Showing papers on "Reverse osmosis published in 1968"
01 Sep 1968
TL;DR: The effectiveness of liquid membranes in increasing the permselectivity of the underlying gelatinous membrane in reverse osmosis increases with increasing hydrophilicity and is believed to be related to the capacities of the various surfactants for binding water and forming ordered and densely packed structures as discussed by the authors.
Abstract: A surfactant layer at the interface between a cellulose acetate membrane and a saline solution in reverse osmosis acts as a liquid membrane in series with the solid membrane gel. Partial liquid membranes exist below, and complete liquid membranes at, or above, the critical micelle concentration (CMC) of the surfactant feed additive. The effectiveness of liquid membranes in increasing the permselectivity of the underlying gelatinous membrane in reverse osmosis increases with increasing hydrophilicity and is believed to be related to the capacities of the various surfactants for binding water and forming ordered and densely packed structures.
75 citations
Patent•
24 May 1968TL;DR: In this paper, a novel water treating apparatus is disclosed having a unique capability of in combination treating and storing the treated water, supplying at instantaneous demand needs and at line pressure treated water and/or service water.
Abstract: A novel water treating apparatus is disclosed having a unique capability of in combination treating and storing the treated water, supplying at instantaneous demand needs and at line pressure treated water and/or service water and continuously replenishing the supply of treated water without the need for elaborate or special timing devices, switches, valving arrangements, etc. The apparatus is especially useful in softening or desalting water by reverse osmosis, electrodialysis and the like.
57 citations
Patent•
28 Jun 1968TL;DR: An improved reverse osmosis fabric has hollow fibers arranged in a predetermined pattern, either woven or nonwoven, that is relatively flexible yet provides a stable fabric configuration as discussed by the authors.
Abstract: An improved reverse osmosis fabric having hollow fibers arranged in a predetermined pattern, either woven or nonwoven, that is relatively flexible yet provides a stable fabric configuration
38 citations
Patent•
06 Dec 1968
TL;DR: In this paper, a flow control channel may be formed by a spiral groove in a face of one element maintained in contact with an adjoining face of another element, with the tank pressure relief connection at a point preferably from one-tenth to one-half the length of the channel measured from its brine release end.
Abstract: Pressure in a tank for storing water purified by a reverse osmosis unit is relieved at a predetermined proportionate pressure level by providing a connection from water in said tank to a restricted elongated flow channel used for control of brine release and pressure control in the reverse osmosis unit. Connection to the flow control channel is made at a point intermediate its ends and preferably at a point closer to the brine release end. The flow control channel may be formed by a spiral groove in a face of one element maintained in contact with an adjoining face of another element, with the tank pressure relief connection at a point preferably from one-tenth to onehalf the length of the channel measured from its brine release end.
21 citations
20 citations
Patent•
19 Mar 1968
TL;DR: In this article, aqueous effluent containing paint pigments and resins is separated by reverse osmosis into two streams which are of low and high concentration, respectively, with respect to pigment and resin.
Abstract: 1,163,351. Purification of aqueous paint effluents by reverse osmosis. PRESSED STEEL FISHER Ltd. 6 March, 1968 [22 March, 1967], No. 13432/67. Heading B1X. Aqueous effluent containing paint pigments and resins is separated by reverse osmosis into two streams which are of low and high concentration, respectively, with respect to pigment and resin, the stream of low concentration being re-used in the painting plant or discharged to waste, and the stream of high concentration being pumped through a filter bank and then returned to the reverse osmosis unit. If desirable, the filtered stream may be submitted to treatment in a second reverse osmosis unit whence the stream of low concentration is returned to the painting plant or to first reverse osmosis unit, while the stream of higher concentration is pumped hack to the filter bank.
18 citations
TL;DR: A mathematical model of a reverse osmosis water purification system that can be used in process optimization studies is developed in this paper, where a boundary layer flow model is used to relate water production rate to the operating pressure, Reynolds number, and membrane area cost equations that relate the capital and operating costs to the design variables are also developed.
