CFD approach of growing CU-particles in a 'Kenics' static mixer reactor

Waste-to-waste technology can be used for the reduction of heavy metals to their metallic state with carbohydrates. The carbohydrate waste originates from the pulp or food industry. Heavy metals in the form of Cu(II) are found in wastewater from the IC-manufacturers or mine leaches. A CFD approach is used in order to develop the reactor and to determine the right reactor conditions. A uniform size distribution of the particles which are formed in the process increases the economical value of the end product. A Kenics static mixer is used to optimize the flow inside the reactor. The growth of the copper particles is investigated by Monte Carlo simulations inside the static mixer. Fluent v5.5 unstructured was used to calculate the laminar flow field (Reynolds 50-500), Cu(II) concentration and particle tracks. The resulting flow field was validated by a grid independence check and a comparison with PIV experiments. It was found that the hydrodynamics of the mixer have a profound influence on the size distribution and the 'best' results were achieved at Reynolds 200.