The Bioreactor Tubes
The bioreactor tubes are made from PVC. Clear PVC 4.5" is used to contain the algae. At the top of the tube, there are two openings for air exchange.
In order that the algae not grow on the sides of the tube, a bio-airlift apparatus has been devised. The air inflow tube extends almost to the bottom of the PVC and air then bubbles up through the solution. This creates convection in the tube and prevents the algae from settling out.
The advantage of using PVC is that it is airtight and can easily be sterilized.