Displacement filter apparatus and method

A filter apparatus for dewatering a slurry, comprising:

• a pressure vessel having a first end, a second end, and a one-piece, annular side wall portion, said side wall portion having an internal surface generally defining an internal space, one of said first end and said second end defining an opening to permit access to said internal space;
• a closure sized and shaped for selectively closing said opening;
• an annular inner filter defining an external surface and an internal cavity, said internal cavity at least partially defining a first outlet space, a substantial portion of said inner filter which forms said external surface comprising a first filter media;
• an outer filter surrounding said inner filter and defining an internal surface facing said external surface, said internal surface and said external surface being substantially parallel, a substantial portion of said outer filter which forms said internal surface comprising a second filter media, said first filter media and said second filter media comprising one of a woven material and a material configured to retain a particulate size greater than or equal to about 0.25 microns, said first and second filter media defining an annular particulate collection volume therebetween, said outer filter and said internal surface of said vessel defining a second outlet space therebetween;
• an inlet communicating with said internal space, said inlet configured to direct a slurry into said particulate collection volume before passing through either of said inner filter and said outer filter;
• an outlet communicating with said internal space, said outlet being in fluid communication with said first outlet space and said second outlet space;
• a pressure source upstream from said inlet, wherein pressure from said pressure source is directable through said inlet to force a fluid component of a slurry within said particulate collection volume through said inner filter to said first outlet space and through said outer filter to said second outlet space, said first and second filter media retaining a solid component of a slurry within said particulate collection volume to form a particulate cake, and said opening being sized and shaped to permit a particulate cake within said particulate collection volume to be removed through said opening;
• wherein said pressure source produces a first fluid pressure upstream from said particulate collection volume and a second fluid pressure downstream from said particulate collection volume, the difference between said first fluid pressure and said second fluid pressure defining a pressure differential, said filter apparatus configured to withstand operating pressure differentials of at least 25 psi.

A filter apparatus for filtering a slurry, comprising:

• a pressure vessel having a first end, a second end and an annular wall, a support portion configured to secure said pressure vessel in a location, said wall of said pressure vessel including a first portion between said support and one of said first end and said second end of said vessel, said first portion of said wall being capable of providing sufficient resistance to gravity acting on said first portion of said wall to maintain the structural integrity of said first portion of said wall;
• an annular inner filter defining an external surface and an internal cavity, said internal cavity at least partially defining a first outlet space, a substantial portion of said inner filter which forms said external surface comprising a first filter media;
• an outer filter surrounding said inner filter and defining an internal surface facing said external surface, a substantial portion of said outer filter which forms said internal surface comprising a second filter media, said first filter media and said second filter media comprising one of a woven material and a material configured to retain a particulate size greater than or equal to about 0.25 microns, said first and second filter media defining an annular particulate collection volume therebetween, said outer filter and said internal surface of said vessel defining a second outlet space therebetween;
• an inlet communicating with said internal space, said inlet directing said slurry into said particulate collection volume before passing through either of said inner filter and said outer filter;
• an outlet communicating with said internal space, said outlet being in fluid communication with said first outlet space and said second outlet space;
• a pressure source upstream from said inlet, wherein pressure from said pressure source is directable through said inlet to force a fluid component of a slurry within said particulate collection volume through said inner filter to said first outlet space and through said outer filter to said second outlet space, said first and second filter media retaining a solid component of a slurry within said particulate collection volume to form a particulate cake.

A filter apparatus for dewatering a slurry, comprising:

• a pressure vessel having a first end, a second end, and a one-piece, annular side wall portion, said side wall portion having an internal surface generally defining an internal space, one of said first end and said second end defining an opening to permit access to said internal space;
• a closure sized and shaped for selectively closing said opening, said pressure vessel and said closure configured to withstand a pressure of at least 25 psi in said internal space when said opening is closed;
• at least one filter assembly comprising a first filter and a second filter, said first filter defining a first surface and at least partially defining a first outlet space, a substantial portion of said first filter which forms said first surface comprising a first filter media, said second filter defining a second surface facing said first surface, said second filter at least partially defining a second outlet space, a substantial portion of said second filter which forms said second surface comprising a second filter media, said first and second filter media defining a particulate collection volume therebetween;
• an inlet communicating with said internal space, said inlet configured to direct a slurry into said particulate collection volume before passing through either of said first filter and said second filter;
• an outlet communicating with said internal space, said outlet being in fluid communication with said first outlet space and said second outlet space;
• a pressure source upstream from said inlet, wherein pressure from said pressure source is directable through said inlet to force a fluid component of a slurry within said particulate collection volume through said first filter to said first outlet space and through said second filter to said second outlet space, said first and second filter media retaining a solid component of a slurry within said particulate collection volume to form a particulate cake, and said opening being sized and shaped to permit a particulate cake within said particulate collection volume to be removed through said opening;
• a scraper sized and shaped to extend substantially from said first filter media to said second filter media, said scraper being movable from a first end of said particulate collection volume toward a second end of said particulate collection volume to remove particulate cake from said particulate collection volume.

