270621 Flow Reactors: Development and Applications
Flow Reactors: Development and Applications
Anh N. Phan*, Adam P. Harvey, Valentine Eze and Martin Rawcliffe
School of Chemical Engineering & Advanced Materials, Claremont Road, NE1 7RU, Newcastle University
Several unique intensified reactors were constructed and characterised at low net flow rates (µl/min to ml/min, corresponding to net flow Reynolds number, Ren <50) that would be in the laminar flow regime if they were in steady (non-oscillatory) flow. It was demonstrated that that these reactors can easily achieve high degrees of plug flow at these net flow rates over a wide range of oscillation conditions. The oscillation conditions had a strong influence on the residence time distribution (RTD) at net flow Reynolds numbers, Ren < 10, but little effect on the RTD behaviour at Ren above 25. This leads to their niche application by converting long batch reactions to continuous operation with greatly reducing ratios of length to diameter.
Two phase liquid reaction such as biodiesel production was chosen as a case study for continuous screening. Methyl ester (biodiesel) was produced at a consistent quality and there were clear responses to variations in input conditions. A clear step-change between various steady state molar ratios of methanol to oil and dynamic screening was observed in these reactors. Rapid screening such as this has the potential to significantly reduce process development, operating costs and environmental impact. The methyl ester was above 96.5% within less than 10mins when operating in these intensified reactors compared to approximately 1hour when operating in conventional stirred tank reactors.
These reactors can be used in their own right as very small production platforms for high added-value chemicals, or to provide information for scale-up to pilot and industrial scale. These novel new designs are the basis of a revolutionary “process platform” that is being developed as a product to allow rapid continuous screening of processes at laboratory scale, with a view to reducing time-to-market for products and minimising usage of (perhaps expensive) feedstocks and production of waste. The platform is expected to be particularly useful in bioprocessing and pharmaceutical applications, such as fermentations, crystallizations and biotransformations.