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Description: A critical evaluation of data on the viscosity of aqueous sodium chloride solutions is presented. The literature was screened through October 1977, and a databank of evaluated data was established. Viscosity values were converted when necessary to units of centigrade, centipoise and molal concentration. The data were correlated with the aid of an empirical equation to facilitate interpolation and computer calculations. The result of the evaluation includes a table containing smoothed values for the viscosity of NaCl solutions to 150 C.
Date: October 1, 1977
Creator: Ozbek, H.; Fair, J.A. & Phillips, S.L.
Partner: UNT Libraries Government Documents Department


Description: The activity coefficients of HCl and NaCl in HCl--NaCl mixtures were computed from literature data. The calculations are based on the observation that at constant ionic strength and temperature the logarithm of the activity coefficient of HCi in HCl--NaCl mixtures varies linearly with NaCl concentration. (auth)
Date: July 29, 1963
Creator: Lietzke, M.H. & Stoughton, R.W.
Partner: UNT Libraries Government Documents Department

Laboratory Characterization of Mechanical and Permeability Properties of Dynamically Compacted Crushed Salt

Description: The U. S. Department of Energy plans to dispose of transuranic wastes at the Waste Isolation Pilot Plant (WIPP), a geologic repository located at a depth of about 655 meters. The WIPP underground facility is located in the bedded salt of the Salado Formation. Access to the facility is provided through vertical shafts, which will be sealed after decommissioning to limit the release of hazardous waste from the repository and to limit flow into the facility. Because limited data are available to characterize the properties of dynamically compacted crushed salt, Sandia National Laboratories authorized RE/SPEC to perform additional tests on specimens of dynamically compacted crushed salt. These included shear consolidation creep, permeability, and constant strain-rate triaxial compression tests. A limited number of samples obtained from the large compacted mass were available for use in the testing program. Thus, additional tests were performed on samples that were prepared on a smaller scale device in the RE/SPEC laboratory using a dynamic-compaction procedure based on the full-scale construction technique. The laboratory results were expected to (1) illuminate the phenomenology of crushed-salt deformation behavior and (2) add test results to a small preexisting database for purposes of estimating parameters in a crushed-salt constitutive model. The candidate constitutive model for dynamically compacted crushed salt was refined in parallel with this laboratory testing.
Date: February 1, 1999
Creator: Hansen, F.D.; Mellegard, K.D. & Pfeifle, T.W.
Partner: UNT Libraries Government Documents Department


Description: An investigation was made to determine the stress field in the salt dome and the stress concentrations on the surface of the small (12-ft diameter) sphere. For the most part, the apparatus and techniques used in the investigation are new and have not been described in other reports. Therefore the theory, concepts, apparatus, and some of the lists made to determine the reproducibility of the apparatus are described briefly. (W.L.H.)
Date: July 29, 1960
Creator: Merrill, R.H.
Partner: UNT Libraries Government Documents Department

Electrostatic Modeling of Vacuum Insulator Triple Junctions

Description: A comprehensive matrix of 60 tests was designed to explore the effect of calcium chloride vs. sodium chloride and the ratio R of nitrate concentration over chloride concentration on the repassivation potential of Alloy 22. Tests were conducted using the cyclic potentiodynamic polarization (CPP) technique at 75 C and at 90 C. Results show that at a ratio R of 0.18 and higher nitrate was able to inhibit the crevice corrosion in Alloy 22 induced by chloride. Current results fail to show in a consistent way a different effect on the repassivation potential of Alloy 22 for calcium chloride solutions than for sodium chloride solutions.
Date: August 13, 2007
Creator: Tully, L. K.; White, A. D.; Goerz, D. A.; Javedani, J. B. & Houck, T. L.
Partner: UNT Libraries Government Documents Department

Evaluation of Reservoir Wettability and its Effect on Oil Recovery.

Description: This project has three main goals. The first is to achieve improved understanding of the surface and interfacial properties of crude oils and their interactions with mineral surfaces. The second goal is to apply the results of surface studies to improved predictions of oil production in laboratory experiments. Finally, we aim to use the results of this research to recommend ways to improve oil recovery by waterflooding. In order to achieve these goals, the mechanisms of wetting alteration must be explained. We propose a methodology for studying those mechanisms on mineral surfaces, then applying the results to prediction and observation of wetting alteration in porous media. Improved understanding of the underlying mechanisms will show when and how wettability in the reservoir can be altered and under what circumstances that alteration would be beneficial in terms of increased production of oil. Crude Oil/Brine/Solid Interactions The interactions between crude oils, brines, and solid surfaces have been studied using a variety of core materials as well as in two-dimensional micromodels of interconnecting pores and throats. In the work reported this quarter, these same interactions have been applied to create mixed-wet conditions in a very simple model porous material, namely square glass tubes which have the advantage of permitting dual occupancy by both wetting and nonwetting phases simultaneously. The interactions between crude oil samples from Prudhoe Bay have been studied on a variety of surfaces. Figure 1 outlines the regions of stable and unstable brine compositions with A-93, a sample from Prudhoe Bay, and glass surfaces. A brine with pH 8 and 1 M concentration of NaCl produces a stable water film between glass and A-93 crude oil. If the brine has pH 4 and 0.01M NaCl, thin films of water are unstable and oil contacts the glass. Between these extremes is a wide ...
Date: October 1, 1997
Creator: Buckley, J.S.
Partner: UNT Libraries Government Documents Department

