Botryococcus braunii cells: Ultrasound-intensified outdoor cultivation integrated with in situ magnetic separation

Botryococcus braunii for biodiesel production

“…Since B. braunii grows in colonies, its harvesting is less challenging than for no-colony microalgae [84]. So far, laboratory scale flocculation [26,85] and in situ magnetic [31] harvesting have been tested for B. braunii cells rich in lipids. B. braunii (UTEX 572) cells had been harvested using various flocculation methods.…”

“…(iv) Is the Submersible aquatic algae cultivation technology [67] adaptable for the B. braunii strains? [21] and plastic bag [31] reactors, respectively. Also, the cultivation of suspended B. braunii (NIES 2199) cells in a submerged membrane photobioreactor using effluent off-gas (CO 2 ) from an aeration tank and nutrients from the treated sewage was modeled [78].…”

“…Capacities of 400-1000 L and 200 L for the panel and plastic bag reactors, respectively, have been used only for suspended cells while immobilized cells are still at the laboratory scale. Like open systems, all of these experiments were conducted using synthetic media with atmospheric CO 2 as an inorganic carbon source [31] and using fertilizers [21]. Immobilized biofilm cultivation gives much lower biomass productivity compared to open pond systems, but the highest one (5.5 g/(L day)) among closed systems.…”

Recent nanoparticle engineering advances in microalgal cultivation and harvesting processes of biodiesel production: A review

“…As a follow-up study, Wang et al (2014b) developed a continuous in situ magnetic separation system, reporting the high recovery efficiency of 90% for B. braunii at a flow rate of 100 mL/min. Biocompatible chitosan has been successfully utilized as an Fe 3 O 4 nanoparticle surface-functionalization material for betterthan 95%-efficient harvesting of Chlorella spp.…”

“…The particle cost necessary for harvesting algal biomass can be calculated to USD $1.0/kg algal cell, based on the assumption of a microalgae harvesting capacity of 115 kg cell/kg particle . Wang et al (2014b) estimated the overall costs of the magnetic harvesting system and CPAM-coated Fe 3 O 4 particles as USD $2.1/kg algal cell and USD $0.73/kg algal cell, respectively. The reported costs of engineered nanoparticles (USD $0.73-1.0/kg algal cell) are still significantly high considering the target price of diesel (<USD $2/kg) (Jones and Mayfield, 2012;Kim et al, 2013a).…”