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The Mechanism of Desalination by Reverse Osmosis

Description: From Introduction: " With the ultimate objective of improving the process, a study of the mechanism(s) of material transport across the membrane was undertaken; the OSW sponsored a fundamental program of investigation of the Reverse Osmosis Process. Following a brief review of the results of the first year's investigations, the body of this report will cover the accomplishments of the second year's effort."
Date: unknown
Creator: Keilin, B.
Partner: UNT Libraries Government Documents Department

Operation of Reverse Osmosis Pilot Plants

Description: From Introduction: "This report includes the sixth segment of a continuing effort begun early in 1963. Purpose of the work is the scale-up of reverse osmosis from a laboratory curiosity to an economical system for the production of potable water from salty feeds."
Date: August 1968
Creator: DeHaven, C. G.; Jarvis, M. A. & Wunderlich, C. R.
Partner: UNT Libraries Government Documents Department

Process and Configuration Development for Tubular Reverse Osmosis Units

Description: From Introduction and Summary: "The overall objective of this program was to develop an economical tubular reverse osmosis system for desalination of brackish water. Major emphasis was placed on the following aspects of the system. The work accomplished is summarized in the following paragraphs."
Date: May 1969
Creator: Fluke, G. A.
Partner: UNT Libraries Government Documents Department

A New Design Concept for Reverse Osmosis Membrane Cells

Description: From Introduction: "A new concept, that of lateral permeation of product water through a porous substrate, is the basis for both the cost reduction study of plate-and-frame reverse osmosis units and the study of field replacement of membrane and is therefore the subject of the development studies encompassed by this report."
Date: May 1969
Creator: Fluke, G. A.
Partner: UNT Libraries Government Documents Department

Large Reverse Osmosis System Technology and Module Development

Description: From Introduction: "This is the final report on a program of reverse osmosis research conducted for the Office of Saline Water, U.S. Department of the Interior, under Contract 14-01-0001-929. The purpose of the program was the development of larger spiral-wound reverse osmosis modules for economical application in large reverse osmosis systems."
Date: June 1968
Creator: Riedinger, A. B.; Laughlin, J. K. & Sudak, R. G.
Partner: UNT Libraries Government Documents Department

Reverse Osmosis for Water Desalination

Description: Report issued by the Office of Saline Water over studies conducted on the reverse-osmosis program. The methods of desalination through osmosis are discussed. This report includes tables, illustrations, and photographs.
Date: May 22, 1964
Creator: Lonsdale, H. K.; Merten, U.; Riley, R. L.; Vos, K. D. & Westmoreland, J. C.
Partner: UNT Libraries Government Documents Department

Development of Water Purification Systems Based on Reverse Osmosis

Description: Report demonstrating the concept of a small and disposable reverse-osmosis cartridge. Research includes "1) a search for suitable membrane supporting structures and materials during which the hydrodynamic characteristics of a number of potential materials were evaluated, 2) the evaluation of reverse-osmosis membranes cast directly on support materials and on reinforcing materials, and 3) the design, fabrication and testing of a small reverse-osmosis cartridge" (p. 1).
Date: April 1969
Creator: Ellington, R. C.
Partner: UNT Libraries Government Documents Department

Effects of Manufacturing Variables and the Development of Replaceable Membrane Elements for Brackish Water Tubular Reverse Osmosis Systems

Description: Report describing the development of a reliable means to cast brackish water desalination membranes, the quality control of membrane-support elements, and the development of replaceable membrane elements.
Date: May 1971
Creator: Blevitt, R.; Hartupee, R. H. & Marks, M.
Partner: UNT Libraries Government Documents Department

