2.2. Operation of photobioreactor
The photobioreactor (PBR) used to cultivate the A. platensis was
a 1-L glass vessel (15.5 cm in length and 9.5 cm in diameter)
equipped with an external light source (14 W TL5 tungsten fila-
ment lamps, Philips Co., Taipei, Taiwan) mounted on both sides
of the PBR. The microalga was pre-cultured and inoculated into
the PBR with an inoculums size of 0.08–0.24 g/L. The medium used
for strain culture in the PBR was Zarrouk medium. The PBR were
operated at 28 C, pH 9.0, and an agitation rate of 400 rpm under
a light intensity of approximately 75–450 lmol/m2
/s. Serving as
the sole carbon source, 2.5% CO2 with 0.2 vvm was fed into the
microalgal culture continuously during cultivation. Liquid samples
were collected from the culture broth at set time intervals to deter-
mine the cell concentration, pH, C-PC content and residual nitrate
concentration