Process for microalgae conditioning and concentration
Conditioning and concentration of microalgae are accomplished by the process steps of grinding a dilute aqueous dispersion of microalgae in the presence of grinding media and then applying adsorptive bubble separation. This process is amenable to the use of dilute feed microalgal dispersions such as are encountered in the production of algal biomass for biofuel applications.
1. A continuous process comprising:
a. providing a dispersion comprising a carrying liquid and Dunaliella microalgae cells;
b. passing the dispersion through a grinding mill wherein the Dunaliella microalgae cells are contacted with moving grinding media to disrupt the cell membrane of the Dunaliella microalgae cells and to form a conditioned slurry comprising hydrophobic Dunaliella microalgae bodies;
c. treating the conditioned slurry with an adsorptive bubble separation process to form a stream rich in Dunaliella microalgae bodies and a stream depleted in Dunaliella microalgae bodies.
2. The continuous process of claim 1 , wherein the Dunaliella microalgae cells comprise Dunaliella salina.
3. The continuous process of claim 1 , wherein the grinding mill comprises an agitated bead mill.
4. The continuous process of claim 1 , wherein the adsorptive bubble separation process comprises froth flotation.
5. The continuous process of claim 4 , the froth flotation is performed in a Jameson cell.