Synergistic effect and volatile emission characteristics during co-combustion of biomass and low-rank coal

Abstract

Mass loss behaviours, volatile emissions (NO, HCN, NH3, CO, and CO2), and the O2 consumption characteristics during co-combustion of Naomaohu coal (NMH coal) and pine sawdust (PS) are studied using a TG-FTIR and a specially designed fixed-bed reactor. The results reveal that the trends of CO and CO2 in the TG-FTIR and fixed bed reactor results were similar, while the NO trends showed opposite behavior. In an inert atmosphere, there was no significant interaction during co-combustion of NMH coal and PS. However, a synergistic effect was observed under air atmosphere, leading to enhanced oxidation reactions and a notable reduction in ignition time. Specifically, the ignition time of NMH coal reduced from 5 s to 0.5 s when PS was added in the proportion of 75 %. Furthermore, the replacement of 25 % NMH coal with PS resulted in an 8.9 % reduction in NO emissions. This research provides a valuable framework for the thermal conversion of blends consisting of lignocellulosic biomass and low-rank coal.