Study of the Effect of Drying on the Pore Structure and Rate of Oxygen Consumption and Heat Release of Immersed Lignite

To reveal the influence mechanism of the drying process of immersed coal on the spontaneous combustion characteristics, we measured the pore structure of coal with low-field nuclear magnetic resonance and conducted the temperature-programmed spontaneous combustion experiment. The results showed that...

Full description

Saved in:
Bibliographic Details
Main Authors: Wei Guo, Chunhua Zhang, Ziwen Dong, Yongliang Han
Format: Article
Language:English
Published: Wiley 2023-01-01
Series:Geofluids
Online Access:http://dx.doi.org/10.1155/2023/5485324
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850237581991608320
author Wei Guo
Chunhua Zhang
Ziwen Dong
Yongliang Han
author_facet Wei Guo
Chunhua Zhang
Ziwen Dong
Yongliang Han
author_sort Wei Guo
collection DOAJ
description To reveal the influence mechanism of the drying process of immersed coal on the spontaneous combustion characteristics, we measured the pore structure of coal with low-field nuclear magnetic resonance and conducted the temperature-programmed spontaneous combustion experiment. The results showed that the pore volume content of the pores with pore sizes of less than 100 nm was significantly reduced. The diameter range of 100–1000 nm was gradually generated after 8 h of coal drying, and the proportion of large pores and cracks larger than 1000 nm increased significantly during the drying process of the immersed coal. The oxygen consumption rate and the heat release rate were significantly affected by the degree of dryness and the temperature of coal samples in the temperature-programmed process. The turning point temperature was 140°C; below the turning point temperature, the raw coal had the fastest oxygen consumption and maximum heat release. When the coal temperature was higher than 140°C, the oxygen consumption rate and the heat release rate of the coal sample that was dried for 24 h were higher than those for the raw coal, followed by the samples that were dried for 8 h and dried for 48 h. The main reason is that the water content of the coal sample decreases to 11.4% and the porosity increases to 16.5% after drying for 24 h, while the proportion of pores or cracks larger than 1000 nm increases significantly to 87.17%, the largest increase range and the pore connectivity will reach the maximum.
format Article
id doaj-art-12f4814da9f6434a8904cdcdad61523d
institution OA Journals
issn 1468-8123
language English
publishDate 2023-01-01
publisher Wiley
record_format Article
series Geofluids
spelling doaj-art-12f4814da9f6434a8904cdcdad61523d2025-08-20T02:01:42ZengWileyGeofluids1468-81232023-01-01202310.1155/2023/5485324Study of the Effect of Drying on the Pore Structure and Rate of Oxygen Consumption and Heat Release of Immersed LigniteWei Guo0Chunhua Zhang1Ziwen Dong2Yongliang Han3College of Safety Science and EngineeringCollege of Safety Science and EngineeringSchool of Safety EngineeringChina Coal Technology & Engineering Group Xi’an Research InstituteTo reveal the influence mechanism of the drying process of immersed coal on the spontaneous combustion characteristics, we measured the pore structure of coal with low-field nuclear magnetic resonance and conducted the temperature-programmed spontaneous combustion experiment. The results showed that the pore volume content of the pores with pore sizes of less than 100 nm was significantly reduced. The diameter range of 100–1000 nm was gradually generated after 8 h of coal drying, and the proportion of large pores and cracks larger than 1000 nm increased significantly during the drying process of the immersed coal. The oxygen consumption rate and the heat release rate were significantly affected by the degree of dryness and the temperature of coal samples in the temperature-programmed process. The turning point temperature was 140°C; below the turning point temperature, the raw coal had the fastest oxygen consumption and maximum heat release. When the coal temperature was higher than 140°C, the oxygen consumption rate and the heat release rate of the coal sample that was dried for 24 h were higher than those for the raw coal, followed by the samples that were dried for 8 h and dried for 48 h. The main reason is that the water content of the coal sample decreases to 11.4% and the porosity increases to 16.5% after drying for 24 h, while the proportion of pores or cracks larger than 1000 nm increases significantly to 87.17%, the largest increase range and the pore connectivity will reach the maximum.http://dx.doi.org/10.1155/2023/5485324
spellingShingle Wei Guo
Chunhua Zhang
Ziwen Dong
Yongliang Han
Study of the Effect of Drying on the Pore Structure and Rate of Oxygen Consumption and Heat Release of Immersed Lignite
Geofluids
title Study of the Effect of Drying on the Pore Structure and Rate of Oxygen Consumption and Heat Release of Immersed Lignite
title_full Study of the Effect of Drying on the Pore Structure and Rate of Oxygen Consumption and Heat Release of Immersed Lignite
title_fullStr Study of the Effect of Drying on the Pore Structure and Rate of Oxygen Consumption and Heat Release of Immersed Lignite
title_full_unstemmed Study of the Effect of Drying on the Pore Structure and Rate of Oxygen Consumption and Heat Release of Immersed Lignite
title_short Study of the Effect of Drying on the Pore Structure and Rate of Oxygen Consumption and Heat Release of Immersed Lignite
title_sort study of the effect of drying on the pore structure and rate of oxygen consumption and heat release of immersed lignite
url http://dx.doi.org/10.1155/2023/5485324
work_keys_str_mv AT weiguo studyoftheeffectofdryingontheporestructureandrateofoxygenconsumptionandheatreleaseofimmersedlignite
AT chunhuazhang studyoftheeffectofdryingontheporestructureandrateofoxygenconsumptionandheatreleaseofimmersedlignite
AT ziwendong studyoftheeffectofdryingontheporestructureandrateofoxygenconsumptionandheatreleaseofimmersedlignite
AT yonglianghan studyoftheeffectofdryingontheporestructureandrateofoxygenconsumptionandheatreleaseofimmersedlignite