Eindhoven, North Brabant, Netherlands
I focus on the development of catalytic and non-catalytic multiphase reactors that use rotation to create high gravity and high shear conditions. These conditions lead to excellent interphase mass transfer, intraphase mixing, and fluid-to-wall heat transfer. Applications are especially in (exothermic) fast reactions that are interphase mass transfer limited, are mixing limited, or are heat transfer limited. Additionally, in a high gravity field two phases with different density can be contacted countercurrently. Thus, distillation (gas-liquid), extraction (liquid-liquid), and crystallization (liquid-solid) become feasible. The high-gravity high-shear conditions enable the use of extremely compact equipment for the chemical industry. The equipment is easily a factor hundred smaller than conventional equipment. The much smaller equipment size allows for the safe use of high temperatures and high pressures, enlarging the economic process window. An additional benefit of the small equipment size is that expensive construction materials and coatings can be used, with only a minor increase in equipment costs. The intensified technology will play an important role in chemical processes based on renewable energy: the fluctuations in energy availability become more and more considerable, which requires agile operation of distributed chemical processes, very different from the steady-state economy of scale paradigm. Solar power driven processes will be small scale (e.g. a 2 GWp solar field only produces ~0.1 kg/s of 'CH2' units by electrochemical reduction of CO2, not including energy needed for purification steps) with a highly variable load (from 0 kg/s to 0.6 kg/s). Small volume, high performance equipment can easily follow the energy availability. Future research focuses on the performance of high-gravity high-shear equipment as a function of design, operating conditions, and fluid properties. E.g. flow patterns, mixing intensity, interphase mass transfer, flooding point correlations are needed for proper design and optimization, preferably determined with industrially relevant systems. Also, the application for photochemistry and electrochemistry is researched. In education I am building a blended learning environment for the courses Basic and Advanced Reactor Engineering, where I want students to be able to study the course material individually, and where they also get tested automatically. This way, students can enroll the course when and where they want. They can do the (final) test when they want in a controlled environment at the university.
Responsible for Finance, HR, Research
Consultancy of glass manufacturers for prevention and breakdown of foam in furnaces.
Experimental validation of computational fluid dynamics codes for gas-solid fluidized beds, with emphasis on the dynamic behavior of the system.
Thesis title: "Dynamics of Gas-Solids Fluidized Beds - analysis of pressure fluctuations" The dynamic behavior of fluidized beds is characterized by time series analysis of pressure fluctuations. The pressure fluctuations are correlated to relevant physical phenomena in the bed, e.g. formation, rising, coalescence, and eruption of gas bubbles, turbulence, solids cluster size and velocity. The dynamic behavior is characterized by Fourier analysis and chaos analysis. The results are mathematically and experimentally shown to be similar. The Fourier analysis finally leads to a correlation for gas bubble diameter, that can be used for scaling up the fluidized bed.