Increasing Wet FGD SO_2 Removal Efficiency

摘要

New SO_2 emission regulations in the U.S. and EU require some utility and power producers to retrofit new flue gas desulfurization (FGD) units to existing plants. Amec Foster Wheeler's Dual Flow Tray Technology can provide a cost effective the scrubbing liquor neutralizes the liquid phase acids collected. Improving either process generally enhances SO_2 capture. The rate of SO_2 absorption into the absorber liquor is controlled by the mass transfer coefficient, the surface area available for mass transfer, and the difference between the SO_2 partial pressure in the flue gas and the vapor pressure of SO_2 at the gas/liquid interface. WFGD system designers can generally influence only the contact surface area and the dissolved alkalinity in the absorber slurry, which, in turn, determines interface vapor pressure. The surface area for mass transfer is determined by the selected liquid-togas ratio (L/G) in conjunction with the spray nozzle droplet size distribution.