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Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures

Description: This project attempts to demonstrate the effectivensss of exploiting thin-layered, low energy deposits at the distal margin of a propagating turbinite complex through u se of hydraulically fractgured horizontal of high-angle wells. TGhe combinaton of a horizontal or high-angle weoo and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore.
Date: February 5, 1998
Creator: Laue, Mike L.
Partner: UNT Libraries Government Documents Department

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures

Description: This project attempts to demonstrate the effectiveness of exploiting thin-layered, low energy deposits at the distal end of a protruding turbidite complex through use of hydraulically fractured horizontal of high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than conventional vertical wells while maintaining vertical communication between thin interbedded layers and the well bore.
Date: May 29, 1998
Creator: Laue, Mike L.
Partner: UNT Libraries Government Documents Department

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures

Description: This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a propagating turbidite complex through the use of hydraulically-fractured horizontal or high-angle wells. The combination of a horizontal or high-angled well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thininterbedded layers and the well bore.
Date: May 8, 1997
Creator: Laue, Mike L.
Partner: UNT Libraries Government Documents Department

STUDY OF SOLVENT AND CATALYST INTERACTIONS IN DIRECT COAL LIQUEFACTION

Description: Using a reactor in which the coal is physically separated from the solid catalyst by a porous wall permeable to the hydrogen donor solvent, it was shown that direct contact between the catalyst and the coal is not required for catalyzed coal liquefaction. This occurs however only when there is a hydrogen atmosphere, as liquefaction with catalyst participation does not occur in a nitrogen atmosphere. Liquefaction by hydrogen transfer from the donor solvent itself does occur. This suggests that there is transfer of hydrogen from the catalyst to the coal via the solvent. The character of the solvent makes a significant difference, the better solvents being good hydrogen donors. These results indicate that the role of the catalyst may be to regenerate the spent hydrogen donor solvent during the liquefaction process. The peak temperature for volatiles evolution has been shown to be a reproducible measure of the coal rank. This was shown by an excellent correlation (R2 = 0.998) between peak volatiles temperatures (by TGA) and vitrinite reflectance. Using TG/MS, the volatiles contents of coals of a wide range of ranks was determined. The low rank coals emit largely phenols and some other oxygen compounds and olefins. The higher rank coals emit largely aromatic hydrocarbons and some olefins.
Date: January 1, 2000
Creator: Klein, Michael T.
Partner: UNT Libraries Government Documents Department

Vapor pressures and heats of vaporization of primary coal tars. Quarterly technical progress report, April 1, 1996--June 30, 1996

Description: As the world continues to deplete its petroleum reserves, then heavy crude oil, coal liquids, and other heavy fossil fuels may be required to meet the world energy needs. Heavy fossil fuels contain molecules that are large and more aromatic and that contain more heteroatoms than those found in liquid crude oil. There is also significant current interest in general area of coal pyrolysis, particularly with respect to comprehensive models of this complicated phenomenon. This interest derives from central role of pyrolysis in all thermally driven coal conversion processes - gasification, combustion, liquefaction, mild gasification, or thermal beneficiation. There remain several key data needs in these application areas. Among them is a need for a more reliable correlation for prediction of the vapor pressures of heavy, primary coal tars. Such information is important in design of all coal conversion processes, in which the volatility of tarry products is of major concern. This paper presents work on the vapor pressures of coal tars using the continuous knudsen effusion technique.
Date: December 31, 1997
Creator: Suuberg, E.M.; Oja, V. & Lilly, W.D.
Partner: UNT Libraries Government Documents Department

Coal precursors for carbon molecular seives. Quarterly progress report, July 1, 1995--September 30, 1995

Description: Shortly after our Quarterly Report for the period April 1, 1995 - June 30, 1995 was submitted, we completed the last two thermogravimetric-mass spectrographic (TG/MS) analyses of our samples. The results of these analyses will be included in the Final Report with the TG/MS data accumulated for the other coal samples. We then turned our attention to activating each of the coals using air activation. The results of the activation study are reported below.
Date: September 29, 1995
Creator: Kopp, O.C.
Partner: UNT Libraries Government Documents Department

