Patent ID: 8501475

Claim:
A method for removing contaminants from a liquid culture, comprising: coupling an inlet tube to a vessel containing a liquid culture, the liquid culture comprising a growth medium, an initial live population of at least one of microalgae and cyanobacteria less than 20 microns in size, and contaminants; receiving the liquid culture from the vessel into the inlet tube; transferring the liquid culture from the inlet tube to a gas injector using a preselected liquid flow rate; injecting a gas into the liquid culture using a preselected gas flow rate to mix the gas with the liquid culture and produce a gas and liquid culture mixture; receiving the gas and liquid culture mixture into a first end of a substantially vertical chamber; propelling the gas and liquid culture mixture from the first end of the vertical chamber to a second end of the vertical chamber; generating a foam comprising at least some contaminants as the gas and liquid culture mixture travels from the first end to the second end of the vertical chamber; collecting the foam comprising at least some contaminants continuously in a collection container disposed at the second end of the vertical chamber; and returning the remaining gas and liquid culture mixture to the vessel, wherein the remaining gas and liquid culture mixture comprises less contaminants than the liquid culture from the vessel and at least a portion of the initial live population of at least one of the microalgae and the cyanobacteria.