ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Chemistry and Emissions of Nitrogen Oxides (NO, N0₂ , N₂0) in Combustion of Solid Fuels II. Heterogeneous Reactions — N₂0

K. Svoboda, J. Čermák, and M. Hartman

Institute of Chemical Process Fundamentals, Academy of Sciences of the Czech Republic, CZ-165 02 Prague

Abstract: Nitrous oxide (N₂0) volume fractions in atmosphere increase at an estimated rate 0.7-0.8 ppb per year. Potential anthropogenic sources of N₂0 include fertilization, combustion, mobile (car) sources, and atmospheric transformation of NOx to N₂0. Combustion of solid fuels and waste at lower temperatures (750-900 °C) presents a significant source of N₂0. During stages of a coal particle combustion (pyrolysis-devolatilization and char combustion) both volatile N and char N are mainly transformed to N₂ + NO and partly to N₂0. HCN was recognized as the main precursor of N₂0 in volatile combustion. Char-N conversion to N₂0 (through various mechanisms) is affected by in seiu reduction of N₂0 by carbon surface and CO.Temperature has the most important effect on N₂0 emissions. At temperatures over 1000°C the N₂0 emissions are negligible. Char and CaO are in practical combustion systems the most effective catalysts for thermal decomposition of N₂0.

Full paper in Portable Document Format: 542a118.pdf

Chemical Papers 54 (2) 118–130 (2000)