The chemical constitution of Pocahontas No. 3 coal

Description: A new method for the definition of the larger aromatic structural elements in high-rank coals has been developed. The procedure involves the oxidative decom-position of the coal with oxygen in basic solution and the subsequent decarboxylation of the aromatic arboxylic acids to yield a mixture of aromatic compounds that can readily be analyzed by conventional methods. This approach has been tested with pure compounds and applied to Pocahontas No. 3 coal.
Date: December 31, 1995
Creator: Stock, L.M. & Obeng, M.
Partner: UNT Libraries Government Documents Department

Probing coal architecture by magnetic resonance microscopy.

Description: Time-resolved MRM investigations of a well-characterized suite of cross-linked polymers have yielded information on the nature of the solvent transport dynamics and mechanical relaxation of the networks. Network response parameters were then used to assess the macroscopic properties and cross-link densities of polymers with the degree of curing. This new approach is presently being developed to elucidate the complex macromolecular nature of coals and the variation with coal rank.
Date: February 24, 1999
Creator: Botto, R. E.; Clifford, D. J. & Gregory, D. M.
Partner: UNT Libraries Government Documents Department

Coal char fragmentation during pulverized coal combustion

Description: A series of investigations of coal and char fragmentation during pulverized coal combustion is reported for a suite of coals ranging in rank from lignite to low-volatile (lv) bituminous coal under combustion conditions similar to those found in commercial-scale boilers. Experimental measurements are described that utilize identical particle sizing characteristics to determine initial and final size distributions. Mechanistic interpretation of the data suggest that coal fragmentation is an insignificant event and that char fragmentation is controlled by char structure. Chars forming cenospheres fragment more extensively than solid chars. Among the chars that fragment, large particles produce more fine material than small particles. In all cases, coal and char fragmentation are seen to be sufficiently minor as to be relatively insignificant factors influencing fly ash size distribution, particle loading, and char burnout.
Date: July 1, 1995
Creator: Baxter, L.L.
Partner: UNT Libraries Government Documents Department

MAINTENANCE OF THE COAL SAMPLE BANK AND DATABASE

Description: This project provides coal samples and accompanying analytical data for research by DOE contractors and others. All 56 samples have been purged with argon before storage, and the 33 samples in the DECS series are heat-sealed in foil laminate bags and stored under refrigeration. Eleven DECS samples have been collected under the current contract. Basic characterization, standardized liquefaction analyses and organic geochemical analyses have been completed. Distribution of samples and data is continuing, with processing of samples being performed as needed. Nineteen samples, 90 data printouts, and individual data items from 416 samples were distributed during the quarter. Trends and relationships observed in liquefaction and organic geochemical analyses performed under the contract are summarized in this report. Liquefaction results using tetralin were similar to those using 1-methylnaphthalene under the same run conditions. Properties of individual coals, such as maceral composition and corresponding organic chemical components, were important in explaining liquefaction behavior. NMR and py/gc/ms results illustrated trends based on coal rank, and revealed outliers which might be of special interest, for example low-phenolic coals which limit retrogressive reactions and permit greater liquefaction conversion.
Date: August 1, 1998
Creator: Scaroni, Alan W. & Glick, David C.
Partner: UNT Libraries Government Documents Department

Combined thermogravimetric and mass spectroscopic analysis (TG/MS). Quarterly report, April 1, 1995--June 30, 1995

Description: Progress is reported on the analysis of coals using thermogravimetric (TG) and mass spectrographic (MS) analysis and adding information to the database. Samples were analyzed using oxidative pyrolysis. Various types (coal rank) of coal were utilized.
Date: September 1, 1995
Creator: Kopp, O. C.
Partner: UNT Libraries Government Documents Department

