CO2 absorption rate in an algal culture: Effect of pH

Abstract

AbstractIn a CO2‐limited algal culture, grown in a tubular loop photobioreactor, the maximum rate of CO2 absorption increased about 1.5‐fold when the culture pH value was increased from 6.5 to 7.5 with a fixed initial PCO2. The mean volumetric CO2 transfer coefficient (KLa) increased about 1.8‐fold. The bicarbonate ion concentration would be increased 10‐fold by the pH increase. The effect of pH on the absorption rate is attributed to changes in either the CO2 diffusivity, the gas bubble size, or the CO2 reaction kinetics at the gas/liquid boundary.