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Graphic values for some organic constitutents of beneficiated coal samples

Description: Graphic techniques exist which can accurately predict values for calorific value, organic sulfur, and possibly other constituents of the organic portion of beneficiated coal sample fractions. These techniques also permit a determination of coal rank to be made without the use of the approximations required in the standard procedure. Fractions of IBC-101 with varying ash contents were produced by froth flotation. The various fractions were analyzed by the coal analysis laboratory and the particu… more
Date: January 1, 1992
Creator: Kohlenberger, L. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Kinetics of coal pyrolysis and devolatilization

Description: Research continued on coal devolatilization. Results are presented for rapid devolatilization experiments performed with the 20 -- 30 micron size cut of the reference coal - PSOC 1451D - a high volatile bituminous, Appalachian Province coal. In agreement with behavior observed in rapid, radiant transient heating experiments -flash lamp - and moderate heating rate - heated grid - experiments for the same coal, the devolatilization process is observed to occur in four distinct phases: intrapartic… more
Date: January 1, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vertical borehole design and completion practices used to remove methane gas from mineable coalbeds

Description: Coalbed gas drainage from the surface in advance of mining has long been the goal of researchers in mine safety. Bureau of Mines efforts to achieve this goal started about 1965 with the initiation of an applied research program designed to test drilling, completion, and production techniques for vertical boreholes. Under this program, over 100 boreholes were completed in 16 different coalbeds. The field methods derived from these tests, together with a basic understanding of the coalbed reservo… more
Date: August 1, 1980
Creator: Lambert, S. W.; Trevits, M. A. & Steidl, P. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Kinetics of coal pyrolysis and devolatilization

Description: Research continued an coal pyrolysis and devolatilization. An experimentally based, conceptual model of the devolatilization of a HV bituminous coal is outlined in this repair. This model contends that the relative dominance of a process type-chemical kinetic, heat transport, mass transport -- varies with the extent of reaction for a given set of heating conditions and coal type and with experimental and with experimental conditions for a given coal types and extent of reaction. The relevant re… more
Date: January 1, 1987
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal combustion: Effect of process conditions on char reactivity

Description: The project will quantify the effect of the following pyrolysis conditions on the macropore structure and on the subsequent reactivity of chars: (a) pyrolysis heating rate; (b) final heat treatment temperature (HTT); (c) duration of heat treatment at HTT (or soak time); (d) pyrolysis atmosphere (N{sub 2} or O{sub 2}/N{sub 2} mixtures); (e) coal particle size (100--1,000 {mu}m in diameter); (f) sulfur-capturing additives (limestone); and (g) coal rank. Pyrolysis experiments will be carried out f… more
Date: January 1, 1992
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coal combustion: Effect of process conditions on char reactivity

Description: The project will quantify the effect of the following pyrolysis conditions on the macropore structure and on the subsequent reactivity of chars: (a) pyrolysis heating rate; (b) final heat treatment temperature (HTT); (c) duration of heat treatment at HTT (or soak time); (d) pyrolysis atmosphere (N{sub 2} or O{sub 2}/N{sub 2} mixtures); (e) coal particle size (100 {endash} 1000 {mu}m in diameter); (f) sulfur-capturing additives (limestone); and (g) coal rank. Pyrolysis experiments will be carrie… more
Date: January 1, 1991
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Structure and chemistry of coals: calorimetric analyses. [Wetting heat]

Description: Heats of immersion (h/sub i/) of coals have been shown to be a valuable means of investigating structure and chemistry of coals. This report outlines some of the factors involved. Lower ranked coals imbibe more liquids (i.e., H/sub 2/O) onto more polar sites (carbonyl, phenolic, etc.) than higher ranked coals. Mineral matter reacts strongly with polar liquids (i.e., H/sub 2/O) giving rise to enhanced h/sub i/. Grinding of coals not only decreases particle size but modifies the coal structure to… more
Date: January 1, 1979
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sulfur and ash reduction potential and selected chemical and physical properties of United States coals. [Contains glossary]

