Pelletization of invasive Reynoutria japonica with spruce sawdust for energy recovery

The article focuses on processing of Reynoutria japonica an invasive alien species that is generally extirpated with major costs for its negative impact on biodiversity. It is the biodegradable waste that could be effectively used in energy industry. By examining first energy data (ash content, low melting temperature, nitrogen content etc.) it was found that Reynoutria japonica is not possible to be used separately for energy purposes. Therefore, the alternative of pelletizing six mixtures containing Reynoutria japonica and spruce sawdust in various content ratio was examined with the aim to produce alternative fuel pellets for automated boilers. The pelletization conditions were determined and the pellets quality was evaluated (durability, density etc.). Ash melting temperature was also evaluated. It was found none of the prepared mixtures needed an additional binder for a pelletizing process. It was assessed that the Reynoutria japonica input sample did not need to be dried after collection, since its moisture was sufficient for the pelletization. All samples met the parameters of the calorific value, which is greater than 10 MJ.