89 Matching Results

Search Results

Modeling Studies of Geothermal Systems with a Free Water Surface

Description: Numerical simulators developed for geothermal reservoir engineering applications generally only consider systems which are saturated with liquid water and/or steam. However, most geothermal fields are in hydraulic communicatino with shallow ground water aquifers having free surface (water level), so that production or injection operations will cause movement of the surface, and of the air in the pore spaces above the water level. In some geothermal fields the water level is located hundreds of meters below the surface (e.g. Olkaria, Kenya; Bjornsson, 1978), so that an extensive so that an extensive unsaturated zone is present. In other the caprock may be very leaky or nonexistent [e.g., Klamath Falls, oregon (Sammel, 1976)]; Cerro Prieto, Mexico; (Grant et al., 1984) in which case ther eis good hydraulic communication between the geothermal reservoir and the shallow unconfined aquifers. Thus, there is a need to explore the effect of shallow free-surface aquifers on reservoir behavior during production or injection operations. In a free-surface aquifer the water table moves depending upon the rate of recharge or discharge. This results in a high overall storativity; typically two orders of magnitude higher than that of compressed liquid systems, but one or two orders of magnitude lower than that for liquid-steam reservoirs. As a consequence, various data analysis methods developed for compressed liquid aquifers (such as conventional well test analysis methods) are not applicable to aquifer with a free surface.
Date: December 15, 1983
Creator: Bodvarsson, Gudmundur S. & Pruess, K.
Partner: UNT Libraries Government Documents Department

Mobility of {sup 129}I in buried waste

Description: To quantify the potential for {sup 129}I to migrate from buried waste at the Savannah River Plant (SRP) burial ground, a four year study was made. Spent berl saddles containing 68.7 mCi of {sup 129}I from separations process air filters were buried in a 10 ft. {times} 10 ft. {times} 12 ft. deep lysimeter exposed to normal weather conditions at the burial ground. During the four year study leaching and migration released 48.5 nCi of {sup 129}I from the 68.7 mCi buried in the lysimeter. This represents an average 1.77 {times} 10{sup {minus}7} fraction/year released. The release rate was relatively constant during the four years, varying mainly with seasonal rainfall. Calculations based on these results indicate a release of <3 {mu}Ci/year of {sup 129}I from SRP buried waste to the groundwater. Qualitatively this release and subsequent migration has recently been confirmed by measurement of 0.25 pCi {sup 129}I /1 in water from a well 600{prime} southwest of the burial ground.
Date: June 15, 1983
Creator: Hawkins, J. R.
Partner: UNT Libraries Government Documents Department

A review of research programs related to the behavior of plutonium in the environment

Description: Plutonium-fueled radioisotopic heat sources find application in a spectrum of space, terrestrial, and underseas applications to generate electrical power by thermoelectric or dynamic-cycle conversion. Such systems under postulated accident conditions could release radioactivity into the environment resulting in risks to the general population. The released radioactivity could be dispersed into various environmental media, such as air, soil, and water and interact with people through various exposure pathways leading to inhalation, ingestion, and external radiological doses and associated health effects. The authors developed short-term exposure (RISK II) and long-term exposure (RISK III) models for use in safety risk assessments of space missions utilizing plutonium-fueled electric power systems. To effectively use these models in risk assessments, representative input values must be selected for a spectrum of environmental transfer parameters that characterize the behavior of plutonium in the environment. The selection of appropriate transfer parameters to be used in a given analysis will depend on the accident scenarios to be modeled and the terrestrial and aquatic environments to be encountered. The authors reviewed the availability of plutonium in the environment. This report summarizes the research programs presently being conducted at six Department of Energy Laboratories and makes recommendations on areas where further research is needed to fill gaps in the data necessary for risk assessments
Date: June 15, 1983
Creator: Bartram, Bart W. & Wilkinson, Martha J.
Partner: UNT Libraries Government Documents Department