Thermodynamics and kinetics of ion speciation in supercritical aqueous solutions: A molecular based study

Description: Molecular simulation of infinitely dilute NaCl aqueous solutions are performed to study the Na{sup +}/Cl{sup -} ion pairing in a polarizable and a nonpolarizable solvent at supercritical conditions. The Simple Point Charge, Pettitt-Rossky, and Fumi-Tosi models for the water-water, ion-water, and ion-ion interactions are used in determining the degree of dissociation, its temperature and density dependence, and the kinetics of the interconversion between ion-pair configurations in a nonpolarizable medium. To assess the effect of the solvent polarizability on the stability of the ion-pair configurations, we replace the Simple Point Charge by the Polarizable Point Charge water model and determine the anion-cation potential of mean force at T{sub r}=1.20 and {rho}{sub r}=1.5.
Date: May 1, 1997
Creator: Chialvo, A.A.; Cummings, P.T.; Simonson, J.M. & Mesmer, R.E.
Partner: UNT Libraries Government Documents Department

Double-Diffusive Finger Convection: Flow Field Evolution in a Hele-Shaw Cell

Description: Double-diffusive finger convection is a hydrodynamic instability that can occur when two components with different diffusivities are oppositely stratified with respect to the fluid density gradient as a critical condition is exceeded. Laboratory experiments were designed using sodium chloride and sucrose solutions in a Hele-Shaw cell. A high resolution, full field, light transmission technique was used to study the development of the instability. The initial buoyancy ratio (R{sub p}), which is a ratio of fluid density contributions by the two solutes, was varied systematically in the experiments so that the range of parameter space spanned conditions that were nearly stable (R{sub p} = 2.8) to those that were moderately unstable (R{sub p} = 1.4). In systems of low R{sub p}, fingers develop within several minutes, merge with adjacent fingers, form conduits, and stall before newer-generated fingers travel through the conduits and continue the process. Solute fluxes in low R{sub p} systems quickly reach steady state and are on the order of 10{sup {minus}6} m{sup 2} sec{sup {minus}1}. In the higher R{sub p} experiments, fingers are slower to evolve and do not interact as dynamically as in the lower R{sub p} systems. Our experiment with initial R{sub p} = 2.8 exhibited flux on the order of that expected for a similar diffusive system (i.e., 10{sup {minus}7} m{sup 2} sec{sup {minus}1}), although the structures were very different than the pattern of transport expected in a diffusing system. Mass flux decayed as t{sup 1/2} in two experiments each with initial R{sub p} = 2.4 and 2.8.
Date: December 21, 2000
Creator: Cooper, Clay A.; Glass, Robert J., Jr. & Tyler, Scott W.
Partner: UNT Libraries Government Documents Department

Decomposition Studies of Tetraphenylborate Slurries

Description: This report details the decomposition of aqueous (K,Na) slurries in concentrated salt solutions using a more complete candidate catalyst recipe, extended testing temperatures (40-70 degrees C) and test durations of approximately 1500 hours (9 weeks). This study uses recently developed High-Pressure Liquid Chromatography (HPLC) methods for analysis of tetraphenylborate (TPB-), triphenylborane (3PB) and diphenylborinic acid (2PB). All of the present tests involve non-radioactive simulants and do not include investigations of radiolysis effects.
Date: May 6, 1997
Creator: Crawford, C.L.
Partner: UNT Libraries Government Documents Department

Estimating the hydrogen ion concentration in concentrated NaCl and Na{sub 2}SO{sub 4} electrolytes

