The helical Flow promoter, a device that generates a circular motion in the gas liquid mixture circulating in a loop reactor, is presented. This device introduces an important change in the fluid dynamics of the reactor, which can be used to improve its performance, especially for heat and light transfer in photo-bioreactors. Data on the axial and circular velocity in a 60 liter reactor are presented, and compared with those of the ALR without HFP. Data on the improvement in fluidization capacity are presented.