17 citations
Patent•
28 Jun 1968TL;DR: A reverse osmosis module that minimizes concentration polarization and product fluid pressure drop effects by the use of a fabric having selected hollow fibers was proposed in this article, where one or more panels of the formed fabric were attached to and spirally wound around a tube and the spirally wrapped unit was inserted into a cylindrical pressure vessel so that a product fluid can be obtained from a feed fluid by the principle of reverse Osmosis.
Abstract: A reverse osmosis module that minimizes concentration polarization and product fluid pressure drop effects by the use of a fabric having selected hollow fibers. One or more panels of the formed fabric are attached to and spirally wound around a tube and the spirally wrapped unit is inserted into a cylindrical pressure vessel so that a product fluid can be obtained from a feed fluid by the principle of reverse osmosis.
TL;DR: In this article, the reverse osmosis separation data for the system sucrose-water using a number of Loeb-Sourirajan type porous cellulose acetate membranes is analyzed.
Abstract: : Analysis of the reverse osmosis separation data for the system sucrose-water using a number of Loeb-Sourirajan type porous cellulose acetate membranes shows that the solute transport parameter, D(AM)/K, for sucrose decreases with increase in its boundary concentration, X(A2). The plot of log D(AM)/K vs. X(A2) is a straight line, and this relationship is independent of the combination of feed concentration and flow rate used. The slope of the above straight line is a function of the operating pressure, and at a given operating pressure is essentially the same for all the membranes tested. For every film, a unique relationship exists between D(AM)/K for sodium chloride and the extrapolated value of D(AM)/K for sucrose at X(A2) = 0, giving rise to a new method of expressing membrane selectivity on a relative scale. The predictability of membrane performance for the reverse osmosis separation of sucrose in aqueous solution and the effect of membrane compaction on solute separation, from the initial specifications of the film given in terms of the pure water permeability constant and D(AM)/K for sodium chloride, are illustrated and discussed. (Author)
Patent•
22 Aug 1968TL;DR: An open pore tube for use with reverse osmosis water purification membranes is made of bonded resin coated filler particles as mentioned in this paper, which can be used to extract water from the water.
Abstract: An open pore tube for use with reverse osmosis water purification membranes is made of bonded resin coated filler particles.
TL;DR: A comparison of the net flux in reverse osmosis with the rate of tracer permeation in the same membrane provided positive evidence to show that hydrodynamic flow under pressure cannot account for the water flux through the membrane.
Abstract: The permeation of water and sodium chloride in cellulose acetate membranes has been examined over a wide range of concentration and pressure. The results obtained from reverse osmosis experiments have been used to evaluate relations derived on the assumption that permeation of both solution components takes place by diffusion down a concentration gradient in the membrane. With the aid of equilibrium and raidoactive tracer measurements, most of the deviations could be attributed to nonconstancy of the diffusion, and, especially, the distribution coefficients of water. A comparison of the net flux in reverse osmosis with the rate of tracer permeation in the same membrane provided positive evidence to show that hydrodynamic flow under pressure cannot account for the water flux through the membrane. Differences in the shape of the distribution isotherms for salt and water between solution and membrane provide an explanation for the high selectivity of cellulose acetate membranes in favor of water.
TL;DR: Water is separated from brines by a semipermeable membrane to create pressure which is transmitted by a water-immiscible liquid piston to a second chamber where it effects reverse osmosis.
Abstract: Water is separated from brines by a semipermeable membrane. Water flows by osmosis across the membrane into a sealed chamber where it creates pressure. This pressure is transmitted by a water-immiscible liquid piston to a second chamber where it effects reverse osmosis. Water-removal rates are calculated.
Patent•
29 Feb 1968TL;DR: The relative mobility of ions in cellulose-acetate membranes used for desalination of water by reverse osmosis depends strongly on the size of the hydrated ions as discussed by the authors.
