SCALE-UP AND APPLICATION OF A CYCLONE REACTOR FOR FERMENTATION PROCESSES

\A cyclone reactor for microbial fermentation processes was developed with high oxygen transfer capabilities. Three geometrically similar cy clone reactors with 0.5 l, 2.5 l and 15 l liquid volume, respectively, were characterized with respect to oxygen mass transfer, mixing time and residence time distribution. Semi-empirically correlations for pre diction of oxygen mass transfer and mixing times were identified for s cale-up of cyclone reactors. A volumetric oxygen mass transfer coeffic ient k(L)a of 1.0 s(-1) (available oxygen transfer rate with air: 29 k g m(-3) h(-1)) was achieved with the cyclone reactor at a volumetric p ower input of 40 kW m-3 and an aeration gas flow rate of 0.2 s(-1). Co ntinuous methanol controlled production of formate dehydrogenase (FDH) with Candida boidinii in a 15 l cyclone reactor resulted in more than 100% improvement in dry cell mass concentration (64.5 g l(-1)) and in about 100% improvement in FDH space-time yield (300 U l(-1) h(-1)) co mpared to steady state results of a continuous stirred tank reactor.