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Treatment of Produced Water Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System

Description: Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. Produced waters typically contain a high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component as well as chemicals added during the oil-production process. It has been estimated that a total of 14 billion barrels of produced water were generated in 2002 from onshore operations (Veil, 2004). Although much of this produced water is disposed via reinjection, environmental and cost considerations can make surface discharge of this water a more practical means of disposal. In addition, reinjection is not always a feasible option because of geographic, economic, or regulatory considerations. In these situations, it may be desirable, and often necessary from a regulatory viewpoint, to treat produced water before discharge. It may also be feasible to treat waters that slightly exceed regulatory limits for re-use in arid or drought-prone areas, rather than losing them to reinjection. A previous project conducted under DOE Contract DE-AC26-99BC15221 demonstrated that surfactant modified zeolite (SMZ) represents a potential treatment technology for produced water containing BTEX. Laboratory and field experiments suggest that: (1) sorption of benzene, toluene, ethylbenzene and xylenes (BTEX) to SMZ follows linear isotherms in which sorption increases with increasing solute hydrophobicity; (2) the presence of high salt concentrations substantially increases the capacity of the SMZ for BTEX; (3) competitive sorption among the BTEX compounds is negligible; and, (4) complete recovery of the SMZ sorption capacity for BTEX can be achieved by air sparging the SMZ. This report summarizes research for a follow on project to optimize the regeneration process for multiple sorption/regeneration cycles, and to develop and incorporate a vapor phase bioreactor (VPB) system for treatment of the off-gas generated during air sparging. To this end, we ...
Date: January 31, 2006
Creator: Katz, Lynn E.; Kinney, Kerry A.; Bowman, Robert S.; Sullivan, Enid J.; Kwon, Soondong; Darby, Elaine B. et al.
Partner: UNT Libraries Government Documents Department

Analysis of reinjectiion strategies for The Geysers

Description: The Geysers has undergone severe pressure decline in recent years, and reinjection of condensate is thought to be one key to sustaining current steam production. Other methods of pressure maintenance include load cycling, or reduction of steam production during off-peak hours. It is likely that a combination of these two will prove to be optimum in providing pressure and fluid maintenance. This paper presents preliminary results of a study of various injection schemes for The Geysers. A number of injection scenarios are investigated, and an optimum scheme (based on specific parameters) is identified for two different quantities of reinjection.
Date: January 1, 1991
Creator: Shook, Mike & Faulder, D.D.
Partner: UNT Libraries Government Documents Department

The Response to Exploitation of Rotorua Geothermal Field

Description: The concern about possible decline in Whakarewarewa spring activity led to the creation of the rotorua Monitoring Program and the rotorua Task Force. Both will shortly issue their final reports (Ministry of Energy 1985a,b). Under the Monitoring Program a considerable database was collected about aquifer, well and spring behavior. From this it has been concluded that exploitation has had the following effects: (1) geothermal aquifer pressures have fallen by up to 0.5 bar; geothermal aquifer pressures beneath Whakarewarewa have fallen by about 0.2 bar; and (3) geothermal flow from Whakarewarewa has been reduced by about half. The effects on the springs could be reduced by reducing withdrawal particularly near Whaka, reinjection (including the use of downhole heat exchangers), or a combination of these.
Date: January 21, 1986
Creator: Grant, Malcolm A.
Partner: UNT Libraries Government Documents Department

Session: Reservoir Technology

Description: This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five papers: ''Reservoir Technology'' by Joel L. Renner; ''LBL Research on the Geysers: Conceptual Models, Simulation and Monitoring Studies'' by Gudmundur S. Bodvarsson; ''Geothermal Geophysical Research in Electrical Methods at UURI'' by Philip E. Wannamaker; ''Optimizing Reinjection Strategy at Palinpinon, Philippines Based on Chloride Data'' by Roland N. Horne; ''TETRAD Reservoir Simulation'' by G. Michael Shook
Date: January 1, 1992
Creator: Renner, Joel L.; Bodvarsson, Gudmundur S.; Wannamaker, Philip E.; Horne, Roland N. & Shook, G. Michael
Partner: UNT Libraries Government Documents Department

