The Helix reactor is highly suited for precise reaction control based on good hydrodynamics. The hydrodynamics are controlled by the Dean vortices, which create excellent heat transfer properties, approach plug flow and avoid turbulence. The flexibility of this reactor has been demonstrated using a very exothermic, temperature sensitive alkylation reaction, a mechanically delicate emulsion polymerisation reaction and a precipitation reaction. It was demonstrated that the highly exothermic alkylation reaction could be controlled such that no side reactions occured. In the case of the emulsion polymerisation reaction the gentle mixing conditions of the Helix reactor were used to control the particle size and size distribution. Also for the precipitation reaction it was possible to obtain a narrow particle size distribution and to control the particle size. It can be concluded that the helix reactor is a versatile tool to perform reactions that are typically batch wise operated in a continuous way, and thereby reducing costs and improving safety and quality.@en

With chemical looping combustion (CLC), the condensation of water from the combustion product stream yields essentially pure CO2 that can be readily compressed for transport and storage. Using synthesis gas as fuel, fixed-bed CLC is studied with the optimization of systems ≤ 1 kw. The production of pure CO2 is optimized while the pressure drop over the reactor is minimized. The ability to have a sharp breakthrough of the fuel at the outlet of the reactor is an important parameter and the amount of pure CO2 that can be produced before contamination from the slip of fuel gives a measure of system performance. The total fuel required to complete a full reduction is another indicator of efficiency and has a logarithmic relationship with respect to the size of the reactor. Improvement in the bed design and choice of flow rates should decrease the dependence on scale. With results for three different sizes of reactors, optimal packing and operating conditions can be predicted for increasingly larger systems while being customized to specific applications. Future research implications are discussed. This is an abstract of a paper presented at the 2011 AIChE Spring Meeting & 7th Global Congress on Process Safety (Chicago, IL 3/13-17/2011).@en

Fixed-bed chemical looping combustion is currently being studied experimentally with the optimization of systems up to 1 kW. One of the key advantages for using the fixed-bed configuration over fluidized-beds is the flexibility in operating parameters that allows for application of CLC not only to power production, but also to niche applications, such as the decoupled production of heat and CO 2 for the greenhouse industry. Another advantage is the modularity of the systems that greatly simplifies scale-up once the optimal single reactor design is realized. This is currently being studied by optimizing the production of pure CO 2 while minimizing the pressure drop over the reactor. With results for three different sizes of reactors, optimal packing and operating conditions can be predicted for increasingly larger systems while being tailored to the specific application.@en