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Phosphate-bonded glass cements for geothermal wells. Final report

Description: Calcium aluminosilicate glasses were found to react with phosphoric acid in three ways depending upon silica content. Above 55% SiO/sub 2/ they are insoluble while below 50% they dissolve readily. The transition compositions release calcium and aluminum ions and a silica gel phase replaces the glass. Activation energies in the order of 10 kcal/mole are associated with the dissolution. Equilibrium studies in the systems CaO-P/sub 2/O/sub 5/-H/sub 2/O, Al/sub 2/O/sub 3/-P/sub 2/O/sub 5/-H/sub 2/O… more
Date: September 1, 1979
Creator: Rockett, T.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evidence of former higher temperatures from alteration minerals, Bostic 1-A well, Mountain Home, Idaho

Description: Cuttings from the silicic volcanics in the Bostic 1-A well near Mountain Home, Idaho have been examined petrographically with the assistance of x-ray diffraction and electron microprobe analyses. Results indicate that these rocks have been subjected to much higher temperatures than were observed in the well in 1974, when a static temperature log was run. It is not known to what extent the alternation may be due to greater depth of burial in the past, or whether it resulted from an early hydroth… more
Date: January 1, 1982
Creator: Arney, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Removal of silica from Raft River geothermal water

Description: Lack of sufficient quantities of clean surface or near-surface water at Raft River for cooling purposes dictates that cooled geothermal fluid, effluent from the Raft River 5 MW(e) Pilot Power Plant, must also be used as condenser coolant. Prior testing revealed that a water-treatment system would be required to reduce silica and calcium concentrations of the cooling fluid. The water-treatment system specified was to use dolomitic lime for both pH adjustment and source of magnesium. The dolomiti… more
Date: June 1, 1980
Creator: Suciu, D. F. & Miller, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alternate materials of construction for geothermal applications. Progress report No. 14, July--September 1977

Description: A program to determine if non-metallic materials such as polymers, concrete polymer composites, and refractory cements can be utilized as materials of construction in geothermal processes is in progress. To date, several high temperature polymer concrete systems have been formulated, laboratory and field tests performed in brine, flashing brine, and steam at temperatures up to 260/sup 0/C (500/sup 0/F), and economic studies started. Laboratory data for exposure times > 2 years are available. Re… more
Date: September 1, 1977
Creator: Kukacka, L. E.; Fontana, J.; Zeldin, A.; Sugama, T.; Horn, W.; Carciello, N. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Damage to fused silica windows while under simultaneous exposure to flowing solvents and laser radiation and 308nm

Description: This paper reports the results of a study to determine the degrading effects of flowing dye solvents on the laser damage threshold of fused-silica windows at 308nm. Thresholds were measured at the SiO/sub 2/solvent interface in a test cell. Bare SiO/sub 2/ tested in air at 308nm (20ns) typically exhibits a threshold ranging from 4 to 10 Jcm/sup 2/; with the solvent cyclohexane in contact, a threshold as low as 0.3 Jcm/sup 2/ was measured. The damage data indicate that window lifetime (number of… more
Date: January 1, 1987
Creator: Mauro, B. R.; Foltyn, S. R. & Sanders, V. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

Description: An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Conditioning of geothermal brine effluents for injection: use of coagulants

Description: The use of various chemical coagulants and flocculants with spent geothermal brine for enhancing the removal of colloidal solids prior to injection was studied. Brine at 80 to 85/sup 0/C was obtained from the injection line of the SDG and E/DOE Geothermal Loop Experimental Facility during a period of operation with Magmamax No. 1 Fluid. The solids consist primarily of an iron-rich amorphous silica and heavy metal sulfides, principally lead. Standard jar testing equipment was used to carry out t… more
Date: February 1, 1978
Creator: Quong, R.; Shoepflin, F. & Stout, N.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of brine treatment. Final report

Description: Available information pertinent to the treatment of geothermal brines was collected by literature search and then evaluated and summarized for use by the electric utility and geothermal industries. The information was screened from the geothermal, oil and gas, wastewater disposal, and boiler water treatment industries. The current state of knowledge and methodology concerning the treatment of geothermal brines to control scaling and corrosion in geothermal electric power production was assessed… more
Date: November 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dynamic performance of packed-bed dehumidifiers: experimental results from the SERI desiccant test loop