A STUDY ON GEOTHERMAL RESERVOIR ENGlNEERING APPROACH COMBINED WITH GEOLOGICAL INFORMATIONS

Description: This paper presents the combined approaches of reservoir geology and engineering to a geothermal field where geological characteristics are highly complex and heterogeneous.Especially,the concrete approaches are discussed for the case of geothermal reservoir performance studies with a developed numerical model, by showing example cases accompanied with reinjection of produced disposal hot water into underground in an object geothermal reservoir. This combined approach will be a great help in solving complicated problems encountered during the development of a geothermal field.
Date: January 22, 1985
Creator: Hirakawa, S.; Yamaguchi, S. & Yoshinobu, F.
Partner: UNT Libraries Government Documents Department

The NABIR Strategic Plan 2001

Description: For more than 50 years, the U.S. created a vast network of more than 113 facilities for research, development, and testing of nuclear materials. As a result of these activities, subsurface contamination has been identified at over 7,000 discrete sites across the U.S. Department of Energy (DOE) complex. With the end of the Cold War threat, the DOE has shifted its emphasis to remediation, decommissioning, and decontamination of the immense volumes of contaminated groundwater, sediments, and structures at its sites. DOE is currently responsible for remediating 1.7 trillion gallons of contaminated groundwater, an amount equal to approximately four times the daily U.S. water consumption, and 40 million cubic meters of contaminated soil, enough to fill approximately 17 professional sports stadiums. It is estimated that more than 60% of DOE facilities have groundwater contaminated with metals or radionuclides. The only contaminant that appears more often than metal and radionuclide contaminants in groundwater is chlorinated hydrocarbons. More than 50% of all soil and sediments at DOE facilities are contaminated with metal and radionuclides, the contaminants found with the highest frequency in soil at all DOE waste sites. Indeed, while virtually all of the contaminants found at industrial sites nationwide can also be found at DOE sites, many of the metals and especially the radionuclides found on DOE sites are unique to those sites. Current technology for treatment of groundwater contaminated with metals and/or radionuclides is ''pump and treat,'' followed by disposal or reinjection of treated water. This process can be costly and inefficient due to the difficulty of completely removing the contaminated groundwater and sorption of contaminants on mineral surfaces. DOE's Office of Environmental Management (EM), which is responsible for the cleanup, has stated that advances in science and technology are critical for DOE to reduce costs and successfully address these long-term ...
Date: October 22, 2001
Partner: UNT Libraries Government Documents Department

TECHNICAL AND OPERATING SUPPORT FOR PILOT DEMONSTRATION OF MORPHYSORB ACID GAS REMOVAL PROCESS

Description: GTI and Krupp Uhde have been jointly developing advanced technology for removing high concentrations of acid gas from high-pressure natural gas for over a decade. This technology, the Morphysorb{reg_sign} process, based on N-formyl and N-acetyl morpholine mixtures, has now been tested in a large-scale facility and this paper presents preliminary results from acceptance testing at that facility. Earlier publications have discussed the bench-scale and pilot plant work that led up to this important milestone. The site was Duke Energy's new Kwoen sour gas upgrader near Chetwynd B.C., Canada. This facility has a nameplate capacity of 300 MMscfd of sour natural gas. The objective of the Morphysorb process at this site was to remove 33 MMscfd of acid gas (H{sub 2}S and CO{sub 2}) for reinjection downhole. This represents about half the acid gas present in the feed to the plant. In so doing, proportionately more of the plant ''sales'' gas, which is sent for final processing at the nearby Pine River plant, can be sent down the line without coming up against the sulfur removal capacity limits of Pine River plant, than could with other solvents that were evaluated. Other benefits include less loss of methane downhole with the rejected acid gas and lower circulation and recycle compression horsepower than with competitive solvents. On the downside, the process is expected to have higher solvent vaporization losses than competitive solvents, but this is a comparatively minor drawback when weighed against the value of the benefits. These benefits (and drawbacks) were developed into quantitative ''acceptance'' criteria, which will determine if the solvent will continue to be used at the site and for award of monetary bonuses to the process developer (GTI).
Date: June 30, 2003
Creator: Palla, Nagaraju & Leppin, Dennis
Partner: UNT Libraries Government Documents Department

