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Advanced drilling systems study.

Description: This report documents the results of a study of advanced drilling concepts conducted jointly for the Natural Gas Technology Branch and the Geothermal Division of the U.S. Department of Energy. A number of alternative rock cutting concepts and drilling systems are examined. The systems cover the range from current technology, through ongoing efforts in drilling research, to highly speculative concepts. Cutting mechanisms that induce stress mechanically, hydraulically, and thermally are included. All functions necessary to drill and case a well are considered. Capital and operating costs are estimated and performance requirements, based on comparisons of the costs for alternative systems to conventional drilling technology, are developed. A number of problems common to several alternatives and to current technology are identified and discussed.
Date: May 1, 1996
Creator: Pierce, Kenneth G.; Livesay, Billy Joe & Finger, John Travis (Livesay Consultants, Encintas, CA)
Partner: UNT Libraries Government Documents Department

Polymer grouts for plugging lost circulation in geothermal wells.

Description: We have concluded a laboratory study to evaluate the survival potential of polymeric materials used for lost circulation plugs in geothermal wells. We learned early in the study that these materials were susceptible to hydrolysis. Through a systematic program in which many potential chemical combinations were evaluated, polymers were developed which tolerated hydrolysis for eight weeks at 500 F. The polymers also met material, handling, cost, and emplacement criteria. This screening process identified the most promising materials. A benefit of this work is that the components of the polymers developed can be mixed at the surface and pumped downhole through a single hose. Further strength testing is required to determine precisely the maximum temperature at which extrusion through fractures or voids causes failure of the lost circulation plug.
Date: December 1, 2004
Creator: Galbreath, D. (Green Mountain International, Waynesvile, NC); Mansure, Arthur James & Bauer, Stephen J.
Partner: UNT Libraries Government Documents Department

Geoengineering: Governance and Technology Policy

Description: This report is intended as a primer on the policy issues, science, and governance of geoengineering technologies. The report will first set the policy parameters under which geoengineering technologies may be considered. It will then describe selected technologies in detail and discuss their status. The third section provides a discussion of possible approaches to governmental involvement in, and oversight of, geoengineering, including a summary of domestic and international instruments and institutions that may affect geoengineering projects.
Date: January 10, 2011
Creator: Bracmort, Kelsi; Lattanzio, Richard K. & Barbour, Emily C.
Partner: UNT Libraries Government Documents Department

Geoengineering: Governance and Technology Policy

Description: This report is intended as a primer on the policy issues, science, and governance of geoengineering technologies. The report will first set the policy parameters under which geoengineering technologies may be considered. It will then describe selected technologies in detail and discuss their status. The third section provides a discussion of possible approaches to governmental involvement in, and oversight of, geoengineering, including a summary of domestic and international instruments and institutions that may affect geoengineering projects.
Date: August 16, 2010
Creator: Bracmort, Kelsi; Lattanzio, Richard K. & Barbour, Emily C.
Partner: UNT Libraries Government Documents Department

Geoengineering: Governance and Technology Policy

Description: This report is intended as a primer on the policy issues, science, and governance of geoengineering technologies. The report will first set the policy parameters under which geoengineering technologies may be considered. It will then describe selected technologies in detail and discuss their status. The third section provides a discussion of possible approaches to governmental involvement in, and oversight of, geoengineering, including a summary of domestic and international instruments and institutions that may affect geoengineering projects.
Date: November 26, 2013
Creator: Bracmort, Kelsi & Lattanzio, Richard K.
Partner: UNT Libraries Government Documents Department

Solar energy task force report technical training guidelines

Description: Guidelines are offered for programs oriented to commercial applications in solar energy, specifically water and space heating. These technologies are examined because they are, in some cases, economicaly feasible. Sample curricula and programs, technical jobs and skills, and equipment are suggested to assist those institutions contemplating the development of technical training. (MHR)
Date: October 1, 1979
Creator: O'Connor, K
Partner: UNT Libraries Government Documents Department

Optimization of injection scheduling in geothermal fields

Description: This study discusses the application of algorithms developed in Operations Research to the optimization of brine reinjection in geothermal fields. The injection optimization problem is broken into two sub-problems: (1) choosing a configuration of injectors from an existing set of wells, and (2) allocating a total specified injection rate among chosen injectors. The allocation problem is solved first. The reservoir is idealized as a network of channels or arcs directly connecting each pair of wells in the field. Each arc in the network is considered to have some potential for thermal breakthrough. This potential is quantified by an arc-specific break-through index, b/sub ij/, based on user-specified parameters from tracer tests, field geometry, and operating considerations. The sum of b/sub ij/-values for all arcs is defined as the fieldwide breakthrough index, B. Injection is optimized by choosing injection wells and rates so as to minimize B subject to constraints on the number of injectors and the total amount of fluid to be produced and reinjected. The study presents four computer programs which employ linear or quadratic programming to solve the allocation problem. In addition, a program is presented which solves the injector configuration problem by a combination of enumeration and quadratic programming. The use of the various programs is demonstrated with reference both to hypothetical data and an actual data set from the Wairakei Geothermal Field in New Zealand.
Date: May 1, 1987
Creator: Lovekin, J.
Partner: UNT Libraries Government Documents Department