Description: This report presents the washability and comprehensive characterization results of 184 raw coal channel samples, including anthracite, bituminous and lignite coals, collected from the Central Region of the United States. This is the second of a three volume report on the coals of the United States. All the data are presented in six appendices. Statistical techniques and definitions are presented in Appendix A, and a glossary of terms is presented in Appendix B. The complete washability data and… more
Date: February 1, 1991
Creator: Cavallaro, J.A.; Deurbrouck, A.W.; Killmeyer, R.P.; Fuchs, W. (USDOE Pittsburgh Energy Technology Center, PA (USA). Coal Preparation Div.) & Jacobsen, P.S. (Burns and Roe Services Corp., Pittsburgh, PA (USA))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanisms and kinetics of coal hydrogenation. Quarterly progress report, October-December 1979

Description: Colorado School of Mines is conducting coal hydrogenation research with the following objectives and scope of work: (1) Comparison of the rates of coal hydrogenation in continuous flow stirred tank and tube flow reactors using pure hydrogen, catalyzed CO-STEAM, and syngas processing conditions; (2) Investigation of the influence of coal rank on the rate of hydrogenation of coal to preasphaltene, asphaltenes, and oil in batch reactors; (3) Batch evaluation of the effect of operating conditions (… more
Date: February 1, 1980
Creator: Gary, J. H.; Baldwin, R. M. & Bain, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pyrolysis and gasification of coal at high temperatures

Description: Coals of different ranks will be pyrolyzed in a microscope hot-stage reactor using inert and reacting atmosphere. The macropore structure of the produced chars will be characterized using video microscopy and digital image processing techniques to obtain pore size distributions. Comparative studies will quantify the effect of pyrolysis conditions (heating rates, final heat treatment temperatures, particle size and inert or reacting atmosphere) on the pore structure of the devolatilized chars. T… more
Date: January 1, 1989
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pyrolysis and gasification of coal at high temperatures

Description: Coals of different ranks will be pyrolyzed in a microscope hot-stage reactor using inert and reacting atmospheres. The macropore structure of the produced chars will be characterized using video microscopy and digital image processing techniques to obtain pore size distributions. Comparative studies will quantify the effect of pyrolysis conditions (heating rates, final heat treatment temperatures, particle size and inert or reacting atmosphere) on the pore structure of the devolatilized chars. … more
Date: January 1, 1988
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pyrolysis and gasification of coal at high temperatures

Description: Coals of different ranks will be pyrolyzed in a microscope hot-stage reactor using inert and reacting atmospheres. The macropore structure of the produced chars will be characterized using video microscopy and digital image processing techniques to obtain pore size distributions. Comparative studies will quantify the effect of pyrolysis conditions (heating rates, final heat treatment temperatures, particle size and inert or reacting atmosphere) on the pre structure of the devolatilized chars. T… more
Date: January 1, 1989
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Magnetic relaxation--coal swelling, extraction, pore size

Description: The grant activities during this period fall into four categories: (1) Completion of preparatory work, (2) Procedure refinement and actual preparation of whole coal, coal residue, coal extract and swelled coal samples for NMR studies, (3) Related studies of coal photolysis that employ materials from preliminary extractions and that examine the u.v.-visible and mass spectra of the extracts and (4) Continued investigations of the pulsed EPR characteristics of the whole coal samples that were prep… more
Date: January 1, 1991
Creator: Doetschman, D.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fundamental Studies of Retrograde Reactions in Direct Liquefaction

Description: The overall objective of the program was to improve the understanding of retrograde reactions and their dependencies on coal rank and structure, and/or coal modifications and reaction conditions. Because retrograde reactions are competitive with bond breaking reactions, an understanding of both is required to shift the competition in favor of the latter. Related objectives were to clarify the conflicting observations reported in literature on such major topics as the role of oxygen groups in re… more
Date: December 17, 1991
Creator: Serio, M. A.; Solomon, P. R.; Kroo, E.; Charpenay, S. & Bassilakis, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemistry of coal-related microparticles

