Cross-flow filtration

In a cross-flow filter comprising:

• means for mounting a filter support in position;
• a flexible filter support mounted by the mounting means;
• an inlet for leading feed to said filter support;
• an outlet for permeate which has passed through said filter support;
• and an outlet for concentrate which has not passed through said filter support;
• the improvement that said filter support is in the form of a material of a tight textile construction of high pressure rating and low extensibility having two plies which are entangled together at parallel, spaced seams to form an integral array of side-by-side, continuous, separate tubes, said seams being strong enough to resist a relative pressure of about 59 p.s.i. in said tubes, and said plies providing tube walls each of which has a flexural rigidity in at least one direction greater than zero and of not more than 2500 mg.cm according to British Standard 3356:
• 1961, said inlet being connected to the interior of said tubes whereby when said tubes are under the pressure of said feed, said walls provide an uninterrupted filter zone of substantial area which is restrained during filtration solely by tensile forces in said walls, substantial movement of said walls being possible in the direction at right angles to said walls when the pressures inside said tubes and outside said tubes are equal.

In a cross-flow filter comprising:

• means for mounting a filter support in position;
• a flexible filter support mounted by the mounting means;
• an inlet for leading feed to said filter support;
• an outlet for permeate which has passed through said filter support;
• and an outlet for concentrate which has not passed through said filter support;
• the improvement that said filter support is in the form of a woven material formed of longitudinal threads and transverse threads and having two plies which are connected together at parallel, spaced seams to form an integral array of side-by-side, continuous, separate tubes extending parallel to said longitudinal threads, at said seams the transverse threads of one ply passing under at least one longitudinal thread over which the transverse threads of the other ply pass, said seams being strong enough to resist a relative pressure of about 59 p.s.i. in said tubes, and said plies providing tube walls each of which has a flexural rigidity in at least one direction greater than zero and of not more than 2500 mg.cm according to British Standard 3356:
• 1961, said inlet being connected to the interior of said tubes whereby when said tubes are under the pressure of said feed, said walls provide an uninterrupted filter zone of substantial area which is restrained during filtration solely by tensile forces in said walls, substantial movement of said walls being possible in the direction at right angles to said walls when the pressure inside said tubes and outside said tubes are equal.

In a cross-flow filter comprising:

• means for mounting a filter support in position;
• a flexible filter support mounted by the mounting means;
• an inlet for leading feed to said filter support;
• an outlet for permeate which has passed through said filter support;
• and an outlet for concentrate which has not passed through said filter support;
• the improvement that said filter support is in the form of a woven material formed of longitudinal threads and transverse threads and having two plies which are connected together at parallel, spaced seams to form an integral array of side-by-side, continuous, separate tubes extending parallel to said longitudinal threads, at said seams the transverse threads of one ply passing under at least one longitudinal thread over which the transverse threads of the other ply pass, said seams being strong enough to resist a relative pressure of about 59 p.s.i. in said tubes, and said plies providing tube walls each of which has a flexural rigidity such that a rectangular piece having four sides cut from the wall and placed on a horizontal table with an edge of the table parallel to one of the sides of the piece protrudes 100 mm or less to obtain a droop angle of the protrusion of 45.degree. with the piece clamped by a clamping member aligned with the edge of the table, which protrusion is greater than zero, said in inlet being connected to the interior of said tubes whereby when said tubes are under the pressure of said feed, said walls provide an uninterrupted filter zone of substantial area which is restrained during filtration solely by tensile forces in said walls, substantial movement of said walls being possible in the direction at right angles to said walls when the pressures inside said tubes and outside said tubes are equal.

A filter support for a cross-flow filter which comprises:

• means for mounting a filter support in position;
• a flexible filter support mounted by the mounting means;
• an inlet for leading feed to the filter support;
• an outlet for permeate which has passed through the filter support;
• and an outlet for concentrate which has not passed through the filter support;
• said filter support being in the form of a material having two plies which are connected together at parallel, spaced seams to form an integral array of side-by-side, continuous, separate tubes, said seams being strong enough to resist a relative pressure of about 59 p.s.i. in said tubes, and said plies providing tube walls each of which has a flexural rigidity in at least one direction greater than zero and of not more than 2500 mg.cm according to British Standard 3356:
• 1961, said inlet being connectable to the interior of said tubes whereby when said tubes are under the pressure of said feed, said walls provide an uninterrupted filter zone of substantial area which is restrained during filtration solely by tensile forces in said walls, substantial movement of said walls being possible in the direction at right angles to said walls when the pressures inside said tubes and outside said tubes are equal.

A filter support for a cross-flow filter which comprises:

• means for mounting a filter support in position;
• a flexible filter support mounted by the mounting means;
• an inlet for leading feed to the filter support;
• an outlet for permeate which has passed through the filter support;
• and an outlet for concentrate which has not passed through the filter support;
• said filter support being in the form of a material of a tight textile construction of high pressure rating and low extensibility having two plies which are entangled together at parallel, spaced seams to form an integral array of side-by-side, continuous, separate tubes, said seams being strong enough to resist a relative pressure of 59 p.s.i. in said tubes, and said plies providing tube walls each of which has a flexural rigidity in at least one direction greater then zero and of not more than 2500 mg.cm according to British Standard 3356:
• 1961, said inlet being connected to the interior of said tubes whereby when said tubes are under the pressure of said feed, said walls provide an uninterrupted filter zone of substantial area which is restrained during filtration solely by tensile forces in said walls, substantial movement of said walls being possible in the direction at right angles to said walls when the pressures inside said tubes and outside said tubes are equal.

A plant for effluent treatment, and comprising a cross-flow filter comprising:

• means for mounting a filter support in position;
• a flexible filter support mounted by the mounting means;
• an inlet for leading feed to said filter support;
• an outlet for permeate which has passed through said filter support;
• and an outlet for concentrate which has not passed through said filter support;
• and wherein said filter support is in the form of a material having two plies which are connected together at parallel, spaced seams to form an integral array of side-by-side, continuous, separate tubes, said seams being strong enough to resist a relative pressure of about 59 p.s.i. in said tubes, and said plies providing tube walls each of which has a flexural rigidity in at least one direction greater than zero and of not more than 2500 mg.cm according to British Standard 3356:
• 1961, said inlet being connected to the interior of said tubes whereby when said tubes are under the pressure of said feed, said walls provide an uninterrupted filter zone of substantial area which is restrained during filtration solely by tensile forces in said walls, substantial movement of said walls being possible in the direction at right angles to said walls when the pressures inside said tubes and outside said tubes are equal.