Dr.-Ing. Joern Viell is group leader of bioprocess development at the chair for Process Systems Engineering (AVT.SVT). His interdisciplinary scientific expertise focusses on biorefinery process development from experiment to processes. This includes experiments at lab-scale, development of process analytics and process simulation. Process analytical techniques are important for parameter identification and mechanistic understanding. In his group, spectroscopy is being used for in-situ process monitoring of biorefinery processes and model-based data evaluation. The process design includes screening for alternative process routes, rigorous process simulation and process analysis for optimal process development. Additionally, Joern is CEO of the biorefinery competence center in the Next Generation Centre for Processes and Products (NGP2), providing modular unit operations to investigate phenomena associated with scale-up and closed-recycle operation at technical scale. His expertise includes design, acquisition, operation and project management of the pilot facility.