Efficient 1D Modelling of Hot Melt Extrusion Process for Pharmaceutical Applications

Hot melt extrusion (HME) involves the melting of materials and mixing and pushing of various solids under elevated temperature and pressure. It is a mature technology that has been extensively used for a broad spectrum of applications in the polymers, food, and pharmaceutical industries. HME can be a promising downstream processing method due to its high efficiency and economic value, however mathematical modelling of HME processes has always been challenging due to the limited understanding and the demanding experimental techniques. In this work, an 1D model is developed for the efficient simulation of the steady state and dynamic operation of HME processes. It is shown that the steady state operation can be described as a classical complementarity problem. The solution of the resulting complementarity problem can be performed efficiently in available software. The determination of the consistent initial conditions facilitates the solution of the system of differential and algebraic equations (DAEs).