SULFITE CONTROL TO REDUCE MERCURY RE-EMISSION

摘要

PROBLEM TO BE SOLVED: To provide a method for reducing mercury emission and/or re-emission in cleaned flue gas through control of sulfite concentration within a wet flue gas desulfurization (WFGD) system.SOLUTION: One method for reducing mercury emission and/or re-emission through control of sulfite concentration is to measure the sulfite concentration of aqueous alkaline slurry used in a WFGD system and compare the concentration to a predetermined sulfite concentration value. If the comparison reveals that the measured sulfite concentration is above the predetermined values, the amount of oxidation air supplied to the system is increased. If the comparison reveals that the measured sulfite concentration is below the predetermined values, the amount of oxidation air supplied to the system is decreased.