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In order to eliminate sunlight in glasshouses and reduce construction costs for commercialization of microalgae culture with CO2fixation, a wind-resistant column photobioreactor was developed using computational fluid dynamics to tolerate 40 m/s typhoons for outdoor microalgae growth. As the height decreased and the thickness increased, the deformation and stress of the reactor decreased under wind pressure. As the center distance of the pipe row increased, the deformation and stress decreased, while the space utilization also decreased. Moreover, with the increase in the longitudinal distance of the double pipe rows (DPR), the wind flow disturbance decreased. However, the effect of the lateral distance change was less. The optimized structure of DPR with a single pipe height of 3.9 m, and a thickness of 3 mm gave a deformation of 3.18 cm and Von-Mises stress of 7.27 MPa. The consumption of materials for ring fixation with safe support spacing of one and two pipes decreased by 49 and 71%, respectively, compared to that of bottom fixation..

High microalgal growth rates depend on appropriate solution mixing, and therefore, mass transfer can be achieved by installing baffle structures into photobioreactor (PBR) systems. In this study, butterfly-shaped baffles were installed in a double-column photobioreactor (DC-PBR) to decrease the mixing time, increase the mass transfer coefficient, and promote the growth rate of Arthrospira platensis. The mixing time was reduced by 20%, increasing the baffle size and the angle between wings, resulting in the mass transfer coefficient being simultaneously enhanced by 32%. The vertical flow vortices generated by the butterfly baffles strengthened the light/dark cycle between the inner and outer columns in DC-PBRs, which improved the chlorophyll-a content by 19%, photochemical efficiency and electron transfer rate by 20% during photosynthesis. The biomass growth rate of A. platensiswas increased by 33% with the addition of a butterfly baffle to the PBR, while the helix pitch and trichome length were enlarged by 15–16%.