The synergetic particles collection in three different wet flue gas desulfurization towers: A pilot-scale experimental investigation

The synergetic removal of particulate matters (PM) in different wet flue gas desulfurization (WFGD) towers was investigated on a pilot-scale experimental setup with the gas flow up to 6372 m(3)/h. Three types of scrubbing tower, i.e. open scrubbing tower (OST), scrubbing tower with porous tray (TST), and scrubbing tower with a flow pattern control device (FST) were used in this study. The multiphase flow is a counter-current liquid-dispersed flow in OST, while it is an insufficient developed and fully developed bubble flow in TST and FST, respectively. The PM collection efficiency was significantly increased after adding internals (porous tray or flow pattern control device). The total collection efficiency for TST and FST was similar to 84.3% and similar to 87.2%, respectively, when using gypsum slurry as recycle liquid at a superficial gas velocity of 3 m/s and L/G = 10 L/m(3). Comparing to that of OST, the improvement of the efficiency was similar to 9.2% and similar to 13% for TST and FST, respectively. Interestingly, even though the pressure drop of FST is lower than that of TST, the particle removal efficiency of FST is the highest among three scrubbing towers, which means FST is much more cost-effective. The performance index (P1) is introduced in this study to evaluate the particle removal effect of different internals. The P1 for FST is approximately 4 times larger than that of TST at L/G = 10 L/m(3), indicating a much better effect of FST for WFGD, especially for low-load operation in power plant.