2. Gas-liquid transfer of CO2, chemical equilibria in the liquid phase, material balances

Modeling (enabling quantification and understanding) CO ₂ exchanges between the gas and liquid phases of a microalgae production unit where it is consumed by photosynthetic microorganisms requires the consideration of several phenomena. Indeed, before we can write material balances on CO ₂ (or any form of inorganic carbon), we need to be able to describe and formulate the gas-liquid equilibrium, the equilibria between the different forms of dissolved inorganic carbon (DIC) in the aqueous phase, as well as the term translating mass transfer between phases. We saw earlier that the preferential form of inorganic carbon entering cells by active transport to be metabolized by photosynthesis is the hydrogencarbonate ion