In this study, a computational strategy is proposed for geometric design and prioritization of wave-plate mist eliminators by combining the Taguchi experimental design, CFD modelling, and Fuzzy Analytic Hierarchy Process (FAHP) approaches. The Taguchi approach is first used to identify a balanced set of geometric parameters and to generate 16 design cases depending on the chosen levels. A batch of CFD runs is then performed on these design cases to obtain the detailed multi-phase flow behaviour. Finally, the FAHP approach is employed in assisting the multi-criteria decision-making process of these design cases based on multi-run CFD results. To probe the separation mechanism, five design cases (named Cases 4, 8, 12, 15, and 16) with relatively high graded mean integration representation scores (GMIRs=0.0819, 0.0774, 0.0814, 0.0784, 0.0780) are systematically compared and analyzed regarding the profiles of static pressure, velocity, turbulent kinetic energy, etc. It indicates that Case 4, with the maximum level of bends (n = 4) and dimensionless width (W/S=0.55), as well as the minimum wavelength of a bend (λ = 1), can effectively reduce the power consumption while achieving a higher separation efficiency.