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Title: Coal dissolution studies: particle size distribution in coal-derived liquids as a function of degree of coal conversion

Abstract

Exploratory studies were conducted to assess the effect of the degree of coal conversion (i.e., a decrease in the amount of pyridine insolubles) in reacted coal - athracene oil mixtures. Particle size distribution data on the reacted mixtures show that the percentage of particulates < 10 ..mu.. in diameter increases gradually with conversion up to a conversion of about 85%. At higher conversions, the percentage of particulates < 10 ..mu.. in diameter increases dramatically in a near-step, function-like manner. The presence of small particulates are known to be a major cause of the low-filtration rates of coal liquefaction streams. Filtration experiments on the mixtures confirm that a relationship exists between filtration rates and conversion. Thus, the results of this work bear directly on the optimal design of two-stage liquefaction processes and could lead to improved design of processes such as SRC-I.

Authors:
; ;
Publication Date:
Research Org.:
Oak Ridge National Lab., TN (USA)
OSTI Identifier:
6277886
Report Number(s):
ORNL/TM-6681
DOE Contract Number:
W-7405-ENG-26
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; COAL; DISSOLUTION; COAL LIQUIDS; FILTRATION; COAL LIQUEFACTION; PARTICLE SIZE; CARBONACEOUS MATERIALS; ENERGY SOURCES; FOSSIL FUELS; FUELS; LIQUEFACTION; SEPARATION PROCESSES; SIZE; THERMOCHEMICAL PROCESSES; 010405* - Coal, Lignite, & Peat- Hydrogenation & Liquefaction; 010402 - Coal, Lignite, & Peat- Purification & Upgrading

Citation Formats

Gilliam, T.M., Brand, J.I., and Rodgers, B.R. Coal dissolution studies: particle size distribution in coal-derived liquids as a function of degree of coal conversion. United States: N. p., 1979. Web. doi:10.2172/6277886.
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Gilliam, T.M., Brand, J.I., & Rodgers, B.R. Coal dissolution studies: particle size distribution in coal-derived liquids as a function of degree of coal conversion. United States. doi:10.2172/6277886.
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Gilliam, T.M., Brand, J.I., and Rodgers, B.R. Tue . "Coal dissolution studies: particle size distribution in coal-derived liquids as a function of degree of coal conversion". United States. doi:10.2172/6277886. https://www.osti.gov/servlets/purl/6277886.
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@article{osti_6277886,
title = {Coal dissolution studies: particle size distribution in coal-derived liquids as a function of degree of coal conversion},
author = {Gilliam, T.M. and Brand, J.I. and Rodgers, B.R.},
abstractNote = {Exploratory studies were conducted to assess the effect of the degree of coal conversion (i.e., a decrease in the amount of pyridine insolubles) in reacted coal - athracene oil mixtures. Particle size distribution data on the reacted mixtures show that the percentage of particulates < 10 ..mu.. in diameter increases gradually with conversion up to a conversion of about 85%. At higher conversions, the percentage of particulates < 10 ..mu.. in diameter increases dramatically in a near-step, function-like manner. The presence of small particulates are known to be a major cause of the low-filtration rates of coal liquefaction streams. Filtration experiments on the mixtures confirm that a relationship exists between filtration rates and conversion. Thus, the results of this work bear directly on the optimal design of two-stage liquefaction processes and could lead to improved design of processes such as SRC-I.},
doi = {10.2172/6277886},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue May 01 00:00:00 EDT 1979},
month = {Tue May 01 00:00:00 EDT 1979}
}
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DOI:  10.2172/6277886
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  • ; ;
    Particle size distribution data on slurries of reacted coal-anthracene oil mixtures indicate that the fraction of particles with diameters <10 ..mu.. increases steadily to 20% at a conversion of 85%; at higher conversions, it increases very rapidly to 60%. Filtration of the slurries suggests a relationship between overall filtration rate and conversion.

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  • The following activities in regard to the development of micromolecular probe distillation in combination with field-ionization mass spectrometry (FI/MS) for quantitative analysis are reported. The temperature-control module for the direct-introduction probe was received and successfully interfaced to both the probe and the NOVA 3/12. Both temperatures and FI/MS data were minicomputer acquired for probe distillation of a 19 component synthetic blend, a asphaltene-acid fraction, and the base fraction from an anthracene-oil sample. The acquired temperatures and FI/MS data for the 19 component blend were processed on the IBM 370/158 to obtain a quantitative distribution which is in excellent agreement withmore » both the known composition and the one obtained from the FI/MS data acquired using the batch-inlet system for sample introduction. Development of algorithms for correlating the acquired temperatures with the acquired FI/MS data using the NOVA 3/12 and for preparing the correlated data for remote job entry to the IBM 370/158 were initiated. The DS-50S data acquisition system/CEC 21-110B double-focusing mass spectrometer combination was extensively utilized to acquire (1) sensitivities for field ionization of saturates and aromatics, (2) FI/MS data for determining the weight percents of the individual homologs present in the aromatic fractions from the oils and asphaltenes isolated from a COED liquid, (3) FI/MS data for the quantitative analysis of GPC fractions obtained from separation of a hydrotreated shale oil, and (4) FI/MS data for the molecular-ion group-type analysis of saturate fractions from petroleum and shale oil.« less