SEED CRYSTAL SLURRY SUPPLY METHOD IN WASTE GAS DESULFURIZATION APPARATUS DUE TO WET LIME GYPSUM METHOD

摘要

PURPOSE:To prevent the scale adhesion in a washing apparatus, by constantly controlling the CaSO4-concn. in the washing liquid in a washing apparatus by measuring the flow amount of exhaust gas, the O2-concn. in the gas emitting from an oxidation apparatus, the flow amount of a washing liquid to the oxidation apparatus and the supply amount of a seed crystal slurry to the washing apparatus. CONSTITUTION:An exhaust gas flow amount G measured by a flow meter is inputted to an amplifier 25 and the O2-concn. in the gas emitting from an oxidation apparatus 5 measure by a densitometer 21 is inputted to a function generator 2. The withdrawing flow amount F of a wshing liquid to the oxidation apparatus 5 from a washing apparatus 3 and the flow amount F' of a seed crystal 3 from the oxidation apparatus 5 are inputted to a subtractor 33. The CaSO4-concn. of the washing liquid is calculated by the obtained values and the flow amount of the seed crystal slurry in an arranged pipe 6 is manipulated through a controller 29 by the CaSO4-concn. signal. If the set value of the controller 29 is set to a predetermined amount or more of a CaSO4-concn. generating no scale, scale is not generated under any operational condition.