Nitrogen conversion under rapid pyrolysis of two types of aquatic biomass and corresponding blends with coal

► Aquatic biomass and biomass/coal blends were pyrolyzed in a high-frequency furnace. ► For aquatic biomass, char-N yields are low, and much more NH3 than HCN are formed. ► Interactions between biomass and coal decrease char-N and NH3 + HCN yields. ► Blue-green algae have higher reactivity to promote nitrogen release from coal. ► Lignin may causes polymerizations to promote NH3 formation under low temperature.