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High-rate algal ponds have the potential to produce 59T of dry biomass ha⁻¹year⁻¹ based on the specific productivity of 20gm⁻²day⁻¹. Atmospheric air provides only 5% of the CO₂ to the pond surface required for photosynthesis. Hence, CO₂ is usually provided via bubbling of concentrated CO₂-air mixture into the algae ponds. This process is, however, not significantly effective in terms of mass transfer. Use of bubble column to increase the interfacial area of contact available for gas exchange is proposed as an efficient alternative. A carbonation column (CC) was modeled and designed to measure CO₂ absorptivity in-pond water at various pH regimes. The CC performed at 83% CO₂ transfer efficiency. An air-to-pond mass transport coefficient of 0.0037mmin⁻¹ was derived. The proposed device can be used with any exhaust gas stream with higher concentrations of CO₂ in conjunction with raceways for …