Rheology of acid suspensions containing cassava bagasse: Effect of biomass loading, acid content and temperature

• Published in: Powder technology Vol. 354; pp. 271 - 280
• Main Authors: Polachini, Tiago Carregari, Mulet, Antonio, Cárcel, Juan A., Telis-Romero, Javier
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01-09-2019; Elsevier BV
• Subjects: Acids; Apparent viscosity; Arrhenius-type equation; Bagasse; Biomass; Cassava; Conversion; Equilibrium flow; Flow resistance; Herschel-Bulkley model; Lignin; Lignocellulose; Phosphoric acid; Residual starch; Rheological properties; Rheology; Shear thinning (liquids); Shear-thinning; Solids; Starch; Temperature dependence; Yield stress; Residual starch; Shear-thinning; Lignocellulose; Apparent viscosity; Herschel-Bulkley model; Arrhenius-type equation
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2019.05.086

Understanding the characterization and rheological behavior of acid suspensions of cassava bagasse provides essential information for the design of conversion processes. Samples with different cassava bagasse concentrations (0–10% w∙w−1), phosphoric acid (0–10% w∙w−1) at temperatures between 278.13 and 318.13 K were submitted to steady-state flow over a wide range of shear rates (1–265 s−1). The biomass particles had considerable residual starch (~50% db), low lignin content and adequate particle size (<200 μm) for the conversion process. Flow curves were well-fitted to the Herschel-Bulkley model, presenting a Newtonian domain at low solids and acid content and a non-Newtonian behavior with noticeable yield stress and shear-thinning characteristic (n < 1) at above 6% of cassava bagasse. Resistance to flow increased as the solids loading and acid content increased. Temperature dependence could be expressed as a function of an Arrhenius-type equation with good accuracy of fit.
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•Cassava bagasse was chemically and physically characterized.•Rheological behavior of acid suspensions was studied and modelled.•Biomass and acid concentration and temperature influenced the rheological parameters.•Non-Newtonian behavior was observed above 6% of solids in the suspensions.•Empirical and theoretical models could be well-fitted to experimental data.