Volumetric mass transfer coefficients, k(L)a, just as power input are considered as essential parameters for mechanically agitated gas-liquid contactors in relation to their optimization and design. The knowledge of power input is crucial for the prediction of other mass transfer characteristics. A power input correlation is created for the industrial design of the process with a non-coalescent batch that would be appropriate for a broad range of operational conditions. The recommended resulting correlation is able to predict the power input for impellers in industrial-scale design for a significant scope of operational conditions.