TECHNICAL AND OPERATING SUPPORT FOR PILOT DEMONSTRATION OF MORPHYSORB ACID GAS REMOVAL PROCESS

Description: GTI and Krupp Uhde have been jointly developing advanced technology for removing high concentrations of acid gas from high-pressure natural gas for over a decade. This technology, the Morphysorb{reg_sign} process, based on N-formyl and N-acetyl morpholine mixtures, has now been tested in a large-scale facility and this paper presents preliminary results from acceptance testing at that facility. Earlier publications have discussed the bench-scale and pilot plant work that led up to this important milestone. The site was Duke Energy's new Kwoen sour gas upgrader near Chetwynd B.C., Canada. This facility has a nameplate capacity of 300 MMscfd of sour natural gas. The objective of the Morphysorb process at this site was to remove 33 MMscfd of acid gas (H{sub 2}S and CO{sub 2}) for reinjection downhole. This represents about half the acid gas present in the feed to the plant. In so doing, proportionately more of the plant ''sales'' gas, which is sent for final processing at the nearby Pine River plant, can be sent down the line without coming up against the sulfur removal capacity limits of Pine River plant, than could with other solvents that were evaluated. Other benefits include less loss of methane downhole with the rejected acid gas and lower circulation and recycle compression horsepower than with competitive solvents. On the downside, the process is expected to have higher solvent vaporization losses than competitive solvents, but this is a comparatively minor drawback when weighed against the value of the benefits. These benefits (and drawbacks) were developed into quantitative ''acceptance'' criteria, which will determine if the solvent will continue to be used at the site and for award of monetary bonuses to the process developer (GTI).
Date: September 30, 2003
Creator: Palla, Nagaraju & Leppin, Dennis
Partner: UNT Libraries Government Documents Department

SDG and E/ERDA Geothermal Loop Experimental Facility. Brine reinjection pump report

Description: The physical description of the pump and its history of operation and maintenance from May through December, 1976 are presented. A detailed discussion of modifications made to the pump is included. Summaries regarding the compatibility of the pump with the GLEF operation are included. (MHR)
Date: January 1, 1977
Creator: Bishop, H.K; Bricarello, J.R.; Enos, F.L.; Hodgdon, N.C.; Jacobson, W.O.; Li, K.K. et al.
Partner: UNT Libraries Government Documents Department

Analysis of thermally induced permeability enhancement in geothermal injection wells

Description: Reinjection of spent geothermal brine is a common means of disposing of geothermal effluents and maintaining reservoir pressures. Contrary to the predictions of two-fluid models (two-viscosity) of nonisothermal injection, an increase of injectivity, with continued injection, is often observed. Injectivity enhancement and thermally-affected pressure transients are particularly apparent in short-term injection tests at the Los Azufres Geothermal Field, Mexico. During an injection test, it is not uncommon to observe that after an initial pressure increase, the pressure decreases with time. As this typically occurs far below the pressure at which hydraulic fracturing is expected, some other mechanism for increasing the near-bore permeability must explain the observed behavior. This paper focuses on calculating the magnitude of the nearbore permeability changes observed in several nonisothermal injection tests conducted at the Los Azufres Geothermal Field.
Date: February 1, 1987
Creator: Benson, S.M.; Daggett, J.S.; Iglesias, E.; Arellano, V. & Ortiz-Ramirez, J.
Partner: UNT Libraries Government Documents Department

Integrated Geothermal Well Testing: Test Objectives and Facilities

Description: A new and highly integrated geothermal well test program was designed for three geothermal operators in the US (MCR, RGI and Mapco Geothermal). This program required the design, construction and operation of new well test facilities. The main objectives of the test program and facilities are to investigate the critical potential and worst problems associated with the well and produced fluids in a period of approximately 30 days. Field and laboratory investigations are required to determine and quantify the problems of fluid production, utilization and reinjection. The facilities are designed to handle a flow rate from a geothermal well of one million pounds per hour at a wellhead temperature of approximately 268 C (515 F). The facilities will handle an entire spectrum of temperature and rate conditions up to these limits. All pertinent conditions for future fluid exploitations can be duplicated with these facilities, thus providing critical information at the very early stages of field development. The new well test facilities have been used to test high temperature, liquid-dominated geothermal wells in the Imperial Valley of California. The test facilities still have some problems which should be solvable. The accomplishments of this new and highly integrated geothermal well test program are described in this paper.
Date: January 1, 1981
Creator: Nicholson, R. W. & Vetter, O. J.
Partner: UNT Libraries Government Documents Department

Internal Technical Report, Summary of Raft River Supply and Injection System Operational History