Description: The objective of this research is to develop and apply novel single microparticle techniques to perform simultaneously thermogravimetric analysis and Raman/fluorescence spectroscopies on microparticles of coal (macerals) and sorbents (CaO) used for coal desulfurization. The combination electrodynamic balance/spectrometer system is being used to chemically characterize macerals from different ranks of coal and to explore the chemistry and chemical reaction rates associated with processes involvi… more
Date: January 1, 1991
Creator: Davis, E.J. & Krieger-Brockett, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of the rank dependence of tar evolution

Description: The objective of this study are to develop an improved understanding of the process of coal tar evolution, its relationship to the structural characteristics of the parent coal, and the dependence of the chemical and physical properties of the tar products on the conditions of devolatilization. Data from this study are expected to allow hypothesis testing and refinements of coal devolatilization models relevant to the pulverized coal combustion process. A range of coal ranks, from a Texas ligni… more
Date: January 1, 1990
Creator: Freihaut, J. D. & Proscia, W. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of reflectance of coal macerals: its automation and significance

Description: A prime objective of the Pennsylvania State University's DOE program is the characterization of 1,300 samples of U.S. coals. Reflectance determination plays a major role in meeting this objective, because it is used as an accurate rank index both to select coals for testing and to investigate property-behavior interrelationships using the Penn State/DOE Coal Data Base. Reflectances of coal macerals are related to their refractive and absorptive indices by the Beer equation; the refractive … more
Date: June 1, 1978
Creator: Davis, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of coals, other kerogens, and their extracts by thermal mass spectrometry

Description: The objective of this study is to elucidate the nature of the medium size molecules derived from coals by a succession of stronger extraction conditions. The Argonne Premium Coals have been extracted with pyridine, binary solvents and with KOH/ethylene glycol at 250{degrees}C. Thermal desorption and pyrolysis mass spectrometry were the major approaches chosen to provide detailed information on structure and heteroatom composition. Soft ionization techniques including desorption chemical ionizat… more
Date: January 1, 1992
Creator: Winans, R. E.; Melnikov, P. E. & McBeth, R. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reaction-induced temperature deviations during coal devolatilization in a heated grid

Description: To gain further insight into the primary devolatilization process, particularly with respect to the tar yields, a new control circuit was designed to permit any heating rate from 800 C/sec to 4 x 10/sup 3/ C/sec to any final temperature in the 300 to 1100/sup 0/C range. With this circuit, the effects of sample characteristics on local heating of the grid were examined to assess the influence of devolatilization on programmed heating rates. The results clearly demonstrate that the devolatilizati… more
Date: January 1, 1981
Creator: Freihaut, J.D.; Zabielski, M.F. & Seery, D.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The mobile phase in coals: Its nature and modes of release: Part 2, Efforts to better define the nature and magnitude of the mobile phase: Final report

Description: Several liquefaction conditions and many extracting solvents were used in attempts to set up conditions such that, as the conditions became more severe, progressively more hexane-solubles, analyzable by GC/MS, would be released. It was hoped to identify a threshold beyond which trapped mobile phase molecules would become evident. A set of 10 hexane-soluble fractions, all obtained under various conditions from the same coal (a sample of Herrin No. 6 seam, Illinois), were subjected to analysis by… more
Date: April 1, 1987
Creator: Given, P.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

Description: The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal conversion utilizing low rank coals and low severity conditions (reaction temperatures generally less than 350{degrees}C) are the primary focus of the liquefaction experiments, as it is expected that the effec… more
Date: 1990-06~
Creator: Baldwin, R. M. & Miller, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reactivity of heat treated coals in steam

Description: Reactivities of seventeen 40 x 100 mesh US coals charred to 1000/sup 0/C have been measured at 910/sup 0/C in 0.1 MPa of a N/sub 2/-H/sub 2/O mixture containing water vapor at a partial pressure of 2.27 kPa. Char reactivity decreases, in general, with increasing rank of the parent coal. The chars show a 250-fold difference in their reactivities. Results suggest that gasification of chars in air, CO/sub 2/ and steam involves essentially the same mechanism and that relative gasification rates are… more
Date: April 1, 1979
Creator: Linares-Solano, A.; Mahajan, O. P. & Walker, Jr., P. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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