Efect of Temperature on the Flow Profile of the Bio-oil Produced from the Fast Pyrolysis of Sisal Residue

The objective of this study was to evaluate the flow of a film of bio-oil in a cylindrical tube similar to the tube of a heat exchanger found in a fast pyrolysis unit of sisal residue in a fluidized bed. The velocity profile of bio-oil was determined from the momentum balance and the equation that describes the rheological behavior of the fluid. The rheological behavior of bio-oil was determined at 60, 70, 80, 90, and 110 °C, and eight models to describe the rheological behavior were evaluated. The Sisko, Herschel–Bulkley, Mizrahi−Berk and Robertson−Stiff models all performed similarly, and they adequately represented the rheological behavior of bio-oil with a pour point of 55 °C derived from sisal residue. The variation of the thickness of the bio-oil film on the walls of a cylindrical tube and the velocity profile in the film as a function of temperature were determined empirically using the four best rheological models. Only the equation of flow employing the rheological model of Sisko showed results c...