Inside-to-outside flow filter tube and method of using same

A method of filtering a fluid stream, which method comprises:

• (a) introducing the fluid stream to be filtered into the interior of an inside-to-outside flow filter tube, which filter tube comprises:
• (i) a plurality of randomly disposed, nonwoven glass fibers having a diameter of from about 0.001 to 10 microns, and having interstices therebetween, the fibers bonded together into a self-supporting filter tube by a bonding agent at the junction of the fiber crossover points to form a filter tube wall, and
• (ii) an open scrim sheet material embedded within said filter tube wall, with no scrim material extending to the external filter tube wall, the scrim material extending generally the length of the filter tube and at least about one and one-half revolutions about the tube diameter, the scrim material formed into a generally noncontacting helical scroll, with a layer of glass fibers of selected depth separating each convoluted layer of scrim material, the glass fibers bonded cooperatively with and through the scrim material by the bonding agent, to form a continuous, integrally bonded, filter tube wall means of the glass fibers;
• and
• (b) filtering the fluid stream by passage through the porous filter tube wall of the filter tube, said filter tube having an average burst strength of greater than 52 P.S.I.

A method of filtering a fluid stream, which method comprises:

• (a) introducing the fluid stream to be filtered into the interior of an inside-to-outside flow filter tube, which filter tube comprises:
• (i) a plurality of randomly disposed, nonwoven glass fibers having a diameter of from about 0.01 to 8 microns, and having interstices therebetween, the fibers bonded together into a self-supporting filter tube by a hardened resin-bonding agent at the junction of the fiber crossover points to form a filter tube wall, and
• (ii) an open scrim sheet material of glass fibers having openings of about 1/4 to 1 inch and embedded within said filter tube wall, with no scrim material extending to the external filter tube wall, the scrim material extending generally the length of the filter tube and from about one and one-half to five revolutions about the tube diameter, the scrim material formed into a generally noncontacting helical scroll, with a layer of glass fibers of selected depth separating each convoluted layer of scrim material, the glass fibers bonded cooperatively with and through the scrim material by the bonding agent, to form a continuous, integrally bonded, filter tube wall of the glass fibers;
• and
• (b) filtering the fluid stream by passage through the porous filter tube wall of the filter tube, said filter tube having an average burst strength of greater than 52 P.S.I.