STUDY OF SOLVENT AND CATALYST INTERACTIONS IN DIRECT COAL LIQUEFACTION

Description: To provide a better understanding of the roles of a solid catalyst and the solvent in Direct Coal Liquefaction, a small reactor was equipped with a porous-walled basket which was permeable to the solvent but was not permeable to the coal or solid catalyst. With this equipment and a high volatile bituminous coal it was found that direct contact between the catalyst in the basket and the coal outside the basket is not required for catalyzed coal liquefaction. The character of the solvent in this system makes a significant difference in the conversion of the coal, the better solvents being strong donor solvents. Because of the extensive use of thermogravimetric analysis in this laboratory, it was noted that the peak temperature for volatiles evolution from coal was a reliable measure of coal rank. Because of this observation, a variety of coals of a range of ranks was investigated. It was shown in this work that measuring the peak temperature for volatiles evolution was a quite precise indicator of rank and correlated closely with the rank value obtained by measuring vitrinite reflectance, a more difficult measurement to make. This prompted the desire to know the composition of the volatile material evolved as a function of coal rank. This was then measured by coupling a TGA to a mass spectrometer using laser activation and photoionization detection TG-PI-MS. The predominant species in volatiles of low rank coal turned out to be phenols with some alkenes. As the rank increases, the relative amounts of alkene and aromatic hydrocarbons increases and the oxygenated species decrease. It was shown that these volatiles were actually pyrolytic products and not volatilization products of the coal. Solvent extraction experiments coupled with Thermogravimetric-photoionization-mass spectrometry (TG-PI-MS) indicated that the low boiling and more extractable material are essentially similar in chemical types ...
Date: October 4, 2000
Creator: Klein, Michael T.; Calkins, William H. & Tomic, Jasna
Partner: UNT Libraries Government Documents Department

Vapor pressures and heats of vaporization of primary coal tars. Quarterly technical progress report, July 1 - September 31, 1996

Description: The vapor pressure correlations that exist at present for coal tars are very crude and they are not considered reliable to even an order of magnitude. This project seeks to address this important gap in the near term by direct measurement of vapor pressures of coal tar fractions, by application of well-established techniques and modifications thereof. The principal objectives of the program are to: (1) obtain data on the vapor pressures and heats of vaporization of tars from a range of ranks of coal; (2) develop correlations based on a minimum set of conveniently measurable characteristics of the tars; and (3) develop equipment that would allow performing such measurements in a reliable, straightforward fashion. During this quarter we have extended the work on measurements of vapor pressures of coal tars, using the continuous Knudsen effusion technique. These results need further analysis and therefore in this report we describe only the general idea behind the technique, and also show some typical results.
Date: December 31, 1996
Creator: Suuberg, E.M.; Oja, V. & Lilly, W.D.
Partner: UNT Libraries Government Documents Department

Swelling behavior of O-alkylated APCS coals as examined by the EPR spin probe method

Description: Known O-alkylation procedures have been used to derivatize the carboxyl and hydroxyl groups in the APCS coals Lewiston-Stockton, Wyodak-Anderson, Beulah-Zap, Illinois {number_sign}6, Upper Freeport, and Pittsburgh {number_sign}8. In general the resulting decrease in hydrogen bonding reduced the cyclical variation in nitroxide spin probe retention observed for nonalkylated coals when small amounts (<1%) of pyridine are present in the toluene swelling solvent. An increase in spin probe retention by the O-alkylated coals relative to the underivatized coals indicates a more open arrangement in the coal due to a decrease in attractive forces, confirming that microporosity increases with increasing rank.
Date: December 31, 1995
Creator: Ding, Ruisong; Tucker, D. & Kispert, L.D.
Partner: UNT Libraries Government Documents Department

Evaluation of fine-particle size catalysts using standard test procedures

Description: The goal of this project is to evaluate and compare the activities/selectivities of fine-particle size catalysts being developed in the DOE/PETC Advanced Research (AR) Liquefaction Program by using standard coal liquefaction activity test procedures. Since bituminous and subbituminous coals have significantly different properties, it is feasible that catalysts may perform differently with these coal types. Because all previous testing has been done with the DECS-17 Blind Canyon bituminous coal, it is important to develop the capability of evaluating catalysts using a subbituminous coal. Initial efforts towards developing a subbituminous coal test are aimed at comparing the reactivities of the Wyodak subbituminous coal and the Blind Canyon bituminous coal. Therefore, the same factorial experimental design was used with the Wyodak coal as was used previously with the Blind Canyon coal. In addition, PNL`s 6-line ferrihydrite catalyst precursor was used in the development of the Wyodak coal test procedure because this catalyst is the best powder catalyst found to date in Sandia`s tests with Blind Canyon coal. Results show that Blind Canyon coal yields higher DHP amounts in the reaction products and higher tetrahydrofuran conversions at the higher severity conditions. Wyodak coal gives higher heptane conversions and higher gas yields for all conditions tested.
Date: July 1, 1996
Creator: Stohl, F.V.; Diegert, K.V. & Goodnow, D.C.
Partner: UNT Libraries Government Documents Department

