ef6b01255_si_001.pdf (154.61 kB)
Influences of Hydrothermal Modification on Nitrogen Thermal Conversion of Low-Rank Coals
journal contribution
posted on 2016-09-06, 00:00 authored by Qian Li, Zhihua Wang, Zhenmin Lin, Yong He, Kang Zhang, Ronald Whiddon, Kefa CenThe
influence of hydrothermal modification on thermal conversion
of coal-N in low-rank coals was investigated in this paper. Hydrothermal
modification has been performed using three typical Chinese low-rank
coals at final modification temperatures of 200, 250, and 300 °C.
An analytical pyro-probe coupled to a pyrolysis–gas chromatography
mass spectrometry (Py-GC/MS) system was used to study the release
characteristics of nitrogen-containing compounds from raw and modified
coal. In addition, a tube furnace apparatus was used to study the
release characteristics of nitrogen pollutants during pyrolysis and
combustion of Zhaotong raw and modified coal. Results showed that
hydrothermal modification affected the content and type of nitrogen-containing
compounds. Some triple bonds present in the coal structure are broken
to form amides. The presence of azoles decreases sharply after modification,
but it increases as the hydrothermal modification temperature increases.
During tube furnace pyrolysis, the HCN yield decreases after modification;
similarly, with the increase of modification temperature, NH3 is released in greater quantity after modification, but the release
decreases as the modification temperature increases. NH3 may be converted from HCN through secondary reactions. Hydrothermal
modification is conducive to NO emission reduction in coal combustion
process; however, increasing the modification temperature restrains
the NO emission to some extent.
History
Usage metrics
Categories
Keywords
hydrothermal modificationhydrothermal modification temperature increasestube furnace apparatusChinese low-rank coalsHydrothermal modificationHCNNH 3nitrogen-containing compoundsmodification temperaturerelease characteristicstube furnace pyrolysiscoal combustion processmodification temperature increases
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC