Effect of ejector operation on the oxygen transfer in a pilot jet loop reactor

Abstract

Jet loop reactors (JLRs) are an alternative reactor type for the intensification of aerobic bioprocesses which are normally carried out in stirred tank reactors (STR). A JLR is capable to generate the same oxygen transfer rate (OTR) at a higher efficiency compared to a STR. If the ejector nozzle of a JLR is used for headspace pressurization, the oxygen mass transfer can be increased even further. However, intensified mass transfer usually requires increased power inputs while mass transfer efficiencies are decreased. In this respect, the energy efficiency of a JLR designed for intensification of an industrial bioprocess was evaluated. Compared to a STR, the JLR achieved a 70% higher mass transfer rate at identical power input. Based on the results obtained for mass transfer performance, an increase in aerobic biomass formation up to 100% can be expected for the JLR in comparison to the STR.