Description: Combination glass electrodes were tested for determining H{sup +} concentrations in concentrated pure and mixed NaCl and Na{sub 2}SO{sub 4} solutions, as well as natural brine systems. NaCl, Na{sub 2}SO{sub 4}, and mixtures of NaCl and Na{sub 2}SO{sub 4} solutions were analyzed. Correction factors for estimating pC{sub H}{sup +} (negative logarithm of H{sup +} concentration) were determined from measured/observed pH values. Required Gran-type titrations were done with HCl and/or NaOH. The titration method is described and a step-by-step procedure provided; it has been used previously for determining pC{sub H}{sup +} values of synthetic chloride-dominated brines. Precautions are required to determine correction factors for electrolytes that react with H{sup +} or OH{sup {minus}} [sulfate brines for titration with acid; magnesium brines for titration with base because of precipitation of Mg(OH)2]. Correction factors A (pC{sub H}{sup +} = pH{sub ob} + A) from HCl titrations were similar to those from NaOH titrations where the concentration of free H{sup +} was calculated using a thermodynamic model. These values should be applicable to solns with a very large range in measured pH values (2 to 12). Because a large number of solns were titrated with HCl and the A values are similar for HCl and NaOH titrations, the A values for NaCl and Na2SO4 solns were fit as a function of molality to allow extrapolation. For NaCl solns 0 to 6.0 M, A can be obtained by multiplying the molality by 0.159. For Na2SO4 solns 0 to 2.0 M, the values of A can be obtained from (0.221 {minus} 0.549X + 0.201X{sup 2}), where X is the molality of Na{sub 2}SO{sub 4}. Orion-Ross electrode evaluations indicated that the A values did not differ significantly for different electrodes. Results suggest that the data in this report can be used to estimate A values for different ...
Date: June 1, 1995
Creator: Rai, D.; Felmy, A.R.; Juracich, S.P. & Rao, F.
Partner: UNT Libraries Government Documents Department

Corrosion Behavior of Titanium Grade 7 in Fluoride-Containing NaCl Brines

Description: Titanium Grade 7 (UNS R52400) is a titanium-based alloy with 0.12-0.25% Pd. The addition of the small amount of palladium is to ennoble the corrosion potential of Ti, thus improving the corrosion resistance of titanium in reducing environments. In most aqueous environments, Ti and Ti alloys demonstrate excellent corrosion resistance due to the protective oxide film that forms spontaneously and remains stable on the surface. However, Ti and Ti alloys are susceptible to corrosion in fluoride-containing environments due to the formation of complexes such as TiF{sub 6}{sup 2-} and TiF{sub 6}{sup 3-}, which are stable and soluble in electrolyte solutions. Without the presence of fluoride, only slight effects from [Cl{sup -}], pH and temperature have been reported [1]. It has been reported that the kinetics of passive corrosion of titanium in neutral solutions and controlled by the migration of the defects in the oxide across the surface film [2]. Thus, the increase in thickness and improvement in film properties, by thermal oxidation, would lead to a significant decrease in the susceptibility to film breakdown and in the passive corrosion rate. This report summarizes recent experiment results in studies of the environmental influence on the corrosion behavior of Titanium Grade 7 (Ti-7) in NaCl brines containing fluoride. The environmental factors to be studied include temperature, pH, chloride and fluoride concentration. This report also includes the effects of oxide film, formed during an anneal treatment, on the corrosion behavior of Ti-7. Polarization measurement techniques including potentiodynamic and potentiostatic scans were use3d to characterize corrosion kinetics and susceptibility. Due to the unique alloying in Titanium Grade 7, the long-term corrosion behavior is heavily influenced by the surface enrichment of Pd. Use of electrochemical impedance spectroscopy in conjunction with a potentiostatic scan will reveal the transformation in the corrosion behavior as a function of ...
Date: May 18, 2004
Partner: UNT Libraries Government Documents Department

Extrusion of I and E `O` size tubing to evaluate reduction in extruded O.D. and the use of pressed salt follower blocks: Experiment Number U-21

Description: The object of this experiment was to extrude normal uranium hollow billets to I and E `O` size tubing with reduced extruded O.D. and also to evaluate the use of pressed salt follower blocks. Pressed salt (NaCl) follower blocks under various conditions of pre-heat temperature were compared with the standard graphite at 800 F. Even though some yield reduction results, it was concluded that pressed salt follower blocks at 300 F represent a substantial cost reduction due to the extreme price differential of the two perishable items. Extruded O.D.`s of .020 inch and .040 inch less than the standard (nominal) 1.50 inch represent no gain in yield due to the sharp increase in machined slug rejects for O.D. defects.
Date: January 31, 1961
Creator: Puterbaugh, J.F.
Partner: UNT Libraries Government Documents Department

