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Modeling of Texas Gulf Coast Geopressured Geothermal Aquifers

Description: We would like to report that, at this time, we have coded and tested a model that simulates the behavior of a geopressured geothermal aquifer as it is subjected to production from one or more wells. We have tested this simulator by checking its computed responses against results as reported for systems that span the range of the abilities of the simulator. The general objective of our work was to develop and test a simulator for geopresured geothermal aquifers. The simulator considers the effects of heterogeneous and anisotropic porous media, and the presence of two fluid phases, water and natural gas. The natural gas can exist either in solution or as a separate and distinct flowing phase. The model includes several drive mechanisms which we feel will be significant: these include the water compressibility, the rock matrix compressibility, the changes that occur in pore volume as the aquifer is compacted, the influx of water from adjacent shales either at the edge of the sandstone body or immediately above it or below it, and the expansion of the natural gas either in solution or as a free-phase. We feel that such a model can be used for depletion studies. With the addition of thermal effects it can be used to study the feasibility of reinjecton of “cool” used water. The simulator is the result of combining the momentum transport equation for water and gas with constitutive equations describing the changes of fluid properties with pressure and the changes of formation parameters, such as porosity, permeability and formation thickness with decreasing pore pressure. The resulting equations, shown in the appendix, are solved using finite difference methods to obtain pressure distributions within the aquifer. The energy transport equation can be added to the set of equations and solved to obtain temperature distributions. At ...
Date: December 1, 1976
Creator: Knapp, R.M.; Dorfman, M.H. & Isokrari, O.F.
Partner: UNT Libraries Government Documents Department

Microbial field pilot study

Description: The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year's report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.
Date: March 1, 1992
Creator: Knapp, R.M.; McInerney, M.J.; Menzie, D.E. & Chisholm, J.L.
Partner: UNT Libraries Government Documents Department

Microbial field pilot study

Description: The objective of this project is to perform a microbial enhanced oil recovery field pilot test in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate-reducing bacteria will be stimulated to selectively plug flow paths which have been preferentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. During this quarter an additional tracer study was performed in the field to determine pre-treatment flow paths and the first nutrients were injected. 2 figs.
Date: December 6, 1991
Creator: Knapp, R.M.; McInerney, M.J. & Menzie, D.E.
Partner: UNT Libraries Government Documents Department

Microbial enhancement of oil production from carbonate reservoirs

Description: The goal of this work is to evaluate the potential for Microbial Enhanced Oil Recovery (MEOR) in carbonate reservoirs. Specific objectives include: review of the literature pertinent to MEOR in carbonate reservoirs, a study of the microbial ecology of carbonate reservoirs, isolation of microorganisms and their end-products of metabolism on carbonate pore structure, the recovery of residual oil from carbonates in model core systems, and development of models to examine and predict MEOR processes in carbonate reservoirs. 1 ref., 3 figs., 1 tab.
Date: January 1, 1991
Creator: Tanner, R.S.; Knapp, R.M.; McInerney, M.J. & Udegbunam, E.O.
Partner: UNT Libraries Government Documents Department

Microbial field pilot study

Description: The objective of this project is to perform a microbially enhanced oil recovery field pilot test in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. Indigenous, anaerobic, nitrate-reducing bacteria will be stimulated to selectively plug flow paths which have been preferentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. 1 fig., 2 tabs.
Date: January 1, 1991
Creator: Knapp, R.M.; McInerney, M.J. & Menzie, D.E.
Partner: UNT Libraries Government Documents Department

