exterior of the disc
• the disc filter also includes an agitator that forces a portion
• the oscillating shower that oscillates at varying speeds sprays a uniform amount
• the precoat layer and reduces the number of nozzles. Reducing the number of nozzles
• the eductor agitator receives the input slurry and uses a portion of the slurry
• the filter capacity is also improved by not introducing
• FIGURE 1 is a cross-sectional side view of a conventional disc filter
• FIGURE 2 is a cross-sectional end view of the conventional disc filter
• FIGURE 3 is a cross-sectional side view of a conventional disc filter including
• FIGURE 4 is a cross-sectional end view of the disc filter of the present
• FIGURE 4A is a block diagram of the disc filter control system
• FIGURE 5 is an enlarged view of the oscillating shower wand
• FIGURE 6 is a cross-sectional side view of the disc filter of FIGURE 4.
• FIGURE 7 is an enlarged view of the oscillating shower actuator
• FIGURES 8A-8C illustrate the path and speed of the oscillating shower over the
• FIGURE 9 is an enlarged, exploded view of an eductor agitator.
• FIGURE 4 is cross-sectional end view of the disc filter of the present invention.
• the disc filter includes at least one disc 2.
• the disc 2 is similar to those described in
• the liquid is forced through the discs 2 by creating a pressure
• a perforated material such as metal and covered with a filter material such as
• the filter material is referred to generally as the filter cloth.
• the discs 2 is divided into disc sectors 70 which are covered with the filter cloth.
• the discs 2 are divided into disc sectors 70 which are covered with the filter cloth.
• the level of the slurry can vary but typically is approximately the center of the disc 2. As the discs 2
• each sector 70 fully enters the slurry and an amount of solid material is
• An oscillating shower 30 includes an oscillating shower wand 32 having shower
• the oscillating shower 30 is used to remove the precoat layer of solids
• the precoat layer has become impervious to
• the container 5 is drained, the disc 2 is rotated
• the oscillating shower uniformly sprays the surface of
• FIGURES 8A-8C are identical to FIGURES 8A-8C.
• a scraper mechanism 40 includes a blade 42 that removes the cake layer from
• the disc 2 rotates counter-clockwise (as shown on
• the solid material is sluiced down into the lime mud mix tank, using
• chute sprays and recirculated slurry from the mix tank.
• a wash shower 50 is an optional addition to the disc filter.
• the wash shower 50 is an optional addition to the disc filter.
• the wash shower includes a wash pipe 52 and a plurality of wash shower nozzles 54.
• the wash shower includes a wash pipe 52 and a plurality of wash shower nozzles 54.
• nozzles 54 spray water at the solid material formed on the disc sectors 70 as each disc
• Wash shower 50 replaces a portion of
• agitator 60 agitates the slurry in the container 5. If the slurry is not agitated, the solid
• the solid material accumulates at the bottom of the container 5 can be extremely low
• an eductor agitator 60 is positioned at each side of each disc.
• the wash shower 50 if used, displaces the liquid to prevent the liquid from being
• precoat layer becomes too impervious and must be removed to sustain filter capacity.
• shower 30 removes the precoat layer. Once the precoat layer is removed, the filtering
• initiate the oscillating shower 30 may be made automatically by control circuitry.
• a pressure sensor 210 positioned within the container 5 detects the level of the slurry.
• control circuitry Upon detection of one or both of these conditions, the control circuitry
• FIGURE 5 is an enlarged view of the oscillating shower 30 shown in FIGURE
• the oscillating shower wand 32 is made up of an upper section 35 and a nozzle
• the coupler 36 allows the nozzle section 33 to be removed from
• the oscillating shower wand 32 receives
• the high pressure pipe 31 is mounted in
• FIGURE 5 shows the
• FIGURE 6 is a side cross-sectional view of the disc filter. As described above,
• the oscillating shower wands 32 are coupled to a high pressure pipe 31.
• Nozzles 34 extend away from the oscillating shower wand 32 and direct a spray of water at the surface of the discs 2.
• the oscillating shower wands 32 are driven by a pneumatic actuator 82 which is
• the pneumatic actuator 82 drives an actuator arm
• a feed pipe 84 provides water to the
• the feed pipe includes a rotating section 89 which is coupled to
• a bearing/swivel joint 86 couples the rotating section 89 to
• section 89 is connected to the high pressure pipe 31 through a split seal 83 and a seal
• the seal mounting plate 81 seals the container 5 at the area where
• the high pressure pipe 31 extends through the container wall.
• FIGURE 7 is an enlarged end view of the region including the pneumatic
• the bearing/swivel joint 86 is not shown in FIGURE 7 for clarity.
• pneumatic actuator 82 is mounted to a pivot joint 88 which allows the pneumatic
• the actuator arm 85 is
• connection arm (not shown in the drawings) welded to the rotating section 89 and rotatably coupled to the actuator arm
• section 89 rotates and causes the high pressure pipe 31 to rotate in an oscillatory
• FIGURES 8A-8C illustrate the path followed by the oscillating shower nozzles
• FIGURE 8A illustrates a single
• FIGURE 8B illustrates a double pass
• FIGURE 8C
• the oscillating shower wand 32 travels between a first radial position and a second
• the second radial position is at or near the periphery of the disc 2.
• the second radial position is near the
• the track 90 is divided into a plurality of track sections 92 that indicate the
• track sections 92 near the center of the disc are larger than the track sections 92 at the
• the shower nozzles 34 move faster near the center of the disc
• the pneumatic arm 85 is driven faster when the
• nozzles 34 are near the center of the disc and slower when the nozzles 34 are near the
• nozzles 34 slow down in order to achieve uniform coverage of the disc surface.
• FIGURE 8B illustrates the amount of coverage when the
• the variance in the speed of the shower nozzles provides several advantages.
• FIGURE 9 is an enlarged, exploded view of the eductor agitator 60 shown in
• the eductor agitator 60 includes an eductor inlet pipe 62.
• inlet pipe 62 is fed from the main inlet pipe that provides the slurry to the container 5.
• the eductor inlet pipe 62 is coupled to an eductor nozzle 64 which increases the
• the eductor nozzle 64 is mounted on the eductor inlet pipe 62.
• the inlet pipe has a flange 622 which provides for mounting the inlet pipe 62 and the
• the eductor assembly 66 has a flange 662 which
• eductor inlet 664 is a cylindrical opening having an inner diameter slightly larger than
• the feed slurry is fed from the feed pipe into the
• eductor agitator 60 is preferably placed at each side of each disc 2. In this way, the
• the eductor agitators 60 may be fed
• the oscillating shower uses variable
• the oscillating shower wand moves slower than near the
• the disc filter includes eductor agitators that maintain
• agitators also prevent the solid material from accumulating at the bottom of the

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Filtration Of Liquid (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (2)

Family

ID=24933157

Family Applications (1)

Country Status (7)

Cited By (4)

Citations (4)

Family Cites Families (1)

• 1997
  • 1997-10-14 CA CA002268936A patent/CA2268936A1/en not_active Abandoned
  • 1997-10-14 WO PCT/US1997/018896 patent/WO1998016292A2/en active Application Filing
  • 1997-10-14 AU AU49090/97A patent/AU4909097A/en not_active Abandoned
  • 1997-10-14 ID IDW990324D patent/ID23778A/id unknown
  • 1997-12-16 TW TW086115124A patent/TW346407B/zh active
• 1999
  • 1999-04-15 SE SE9901347A patent/SE9901347L/sv not_active Application Discontinuation
  • 1999-04-15 FI FI990841A patent/FI990841A/sv unknown

Patent Citations (4)

Non-Patent Citations (1)

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