To efficientize microalgal cultivation including culture medium replacement, a novel acoustic apparatus named resonant ultrasound field-incorporated dynamic photobioreactor system (RUFDPBS) consisting of four compartments of (1) cell separation unit (RUF chamber), (2) ultrasonic equipment, (3) new & used media storage unit, and (4) cell culture unit is developed.

The cell collection, used medium draining, and new medium supplement in RUFDPBS operation are achieved through a segmented process whereby all the cells could be repeatedly harvested prior to medium change that is particularly advantageous for long-term cell collection operation and therefore enables a higher cell collection rate of > 90% compared with a similar RUF-based collecting device “BioSep”.

The RUFDPBS can be applied to cultivation of different kinds of cells (animal/plant; suspension/adhesion), especially for the ones which are very sensitive to environmental change and thus need frequent renewal of culture medium. In addition, since the RUFDPBS may provide numbers of merits such as energy saving, cost-effective, continuous process, and easy-to-scale up, the developed RUFDPBS is highly applicable for use in industry.