2.1 Mist bioreactor design and construction
The experimental setup (mist generator and accessories) were depicted in figure 1. Sterilized air generation system contains an oil-free compressor, pressure regulator, solenoid valve, needle valve, rotameter, and air Sparger.
The air is produced by an oil-free compressor (Fini - Italia) and passes through the pressure regulator (Festo - Germany), the needle valve and the rotameter (Dywer - USA) to have an adjusted flow rate of 25 lit/min at a pressure of 2 bar. The air introduced into the mist chamber via an air Sparger. The air sparger contains 4 pores with a diameter of 1 mm. The pores were in front of the media surface so the airflow was blown to the surface that sweeps up all mist. The mist was generated by an ultrasonic transducer (Ceramic ultrasonic piezoelectric with 1.12 MHz frequency and 20 mm Diameter) that was attached centrally at the bottom of the mist chamber base (Fig. 1). The mist droplets are separated from the medium surface.