Energy Citations Database

Bibliographic Citation

 
Document
For copies of Journal Articles, please contact the Publisher or your local public or university library and refer to the information in the Resource Relation field.
For copies of other documents, please see the Availability, Publisher, Research Organization, Resource Relation and/or Author (affiliation information) fields and/or Document Availability.
DOI http://dx.doi.org/10.1021/ef960129n
Title In-situ{sup 1}H NMR investigation of particle size, mild oxidation and heating regime effects on plasticity development during coal carbonization
Creator/Author Maroto-Valer, M.M. ; Andresen, J.M. ; Snape, C.E. [University of Strathclyde, Glasgow (United Kingdom). Dept. of Pure and Applied Chemistry]
Publication Date1997 Jan 01
OSTI IdentifierOSTI ID: 453319
Other Number(s)ENFUEM; ISSN 0887-0624
Resource TypeJournal Article
Resource RelationEnergy and Fuels ; VOL. 11 ; ISSUE: 1 ; PBD: Jan-Feb 1997
Subject01 COAL, LIGNITE, AND PEAT ; BITUMINOUS COAL; CARBONIZATION; NUCLEAR MAGNETIC RESONANCE; HYDROGEN 1; PARTICLE SIZE; OXIDATION; HEATING RATE; PLASTICITY; COKING
Description/Abstract High-temperature in situ{sup 1}H NMR with a probe operating at a frequency of 100 MHz has been used to quantify the effects of particle size, mild oxidation, and different heating regimes on plasticity development for a low-volatile Australian bituminous coal in terms of the proportions of rigid and fluid material present. At the temperature of maximum fluidity, the fluid phase accounts for 35% of the hydrogen remaining, with both its concentration and mobility increasing up to this temperature. Reducing the particle size below ca. 150{mu} m suppresses plasticity through a reduction in the mobility of the fluid phase with the concentration of rigid material remaining constant. This effect is considerably more pronounced with slow heating than it is with fast heating (3-4 cf. 30{degree}C min{sup -1}). In contrast, suppressing the fluidity by mild oxidation reduces primarily the concentration of the fluid phase. Isothermal treatments give rise to a loss of fluidity due to reductions in both the proportion and mobility of the fluid component. The in-situ measurements have confirmed that plasticity development is a reversible phenomenon provided that relatively fast quenching rates (ca. 75{degree}C min{sup -1}) are used. These results are discussed in relation to estimating the contribution to fluidity development form the non-solvent-extractable material in coals. Heating coking coal in a tube furnace to the temperature of maximum fluidity followed by fairly rapid cooling is shown to be a simple procedure for recovering relatively large amounts of partially carbonized coal with the structural features responsible for maximum fluidity preserved. 57 refs., 11 figs., 4 tabs.
Country of PublicationUnited States
LanguageEnglish
Formatpp. 236-244 ; PL:
System Entry Date2001 May 05

Top