The aim of chemical engineering and its unit operations is to transform raw materials into products (e.g. commodity and specialty chemicals like pharmaceuticals). However, motivated by the awareness of the world’s finite resources, it is desirable that these products are obtained in a sustainable, efficient and environmentally acceptable fashion, which means minimising waste and energy use, and make increasingly use of renewable raw materials. Novel efficient manufacturing technologies, flexible chemical plants, integrated process development, and innovative design approaches will provide the solutions to this important challenge.To reach these goals further research efforts in process intensification are needed, and there is also the demand for novel concepts for continuous reaction systems. Furthermore, many of the relevant chemical transformations involve multiphase flow, either gas-liquid, immiscible liquids, or solid-liquid. Thus, to successfully design these novel continuous reaction systems a detailed understanding of multiphase flow systems and the underlying physics of the transport processes associated with the various length scales is needed.Therefore, the aim of the proposed research is to understand interfacial transport processes and the scale-up of the involved transport coefficients in more detail. This is accomplished by identifying the physical mechanisms of heat and mass transfer on the micro- and milli-scale using non-invasive, laser-optical measurement techniques, and to use these experimental results to develop predictive multiphase flow models for computational fluid dynamics (CFD). The obtained results will bridge the gap between the micro- and milli-scale, and will directly impact the efforts in process intensification and sustainable advanced manufacturing.