Abstract: The relative mobility of ions in cellulose-acetate membranes used for desalination of water by reverse osmosis depends strongly on the size of the hydrated ions. The preferential exchange of ions by compacted clays shows a similar dependence. It is concluded that the same dependence must exist for the mobility of ions in compacted clays and shales acting as semi-permeable membranes. Qualitative results of the processes of osmosis and reverse osmosis through these materials thus should be similar to those obtained with the desalination membranes: modification of both chemical composition (ion ratios) and concentration of the solutions involved, and the occurrence of some flow-phenomena that are not in accordance with Darcy's law.
TL;DR: In this article, the cellulose acetate reverse osmosis membranes were stored in 20 different solutions for periods of time up to 45 months, where the pH of the storage solution was controlled to minimize hydrolysis, the samples showed good transport properties after storage.
TL;DR: The versatility of the new membranes also permits extensive experimental and theoretical studies of the physico-chemical characteristics of transport across simple and complex layers as mentioned in this paper. But the authors of this paper focus on the transport of polymeric materials.
Abstract: The advances which have been made in the synthesis of polymeric films have led to the development of several industrial processes based on transport through selective membranes. Desalination techniques based on electro-dialysis and on reverse osmosis, and methods for the isolation of valuable substances from gaseous or liquid mixtures by filtration across suitable films, are well-known examples. The versatility of the new membranes also permits extensive experimental and theoretical studies of the physico-chemical characteristics of transport across simple and complex layers.
Patent•
29 May 1968
TL;DR: In this paper, water is transferred between AQUEOUS solutions by contact with an AQUEous SALINE solUTION on one side of a SEMIPERMEABLE MEMBRANE, the other side of which is in contact with a SALINE solution of a POLYELECTROLYTE at a higher Osmotic pressure.
Abstract: WATER IS TRANSFERRED BETWEEN AQUEOUS SOLUTIONS BY CONTACTING AN AQUEOUS SALINE SOLUTION ON ONE SIDE OF A SEMIPERMEABLE MEMBRANE, THE OTHER SIDE OF WHICH IS IN CONTACT WITH AN AQUEOUS SOLUTION OF A POLYELECTROLYTE AT A HIGHER OSMOTIC PRESSURE, WHEREBY WATER DIFFUSES ACROSS THE MEMBRANE FROM THE SALINE SOLUTION TO THE POLYELECTROLYTE SOLUTION. D R A W I N G
Patent•
26 Jun 1968TL;DR: A fiber glass filament-wound porous tube for use in a reverse osmosis water purification system is made from multiple layers of resin impregnated continuous glass roving as discussed by the authors.
Abstract: A fiber glass filament-wound porous tube for use in a reverse osmosis water purification system is made from multiple layers of resin impregnated continuous glass roving. These tubes are fabricated either by an open weave helical filament winding technique or by adding to the impregnating resin certain amounts of blowing agent having a decomposition temperature slightly below or above the resin cure temperature.
Patent•
21 Feb 1968
TL;DR: In this paper, the authors describe the structure of a tubular support with the purpose of recovering water having a low salt concentration outside of the tube support, and a solvent is used to solve the problem.
Abstract: 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.
01 Jan 1968
TL;DR: In this article, the authors proposed a method to improve the quality of the data collected by the data collection system. But, the results showed that the system was ineffective in terms of data collection.
Abstract: 逆浸透圧法の基本的な量として塩の排除率,水の透過速度を定義し,排除率が塩の種類によって異なること,膜面には水の透過に伴って塩分濃度の高い境界層ができることを紹介した。半透膜について,現在用いられている含水性ジアセチルセルロース膜の製法とその特性を述べ,欠点である変形を防ぐ方法を論じ, トリアセチルセルロース膜, その他高分子膜の研究を紹介した。溶液の組成によっては多孔性の無機物質を半透膜の代わりに用いる可能性のあることも述べた。逆浸透圧法の装置としてアメリカの数社のそれぞれ特徴あるデザインを説明し,それらを使用した現場試験の結果にもふれた。本法により塩濃度の低い塩水の脱塩,パルプ廃液の濃縮が可能であることを例示し,前者についてはコスト計算の結果を示した。