Experimental analysis of the effect of the physicochemical properties of paper industry wastes on the performance of thermo-conversion processes: combustion and gasification

This work analyzes the energy performance implications of the physicochemical properties and the mineralogical elemental composition of agro-industrial wastes in the form of pellets (ISR pellets) and pine bark chips (PBCh). ISR pellets were made from a mixture of industrial wastewater treatment plant (IWTP) primary sludge, coal boiler ashes (CBA), and wood waste chips (WW), which are wastes rich in inorganic material and with a usable energy potential. All these residues were obtained from the production processes of paper company (Smurfit Kappa Colombia). ISR pellets and PBCh were tested as individual and mixed fuels in the thermochemical gasification and combustion processes. Several synergistic effects were found through the co-processing of these fuels, resulting in improvements in the performance indices normally used for the energy assessment of waste, as well as substantial environmental impact and operational behavior improvements. These effects were predicted through fusibility correlations from the elemental composition of the inorganic content, particularly the low melting point salts precursor species and fusibility temperature, as developed for coal ashes. The results of experimental co-processing validated these predictions.