Abstract
Pyrolysis and combustion experiments of dried sewage sludge were conducted using an electrically heated drop furnace to elucidate NOx formation/destruction characteristics. When the dried sewage sludge was fed into the drop furnace, the particle temperature rose rapidly and the particles swelled. The char particle structure became balloon-like. Regarding NOx formation, both NO and N2O were formed during combustion. After N2O was generated in the flame, NO was produced because N2O was destroyed by H radicals formed by CO oxidation. Although conversion of fuel-N into N2O decreased with increased furnace temperature, conversion of fuel-N into NO increased. The N2O conversion ratio of the dried sewage sludge was higher than that of the sample coal because the dried sewage sludge emits more HCN, which more readily produces N2O.