Microbial field pilot study

Description: The objective of this project is to perform a microbially enhanced oil recovery field pilot test in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate-reducing bacteria will be stimulated to selectively plug flow paths which have been preferentially swept by a prior waterflood. This will force future flood water to invade bypassed regions or the reservoir and increase sweep efficiency. Injection of nutrient stimulates the growth and metabolism of reservoir bacteria, which produces beneficial products to enhance oil recovery. Sometimes, chemical treatments are used to clean or condition injection water. Such a chemical treatment has been initiated by Sullivan and Company at the Southeast Vassar Vertz Sand Unit. The unit injection water was treated with a mixture of water, methanol, isopropyl alcohol, and three proprietary chemicals. To determine if the chemicals would have an impact on the pilot, it was important to determine the effects of the chemical additives on the growth and metabolism of the bacteria from wells in this field. Two types of media were used: a mineral salts medium with molasses and nitrate, and this medium with 25 ppm of the treatment chemicals added. Samples were collected anaerobically from each of two wells, 1A-9 and 7-2. A sample from each well was inoculated and cultured in the broth tubes of molasses-nitrate medium with and without the chemicals. Culturing temperature was 35{degrees}C. Absorbance, pressure and cell number were checked to determine if the chemicals affected the growth and metabolism of bacteria in the brine samples. 12 figs.
Date: January 1, 1991
Creator: Knapp, R.M.; McInerney, M.J. & Menzie, D.E.
Partner: UNT Libraries Government Documents Department

Microbial Field Pilot Study

Description: This report covers progress made during the first year of the Microbial Field Pilot Study project. Information on reservoir ecology and characterization, facility and treatment design, core experiments, bacterial mobility, and mathematical modeling are addressed. To facilitate an understanding of the ecology of the target reservoir analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. A preliminary design of facilities for the operation of the field pilot test was prepared. In addition, procedures for facilities installation and for injection treatments are described. The Southeast Vassar Vertz Sand Unit (SEVVSU), the site of the proposed field pilot study, is described physically, historically, and geologically. The fields current status is presented and the ongoing reservoir simulation is discussed. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. Two possible mechanisms, relative permeability effects and changes in the capillary number, are discussed and related to four Berea core experiments' results. The experiments were conducted at reservoir temperature using SEVVSU oil, brine, and bacteria. The movement and activity of bacteria in porous media were investigated by monitoring the growth of bacteria in sandpack cores under no flow conditions. The rate of bacteria advancement through the cores was determined. A mathematical model of the MEOR process has been developed. The model is a three phase, seven species, one dimensional model. Finite difference methods are used for solution. Advection terms in balance equations are represented with a third- order upwind differencing scheme to reduce numerical dispersion and oscillations. The model is applied to a batch fermentation example. 52 refs., 26 figs., 21 tabs.
Date: November 1, 1990
Creator: Knapp, R.M.; McInerney, M.J.; Menzie, D.E. & Chisholm, J.L.
Partner: UNT Libraries Government Documents Department

Quantitation of microbial products and their effectiveness in enhanced oil recovery. Final report

Description: A three-dimensional, three-phase, multiple-component numerical simulator was developed to investigate transport and growth of microorganisms in porous media and the impacts of microbial activities on oil recovery. The microbial activities modeled in this study included: (1) growth, retention, chemotaxis, and end product inhibition of growth, (2) the formation of metabolic products, and (3) the consumption of nutrients. Major mechanisms for microbial enhanced oil recovery (MEOR) processes were modeled as follows: (1) improvement in sweep efficiency of a displacement process due to in situ plugging of highly-permeable production zones by cell mass or due to improved mobility control achieved by increasing the viscosity of the displacing fluid with a biopolymer, and (2) solubilization and mobilization of residual oil in porous media due to the reduction of the interfacial tension between oleic and aqueous phases by the production of a biosurfactant. The numerical solutions for mathematical models involved two steps. The distributions of pressure and phase saturations were solved from continuity equations and Darcy flow velocities for the aqueous phase were computed. This was followed by the solution of convection-dispersion equations for individual components. Numerical solutions from the proposed model were compared to results obtained from analytical equations, commercial simulators, and laboratory experiments. The comparison indicated that the model accurately quantified microbial transport and metabolism in porous media, and predicted additional crude oil recovery due to microbial processes. 50 refs., 41 figs., 26 tabs.
Date: February 1, 1995
Creator: Zhang, X.; Knapp, R. M. & McInerney, M. J.
Partner: UNT Libraries Government Documents Department

