Spirulina platensis Culture with Flue Gas Feeding as a Cyanobacteria‐Based Carbon Sequestration Option

The scientific community is currently examining potential approaches in order to reduce the anthropical contributions to global warming. One approach is carbon capture and its storage, i.e., capturing CO₂ at its source and storing it indefinitely to avoid its release into the atmosphere. Conversion of CO₂ by microalgae or cyanobacteria is a sequestration option. Here, the application of an air‐lift reactor to flue gas treatment using cyanobacteria for the absorption of CO₂ was investigated, with the simultaneous abatement of NO_x. A Spirulina platensis culture was fed with CO₂ and NO_x, simulating a flue gas. The preliminary test yielded positive indications on the process feasibility, both in terms of cell productivity (86.8 mg L^–1d^–1) and CO₂ abatement (229 mg d^–1). Opportune dosages of flue gas used in fed‐batch test achieved a high abatement of CO₂ (407 mg d^–1), 90.0 % removal of NO_x, and a biomass production of 188.7 mg L^–1d^–1.