Description: Asbestos-cement (Transite) pipe was installed at the Raft River Geothermal Area in the fall of 1975 and has been used extensively since. The pipe is used to transfer water from the well sites to the testing areas, reserve pits, and reinjection wells. The pipeline was designed to transport approximately 300 F water at 150 psi over a period of time for the present testing program and later, for the 5 MW(e) Raft River Pilot Plant. Numerous line failures have occurred since the original lines were installed. Due to the various causes of the line failures and the extensive downtime which has occurred because of them, further examination of Transite pipe is necessary to determine its future use as completion of the 5 MW(e) pilot plant approaches. The Conversion Technology and Engineering Branch has completed a preliminary study of the effects of S&I system transients on Transite pipe (re: OJD-7-79). Recommendations are proposed to conduct further studies and tests; however, no funding is presently available due to limitations in the budget for the 5 MW(e) pilot plant project. The Mechanical Design Branch is continuing design analysis in an effort to gather information to determine maximum warmup rates for the S&I system.
Date: January 1, 1980
Creator: Walrath, L.F.
Partner: UNT Libraries Government Documents Department

Hot Dry Rock Geothermal Reservoir Model Development at Los Alamos

Description: Discrete fracture and continuum models are being developed to simulate Hot Dry Rock (HDR) geothermal reservoirs. The discrete fracture model is a two-dimensional steady state simulator of fluid flow and tracer transport in a fracture network which is generated from assumed statistical properties of the fractures. The model's strength lies in its ability to compute the steady state pressure drop and tracer response in a realistic network of interconnected fractures. The continuum approach models fracture behavior by treating permeability and porosity as functions of temperature and effective stress. With this model it is practical to model transient behavior as well as the coupled processes of fluid flow, heat transfer, and stress effects in a three-dimensional system. The model capabilities being developed will also have applications in conventional geothermal systems undergoing reinjection and in fractured geothermal reservoirs in general.
Date: March 21, 1989
Creator: Robinson, Bruce A. & Birdsell, Stephen A.
Partner: UNT Libraries Government Documents Department

A comparison of hydrothermal reservoirs of the Western United States. Topical Report 3

Description: This report presents a portion of the results from a one-year feasibility study sponsored by the Electric Power Research Institute to assess the feasibility of constructing a 25 to 50 MWe geothermal power plant using low salinity hydrothermal fluids as the energy source. It contains the results of a comparative study of sixteen hydrothermal reservoirs in the US. The reservoirs were selected for comparison on the basis of available data, development potential, and representativeness of known hydrothermal reservoirs in the US. Six reservoir and fluid criteria were considered the most important in determining the development and power conversion potential: depth and lithology, reservoir temperature, tested flow rate per well, fluid chemistry, magnitude of the reserve and reinjection potential. These criteria were evaluated for each of the selected reservoirs.
Date: December 1, 1976
Creator: Meidav, H. Tsvi & Sanyal, Subir
Partner: UNT Libraries Government Documents Department

What Defines a Separate Hydrothermal System

Description: Separate hydrothermal systems can be defined in a variety of ways. Criteria which have been applied include separation of heat source, upflow, economic resource and geophysical anomaly. Alternatively, connections have been defined by the effects of withdrawal of economically useful fluid and subsidence, effects of reinjection, changes in thermal features, or by a hydrological connection of groundwaters. It is proposed here that: ''A separate hydrothermal system is one that is fed by a separate convective upflow of fluid, at a depth above the brittle-ductile transition for the host rocks, while acknowledging that separate hydrothermal systems can be hydrologically interconnected at shallower levels''.
Date: January 1, 1995
Creator: Lawless, J.V.; Bogie, I. & Bignall, G.
Partner: UNT Libraries Government Documents Department

Modeling Studies of Cold Water Injection into Fluid-Depleted, Vapor-Dominated Geothermal Reservoirs