Temperatures and interval geothermal-gradient determinations from wells in National Petroleum Reserve in Alaska

Description: Temperature and related records from 28 wells in the National Petroleum Reserve in Alaska (NPRA) although somewhat constrained from accuracy by data gathering methods, extrapolate to undisturbed formation temperatures at specific depths below permafrost, and lead to calculated geothermal graidents between these depths. Tabulation of the results show that extrapolated undisturbed temperatures range from a minimum of 98/sup 0/F (37/sup 0/C) at 4000 feet (1220 m) to a maximum of 420/sup 0/F (216/sup 0/C) at 20,260 feet (6177 m) and that geothermal gradients range from 0.34/sup 0/F/100' (6/sup 0/C/km) between 4470 feet to 7975 feet (Lisburne No. 1) and 3.15/sup 0/F/100' (57/sup 0/C/km) between 6830 feet to 7940 feet (Drew Point No. 1). Essential information needed for extrapolations consists of: time-sequential bottom-hole temperatures during wire-line logging of intermediate and deep intervals of the borehole; the times that circulating drilling fluids had disturbed the formations; and the subsequent times that non-circulating drilling fluids had been in contact with the formation. In several wells presumed near direct measures of rock temperatures recorded from formation fluids recovered by drill stem tests (DST) across thin (approx. 10-20 foot) intervals are made available. We believe that the results approach actual values close enough to serve as approximations of the thermal regimes in appropriate future investigations. Continuous temperature logs obtained at the start and end of final logging operations, conductivity measurements, and relatively long-term measurements of the recovery from disturbance at shallow depths in many of the wells will permit refinements of our values and provide determination of temperatures at other depths. 4 references, 6 figures, 3 tables.
Date: December 15, 1983
Creator: Blanchard, D.C. & Tailleur, I.L.
Partner: UNT Libraries Government Documents Department

Geothermal Energy Technology: a current-awareness bulletin

Description: This bulletin announces on a semimonthly basis the current worldwide information available on the technology required for economic recovery of geothermal energy and its use either directly or for production of electric power. The subject content encompasses: resource status and assessment, geology and hydrology of geothermal systems, geothermal exploration, legal and institutional aspects, economic and final aspects, environmental aspects and waste disposal, by-products, geothermal power plants, geothermal engineering, direct energy utilization, and geothermal data and theory.
Date: January 15, 1983
Creator: Smith, L.B. (ed.)
Partner: UNT Libraries Government Documents Department

Selected data for low-temperature (less than 90{sup 0}C) geothermal systems in the United States: reference data for US Geological Survey Circular 892

Description: Supporting data are presented for the 1982 low-temperature geothermal resource assessment of the United States. Data are presented for 2072 geothermal sites which are representative of 1168 low-temperature geothermal systems identified in 26 States. The low-temperature geothermal systems consist of 978 isolated hydrothermal-convection systems, 148 delineated-area hydrothermal-convection systems, and 42 delineated-area conduction-dominated systems. The basic data and estimates of reservoir conditions are presented for each geothermal system, and energy estimates are given for the accessible resource base, resource, and beneficial heat for each isolated system.
Date: December 15, 1983
Creator: Reed, M.J.; Mariner, R.H.; Brook, C.A. & Sorey, M.L.
Partner: UNT Libraries Government Documents Department

Effects of voltage control in utility interactive dispersed storage and generation systems

Description: When a small generator is connected to the distribution system, the voltage at the point of interconnection is determined largely by the system and not the generator. This report examines the effect on the generator, on the load voltage and on the distribution system of a number of different voltage control strategies in the generator. Synchronous generators with three kinds of exciter control are considered, as well as induction generators and dc/ac inverters, with and without capacitor compensation. The effect of varying input power during operation (which may be experienced by generators based on renewable resources) is explored, as well as the effect of connecting and disconnecting the generator at ten percent of its rated power.
Date: March 15, 1983
Creator: Kirkham, H. & Das, R.
Partner: UNT Libraries Government Documents Department