Technology assessment of geothermal pumping equipment. final report, July 1978

Description: Twenty-eight separate interviews were conducted with DOE personnel, DOE contractors doing geothermal research, persons associated with geothermal installations, companies engaged in the drilling and completion of geothermal well, and pump manufactures. The reports of these interviews are presented and summarized and conclusions are drawn.
Date: September 1, 1978
Creator: Nichols, K.E. & Malgieri, A.J.
Partner: UNT Libraries Government Documents Department

Safety and emergency preparedness considerations for geotechnical field operations

Description: The GEO Energy Technology Department at Sandia National Laboratories is involved in several remote-site drilling and/or experimental operations each year. In 1987, the Geothermal Research Division of the Department developed a general set of Safe Operating Procedures (SOPs) that could be applied to a variety of projects. This general set is supplemented by site-specific SOPs as needed. Effective field operations require: integration of safety and emergency preparedness planning with overall project planning, training of field personnel and inventorying of local emergency support resources, and, developing a clear line of responsibility and authority to enforce the safety requirements. Copies of SOPs used in recent operations are included as examples of working documents for the reader.
Date: April 1, 1989
Creator: Wemple, R.P.
Partner: UNT Libraries Government Documents Department

Feasibility demonstration of the Sperry down-well pumping system. Final report

Description: Advantages of down-well pumping (vs. free-flowing) of geothermal hot-water wells are presented, and criteria for such a system are discussed. The main body of the report is presented under the following section headings: the Sperry down-well pumping system; field test program; field operations; test results; and, conclusions and recommendations. The appendix includes a summary of boiler heat transfer and pressure drop calculations. (JGB)
Date: May 1, 1977
Partner: UNT Libraries Government Documents Department

Analysis of internal wellbore flow

Description: Most two-phase geothermal wells are located in fractured rocks and intersect a few major feedzones. It is well known that internal wellbore flow between feedzones often occurs during warmup or pressure recovery periods. The internal flow can occur even when the reservoir is initially in pressure equilibrium because of the different phase composition that develops within the wellbore. Internal flow can cause large apparent pressure drawdowns and significantly affect pressure and temperature surveys as well as pressure buildup tests. This paper presents an analytic method for using static pressure surveys to calculate internal flowrates between two zones when the reservoir characteristics are known. Conversely, the transmissivity of the feedzone with the lowest transmissivity can be calculated from measurements of internal flowrates and wellbore pressures. 3 refs., 6 figs.
Date: January 1, 1988
Creator: Ripperda, M. & Bodvarsson, G.S.
Partner: UNT Libraries Government Documents Department

Numerical studies of cold water injection into vapor-dominated geothermal systems

Description: Recent reservoir pressure and steam flow rate declines at The Geysers geothermal field in California have attracted interest in studies of increased cold water injection into this system. In this paper, numerical studies of such injection into a fractured vapor-dominated reservoir are conducted using a two-dimensional radial, double-porosity model. The results obtained indicate that cold water injection into superheated (low-pressure) zones will greatly enhance the productivities of steam wells. Injection into two-phase zones with significant liquid reserves in the matrix blocks does not appear to aid in steam recovery until most of the original liquid reserves are depleted. Sensitivity studies are conducted over the range of fracture and matrix permeabilities applicable to the Geysers. The sensitivity of the grid size is also conducted, and shows very large grid effects. A fine vertical space discretization near the bottom of the reservoir is necessary to accurately predict the boiling of the injected water. 28 refs., 15 figs., 3 tabs.
Date: January 1, 1991
Creator: Lai, C.H & Bodvarsson, G.S.
Partner: UNT Libraries Government Documents Department

Alternate materials of construction for geothermal applications. Progress report No. 15, October 1977--March 1978

