Large-Scale Cultivation of for Biological CO Mitigation in Open Raceway Ponds Using Purified CO From a Coal Chemical Flue Gas.

In order to select excellent strains with high CO fixation capability on a large scale, nine species were cultivated in columnar photobioreactors with the addition of 10% CO. The two species selected (208 and 220) were optimized for pH value, total dissolved inorganic carbon (DIC), and phosphorus content with intermittent CO addition in 4 m indoor raceway ponds. On the basis of biomass accumulation and CO fixation rate in the present study, the optimum pH, DIC, and phosphate concentration were 9.5, 0.1 mol L, and 200 mg L for both strains, respectively. Lastly, the two strains selected were semi-continuously cultivated successfully for CO mitigation in 605 m raceway ponds aerated with food-grade CO purified from a coal chemical flue gas on a large scale. The daily average biomass dry weight of the two stains reached up to 18.7 and 13.2 g m d, respectively, suggesting the two strains can be utilized for mass production.