A novel uncoupled quasi-3D Euler-Euler model to study the spiral jet mill micronization of pharmaceutical substances at process scale: model development and validation

In this work we present a novel approach to model the micronization of pharmaceutical ingredients at process scales and times. 3D single-phase fluid-dynamics simulations are used to compute the gas velocity field within a spiral jet mill which are provided as input in a 1D compartmentalized model to calculate solid velocities along the radial direction. The particles size reduction is taken into account through a breakage kernel that is function of gas energy and local solid hold-up. Simulation results are validated against micronization experiments for lactose and paracetamol, comparing the model predictions with D10, D50 and D90 diameters values coming from Design of Experiments isosurfaces. The developed model allows for a fair estimation of the outlet particle size distribution in a short computational time, with very good predictions especially for D90 values. [Display omitted] •A novel decoupled model is developed to study spiral jet milling at process-scales.•The model exploits CFD simulations and 1D compartment-based calculations.•Breakage parameters were defined availing of ad hoc micronization experiments.•The proposed strategy works for brittle and semi-brittle substances.•Model predictions are in good accordance with experiments.