An Osmoreceptive Zone Around the Nucleus Circularis

Description: The nucleus circularis has been linked to a role in regulating osmotic thirst but evidence has also shown that full bilateral destruction of the nucleus circularis was not necessary to achieve a deficit in drinking behavior after an osmotic challenge. The present study attempted to answer two primary research questions. The first question was whether osmoreceptive cells existed around the nucleus circularis in a homogeneous fashion or if these cells existed in a structured fashion stretching from the nucleus circularis forward. The second question was whether animals with lesions of the nucleus circularis and the surrounding areas were different in normal daily water intake than animals with no lesions. The first question was approached by lesioning the nucleus circularis, the area one millimeter anterior to the nucleus circularis, one millimeter posterior to the nucleus circularis, one half of a millimeter medial to the nucleus circularis and using a sham group which had the electrode passed through the brain to a spot one millimeter above the nucleus circularis but passing no current. All animals were then given an osmotic challenge which consisted of half of each group with an injection of hypertonic saline while the other half of each group was given isotonic saline. After a five-day recovery period, the injection procedure was reversed. Water consumption on each test day was measured at ten-minute intervals for one hour. Difference scores were then computed by subtracting the amount of water consumed after hypertonic saline injection from the amount of water consumed after isotonic saline injection. The difference scores were then used in an analysis of variance which revealed a significant difference between groups. A subsequent post hoc test showed that the nucleus circularis group was different from all other groups except for the anterior lesion group which showed a trend in the ...
Date: August 1985
Creator: Wallace, Forrest Layne
Partner: UNT Libraries

Membrane Oxygen Enrichment Cost and Application Evaluation

Description: A separation process, similar to the reverse osmosis membrane process for the desalination of water, can be used for the separation and enrichment of multi-component gas streams. The development of new processing methods and modular packing systems together with advanced commercialization of desalination systems now makes similar processes for gas separation appear feasible and economical. Composite membranes have been developed that are both thin enough to provide a large gas flow and strong enough to withstand the driving pressure of the incoming gas. This is done by depositing a polymer on the finely porous surface of a fabric-reinforced supporting membrane. The resulting material is then formed into a spiral-wound element that provides a large amount of membrane area in a small volume. Laboratory experiments using gas separation membranes by Fluid Systems Division of UOP and by General Electric Company have established the technical feasibility of using such membranes to produce oxygen-enriched air. A preliminary analysis of membrane oxygen enrichment economics was prepared by the Fluid System Division of UOP which shows that oxygen enrichment could be profitable for combustion systems up to 100 tons of oxygen per day. A supporting economic study made by Econergy Associates reaffirms the positive economic potential for a 1000-ton/day, 30% oxygen enrichment plant.
Date: March 1979
Creator: Fischer, Jack & Burnett, Lowell J.
Partner: UNT Libraries Government Documents Department

Initial cost analysis of a desalination process utilizing hydrotalcite and permutite for ion sequestration.

Description: An initial cost analysis of a proposed desalination process was performed. The proposed process utilizes tailored inorganic ion exchangers, hydrotalcite and permutite, to sequester anions and cations from a brackish water solution. Three different process scenarios were considered: (1) disposal of the spent exchangers as dry waste (2) conventional chemical regeneration, and (3) acid regeneration of permutite coupled with thermal (550 C) regeneration of hydrotalcite. Disposal of the resin and conventional regeneration are not viable options from an economic standpoint. Applying limited data and optimistic assumptions to the third scenario yielded an estimate of $2.34/kgal of product water. Published values for applying conventional reverse osmosis to similar water streams range from $0.70 to $2.65/kgal. Consistent with these baseline values, the Water Treatment Estimation Routine, WaTER, developed by the United States Department of the Interior, Bureau of Reclamation produced a cost estimate of $1.16/kgal for brackish water reverse osmosis.
Date: December 1, 2004
Creator: Miller, James Edward & Evans, Lindsey R.
Partner: UNT Libraries Government Documents Department