Environmental, health, and safety assessment of photovoltaics

Description: Potential enviornmental, health, and safety (E,H and S) concerns associated with all phases of the photovoltaic (PV) energy system life cycle are identified and assessed. E,H and S concerns affecting the achievement of National PV Program goals or the viability of specific PV technologies are emphasized. The report is limited to near-term manufacturing process alternatives for crystalline silicon PV materials, addresses flat-plate and concentrator collector designs, and reviews system deployment in grid-connected, roof-mounted, residential and ground-mounted central-station applications. The PV life-cycle phases examined include silicon refinement and manufacture of PV collectors, system deployment, and decommissioning. The primary E,H and S concerns that arise during collector fabrication are associated with occupational exposure to materials of undetermined toxicity or to materials that are known to be hazardous, but for which process control technology may be inadequate. Stricter exposure standards are anticipated for some materials and may indicate a need for further control technology development. Minimizing electric shock hazards is a significant concern during system construction, operation and maintenance, and decommissioning.
Date: October 15, 1983
Creator: Rose, E.C.
Partner: UNT Libraries Government Documents Department

Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems

Description: A Photovoltaic Metallization Research Forum, under the sponsorship of the Jet Propulsion Laboratory&#x27;s Flat-Plate Solar Array Project and the US Department of Energy, was held March 16-18, 1983 at Pine Mountain, Georgia. The Forum consisted of five sessions, covering (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques and (5) future metallization challenges. Twenty-three papers were presented.
Date: November 15, 1983
Partner: UNT Libraries Government Documents Department

Charged-particle beam: a safety mandate

Description: The Advanced Test Accelerator (ATA) is a recent development in the field of charged particle beam research at Lawrence Livermore National Laboratory. With this experimental apparatus, researchers will characterize intense pulses of electron beams propagated through air. Inherent with the ATA concept was the potential for exposure to hazards, such as high radiation levels and hostile breathing atmospheres. The need for a comprehensive safety program was mandated; a formal system safety program was implemented during the project's conceptual phase. A project staff position was created for a safety analyst who would act as a liaison between the project staff and the safety department. Additionally, the safety analyst would be responsible for compiling various hazards analyses reports, which formed the basis of th project's Safety Analysis Report. Recommendations for safety features from the hazards analysis reports were incorporated as necessary at appropriate phases in project development rather than adding features afterwards. The safety program established for the ATA project faciliated in controlling losses and in achieving a low-level of acceptable risk.
Date: July 15, 1983
Creator: Young, K.C.
Partner: UNT Libraries Government Documents Department

Inertial effects in laser-driven ablation

Description: The gasdynamic partial differential equations (PDE's) governing the motion of an ablatively accelerated target (rocket) contain an inertial force term that arises from acceleration of the reference frame in which the PDE's are written. We give a simple, intuitive description of this effect, and estimate its magnitude and parametric dependences by means of approximate analytical formulas inferred from our computer hydrocode calculations. Often this inertial term is negligible, but for problems in the areas of laser fusion and laser equation of state studies we find that it can substantially reduce the attainable hydrodynamic efficiency of acceleration and implosion.
Date: July 15, 1983
Creator: Harrach, R.J.; Szeoke, A. & Howard, W.M.
Partner: UNT Libraries Government Documents Department

Review of the Tandem Mirror Experiment-Upgrade (TMX-U) machine-parameter-instrumentation system

Description: The Tandem Mirror Experiment-Upgrade (TMX-U) machine consists of seven major machine subsystems: magnet system, neutral beam system, microwave heating (ECRH), ion heating (ICRH), gas fueling, stream guns, and vacuum system. Satisfactory performance of these subsystems is necessary to achieve the experimental objectives planned for TMX-U operations. Since the performance quality of the subsystem is important and can greatly affect plasma parameters, a 233-channel instrumentation system has been installed. Data from the instrumentation system are acquired and stored with the plasma diagnostic information. Thus, the details of the machine performance are available during post-shot analysis. This paper describes all the machine-parameter-instrumentation hardware, presents some typical data, and outlines how the data are used.
Date: November 15, 1983
Creator: Kane, R.J.; Coffield, F.E.; Coutts, G.W. & Hornady, R.S.
Partner: UNT Libraries Government Documents Department