Description: Reinjection experiments in the strongly fluid-depleted reservoir of Larderello have revealed the possibility of increasing production rates and overall heat extraction by injection into high permeability, low pressure zones of the reservoir (Giovannoni et al., 1981; Cappetti et al., 1983; Bertrami et al., 1985). A large fraction (over 80%) of the injected water was recovered as steam in the most favorable area and, despite the short distance between injection and producing wells (the minimum distance being about 150 m), no significant temperature change has been observed in the latter, after 3 years of injection at a rate ranging from 10 to 50 kg/s (Bertrami et al., 1985). The physical processes involved in cold water injection into a ''superheated'' fractured reservoir are not yet fully understood, and this insufficient knowledge of the fundamental mechanisms limits the possibility of forecasting future reservoir behavior and optimizing the heat extraction process. Numerical simulation can be a very effective tool in the study of the complex phenomena involved, allowing a rapid examination of different situations and conditions, a systematic investigation of the effects of various parameters on reservoir performance, and some insight into long term behavior. We have performed simulation experiments on simple one-dimensional, porous and fractured reservoir models in order to study the migration of injected water, thermodynamic conditions in the boiling zone, heat extraction, and vapor generation. A two-dimensional radial porous medium model, with some characteristics typical of the high productivity zones of Larderello, has, also been applied for studying the- evolution. of the shape and the thermodynamic conditions of the injection plume in the presence of gravity, reservoir heterogeneities and anisotropy.
Date: January 21, 1986
Creator: Calore, C.; Pruess, K. & Celati, R.
Partner: UNT Libraries Government Documents Department

Geothermal reservoir engineering research in New Zealand: A simplistic model and the Wairakei geothermal reservoir

Description: Although nowadays much of the New Zealand geothermal reservoir research effort is still being concentrated on the older fields of Wairakei and Broadlands there has been a definite advance over recent years in our approach to the studies. On the practical side, long term reinjection trials are now in progress at Broadlands, and drilling, for field evaluation, is well underway at Ngawha, a field characterized by a steam discharge coupled with a hydrostatic pressure gradient. On the theoretical side, well pressure transient analysis and reservoir behavior modeling are probably the primary interests. For the former both multi-element computer modeling programs and two-phase pressure diffusion analysis (Grant, 1978, Grant and Sorey, 1979) are being used by M.A.Grant, E.Bradford and F.Sutton (AMD*) and M.L.Sorey (PEL). Geometry and boundary influences are dominant and estimated steam flows are higher than are consistent with the Corey (1954) expressions for relative permeability. Both of these effects are probably due to the fracture permeability of the reservoirs. A.McNabb (AMD) is currently taking this into account by determining the response to discharge in a fracture-block medium. He is working with 100 meter blocks, consistent with data from lumped parameter models and from well records, with a block permeability of 10{sup -15} m{sup 2}. Reservoir behavior modeling is probably the research area of greatest current interest with most research groups here involved to some extent. The models range over a wide spectrum, from extreme simplification to sophisticated detail. At the simpler extreme is the model of J.Elder (AU). This consists of two resistors and a condenser in electrical analog form but is coupled with models of the well system and the above surface plant to enable overall system effects and interactions to be assessed.
Date: January 1, 1978
Creator: Donaldson, Ian G.
Partner: UNT Libraries Government Documents Department

Single Borehole Geothermal Energy Extraction System for Electrical Power Generation

Description: The Extraction System utilizes heat transferred from the geothermal fluids into a closed combined Heat Pipe/Organic Rankine Cycle. The system overcomes problems of reinjection, two phase fluid movement and environmental pollution by bringing a clean secondary fluid to the surface. Reservoir fracturing and primary fluid movement will also be covered.
Date: January 21, 1986
Creator: Lockett, George E.
Partner: UNT Libraries Government Documents Department

Microseismic monitoring of the Sweet Lake, Louisiana, MagmaGulf-Technadril/D.O.E./Amoco Fee No. 1 Geopressured/Geothermal Energy Test Well Program: Final Report, 20 May 1980-31 May 1984

Description: The overall objective of the project was to study the seismic effects of fluid withdrawal from deep reservoirs and its subsequent reinjection closer to the surface. This effort included the design and installation of a hardware system and development of a study approach to monitor dynamic deformation in the Gulf Coast environment. Over the long term, insight gained into the ground deformation process (specifically ground subsidence) may potentially allow the integration of observations of individual phenomena into predictive tools for future use in ground subsidence studies. The value of a seismic monitoring network as a predictive tool can only be evaluated by an integrated program to study ground and instrument performance with time. Integrating extended real time monitoring of potential seismic precursors to significant displacements may represent the first integrated study of subsidence undertaken in the Gulf Coast region.
Date: May 31, 1984
Partner: UNT Libraries Government Documents Department

Optimizing Reinjection Strategy at Palinpinon, Philippines Based on Chloride Data

