Outdoor open pond batch production of green microalga Botryococcus braunii for high hydrocarbon production: enhanced production with salinity

Abstract

the aim of this work was to enhance the biodiesel quality and hydrocarbon content of green microalga B. braunii strain KMITL 2 cultivated outdoor under several salinity conditions in a batch production. the enhancement would be such that the microalgal biodiesel qualities met or exceeded the current standard so that it would be a good raw material for biodiesel production. the microalga production was in 300 L open oval ponds, among various salinity levels tested (0-20 ppt), 5 ppt was the best for hydrocarbon production, yielding 54.2 ± 0.9% hydrocarbon content and 5.1 ± 0.4 g L −1 biomass. As the microalga production was scaled up by cultivation in 3,675 L open raceway pond under the 5 ppt condition, the microalga yielded a bit higher hydrocarbon content (58.8 ± 2.9%) but much lower biomass (2.5 ± 0.5 g L −1 ). The production in both oval and raceway ponds yielded a nearly identical biodiesel property (61.06-67.42 cetane number) which exceeded the value specified in international standards. Therefore, it was concluded that B. braunii strain KMITL 2 can be batch cultivated in an open pond at optimum salinity to yield sufficient hydrocarbon and biomass for biodiesel production.

Transformation technologies for CO2 utilisation: Current status, challenges and future prospects

“…Overall, microalgae growth increases with the light intensity till a certain intensity threshold above which the productivity decreases due to photoinhibition [63][64][65]. The technical challenge is to evaluate the effect of light intensity on microalgae growth and lipid content (source of biofuel synthesis from algae) on a specie-by-specie basis.…”