A hydrodynamic method and apparatus are provided for forming tubular members useful in reverse-osmosis apparatus. A conventional film-forming liquid is forced through a tubular support by a pressurized column of gas to form a film of liquid on the inner wall of the tube. The liquid is then cured to solidify the film of liquid in tubular form. The disclosed hydrodynamic method and apparatus make possible an advantageous reverse-osmosis process and apparatus for recovering water of a low-salt concentration from saline water. Tubular membranes are hydrodynamically formed within a porous tubular support to form a porous structure, and saline water is supplied under pressure to the interior of the resulting structure to recover water having a low-salt concentration outside of the tubular support. When it becomes necessary to replace the tubular membrane, the supply of saline water is discontinued and a solvent is forced axially along the tubular membrane to dissolve it. Subsequently, the tubular membrane is hydrodynamically regenerated and the reverse-osmosis operation can be resumed.
Spirally coiled porous pipes with semi-permeable membrane lining are inserted in a rotatable vessel to subject solutions injected therein to centrifugally generated hydraulic pressure to perform reversed osmosis, dialysis or the creation of a membrane in situ.
A process for remotely fixing toxic dust, such as plutonium oxide, on the surfaces of a sealed cavity defining an airlock between two enclosures containing toxic material which are sealingly coupled to each other, so as to avoid contamination of the atmosphere upon uncoupling of the enclosures. The cavity is filled through an inlet zone with a solution of silicone grease in a solvent, such as freon, which is capable of wetting the surfaces of the cavity. The solvent is vaporized and evacuated from the cavity such that the silicone grease is deposited on the surfaces of the cavity to fix the toxic dust thereto.
A method and apparatus for achieving reverse osmosis, microfiltration, nanofiltration and ultrafiltration, produces Dean vortices against a membrane surface which is advantageously in a form of a wound helical membrane tube.
The invention is directed to a method of placing a semipermeable membrane on the surface of a small diameter bore formed in a rigid, porous support which comprises placing liquid membrane material in the bore, holding the support by the end in which the membrane material was inserted and rotating the support to force the material axially through the bore by centrifugal force.
A method of making a liquid purification module consists of (1) applying a finishing composition, comprising fine filler particles coated with a resinous material, to the interior circular cular bore walls of a membrane support module made of bonded, resin-coated coarse filler particles, to smooth irregularities in the bore walls, and then (2) drying the finishing composition to harden the finishing composition resinous material and bond it to the bore walls prior to applying semipermeable membranes inthe module bores.
