Mixing

To optimize the photosynthesis rate and gas solubility in the media, mixing is very impor­tant. Besides that, mixing is important for homogeneous distribution of cells, metabolites, and heat and to transfer gases across gas-liquid interfaces. Mixing can be done mechanically by paddlewheel in raceways (Figure 4.4) or by gas flow in bubble columns.

image22"FIGURE 4.4 Paddlewheel mixing of raceway ponds at Ouro Fino Agronegcicio (Brazil).