the semi-continuous technique is used for
pilot scale study by partial periodic harvesting. During semi-continuous
cultivation the culture was initially grown under batch
mode, once the dry biomass reached 1 g/L, 40% of algae culture
was harvested and this was repeated for every three days interval.
This experiment was carried out for more than three weeks and the
maximum algal growth was achieved during logarithmic phase.
The pH of the pond culture was maintained between 7.5 to 8.5,
when the pH rises beyond the level; CO2 gas was pumped into
the pond to maintain the pH. The biomass was harvested seven
times during semi-continuous mode, and each harvest the dry biomass
productivity was estimated and recorded up to 33.8 g m2 -
day1 (