METHOD FOR CONTROLLING LIQUID LEVEL OF ABSORBING TOWER IN FLUE GAS DESULFURIZATION APPARATUS ACCORDING TO WET LIMESTONE/GYPSUM PROCESS

摘要

PURPOSE:To constantly control the concn. of CaCO3 in a washing solution even if the flow amount of flue gas is varied, by calculating the level set value of a washing solution as the function of the flow amount of flue gas and operating the regulation valve of the washing solution withdrawing piping from an absorbing tower by a level regulator. CONSTITUTION:Flue gas is introduced into an absorbing tower 3 from an exhaust gas inlet duct 1 and cooled at the inlet part of the absorbing tower 3 by a washing solution to remove dust in said flue gas and SOx in the flue gas is further absorbed by the washing solution in the main body part of the absorbing tower 3. The washing solution is supplied to the absorbing tower 3 by a pump 5 through recirculation piping 6 and a part thereof is discharged out of the system through piping 8. The gas flow amount detection signal from the flowmeter 11 arranged to the inlet duct 1 is inputted to a function generator 12 and the output signal thereof is inputted to a level detection regulator 9 as the level set value thereof. A regulation valve 10 is operated by the level detection regulator 9 so as to adjust the level of the washing solution to said set valve to regulate the withdrawal amount of the washing solution.