The synergetic removal of multiple pollutants in flue gas was investigated in a gas-liquid flow pattern-controlling (FPC) column coupled with ultrasonic wave (UW). A pilot-scale experimental setup with a gas flow rate of up to similar to 432 m(3)/h was developed for the removal of SO2, SO3, and fly ash. A comparative study was conducted between the FPC column and the traditional open spraying (OS) column to show the superiority of the FPC column. In general, the synergetic purification performance was significantly improved by using the FPC and UW. The SO3 aerosol removal efficiency in the FPC column was about 9.9% higher than that in the OS column. At a liquid-to-gas ratio (L/G) of 10 L/Nm(3), the efficiency of SO2, SO3, and fly ash particle removal increased by 8.7, 5.3, and 6.6% with the introduction of UW, respectively. This enhancement effect of the UW became greater with increasing the L/G due to the increased liquid holdup. Furthermore, the energy consumption analysis was applied based on an actual WFGD system of a 660 MW power plant to estimate the energy penalty of the FPC and FPC-UW columns.