Patent ID: 8900450
Filing Date: 2014-12-02
Classification: B01D,C02F

Abstract:
1. A filter press, comprising: a supporting frame, said supporting frame comprising a fixed headpiece, a foot and at least one longitudinal guide, said at least one longitudinal guide defining a longitudinal axis, said at least one longitudinal guide extending between the fixed headpiece on one side and the foot on the other side; a first compressive device, configured to compress filtering plates one onto the other, said first compressive device comprising at least a first rotatable screw and a second rotatable screw, and a movable headpiece, said first and said second rotatable screws operable for locking said moveable headpiece in a position along said longitudinal axis in relation to said fixed headpiece, without a fixed locking mechanism in a discretely fixed position relative to said supporting frame and parallel to said longitudinal axis; wherein said filtering plates are supported by said at least one longitudinal guide, said filtering plates being arranged side by side, said filtering plates extending between said fixed headpiece and said movable headpiece, wherein said first rotatable screw is spaced apart and parallel to said second rotatable screw, said rotatable screws being oriented along said longitudinal axis, and wherein said movable headpiece is supported by said at least one longitudinal guide, said movable headpiece comprising at least a first threaded cylindrical hole and a second threaded cylindrical hole, said first threaded cylindrical hole receiving said first rotatable screw therethrough, and said second threaded cylindrical hole receiving said second rotatable screw therethrough, said filter press further comprising: a second compressive device, configured to compress said filtering plates one onto the other, said second compressive device comprising at least one pneumatic or hydraulic cushion and a compression plate, wherein said at least one pneumatic or hydraulic cushion and said compression plate are positioned behind or before said fixed headpiece in relation to said moving headpiece and wherein said at least one pneumatic or hydraulic cushion are inflatable by a fluid to operate on said compression plate to compress said filtering plates between said movable headpiece and said fixed headpiece; wherein said rotatable screws are rotatably coupled with said supporting frame, and wherein the filter press is configured so that: said first compressive device operates first to provide a first compression force on said filtering plates, said second compressive device operates subsequently to provide a second compression force on said filtering plates, said second compression force being greater than the first compression force; said first compressive device operates subsequently to provide a third compression force on said filtering plates; and said second compressive device operates subsequently to provide a final compression force on said filtering plates, wherein said first compression force, said second compression force, said third compression force and said fourth compression force are each exerted so as to press said filtering plates one onto the other, and wherein, in operation, a slurry to be dehydrated is introduced in the filter press immediately after application of said first compression force.