Description: One of the guidelines established for the safe and efficient management of the Palinpinon Geothermal Field is to adopt a production and well utilization strategy such that the rapid rate and magnitude of reinjection fluid returns leading to premature thermal breakthrough would be minimized. To help achieve this goal, sodium fluorescein and radioactive tracer tests have been conducted to determine the rate and extent of communication between the reinjection and producing sectors of the field. The first objective of this paper is to show how the results of these tests, together with information on field geometry and operating conditions were used in algorithms developed in Operations Research to allocate production and reinjection rates among the different Palinpinon wells. Due to operational and economic constraints, such tracer tests were very limited in number and scope. This prevents obtaining information on the explicit interaction between each reinjection well and the producing wells. Hence, the chloride value of the producing well, was tested to determine if use of this parameter would enable identifying fast reinjection paths among different production/reinjection well pairs. The second aim, therefore, of this paper is to show the different methods of using the chloride data of the producing wells and the injection flow rates of the reinjection wells to provide a ranking of the pair of wells and, thereby, optimize the reinjection strategy of the field.
Date: March 24, 1992
Creator: Urbino, Ma. Elena G. & Horne, Roland N.
Partner: UNT Libraries Government Documents Department

Pressure-interference testing of the Sumikawa geothermal field

Description: Pressure interference tests have been used to determine the permeability structure of the Sumikawa reservoir. Interference tests between wells S-4 and KY-1 have indicated the presence of a very high permeability (140 md) north-south channel in the altered andesite layer. Pressure buildup data from well SN-7D have provided indications of a high transmissivity (kh {approx} 18 darcy-meters) reservoir located in the granodiorite layer, lack of pressure response in nearby shutin Sumikawa wells implies that the reservoir penetrated by SN-7D is isolated from the shallower reservoir in the altered andesites. The ''altered andesite'' and the ''granodiorite'' formations constitute the principal geothermal aquifers at Sumikawa. Pressure interference tests (wells KY-1 and SB-2, and wells KY-2 and SB-3) have also confirmed the presence of moderately high transmissivity ({approx} 2 darcy-meters) dacitic layers in the ''marine-volcanic complex'' formation. Because of its low vertical permeability, the ''marine volcanic complex'' formation constitutes an attractive target for the reinjection of waste geothermal fluids.
Date: January 1, 1991
Creator: Garg, S.K.; Pritchett, J.W.; Ariki, K. & Kawano, Y.
Partner: UNT Libraries Government Documents Department

Study of Water Reinjection on the Kamojang Geothermal Reservoir Performance, Indonesia

Description: A reservoir simulation model study was developed to investigate effects of water reinjection into the performance of Kamojang geothermal field. Several cases including the existing injection wells and rates, the effect of injection rates, location and depth of proposed injection wells were run to study the temperature, pressure and fluid distribution in the reservoir and its effect into the reservoir and production performance for 30 years of prediction. The results show that the reservoir pressure and temperature drops are very small (4 bar and 5 C, respectively) at the end of the prediction time; therefore, the production target of 140 MW for 30 years can still be accomplished.
Date: January 1, 1995
Creator: Darwis, R.S.; Tampubolon, T.; Simatupang, R. & Asdassah, D.
Partner: UNT Libraries Government Documents Department

Simulation of geothermal reservoirs including changes in porosity and permeability due to silica-water reactions

Description: Changes in porosity and permeability due to water-rock reactions may affect a geothermal reservoir in two important ways. One is the possibility of clogging of the pore space in the vicinity of a reinjection well. The second concerns the long term evolution of a geothermal system, for example, the development of a self-sealing cap rock. Two major types of reactions that may affect the porosity and permeability in the reservoir are dissolution-precipitation reactions and alteration reactions. Silica precipitation is the major self-sealing process in hot-water geothermal reservoirs. The purpose of this work is to develop a mathematical model which can simulate the changes in porosity and permeability resulting from water-rock reactions in a geothermal reservoir. The model being developed describes the flow of hot water in an axially symmetric porous medium. The model is a vertical cross-section in r-z coordinates. For simplicity, only a single dissolved chemical species is being modeled. The fluid is single-phase water and only dissolution and precipitation of quartz are considered.
Date: January 1, 1978
Creator: Li, Todd M.C.; Mercer, J.W.; Faust, C.R. & Greenfield, R.J.
Partner: UNT Libraries Government Documents Department