Understanding the unusual fluidity characteristics of high ash Indian bituminous coals

High-temperature rheometry and 1H nuclear magnetic resonance (NMR) are two complementary techniques that have been used to investigate fluidity development quantitatively in the < 53 µm and 53-212 µm size fractions of high ash Indian non-coking coals and imported non-coking, medium coking and goo...

Full description

Bibliographic Details
Main Authors: Das, Bidyut, Suresh, A, Dash, P.S., Chandran, S., Castro-Díaz, M., Stevens, Lee A., Snape, Colin E.
Format: Article
Published: Elsevier 2018
Subjects:
Online Access:https://eprints.nottingham.ac.uk/51068/
_version_ 1848798406778028032
author Das, Bidyut
Suresh, A
Dash, P.S.
Chandran, S.
Castro-Díaz, M.
Stevens, Lee A.
Snape, Colin E.
author_facet Das, Bidyut
Suresh, A
Dash, P.S.
Chandran, S.
Castro-Díaz, M.
Stevens, Lee A.
Snape, Colin E.
author_sort Das, Bidyut
building Nottingham Research Data Repository
collection Online Access
description High-temperature rheometry and 1H nuclear magnetic resonance (NMR) are two complementary techniques that have been used to investigate fluidity development quantitatively in the < 53 µm and 53-212 µm size fractions of high ash Indian non-coking coals and imported non-coking, medium coking and good coking coals. It was found for the 53-212 µm size fraction of the Indian bituminous coal with higher ash content (30 wt%) that, despite its high complex viscosity (> 105 Pa.s), the maximum concentration of fluid H was quite similar to that of the good coking coal (40%). This Indian non-coking coal developed fluid H with the greatest mobility (T2L > 150 μs) in the coal series, regardless of the particle size fraction studied. The probable explanation for this abnormal behavior is that the mineral matter prevents bulk movement in the sample but the local mobility of the fluid phase is still high on the nanometer scale. Blending the two Indian non-coking coals with the highly fluid medium coking coal gave higher viscosities (i.e. lower fluidity) than predicted by the polymer blend rule, probably again due to the high mineral matter restricting bulk flow. This negative effect was less pronounced with the higher ash coal suggesting that the high mobility of the fluid entities in this coal might prevent the destruction of fluid entities evolving from the medium coking coal. Partial demineralization of the high ash Indian non-coking coal to 17 wt% through a sink-float method did not decrease the complex viscosity of this coal but reduced the maximum mobility of the fluid H to levels observed with the lower ash content (20 wt%) Indian coal. Therefore, this reduction in mobility could be directly related to the mineral matter in the Indian non-coking coal.
first_indexed 2025-11-14T20:19:16Z
format Article
id nottingham-51068
institution University of Nottingham Malaysia Campus
institution_category Local University
last_indexed 2025-11-14T20:19:16Z
publishDate 2018
publisher Elsevier
recordtype eprints
repository_type Digital Repository
spelling nottingham-510682020-05-04T19:47:37Z https://eprints.nottingham.ac.uk/51068/ Understanding the unusual fluidity characteristics of high ash Indian bituminous coals Das, Bidyut Suresh, A Dash, P.S. Chandran, S. Castro-Díaz, M. Stevens, Lee A. Snape, Colin E. High-temperature rheometry and 1H nuclear magnetic resonance (NMR) are two complementary techniques that have been used to investigate fluidity development quantitatively in the < 53 µm and 53-212 µm size fractions of high ash Indian non-coking coals and imported non-coking, medium coking and good coking coals. It was found for the 53-212 µm size fraction of the Indian bituminous coal with higher ash content (30 wt%) that, despite its high complex viscosity (> 105 Pa.s), the maximum concentration of fluid H was quite similar to that of the good coking coal (40%). This Indian non-coking coal developed fluid H with the greatest mobility (T2L > 150 μs) in the coal series, regardless of the particle size fraction studied. The probable explanation for this abnormal behavior is that the mineral matter prevents bulk movement in the sample but the local mobility of the fluid phase is still high on the nanometer scale. Blending the two Indian non-coking coals with the highly fluid medium coking coal gave higher viscosities (i.e. lower fluidity) than predicted by the polymer blend rule, probably again due to the high mineral matter restricting bulk flow. This negative effect was less pronounced with the higher ash coal suggesting that the high mobility of the fluid entities in this coal might prevent the destruction of fluid entities evolving from the medium coking coal. Partial demineralization of the high ash Indian non-coking coal to 17 wt% through a sink-float method did not decrease the complex viscosity of this coal but reduced the maximum mobility of the fluid H to levels observed with the lower ash content (20 wt%) Indian coal. Therefore, this reduction in mobility could be directly related to the mineral matter in the Indian non-coking coal. Elsevier 2018-07-31 Article PeerReviewed Das, Bidyut, Suresh, A, Dash, P.S., Chandran, S., Castro-Díaz, M., Stevens, Lee A. and Snape, Colin E. (2018) Understanding the unusual fluidity characteristics of high ash Indian bituminous coals. Fuel Processing Technology, 176 . pp. 258-266. ISSN 0378-3820 Non-coking coal high ash coal coal fluidity coal viscosity https://www.sciencedirect.com/science/article/pii/S0378382018301929 doi:10.1016/j.fuproc.2018.04.003 doi:10.1016/j.fuproc.2018.04.003
spellingShingle Non-coking coal
high ash coal
coal fluidity
coal viscosity
Das, Bidyut
Suresh, A
Dash, P.S.
Chandran, S.
Castro-Díaz, M.
Stevens, Lee A.
Snape, Colin E.
Understanding the unusual fluidity characteristics of high ash Indian bituminous coals
title Understanding the unusual fluidity characteristics of high ash Indian bituminous coals
title_full Understanding the unusual fluidity characteristics of high ash Indian bituminous coals
title_fullStr Understanding the unusual fluidity characteristics of high ash Indian bituminous coals
title_full_unstemmed Understanding the unusual fluidity characteristics of high ash Indian bituminous coals
title_short Understanding the unusual fluidity characteristics of high ash Indian bituminous coals
title_sort understanding the unusual fluidity characteristics of high ash indian bituminous coals
topic Non-coking coal
high ash coal
coal fluidity
coal viscosity
url https://eprints.nottingham.ac.uk/51068/
https://eprints.nottingham.ac.uk/51068/
https://eprints.nottingham.ac.uk/51068/