This study aims to understand the effect of pyrolysis temperature on the conversion of nitrogen species of pig compost containing a large amount of nitrogen. Various analysis techniques involving thermogravimetry, X-ray photoelectron spectroscopy, nuclear magnetic resonance, gas chromatography, total nitrogen analysis, and ion chromatography were performed to characterize the nitrogen conversion of pig compost. Pyrolysis of the sample was carried out in a fixed bed reactor by varying the temperature from 300 to 900°C. The nitrogen content of the residue was found to decrease with increasing pyrolysis temperature. In contrast, the conversion of organic-nitrogen species into N
2 and NO
x-precursors (HCN and NH
3) increased with increasing temperature. The significant release of NH
3 below 500°C can be related to the high protein content in the pig compost. The nitrogen yield as HCN was lower than 2% during pyrolysis below 500°C, and sharply increased to 4% at 900°C due to thermal cracking of pyrrole and pyridine in the residual char at high temperature. A majority of the nitrogen species in residual char is converted into N
2 during pyrolysis above 700°C.
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