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. Test results indicate that polymer concrete (PC) containing mixtures of styrene--acrylonitrile--acrylamide or methacrylamide produces composites with the best high temperature and chemical resistance obtained to date. The results show that the use of a 12 wt % concentration of a 55 wt % styrene--35 wt % acrylonitrile--5 wt % acrylamide--5 wt % trimethylolpropane trimethacrylate monomer mixture in conjunction with 88 wt % of a 70 wt % silica sand--30 wt % Portland cement aggregate produces a composite with a compressive strength at 20/sup 0/C (68/sup 0/F) in the range 25,000 to 30,000 psi. The PC is thermally stable to approximately 240/sup 0/C (464/sup 0/F). Results are also available from field exposures of up to 24 months in four geothermal environments. Good durability is indicated. Work at four of these sites is continuing, and plans to initiate tests at other sites are being implemented.
Date: March 1, 1978
Creator: Steinberg, M. & Kukacka, L.E.
Partner: UNT Libraries Government Documents Department

Evaluation of high temperature lubricants for downhole motors in geothermal applications

Description: A Bearing-Seal Package is being developed for use with downhole motors and turbines for drilling geothermal wells. The lubricant will be sealed in the bearing section which will allow the bearings to operate directly in the lubricant. The development of the Bearing-Seal Package involves the improvement of high temperature seals and lubricants. Candidate high temperature lubricants were tested in the High Temperature Lubricant Tester under elevated temperatures and pressures. A list of candidate high temperature lubricants, a description of the lubricant test program, and the lubricant test results are presented.
Date: January 1, 1979
Creator: DeLafosse, P.H.; Tibbitts, G.A. & Green, S.J.
Partner: UNT Libraries Government Documents Department

Shape memory alloy seals for geothermal applications

Description: A shape memory radial seal was fabricated with a ''U'' cross section. Upon heating the seal recovered its original ''V'' shape and produced a high pressure seal. The sealing pressure which can be developed is approximately 41 MPa (60,000 psi), well in excess of the pressure which can be produced in conventional elastomeric seals. The low modulus martensite can conform readily to the sealing surface, and upon recovery produce a seal capable of high pressure fluid or gas confinement. The corrosion resistance of nickel-titanium in a broad range of aggressive fluids has been well established and, as such, there is little doubt that, had time permitted, a geothermal pump of flange fluid tried would have been successful.
Date: September 15, 1985
Partner: UNT Libraries Government Documents Department

Geothermal down-well pumping system. Final report

Description: A novel method of pumping geothermal hot brines is described. A discussion of the reasons for pumping and a description of the system is reported. The results of the turbopump laboratory tests are documented. The design, construction, and test of a higher flow-rate pump impeller and first-stage diffuser; detailed design improvements in the TPU and continued endurance testing of it; and preliminary planning tasks for the subsequent down-well testing program are covered. (MHR)
Date: August 16, 1976
Partner: UNT Libraries Government Documents Department

Investigation of component failures in downhole geothermal pumping systems. Final report

Description: This study investigated component failures in electric, downhole submersible pumps which prevented the attainment of one year continuous downhole running times in geothermal wells at temperatures up to 375/sup 0/F. The feasibility of a pressurized motor to prevent brine intrusion was investigated, as well as improved pothead and packoff designs, and brine scale buildup on impeller sleeve bearings and thrust washers. (ACR)
Date: March 15, 1985
Creator: Werner, D.K.
Partner: UNT Libraries Government Documents Department

Survey of geothermal completion fluids

Description: A survey of oil field fluids companies indicates that there are no geothermal completion fluids on the market. It is recommended that development of a completion fluid and appropriate support testing be funded.
Date: January 1, 1980
Creator: Childers, M.R.
Partner: UNT Libraries Government Documents Department

Lost circulation in geothermal wells: research and development status

Description: The most common severe problems encountered in drilling and completing geothermal wells are lost circulation (loss of fluid returns to the surface), stuck pipe, and inadequate cementing. Lost circulation is the single most costly and troublesome well development problem; it may also cause or aggravate stuck pipe and cementing problems. Sandia National Laboratories is conducting an aggressive research and development program aimed at understanding and solving lost circulation problems. The program is aimed at finding and characterizing loss zones, modeling the dynamics of zone plugging, testing materials and techniques in the laboratory, and developing holistic solutions for combating lost circulation. Significant work has been completed in instrumentation, materials testing, and numerical modeling. Work devising an ''expert'' system for fluid loss control has begun. 12 refs., 4 figs.
Date: August 1, 1985
Creator: Caskey, B.C. & Satrape, J.V.
Partner: UNT Libraries Government Documents Department

Equipment develoment report: downhole fluid injector

Description: The development, design, fabrication, and operation of a tool used for injecting a discrete quantity of fluid (e.g. a dye) at a desired location within a hot geothermal borehole are described. Assembly and operating instructions are included.
Date: February 1, 1978
Creator: Archuleta, J. R.; Fink, C. F. & Kurtenbach, J.
Partner: UNT Libraries Government Documents Department