Release of NO from the combustion of coal chars
1996; Elsevier BV; Volume: 107; Issue: 4 Linguagem: Inglês
10.1016/s0010-2180(96)00080-6
ISSN1556-2921
AutoresA. W. Harding, Stephen D. Brown, K. Mark Thomas,
Tópico(s)Coal Properties and Utilization
ResumoThe emissions of nitrogen oxides during coal combustion contribute to acid rain and are a major environmental problems. In this investigation, the release of nitric oxide during the combustion of coal chars prepared from a wide range of coals in an entrained flow reactor was investigated over a range of combustion temperatures (823–1323 K) using a thermogravimetric analyzer coupled with a mass spectrometer. The conversion of char nitrogen to NO (NO/char-N) was studied in relation to coal and char structural characterization parameters. The results show that higher levels of conversion of char-N to NO were observed for the high-rank coal chars at lower combustion temperatures, where the reaction is under chemical control. As the combustion temperature increased, there was a decrease in the NO/char-N conversion ratio. Chars with low surface areas and low reactivities tend to have higher levels of conversion of char-N to NO during combustion. The implications for the mechanism of NO reduction on the char surface and in the pores are discussed.
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