Molecular accessibility in oxidized and dried coals. Quarterly report, 1996

Description: The objective of this research project is to determine the molecular and structural changes that occur in swelled coal as a result of oxidation and moisture loss both in the presence and absence of light using our newly developed EPR spin probe method. The proposed study will make it possible to deduce the molecular accessibility distribution in swelled, oxidized APCS coal for each rank as a function of (1) size (up to 6 nm) and shape, (2) the relative acidic/basic reactive site distributions, and (3) the role of hydrogen bonding as a function of swelling solvents. The advantage of the EPR method is that it permits molecules of selected shape, size and chemical reactivity to be used as probes of molecular accessible regions of swelled coal. From such data an optimum catalyst can be designed to convert oxidized coal into a more convenient form and methods can be devised to lessen the detrimental weathering processes. It appears that the observed binary swelling data for the APCS coals studied to date can be explained in terms of four different processes: one, disruption of weak hydrogen bonds which protect or isolate the interconnected micropore system; two, disruption of weak hydrogen bonds which protect individual micropores; three, the competition of pyridine for the active sites capable of establishing hydrogen bonds or the `poisoning` of active sites; four, disruption of stronger hydrogen bonds within the macromolecular structure which cause an opening of the structure. The contributions of each of these factors to the spin probe retention with increasing concentrations of pyridine vary up to 5% pyridine. At concentrations above 5% pyridine, the first factor becomes less significant, and variations in the others require greater changes in pyridine concentration.
Date: June 1, 1996
Creator: Kispert, L.D.
Partner: UNT Libraries Government Documents Department

The application of soft X-ray microscopy to the in-situ analysis of sporopollenin/sporinite in a rank variable suite of organic rich sediments

Description: Soft X-ray imaging and carbon near edge absorption fine structure spectroscopy (C-NEXAFS) has been used for the in-situ analysis of sporinite in a rank variable suite of organic rich sediments extending from recent up to high volatile A bituminous coal. The acquisition of chemically based images (contrast based on the 1s - 1{pi}* transition of unsaturated carbon), revealed a homogeneous chemical structure in the spore exine. C-NEXAFS microanalysis indicates chemical structural evolution in sporopollenin/sporinite with increases in maturation. The most significant change in the C-NEXAFS spectrum is an increase in unsaturated carbon, presumably aromatic, with rank. The rate of aromatization in sporinite exceeds that of the surrounding vitrinite. Increases in the concentration of unsaturated carbon are compensated by losses of aliphatic and hydroxylated aliphatic carbon components. Carboxyl groups are present in low and variable concentrations. Absorption due to carboxyl persists in the most mature specimen in this series, a high volatile A rank coal. The reactions which drive sporopollenin chemical structural evolution during diagenesis presumably involve dehydration, Diels-Alder cyclo-addition, and dehydrogenation reactions which ultimately lead to a progressively aromatized bio/geopolymer.
Date: July 1, 1997
Creator: Cody, G.D.; Botto, R.E.; Ade, H. & Wirick, S.
Partner: UNT Libraries Government Documents Department

Cross-linking a soluble lignin by a coal demineralization treatment

Description: The standard coal demineralization procedure of Bishop and Ward, a modification of earlier work of Radmacher and Mohrhauer. is a strong acid treatment (consecutive exposure of the ground coal to 5N HCl, 48% HF, and 12N HCl, for 45 minute periods at 60 C) that effectively reduces the mineral matter concentration of the coal. The Bishop and Ward paper compared the determination of mineral matter in coals by direct and indirect methods and assessed the applicability of the mineral matter determination to British Coals. The work was oriented toward mineral matter determination and did not address, in detail, the organic matrix of the coal. On the basis of pre- and post-extraction carbon and hydrogen determinations, the authors concluded that the acid treatment caused no significant attack on the coal substance. The present study was undertaken to test whether the exposure of a complex, water insoluble organic matrix containing benzylic alcohol functionality would suffer retrogressive polymerization when exposed to the Bishop and Ward demineralization conditions. This paper reports solubility and structural changes in lignin, a model for the organic matrix of low rank coals, that demonstrate the facility of this reaction channel.
Date: May 1, 1998
Creator: Hagaman, E.W.
Partner: UNT Libraries Government Documents Department

Studies of low rank coal stabilities. Final report

Description: The National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Center, tested feed coal and product samples from Wyoming and Montana for thermal stability in the adiabatic oven and sealed flask apparatus. The results indicated that the products had higher thermal stabilities in comparison with the feed coals. However, both the products samples and feed coals exhibited high spontaneous combustion potentials. A report on these studies was submitted in December 1995. Experiments were also completed in the adiabatic oven to determine the rate of decrease in the heating rate of a reactive sample on exposure to pulses of moist air, and moist nitrogen. The results indicated that with each succeeding pulse, longer time were required to reach selected elevated temperatures. The results also indicated some level of synergy between water and oxygen in the heat generation reaction. The data and results were transmitted to Dr. Dennis Finseth upon completion of the experiments.
Date: March 1, 1998
Partner: UNT Libraries Government Documents Department

Fundamental study of low-NOx combustion fly ash utilization. Semiannual report, May 1, 1998--October 31, 1998

Description: The objective of the current work was to investigate the oxidation reactivity of fly ash carbons, using thermogravimetric analysis techniques. Good measures of the oxidation reactivity of fly ash carbon were the critical temperature (T{sub cr}) and the late burnout temperature (T{sub late}). The lower the critical temperature of the fly ash carbon, the more reactive the sample. By contrast, the higher T{sub late}, the less reactive the fly ash carbon. The difference between T{sub cr} and T{sub late} provided information about the reactivity distribution and was mainly dependent on fly ash carbon content (Loss-On-Ignition (LOI)). Fly ash carbons having different origins, some from lower rank coals and some from higher rank coals had slightly different reactivities. Class C fly ash carbons from low rank coals were more reactive than the typical class F fly ash carbons from higher rank coals. The reactivity parameters did not, however, provide any additional ability to predict the suitability of a given ash for use in concrete.
Date: October 20, 1999
Creator: Hurt, R.H. & Suuberg, E.M.
Partner: UNT Libraries Government Documents Department

Energy and environmental research emphasizing low-rank coal: Task 7.2, Resource data evaluation. Topical report, July 1994--May 1995

Description: The Resource Data Evaluation subtask of the US Department of Energy (DOE) base program represents an Energy & Environmental Research Center (EERC) initiative to promote the integration of geographic information system (GIS) technologies with other ongoing and planned EERC research in the areas of resource utilization, remediation, land use planning, and regulatory and policy assessment. Significant demand for GIS-based information already exists for energy resource evaluation, interpretation of remote sensing data, environmental assessment at the state and local levels, and use in strategic planning. The objective of this task was to determine the appropriate platform and approach upon which to develop GIS applications for optimizing resource evaluation and integrating this information with related areas of interest. Activities associated with Task 7.2, Resource Data Evaluation, were conducted primarily during the first half of the project year. These activities included tasks associated with the development and implementation of GIS databases and construction of digitized files for research pertaining to energy studies. As previously noted, database design was undertaken for two EERC projects: 1) coal occurrence in Bowman and adjacent counties in the Fort Union Coal Region of southwestern North Dakota and 2) energy resource utilization concerns for selected sites in Alaska.
Date: June 1, 1995
Creator: Hartman, J.H.
Partner: UNT Libraries Government Documents Department

Coal plasticity at high heating rates and temperatures. Final technical progress report

