A kinetic model for thermal cracking of waste cooking oil based on chemical lumps

• Published in: Fuel (Guildford) Vol. 144; pp. 50 - 59
• Main Authors: Meier, H.F., Wiggers, V.R., Zonta, G.R., Scharf, D.R., Simionatto, E.L., Ender, L.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.03.2015
• Subjects: Bio-oil; Frying oil; Kinetic model; Pyrolysis; Scale-up; Triglycerides; Pyrolysis; Kinetic model; Triglycerides; Frying oil; Bio-oil; Scale-up
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2014.12.020

[Display omitted] •Waste cooking oil was subjected to thermal cracking at three temperatures (475, 500 and 525°C).•Experiments were performed in a continuous tubular reactor varying the residence time (5–70s).•A four-lump kinetic model was used to represent the thermal cracking.•Reaction orders, activation energies and kinetic constants are reported. Thermal cracking or fast pyrolysis of waste cooking oil (WCO) was performed in a continuous pilot plant operating under isothermal conditions. The experiments were carried out varying the temperature (475, 500 and 525°C) and the residence time (5–70s) to obtain experimental data in order to construct a kinetic model based on chemical lumps. The kinetic model of the waste cooking oil is based on four lumps, defined according to the number of carbon atoms in the carbon chain, determined by gas chromatography, distributed as: waste cooking oil (WCO) (>C18); heavy bio-oil (HBO) (C12–C18); light bio-oil (LBO) (C4–C11); and bio-gas (BG) (<C4). The dependence of the kinetic rates on the composition and temperature considering the proposed mechanism was subjected to regression and the kinetic parameters (reaction order, frequency factor and activation energy) were determined and good agreement was observed. The proposed kinetic model could be used for future scaling-up studies and process development, aimed at the industrial application of the thermal cracking of waste cooking oil for the production of biofuels and renewable chemicals.