Description: Discussed are the design and construction of a desiccant test loop and results of tests with a silica-gel-packed bed. The test loop consists of two centrifugal fans, two duct heaters, a steam humidifier, 24.4m (80 ft) of 30-cm (12-in.) circular duct, instrumentation, and a test section. The loop is capable of testing adsorption and desorption modes at flow rates up to 0.340 kg/s (600 scfm) and at regeneration temperatures up to 120/sup 0/C (248/sup 0/F). Tests of a 74-cm(29-in.)-diameter, 3.2-c… more
Date: August 1, 1982
Creator: Kutscher, C F & Barlow, R S
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Kinetics of silica polymerization

Description: The polymerization of silicic acid in geothermal brine-like aqueous solutions to produce amorphous silica in colloidal form has been studied experimentally and theoretically. A large amount of high quality experimental data has been generated over the temperature rang 23 to 100{sup 0}C. Wide ranges of dissolved silica concentration, pH, and sodium chloride concentration were covered. The catalytic effects of fluoride and the reaction inhibiting effects of aluminum and boron were studied also. T… more
Date: May 1, 1980
Creator: Weres, O.; Yee, A. & Tsao, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of a solar-desiccant dehumidifier. Phase II second technical progress report

Description: The solar desiccant air conditioner (SODAC) system and its operation are described, including the characteristics of the major components, the performance at design conditions, and the control schemes for optimum operation in various climates. The system uses granular silica gel as a desiccant. It may operate in either a recirculated mode (no air exchange between the outside and the conditioned space) or a ventilated mode (air exchanged between outside and conditioned space). The test data in t… more
Date: October 16, 1981
Creator: Rousseau, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic/kinetic reactions in liquid-dominated geothermal systems. Final report

Description: A mobile geothermal well-site test unit at the Mercer 2 well in South Brawley, California (Imperial Valley), was constructed and tested. The equipment controlled, monitored, and recorded all process conditions of single- and dual-flash power cycles. Single- and two-phase flashed brine effluents were flowed through piping component test sections to provide hydrodynamic/kinetic data for scale formation. The unit operated at flowrates in excess of 200 gpm and is designed to accommodate flowrates u… more
Date: April 1, 1982
Creator: Nesewich, J.P. & Gracey, C.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Methane or methanol via catalytic gasification of biomass

Description: Methane and methanol synthesis gas can be produced by steam gasification of biomass in the presence of appropriate catalysts. A 5 cm diameter reactor has been used to determine the desired catalysts and operating temperature. A process development unit (PDU) has demonstrated steam gasification of biomass with catalysts at rates up to 35 kg per hour. Methane yields of 0.28 nm/sup 3/ per kg of dry wood were produced in the small laboratory reactor. Further methanation of the product gas mixture c… more
Date: March 1, 1980
Creator: Mitchell, D. H.; Mudge, L. K.; Robertus, R. J.; Weber, S. L. & Sealock, L. J. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of silica redistribution on performance of high-level nuclear waste repositories in saturated geologic formations

Description: Evaluation of the thermohydrological conditions near high-level waste packages is needed for the design of the waste canister and for overall repository design and performance assessment. Most available studies in this area have assumed that the hydrologic properties of the host rock do not change in response to the thermal, mechanical or chemical effects caused by waste emplacement. However, the ramifications of this simplifying assumption have not been substantiated. We have studied dissoluti… more
Date: November 1, 1985
Creator: Verma, A. & Pruess, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Processability analysis of candidate waste forms. [For SRP high-level wastes]

Description: A quantitative merit evaluation, or processability analysis, was performed to assess the relative difficulty of remote processing of Savannah River Plant high-level wastes for seven alternative waste form candidates. The reference borosilicate glass process was rated as the simplest, followed by FUETAP concrete, glass marbles in a lead matrix, high-silica glass, crystalline ceramics (SYNROC-D and tailored ceramics), and coated ceramic particles. Cost estimates for the borosilicate glass, high-s… more
Date: January 1, 1982
Creator: Gould, Jr, T H; Dunson, Jr, J B; Eisenberg, A M; Haight, Jr, H G; Mello, V E & Schuyler, III, R L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synthesis and characterization of a covalently bound self-assembled macrocycle monolayer thin film for nonlinear optical materials

