| Pelletization of coal fines generated from coal cleaning processes with lignin residue, was investigated in this work from low-temperature concentrated-acid hydrolysis of various lignocellulosic biomass feedstocks. Processing variables of pelletization temperature, pelletization time, pelletization pressure, moisture content and coal to lignin residue ratio for the pelletization study were examined through a 2-level design of experiments fabricated to determine the most important processing variables. The orthogonal design matrix also provided a measure of the importance of interactions between the processing variables during the pelletization. Another aspect of this work was the development of a qualitative assessment of the binding characteristics of lignin residues obtained from different feedstock materials. The results showed that pellet quality, defined by dusting loss and strength, could be improved by carrying out the pelletization at a lower moisture content (10%), lower pelletization temperature (300... |
