Thermal Oxidation Kinetics of the Solid Residues of Alcohol Distillery Effluents

Abstract

The thermal degradation studies of three types of residues obtained from the chemical treatment of distillery effluents were conducted in a thermogravimetric analyzer in the presence of air (flow rate: 200 ml/min) from the room temperature (25°C) to 950°C. The global mass loss kinetics was determined for the entire decomposition process, as if occurring in a single step. Among the various models used to understand the degradation studies, the Agrawal and Sivasubramanian model (1987) is found to fit best for CTR-1 and CTR-2 (thermolysis residues) with reaction order 0.89 and 1.43, respectively. For coagulation-flocculation residue, the Ginstling-Brounstein diffusion model best represents the kinetics. The activation energy is found to be in the range of 21–66 MJ/kg for CTR-1, 15–51 MJ/kg for CTR-2, and 12–27 MJ/kg for coagulation flocculation residue.

Keywords:

• catalytic thermolysis
• coagulation
• distillery wastewater
• oxidation kinetics
• residues
• thermal degradation