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Indexed by:期刊论文

Date of Publication:2018-04-01

Journal:JOURNAL OF APPLIED PHYCOLOGY

Included Journals:SCIE、Scopus

Volume:30

Issue:2

Page Number:875-885

ISSN No.:0921-8971

Key Words:Microalgae; Mixing; Photobioreactor; Wave energy; Bicarbonate

Abstract:This study aims to develop a low-cost microalgae culture system which uses a simple closed vessel as photobioreactor to save manufacturing cost, waves for mixing to save energy cost, and high concentration of bicarbonate for carbon supply to avoid the high cost of CO2 -bubbling pipeline construction on the ocean as well as to control pH by buffering the effect of bicarbonate/carbonate. To test this idea, the alkalihalophilic cyanobacterium Euhalothece sp. was cultured with 1.0 M NaHCO3 in small-scale floating photobioreactors (PBRs) on 10-cm-high artificial waves at first. The final biomass concentration was up to 0.91 and 1.47 g L-1 for indoor and outdoor cultures, respectively. However, the recorded dissolved oxygen (DO) was occasionally over-saturated (> 500% of air saturation), indicating mass transfer problem. k(L)a in these PBRs with different culture depth was measured then, and the results showed great variation, from 0.13 to 4.87 h(-1). At the scale of 1.0 m(2). this floating PBR was made with low-cost membrane and inflatable design. It was placed on the ocean surface and mixed with natural waves. Biomass concentration of 1.63 g L-1 and productivity of 8.27 g m(-2) day(-1) were obtained in this culture. With these results, the feasibility of a low-cost microalgae culture system was proven, which could systematically reduce the cost of photobioreactor manufacturing, operating, and maintenance.