Tolerance Test of Eisenia Fetida for Sodium Chloride

Description: Saltwater spills that make soil excessively saline often occur at petroleum exploration and production (E&P) sites and are ecologically damaging. Brine scars appear when produced water from an E&P site is spilled onto surrounding soil, causing loss of vegetation and subsequent soil erosion. Revegetating lands damaged by brine water can be difficult. The research reported here considers earthworms as a bioremedial treatment for increasing the salt mobility in this soil and encouraging plant growth and a healthy balance of soil nutrients. To determine the practical application of earthworms to remediate brine-contaminated soil, a 17-d test was conducted to establish salt tolerance levels for the common compost earthworm (Eisenia fetida) and relate those levels to soil salinity at brine-spill sites. Soil samples were amended with sodium chloride in concentrations ranging from 1 to 15 g/kg, which represent contamination levels at some spill sites. The survival rate of the earthworms was near 90% in all tested concentrations. Also, reproduction was noted in a number of the lower-concentration test replicates but absent above the 3-g/kg concentrations. Information gathered in this investigation can be used as reference in further studies of the tolerance of earthworms to salty soils, as results suggest that E. fetida is a good candidate to enhance remediation at brine-damaged sites.
Date: January 1, 2003
Creator: Kerr, M. & Stewart, A.J.
Partner: UNT Libraries Government Documents Department

Re-Evaluation of Chemical Potential of Imperial Irrigation District Well No. 1

Description: The chemical potential of the brine from I.I.D. Well No. 1 was evaluated and reported in Rogers Engineering Coo, Inc. March 1962 Flow Test Report. This evaluation considered only the recovery of sodium chloride, as the prime salable product and alternately as the raw material for conversion to salable chlorine and caustic. Both cases showed low net revenue relative to the estimated capital investment required. The subsequent three month well flow test indicates continued production of a consistent type brine can be expected from this well. Based on the flow and composition data established during this test period, chemical production potential has been examined. The separation and sale of high quality potassium chloride appears attractive. Attached are sketches of each of the two production schemes considered with estimates of capital and operating costs and revenue.
Date: April 1, 1963
Partner: UNT Libraries Government Documents Department

Repassivation Potential of Alloy 22 in Sodium and Calcium Chloride Brines

Description: A comprehensive matrix of 60 tests was designed to explore the effect of calcium chloride vs. sodium chloride and the ratio R of nitrate concentration over chloride concentration on the repassivation potential of Alloy 22. Tests were conducted using the cyclic potentiodynamic polarization (CPP) technique at 75 C and at 90 C. Results show that at a ratio R of 0.18 and higher nitrate was able to inhibit the crevice corrosion in Alloy 22 induced by chloride. Current results fail to show in a consistent way a different effect on the repassivation potential of Alloy 22 for calcium chloride solutions than for sodium chloride solutions.
Date: August 11, 2007
Creator: Rebak, R B; Ilevbare, G O & Carranza, R M
Partner: UNT Libraries Government Documents Department

Long Term Corrosion Potential and Corrosion Rate of Creviced Alloy 22 in Chloride Plus Nitrate Brines

Description: Alloy 22 is a nickel base alloy highly resistant to all forms of corrosion. In conditions where tight crevices exist in hot chloride containing solutions and at anodic potentials, Alloy 22 may suffer crevice corrosion, a form of localized attack. The occurrence (or not) of crevice corrosion in a given environment (e.g. salt concentration and temperature), is governed by the values of the critical potential (E{sub crit}) for crevice corrosion and the corrosion potential (E{sub corr}) that the alloy may establish in the studied environment. If E{sub corr} is equal or higher than E{sub crit}, crevice corrosion may be expected. In addition, it is generally accepted that as Alloy 22 becomes passive in a certain environment, its E{sub corr} increases and its corrosion rate (CR) decreases. This paper discusses the evolution of E{sub corr} and corrosion rate (CR) of creviced Alloy 22 specimens in six different mixtures of sodium chloride (NaCl) and potassium nitrate (KNO{sub 3}) at 100 C. The effect of immersion time on the value of E{sub crit} was also determined. Two types of specimens were used, polished as-welded (ASW) and as-welded plus solution heat-treated (ASW+SHT). The latter contained the black annealing oxide film on the surface. Results show that, as the immersion time increases, E{sub corr} increased and the CR decreased. Even for highly concentrated brine solutions at 100 C the CR was < 30 nm/year after more than 250 days immersion. Some of the exposed specimens (mainly the SHT specimens) suffered crevice corrosion at the open circuit potential in the naturally aerated brines. Immersion times of over 250 days did not reduce the resistance of Alloy 22 to localized corrosion.
Date: November 5, 2005
Creator: Evans, K J; Stuart, M L; Etien, R A; Hust, G A; Estill, J C & Rebak, R B
Partner: UNT Libraries Government Documents Department