Harvesting Chlorella vulgaris by electro-flotation with stainless steel cathode and non-sacrificial anode.

[Display omitted] • Over 90% harvesting efficiency achieved using non-sacrificial anode. • Extracellular polymeric substance is the main reason keeping bubbles from bursting. • Hydrogen bubbles' size increased when the diameter of the cathode wire increased. As a promising method for efficiently harvesting microalgae, electro-flotation's performance is related to various factors including electrode design and process operating parameters. In this paper, bubble generation behavior on stainless-steel cathodes, with wire diameters of 0.8 mm, 0.2 mm and 0.05 mm, was studied. The results show that the bubble size increased with the increasing diameter of the electrode wire. Over 90 % harvesting efficiency was achieved using non-sacrificial anode. Extracellular polymeric substance is the main reason keeping bubbles from bursting. [ABSTRACT FROM AUTHOR]