Saltstone Osmotic Pressure

Description: Recent research into the moisture retention properties of saltstone suggest that osmotic pressure may play a potentially significant role in contaminant transport (Dixon et al., 2009 and Dixon, 2011). The Savannah River Remediation Closure and Disposal Assessments Group requested the Savannah River National Laboratory (SRNL) to conduct a literature search on osmotic potential as it relates to contaminant transport and to develop a conceptual model of saltstone that incorporates osmotic potential. This report presents the findings of the literature review and presents a conceptual model for saltstone that incorporates osmotic potential. The task was requested through Task Technical Request HLW-SSF-TTR-2013-0004. Simulated saltstone typically has very low permeability (Dixon et al. 2008) and pore water that contains a large concentration of dissolved salts (Flach and Smith 2013). Pore water in simulated saltstone has a high salt concentration relative to pore water in concrete and groundwater. This contrast in salt concentration can generate high osmotic pressures if simulated saltstone has the properties of a semipermeable membrane. Estimates of osmotic pressure using results from the analysis of pore water collected from simulated saltstone show that an osmotic pressure up to 2790 psig could be generated within the saltstone. Most semi-permeable materials are non-ideal and have an osmotic efficiency <1 and as a result actual osmotic pressures are less than theoretical pressures. Observations from laboratory tests of simulated saltstone indicate that it may exhibit the behavior of a semi-permeable membrane. After several weeks of back pressure saturation in a flexible wall permeameter (FWP) the membrane containing a simulated saltstone sample appeared to have bubbles underneath it. Upon removal from the FWP the specimen was examined and it was determined that the bubbles were due to liquid that had accumulated between the membrane and the sample. One possible explanation for the accumulation of solution between ...
Date: September 23, 2013
Creator: Nichols, Ralph L. & Dixon, Kenneth L.
Partner: UNT Libraries Government Documents Department

Mixing in polymeric microfluidic devices.

Description: This SAND report describes progress made during a Sandia National Laboratories sponsored graduate fellowship. The fellowship was funded through an LDRD proposal. The goal of this project is development and characterization of mixing strategies for polymeric microfluidic devices. The mixing strategies under investigation include electroosmotic flow focusing, hydrodynamic focusing, physical constrictions and porous polymer monoliths. For electroosmotic flow focusing, simulations were performed to determine the effect of electroosmotic flow in a microchannel with heterogeneous surface potential. The heterogeneous surface potential caused recirculations to form within the microchannel. These recirculations could then be used to restrict two mixing streams and reduce the characteristic diffusion length. Maximum mixing occurred when the ratio of the mixing region surface potential to the average channel surface potential was made large in magnitude and negative in sign, and when the ratio of the characteristic convection time to the characteristic diffusion time was minimized. Based on these results, experiments were performed to evaluate the manipulation of surface potential using living-radical photopolymerization. The material chosen to manipulate typically exhibits a negative surface potential. Using living-radical surface grafting, a positive surface potential was produced using 2-(Dimethylamino)ethyl methacrylate and a neutral surface was produced using a poly(ethylene glycol) surface graft. Simulations investigating hydrodynamic focusing were also performed. For this technique, mixing is enhanced by using a tertiary fluid stream to constrict the two mixing streams and reduce the characteristic diffusion length. Maximum mixing occurred when the ratio of the tertiary flow stream flow-rate to the mixing streams flow-rate was maximized. Also, like the electroosmotic focusing mixer, mixing was also maximized when the ratio of the characteristic convection time to the characteristic diffusion time was minimized. Physical constrictions were investigated through simulations. The results show that the maximum mixing occurs when the height of the mixing region is minimized. Finally, experiments ...
Date: April 1, 2006
Creator: Schunk, Peter Randall; Sun, Amy Cha-Tien; Davis, Robert H. (University of Colorado at Boulder, Boulder, CO) & Brotherton, Christopher M. (University of Colorado at Boulder, Boulder, CO)
Partner: UNT Libraries Government Documents Department

Some Results Bearing on the Value of Improvements of Membranes for Reverse Osmosis

Description: This analysis evaluates the potential economic benefits that could result from the improvements in the permeability of membranes for reverse osmosis. The discussion provides a simple model of the operation of a reverse osmosis plant. It examines the change in the operation that might result from improvements in the membrane and computes the cost of water as a function of the membrane permeability.
Date: March 8, 2006
Creator: Lamont, A
Partner: UNT Libraries Government Documents Department