Emissions of nitrogen oxides in pulverized peat combustion between 730 and 900 °C

• Published in: Fuel (Guildford) 1989, Vol.68 (5), p.586-590
• Main Authors: Aho, Martti J., Rantanen, Jarmo T.
• Format: Article
• Language: English
• Subjects: Air pollution caused by fuel industries; Applied sciences; Atmospheric pollution; combustion; Combustion and energy production; Combustion of solid fuels; Combustion. Flame; Energy; Energy. Thermal use of fuels; Exact sciences and technology; nitrogen compounds; peat; Pollution; Pollution reduction; Pollution sources. Measurement results; Theoretical studies. Data and constants. Metering
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/0016-2361(89)90154-3

Five Finnish peats were burned in an entrained flow reactor at temperatures between 730 and 900 °C to study the conversion of peat nitrogen to nitrogen oxides (N 2O, NO and NO 2) in conditions simulating low-temperature, unstaged pulverized fuel combustion. Oxygen content was varied between 1 and 18 %. The major product was NO (conversion of fuel-N to NO varied between 10 and 43%), but the concentration of N 2O was high at low temperatures and at 730 °C the degree of conversion of fuel-N to N 2O sometimes exceeded that of fuel-N to NO. Unlike NO, the formation of N 2O was not sensitive to oxygen content of the reaction environment, and it decreased with increasing O N ratio in the peat. This led to marked differences in the molar concentrations of N 2O in the flue gas from different peats between 730 and 800 °C. Particle sizes in the range 16–205 μm and moisture contents of 5–20% had no observed effect on fuel nitrogen conversions. Conversion of fuel-N to NO 2 was < 1%.