Microbial field pilot study. [Quarterly report], July 1, 1992--September 30, 1992

Description: The objective of this project is to perform a microbial enhanced oil recovery field pilot test in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate-reducing bacteria will be stimulated to selectively plug flow paths which have been preferentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. During this quarter an additional tracer study was performed in the field to determine pre-treatment flow paths and the first nutrients were injected. 2 figs.
Date: December 6, 1991
Creator: Knapp, R. M.; McInerney, M. J. & Menzie, D. E.
Partner: UNT Libraries Government Documents Department

Quantitation of microbial products and their effectiveness in enhanced oil recovery. Quarterly technical progress report, October 16, 1992--January 16, 1993

Description: The goals of this project are to determine the growth kinetics and the relationships that exist between microbial growth, microbial product formation and oil recovery, and to develop mathematical models that predict microbial activity in porous materials. The studies on the influence of microbial growth and product formation on the recovery of residual oil from Berea sandstone cores were continued this quarter. The experiments were carried out at 36{degrees}C using the high pressure core apparatus described previously. Four microbial and nutrient treatments were carried out on a single Berea sandstone core, using the microorganism Clostridium acetobutylicum suspended in a glucose-mineral salts medium. The experimental conditions used are listed in Table 1. Microbial growth in the core was monitored by following pore pressure changes.
Date: December 31, 1992
Creator: McInerney, M. J. & Knapp, R. M.
Partner: UNT Libraries Government Documents Department

Microbial field pilot study

Description: A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m[sup 3]) of tertiary oil have been recovered. Microbial activity has increased CO[sub 2] content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.
Date: May 1, 1993
Creator: Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Coates, J.D. & Chisholm, J.L.
Partner: UNT Libraries Government Documents Department

Microbial field pilot study. Final report

Description: A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m{sup 3}) of tertiary oil have been recovered. Microbial activity has increased CO{sub 2} content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.
Date: May 1, 1993
Creator: Knapp, R. M.; McInerney, M. J.; Menzie, D. E.; Coates, J. D. & Chisholm, J. L.
Partner: UNT Libraries Government Documents Department

Microbial field pilot study

Description: The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year`s report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.
Date: March 1, 1992
Creator: Knapp, R. M.; McInerney, M. J.; Menzie, D. E. & Chisholm, J. L.
Partner: UNT Libraries Government Documents Department

