Mass spectrometry study of lignocellulosic biomass combustion and pyrolysis with NOx removal

Herein, a study of the thermal combustion/pyrolysis behaviour of three lignocellulosic biomass materials was tested. Alongside this, an investigation on the reduction of the subsequently produced pollution emissions was carried out. The lignocellulosic biomasses (miscanthus x giganteus, orange peel waste (OPW) and potato peel waste (PPW)) were physiochemically characterised, along with in-situ gas detection from the combustion/pyrolysis processes. XRD and EDX results showed high level of inorganic salts in the bulk and surface of the samples tested, which had an impact on the combustion/pyrolysis behaviour. Among the three lignocellulosic biomasses tested, OPW showed the highest higher heating value of 17.88 MJ Kg(-1), whereas potato ash was the best candidate as a potential source of potassium (23.8 wt%) to be used in the fertiliser industry. The EDX results showed that miscanthus was the only lignocellulosic biomass to show high % Si in the surface composition. This was the reason for the low-temperature melting due to the formation of low fusion-temperature silicate as a result of SiO2, K, Cl and S. Pyrolysis experiments were conducted under pure nitrogen atmosphere, where hydrogen gas was observed in the temperature range of 580-700 degrees C. Combustion experiments were run under air where NOx emissions are generated during the combustion process. To mitigate those emissions, coupling the DeNOx catalyst with urea to construct an in-situ NH3-SCR system during the combustion achieved low levels of NOx emissions. (C) 2019 Elsevier Ltd. All rights reserved.