The thesis presents investigations on two-phase gas-liquid microstructured reactorsudoperating in Taylor flow and the dependence of reactor performance on designudparameters. Literature review revealed that flow patterns in microchannels are affectedudnot only by channel dimension, fluids flowrates and surface tension, but also by walludwettability and gas inlet size. A universal flow regime map does not seem to exist. Theudhydrodynamic parameters of Taylor flow were investigated both by ComputationaludFluid Dynamics simulations and experiments in microstructures with sizes 0.3mm –ud1mm and various inlet configurations such as T- and Y- junctions fabricated in-house.udThe same parameters that influence flow patterns and their transitions were also foundudto affect Taylor bubble sizes. To account for the effect of inlet conditions, correlationsudwere developed for predicting bubble/slug size in the T- and Y- inlet geometries thatudwere used subsequently. Mass transfer with and without chemical reaction wasudinvestigated numerically in Taylor flow microreactors using CO2 physical absorptionudinto water or chemical absorption into NaOH aqueous solution. Chemical absorptionudwas enhanced by a factor of 3-18 over physical absorption. With reaction present, theudreactor performance depended mainly on the gas-liquid interfacial area, while mixingudwithin the phases was only important in physical absorption. This agreed with theudexperimental results of a similar reaction system, which showed that bifurcating mainudchannels, where new interfaces are generated, significantly improved reactionudconversion while meandering channels that enhance liquid mixing had little impact.udFinally, the performance of a Taylor flow microreactor was evaluated for an industrialudfast gas-liquid reaction of CO2 absorption from fuel gas into amine solutions. TheudTaylor flow microreactor offered the largest specific area and the smallest reactorudvolume compared to other microreactor types. However, in order to meet absorptionudspecifications for the case considered multistage absorption would have been necessary.
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