DEVELOPMENT OF MICROORGANISMS WITH IMPROVED TRANSPORT AND BIOSURFACTANT ACTIVITY FOR ENHANCED OIL RECOVERY

Description: Biosurfactants enhance hydrocarbon biodegradation by increasing apparent aqueous solubility or affecting the association of the cell with poorly soluble hydrocarbon. Here, we show that a lipopeptide biosurfactant produced by Bacillus mojavensis strain JF-2 mobilized substantial amounts of residual hydrocarbon from sand-packed columns when a viscosifying agent and a low molecular weight alcohol were present. The amount of residual hydrocarbon mobilized depended on the biosurfactant concentration. One pore volume of cell-free culture fluid with 900 mg/l of the biosurfactant, 10 mM 2,3-butanediol and 1000 mg/l of partially hydrolyzed polyacrylamide polymer mobilized 82% of the residual hydrocarbon. Consistent with the high residual oil recoveries, we found that the bio-surfactant lowered the interfacial tension (IFT) between oil and water by nearly 2 orders of magnitude compared to typical IFT values of 28-29 mN/m. Increasing the salinity increased the IFT with or without 2,3-butanediol present. The lowest interfacial tension observed was 0.1 mN/m. The lipopeptide biosurfactant system may be effective in removing hydrocarbon contamination sources in soils and aquifers and for the recovery of entrapped oil from low production oil reservoirs. Previously, we reported that Proteose peptone was necessary for anaerobic growth and biosurfactant production by B. mojavensis JF-2. The data gathered from crude purification of the growth-enhancing factor in Proteose peptone suggested that it consisted of nucleic acids; however, nucleic acid bases, nucleotides or nucleosides did not replace the requirement for Proteose Peptone. Further studies revealed that salmon sperm DNA, herring sperm DNA, Echerichia coli DNA and synthetic DNA replaced the requirement for Proteose peptone. In addition to DNA, amino acids and nitrate were required for anaerobic growth and vitamins further improved growth. We now have a defined medium that can be used to manipulate growth and biosurfactant production. As an initial step in the search for a better biosurfactant-producing microorganism, 157 bacterial ...
Date: June 26, 2003
Creator: McInerney, M.J.; Knapp, R.M.; D.P. Nagle, Jr.; Duncan, Kathleen; Youssef, N.; Folmsbee, M.J. et al.
Partner: UNT Libraries Government Documents Department

Development of More Effective Biosurfactants for Enhanced Oil Recovery/Advanced Recovery Concepts Awards

Description: The objectives of this were two fold. First, core displacement studies were done to determine whether microbial processes could recover residual oil at elevated pressures. Second, the importance of biosurfactant production for the recovery of residual oil was studies. In these studies, a biosurfactant-producing, microorganisms called Bacillus licheniformis strain JF-2 was used. This bacterium produces a cyclic peptide biosurfactant that significantly reduces the interfacial tension between oil and brine (7). The use of a mutant deficient in surfactant production and a mathematical MEOR simulator were used to determine the major mechanisms of oil recovery by these two strains.
Date: May 28, 2002
Creator: McInerney, M.J.; Marsh, T.L.; Zhang, X.; Knapp, R.M.; Nagle, Jr., D.P.; Sharma, P.K. et al.
Partner: UNT Libraries Government Documents Department

Development of an In Situ Biosurfactant Production Technology for Enhanced Oil Recovery

Description: The long-term economic potential for enhanced oil recovery (EOR) is large with more than 300 billion barrels of oil remaining in domestic reservoirs after conventional technologies reach their economic limit. Actual EOR production in the United States has never been very large, less than 10% of the total U. S. production even though a number of economic incentives have been used to stimulate the development and application of EOR processes. The U.S. DOE Reservoir Data Base contains more than 600 reservoirs with over 12 billion barrels of unrecoverable oil that are potential targets for microbially enhanced oil recovery (MEOR). If MEOR could be successfully applied to reduce the residual oil saturation by 10% in a quarter of these reservoirs, more than 300 million barrels of oil could be added to the U.S. oil reserve. This would stimulate oil production from domestic reservoirs and reduce our nation's dependence on foreign imports. Laboratory studies have shown that detergent-like molecules called biosurfactants, which are produced by microorganisms, are very effective in mobilizing entrapped oil from model test systems. The biosurfactants are effective at very low concentrations. Given the promising laboratory results, it is important to determine the efficacy of using biosurfactants in actual field applications. The goal of this project is to move biosurfactant-mediated oil recovery from laboratory investigations to actual field applications. In order to meet this goal, several important questions must be answered. First, it is critical to know whether biosurfactant-producing microbes are present in oil formations. If they are present, then it will be important to know whether a nutrient regime can be devised to stimulate their growth and activity in the reservoir. If biosurfactant producers are not present, then a suitable strain must be obtained that can be injected into oil reservoirs. We were successful in answering all three ...
Date: September 30, 2007
Creator: McInerney, M. J.; Knapp, R. M.; Duncan, Kathleen; Simpson, D. R.; Youssef, N.; Ravi, N. et al.
Partner: UNT Libraries Government Documents Department