Flow characteristics of biomass particles in a horizontal stirred bed reactor: Part II. Modeling studies on particle residence time distribution and axial mixing

•We obtained the axial dispersion coefficients based on the experimental results.•The axial mixing was investigated using the axial dispersion coefficient.•We proposed correlations for the axial dispersion model parameters in the HSBR.•The empirical model validity was verified.•The RTD in the HSBR was modeled with different conditions.

The modeling investigation of the flow and mixing behavior of particles in the horizontal stirred bed reactor was conducted using the axial dispersion model. The axial dispersion coefficients were obtained with different operational and design parameters and flow properties, based on the measured residence time distribution (RTD) in Part I. The axial mixing is considerably enhanced with the increase of the rotation rate, the number of blades and the repose angle. The flow rate made a less important contribution to the variation of the axial mixing while the blade angle rarely affected the axial mixing. This work proposed new design correlations for the model parameters in terms of flow rate, rotation rate, flow properties of materials, number of blades and blade angle, obtained by means of multiple regressions. The model developed in this paper was proved sufficiently accurate to model the RTD of particles in the HSBR by comparison between the numerical simulation and the experimental result of the RTD curve. The simulation of the RTD of particles in the HSBR was then performed with different conditions to investigate the effect of various parameters on the RTD using the model and gave similar trends with the experimental results.

Graphical abstractThe modeling investigation of the flow and mixing behavior of biomass particles in the horizontal stirred bed pyrolysis reactor was conducted using the axial dispersion model.Figure optionsDownload full-size imageDownload as PowerPoint slide