Description: Plastic coals are important feedstocks in coke manufacture, coal liquefaction, gasification, and combustion. During these processes, the thermoplastic behavior of these coals is also important since it may contribute to desirable or undesirable characteristics. For example, during liquefaction, the plastic behavior is desired since it leads to liquid-liquid reactions which are faster than solid-liquid reactions. During gasification, the elastic behavior is undesired since it leads to caking and agglomeration of coal particles which result in bed bogging in fixed or fluidized bed gasifiers. The plastic behavior of different coals was studied using a fast-response plastometer. A modified plastometer was used to measure the torque required to turn at constant angular speed a cone-shaped disk embedded in a thin layer of coal. The coal particles were packed between two metal plates which are heated electrically. Heating rates, final temperatures, pressures, and durations of experiment ranged from 200--800 K/s, 700--1300 K, vacuum-50 atm helium, and 0--40 s, respectively. The apparent viscosity of the molten coal was calculated from the measured torque using the governing equation of the cone-and-plate viscometer. Using a concentrated suspension model, the molten coal`s apparent viscosity was related to the quantity of the liquid metaplast present during pyrolysis. Seven coals from Argonne National Laboratory Premium Coal Sample Bank were studied. Five bituminous coals, from high-volatile to low-volatile bituminous, were found to have very good plastic behavior. Coal type strongly affects the magnitude and duration of plasticity. Hvb coals were most plastic. Mvb and lvb coals, though the maximum plasticity and plastic period were less. Low rank coals such as subbituminous and lignite did not exhibit any plasticity in the present studies. Coal plasticity is moderately well correlated with simple indices of coal type such as the elemental C,O, and H contents.
Date: May 1, 1995
Creator: Gerjarusak, S.; Peters, W.A. & Howard, J.B.
Partner: UNT Libraries Government Documents Department

Probing coal reactivity by time-resolved small angle x-ray scattering.

Description: The objective of this study is to observe changes in coal structure in situ with small angle X-ray scattering (SAXS) during solvent swelling and during pyrolysis. We have built a SAXS instrument at the Basic Energy Sciences Synchrotrons Research Center at the Advanced Photon Source that allows us to obtain scattering patterns in the millisecond time domain. The eight Argonne Premium Coal samples were used in this study. The information that can be derived from these experiments, such as changes in fractal dimensionality and in size and type of porosity, was found to be very rank-dependent. In the swelling experiments, it was noted that for certain coals, structural changes occurred in just a few minutes.
Date: January 22, 1999
Creator: Winans, R. E.
Partner: UNT Libraries Government Documents Department

An investigation of the role of water on retrograde/condensation reactions and enhanced liquefaction yields. Final report

Description: While great strides have been made in developing the technology of coal liquefaction processes in recent years, many unsolved problems still remain before a viable and economical process can be achieved. The technological problems that still exist can be solved through a more fundamental understanding of the chemistry associated with each stage of the coal liquefaction process, starting with any pretreatment steps that may be carried out on the coal itself. Western Research Institute, under the a contract from the US Department of Energy, has conducted a study of different methods of coal drying as pretreatment steps before liquefaction. The results of that study are the subject of this report. Coals that were dried or partially dried thermally and with microwaves had lower liquefaction conversions than coals containing equilibrium moisture contents. However, chemically dried coals had conversions equal to or greater than the premoisturized coals. The conversion behavior is consistent with changes in the physical structure and cross linking reactions because of drying. Thermal and microwave drying appear to cause a collapse in the pore structure, thus preventing donor solvents such as tetralin from contacting reactive sites inside the coals. Chemical dehydration does not appear to collapse the pore structure. From the study of the kinetics of the chemical dehydration of coals, it was possible to quantify the amount of water on the surface, the amount readily accessible in pores, and the amount more strongly bonded in the internal structure of the coals. The results indicate that high-rank coals have proportionally less surface and easily accessible water than the lower rank coals.
Date: February 1, 1995
Creator: Miknis, F.P.; Netzel, D.A.; Wallace, J.C. Jr.; Butcher, C.H.; Mitzel, J.M. & Turner, T.F.
Partner: UNT Libraries Government Documents Department