Evaluation of the pyrolysis of biodiesel filtration residue containing diatomite by thermal analysis

Sludges are complex mixtures containing water, inorganic and organic residues, being generated at different stages of industrial processes. Due to their characteristics, they are considered hazardous wastes, and to recover their organic components, Multiphase Residue Thermal Treatment Technology (TTRM®) can be used, which is an alternative for treatment and recovery of wastes containing also large amounts of water in their composition. In the present study, samples of a residual sludge obtained from biodiesel filtration with diatomite were analyzed before and after being processed in a TTRM reactor. Thermogravimetry, derivative thermogravimetry and differential thermal analysis were used to estimate the pyrolysis yield, the carbonaceous residue content formed throughout the process and the energy demand. The results have shown an estimated yield of approximately 80 % during pyrolysis, a maximum content of 6 % carbonaceous residue and a 197.48 kJ kg−1 energy demand to pyrolize the sludge.