Wet granulation in dense particulate high-shear systems

Research Project, 2011 – 2013

Wet granulation is a widely used process step in processing of minerals, agricultural products, food, speciality chemicals, and specifically in the development and manufacturing of tablets in the pharmaceutical industry. In this step dry powders are being mixed and granules (agglomerates) are formed when a binder solution is added. Granulation in high-shear mixers, which are commonly used in the pharmaceutical industry, is the focus of the present study. Important properties of the granules are particle size and distribution, moisture content, homogeneity, bulk density, porosity and mechanical strength. The over-all goal of the present project is to develop experimental and theoretical methods to describe multi-dimensional evolution of agglomerates using population balances; flow in dense particle systems; and coupling between flow and population balance models. Specifically we will develop mathematical models for high-shear wet granulation to be used for design, scale-up, operation, control and optimization of tabletting formulations in high-shear mixers. This is of high relevance for the pharmaceutical industry and requires a coupling between models at the particle level (population balances) with models for the flow- and shear-fields. The models will be experimentally verified, partly in equipment at AstraZeneca in Mölndal.