Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D25/00—Filters formed by clamping together several filtering elements or parts of such elements
  • B01D25/12—Filter presses, i.e. of the plate or plate and frame type
  • B01D25/164—Chamber-plate presses, i.e. the sides of the filtering elements being clamped between two successive filtering plates
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D25/00—Filters formed by clamping together several filtering elements or parts of such elements
  • B01D25/12—Filter presses, i.e. of the plate or plate and frame type
  • B01D25/172—Plate spreading means
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D25/00—Filters formed by clamping together several filtering elements or parts of such elements
  • B01D25/32—Removal of the filter cakes
  • B01D25/34—Removal of the filter cakes by moving, e.g. rotating, the filter elements

Definitions

• Dewatering can be effected, for example, in a chamber filter press, whereby a higher dry content and thereby a substantial reduction of the sludge volume is obtained.
• the present invention has the object to facilitate the utilization of a chamber filter press in connection with the dewatering of waste sludge, and particularly to facilitate the removal of the sludge cakes from the filter plates and clothes.
• This object is achieved according to the invention, in that between a filter cloth covering the plate and the plate one or more membranes are provided, which cover only a part of the total filter plate surface, and which by supply of a medium under pressure can be expanded from the compressed position assumed at the pressing so as to extend or bulge the filter cloth so that the contact surface between the cloth and the filter cake decreases, and thereby also the adherence of the filter cake on the cloth decreases, so that the filter cake due to gravity detaches from the cloth and plate.
• the membranes preferably can have the form of hoses, and the expansion is effected by compressed air.
• rubber membranes can alternatingly be filled with air and emptied. The pulsating motion to which the filter clothes thereby are subjected, causes vibrations of the sludge cake, which thereby loosens.
• the invention implies the possibility of separating several (possibly all) filter plates from each other at the same time, whereby the time required for emptying is reduced substantially.
• the mechanism for moving the plates besides, can be simple because it can be based on compressed air.
• the movable parts even can be restricted to be only the plates, and the membrane motion is utilized for separating the plates.
• Fig. 1 is a schematic lateral view of some filter plates in a chamber filter press
• Fig . 2 is a front view of a filter plate
• Fig . 3 is a lateral sectional view in greater detail
• Fig . 4 is a sectional view of two filter plates and an intermediate filter cake
• Fig . 5 shows a complementary separation device.
• the chamber filter press shown in Fig. 1 schematically comprises a stand 11, in which a plurality of filter plates 1 are flexibly suspended.
• the filter plate package is com pressed for pressing out the water by means of a hydraulic piston 12 and an intermediate plate 13.
• each filter plate 1 includes on each side cupped recesses 2 so that only a wide edge remains which extends all about.
• Each filter plate 1 is coated on both sides with filter cloth 3, which is stretched so loosely that it can be pressed into the cupped recess 2 in the filter plate 1.
• the filter cloth is attached to the filter plate along the edge extending all about and to the centre of the recess 2.
• In the filter plate drain passageways are arranged, which are shown schematically in the form of a tap at 4.
• each recess 2 in the respective filter plate two (or more) soft rubber hoses 5 are provided, one on each side of the central attachment point of the filter cloth.
• the rubber hoses 5 are connected to sealed air passageways 15, which extend through the edges of the filter plate 1 out to compressed air connections (not shown).
• the hoses 5 are closed at their opposite ends.
• the membranes have designs other than rubber hoses, and also the pressure medium may be another one than air.
• a wheel 9 can be used which is located above the filter plates and upon rotation moves one plate at a time, in that a recess 10 in the wheel hooks on a pin attached to the respective filter plate.
• the distance, through which each plate is moved, is determined by the wheel diameter.
• the wheel is fixed in vertical direction and moves horizontally when a plate is being moved, whereby the plate next in turn is moved at the next wheel rotation.
• This complementary opening mechanism is particularly motivated when the filter press has great length, because then the force from the membranes may not be sufficient for the distribution of the filter plates.
• FIG. 5 appears in detail how the filter plates are flexibly suspended on horizontal, horizontally movable pins 7 via strips or the like 8.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Filtration Of Liquid (AREA)
• Valves And Accessory Devices For Braking Systems (AREA)
• Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
• Fluid-Pressure Circuits (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20339488

Family Applications (1)

Country Status (5)

Families Citing this family (4)

Family Cites Families (11)

• 1979
  • 1979-12-06 SE SE7910058A patent/SE7910058L/xx not_active Application Discontinuation
• 1980
  • 1980-12-05 FI FI803798A patent/FI803798A7/fi not_active Application Discontinuation
  • 1980-12-05 WO PCT/SE1980/000321 patent/WO1981001665A1/en not_active Ceased
  • 1980-12-05 EP EP81900025A patent/EP0041532A1/en not_active Withdrawn
• 1981
  • 1981-08-05 NO NO812652A patent/NO812652L/no unknown

Non-Patent Citations (1)

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