A filter apparatus for dewatering a slurry, comprising:

• a pressure vessel having a first end, a second end, and a one-piece, annular side wall portion, said side wall portion having an internal surface generally defining an internal space, one of said first end and said second end defining an opening to permit access to said internal space;
• a closure sized and shaped for selectively closing said opening;
• at least one filter assembly comprising a first filter and a second filter, said first filter defining a first surface and at least partially defining a first outlet space, a substantial portion of said first filter which forms said first surface comprising a first filter media, said second filter defining a second surface facing said first surface and at least partially defining a second outlet space, said first surface and said second surface being substantially parallel, a substantial portion of said second filter which forms said second surface comprising a second filter media, said first and second filter media defining a particulate collection volume therebetween;
• an inlet communicating with said internal space, said inlet configured to direct a slurry into said particulate collection volume before passing through either of said first filter and said second filter;
• an outlet communicating with said internal space, said outlet being in fluid communication with said first outlet space and said second outlet space;
• a pressure source upstream from said inlet, wherein pressure from said pressure source is directable through said inlet to force a fluid component of a slurry within said particulate collection volume through said first filter to said first outlet space and through said second filter to said second outlet space, said first and second filter media retaining a solid component of a slurry within said particulate collection volume to form a particulate cake, and said opening being sized and shaped to permit a particulate cake within said particulate collection volume to be removed through said opening;
• wherein said pressure source produces a first fluid pressure upstream from said particulate collection volume and a second fluid pressure downstream from said particulate collection volume, the difference between said first fluid pressure and said second fluid pressure defining a pressure differential, said filter apparatus configured to withstand operating pressure differentials of at least 25 psi;
• and
• a scraper sized and shaped to extend substantially from said first filter media to said second filter media, said scraper being movable from a first end of said particulate collection volume toward a second end of said particulate collection volume to remove particulate cake from said particulate collection volume.

A filter apparatus for filtering a slurry, comprising:

• a pressure vessel having a first end, a second end and an annular wall, a support portion configured to secure said pressure vessel in a location, said wall of said pressure vessel including a first portion between said support and one of said first end and said second end of said vessel, said first portion of said wall being capable of providing sufficient resistance to gravity acting on said first portion of said wall to maintain the structural integrity of said first portion of said wall;
• at least one filter assembly comprising a first filter and a second filter, said first filter defining a first surface and at least partially defining a first outlet space, a substantial portion of said first filter which forms said first surface comprising a first filter media, said second filter defining a second surface facing said first surface and at least partially defining a second outlet space, a substantial portion of said second filter which forms said second surface comprising a second filter media, said first and second filter media defining a particulate collection volume therebetween;
• an inlet communicating with said internal space, said inlet directing said slurry into said particulate collection volume before passing through either of said first filter and said second filter;
• an outlet communicating with said internal space, said outlet being in fluid communication with said first outlet space and said second outlet space;
• a pressure source upstream from said inlet, wherein pressure from said pressure source is directable through said inlet to force a fluid component of a slurry within said particulate collection volume through said first filter to said first outlet space and through said second filter to said second outlet space, said first and second filter media retaining a solid component of a slurry within said particulate collection volume to form a particulate cake;
• and
• a scraper sized and shaped to extend substantially from said first filter media to said second filter media, said scraper being movable from a first end of said particulate collection volume toward a second end of said particulate collection volume to remove particulate cake from said particulate collection volume.

A filter apparatus, comprising:

• a pressure vessel having a first end, a second end, and a cylindrical wall portion extending between said first and second ends, said pressure vessel defining an internal space, one of said first end and said second end comprising an opening to permit access to said internal space;
• a closure sized and shaped for selectively closing said opening;
• at least one filter assembly within said internal space, said at least one filter assembly defining a first filter surface and a second filter surface facing said first filter surface, said first filter surface and said second filter surface at least partially defining a particulate collection volume therebetween;
• an inlet directing a slurry into said particulate collection volume before said fluid passes through either of said first filter surface and said second filter surface;
• at least one outlet located downstream from at least one of said first filter surface and said second filter surface;
• a pressure source upstream from said inlet, wherein pressure from said pressure source is directed through said inlet to force a fluid component of said slurry within said collection volume through said first filter surface and said second filter surface to said at least one outlet, said first filter surface and said second filter surface retaining a solid component of said slurry within said particulate collection volume to form a particulate cake, said opening being sized and shaped such that a particulate cake formed in said particulate collection volume is removable through said opening.

A filter apparatus, comprising:

• an annular inner filter defining an internal cavity;
• an outer filter surrounding said inner filter, said inner filter and said outer filter defining an annular particulate collection volume when said filter apparatus is in a closed position, said inner filter and said outer filter being movable axially with respect to one another to define an open position wherein particulate may be emptied from said filter apparatus;
• an outlet located downstream from said particulate collection volume;
• an inlet directing fluid into said particulate collection volume before said fluid passes through either of said inner filter and said outer filter;
• and
• a drive having a portion which exerts force on at least one of said inner filter and said outer filter to move said filter apparatus between said open position and said closed position.

A filter apparatus, comprising:

• an annular inner filter defining an internal cavity;
• an outer filter surrounding said inner filter, said inner filter and said outer filter defining an annular particulate collection volume when said filter apparatus is in a closed position, said inner filter and said outer filter being movable axially with respect to one another to define an open position wherein particulate may be emptied from said filter apparatus;
• an outlet located downstream from said particulate collection volume;
• an inlet directing fluid into said particulate collection volume before said fluid passes through either of said inner filter and said outer filter;
• and
• means for moving said filter apparatus between said open position and said closed position.