Description: Synthesis and characterization of covalently bound self-assembled, 5,10,15,20-Tetra(4-pyridyl)-21H,23H-porphine monolayer superlattices on various oxide surfaces such as fused silica, glass or silicon are described. The mono-molecular thin film structures are characterized by UV-visible ({lambda}{sub max} = 447 nm) and FTIR-ATR spectroscopy. In addition, X-ray photoelectron spectroscopy and secondary ion mass spectroscopy studies are used to confirm the formation of a self-assembled monolayer o… more
Date: January 1, 1992
Creator: Li, DeQuan; Swanson, B. I.; Robinson, J. M. & Hoffbauer, M. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Monitoring and repairing geothermal casing cement: a case history

Description: A manmade geothermal reservoir has been created by drilling a deep hole into relatively impermeable hot rocks, creating a large surface area for heat transfer by hydraulic fracturing, then drilling a second hole to intersect the fracture to complete the closed circulation loop. A second generation system, presently being drilled, will entail creating multiple, parallel, vertical fractures between a pair of inclined boreholes. The original completion of injection Hole EE-1, consisting of a conve… more
Date: January 1, 1980
Creator: Pettitt, R.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Krypton retention on solid adsorbents. [Activated alumina; hydrogen mordenite, silver mordenite, sodium mordenite, cerium mordenite-H, cerium mordenite-Na, potassium mordenite-H, potassium mordenite-Na]

Description: An experimental laboratory program was conducted to develop economical solid adsorbents for the retention of krypton from a dissolver off-gas stream. The study indicates that a solid adsorbent system is feasible and competitive with other developing systems which utilize fluorocarbon absorption nd cryogenic distillation. This technology may have potential applications not only in nuclear fuel reprocessing plants, but also in nuclear reactors and in environmental monitoring. Of the 13 prospectiv… more
Date: January 1, 1982
Creator: Monson, P.R. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Collector sealants and breathing. Final Report, 25 September 1978-31 December 1979

Description: The objectives of this program were: (1) to investigate the pertinent properties of a variety of possible sealants for solar collectors and identify the most promising candidates, and (2) to study the effect of breathing in flat-plate, thermal solar collector units. The study involved two types of sealants, Class PS which includes preformed seals or gaskets and Class SC which includes sealing compounds or caulks. It was the intent of the study to obtain data regarding initial properties of cand… more
Date: February 20, 1980
Creator: Mendelsohn, M A; Luck, R M; Yeoman, F A & Navish, Jr, F W
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Removal of silica from spent geothermal brine

Description: Preliminary survey experiments conducted at the LLL Salton Sea Geothermal Test Site in April and May, 1977 are reported. The addition of caustic to raise the brine pH to approximately 6 precipitated silica and other materials. The addition of flocculating agents, such as ferric hydroxide, aids settling and filtration. Small-scale pilot plant studies are recommended.
Date: December 1, 1977
Creator: Ryon, R.W. & Hill, J.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Clearlake Hot Dry Rock geothermal project: Institutional policies, administrative issues, and technical tasks

Description: The Clearlake Project is a three-party collaboration between the California Energy Commission, City of Clearlake, and Los Alamos National Laboratory. It aims to develop a deep hot, dry geothermal resource under the city. The project is funded by the Commission, and administered by the City. Technical operations are conducted by Laboratory staff and resources seconded from the Hot Dry Rock program. In addition to the normal geothermal exploration problems of predicting geological and geophysical… more
Date: January 1, 1991
Creator: Burns, K.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemistry of silica in Cerro Prieto brines

Description: The precipitation of amorphous silica from synthetic geothermal brines which resemble the flashed brine at Cerro Prieto has been studied. It was found that part of the dissolved silica quickly polymerizes to form suspended colloidal silica. The colloidal silica flocculates and settles slowly at unmodified brine pH values near 7.35. Raising the pH of the brine to about 7.8 by adding base and stirring for a few minutes causes rapid and complete flocculation and settling. These results have been c… more
Date: April 1, 1980
Creator: Weres, O.; Tsao, L. & Iglesias, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low enthalpy convective system in Western Ohio

Description: A distinct positive anomaly in the temperatures of the shallow (Pleistocene) aquifers along the Cincinnati-Findlay Arch in Western Ohio coincides with a low geothermal gradient. A conceptual model of convective currents associated with a tensional fault and/or fracture system along the crest of the Arch is suggested as an explanation of the anomaly. Hydrochemical information indicates that various quantities of warmer ground water, with the composition characteristics of deep bedrock aquifers, … more
Date: January 1, 1980
Creator: Cannon, Melinda S.; Tabet, Charles A. & Eckstein, Yoram
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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