Sodium Reactor Experiment decommissioning. Final report

Description: The Sodium Reactor Experiment (SRE) located at the Rockwell International Field Laboratories northwest of Los Angeles was developed to demonstrate a sodium-cooled, graphite-moderated reactor for civilian use. The reactor reached full power in May 1958 and provided 37 GWh to the Southern California Edison Company grid before it was shut down in 1967. Decommissioning of the SRE began in 1974 with the objective of removing all significant radioactivity from the site and releasing the facility for unrestricted use. Planning documentation was prepared to describe in detail the equipment and techniques development and the decommissioning work scope. A plasma-arc manipulator was developed for remotely dissecting the highly radioactive reactor vessels. Other important developments included techniques for using explosives to cut reactor vessel internal piping, clamps, and brackets; decontaminating porous concrete surfaces; and disposing of massive equipment and structures. The documentation defined the decommissioning in an SRE dismantling plan, in activity requirements for elements of the decommissioning work scope, and in detailed procedures for each major task.
Date: August 15, 1983
Creator: Carroll, J.W.; Conners, C.C.; Harris, J.M.; Marzec, J.M. & Ureda, B.F.
Partner: UNT Libraries Government Documents Department

20-TeV colliding-beam facilities

Description: In March, a workshop was held at Cornell University on the accelerator. The conclusion of this workshop was that a 20 TeV on 20 TeV proton-proton collider is technically feasable, that construction could begin after 2.5 to 4 years of research and development, and the cost would be 1.3 to 2 billion dollars. To put this machine into perspective one must consider the existing facilities listed in table I. There are about 23 high energy physics laboratories in the world that are being operated or constructed. Most of these labs have an effective energy of less than 100 GeV and study principally the known quarks and leptons. The only accelerator operating at an effective energy greater than 100 GeV is the CERN proton-antiproton system. As has been presented at this conference in other papers their success has been great in a very short time, the discovery of the vector bosons W and Z. The only machine approved that will have an effective energy greater than 1000 GeV is the Russian accelerator UNK. The effective energy of a 20 TeV on 20 TeV proton-proton collider would be about 15 TeV.
Date: September 15, 1983
Creator: Huson, F.R.
Partner: UNT Libraries Government Documents Department

Attempt to compare two arc orbit correction schemes analytically

Description: Consider a transport line that consists of periodic cells. Let the beam position monitors and the orbit correctors be located with the same period as the cells and let the BPM's and the corrector distributions interlace each other. The arrangement does not always provide a stable orbit correction. The criterion for stability has been derived by Joe Murray and is reproduced. We calculate the rms orbit, the effect of BPM errors and the rms corrector strength in such correction schemes, yielding analytic formulae for these quantities. We then apply these formulae to the SLC arcs.
Date: December 15, 1983
Creator: Chao, A. & Weng, W.
Partner: UNT Libraries Government Documents Department

Deploymerization of coal by direct solvent attack. Semi-annual report, April 1, 1983-August 31, 1983

Description: The depolymerization of Illinois No. 6 coal by a series of solvents having different basecities (pK/sub a/) and nucleophilicities (Swain-Scott nu values) showed no dependence on either the basicity of nucleophilicity of the solvents. As expected, the conversion decreases as the temperature of the reaction is reduced, but the lower the reaction temperature, the higher the percentage of amine incorporation becomes in the products. 5 tables.
Date: September 15, 1983
Creator: Larsen, J.W. & Mohammadi, M.
Partner: UNT Libraries Government Documents Department