CONTROLLING DEVICE FOR WET FLUE-GAS DESULFURIZATION

摘要

PURPOSE:To perform efficient desulfurization by calculating the flow rate setting signal of absorbent slurry for neutralizing acid from both acid gas concn. set by carbon species and flow rate of exhaust gas and adding it to the flow rate setting signal of absorbent slurry computed from SOX concn. CONSTITUTION:A desulfurization rate signal 26 is calculated via a substracter 24 and a divider 25 from the detection signal 22 of SO2 concn. in an outlet and the detection signal 23 of SO2 concn. in an inlet, and the total amount signal 31 of SO2 is calculated from both the flow rate signal 29 of dry-base exhaust gas which is obtained by correcting water content from the flow rate detection signal 27 of exhaust gas and the signal 23 and multiplied by the signal 26 and the flow rate setting signal 37 of absorbent slurry of an SO2 side is calculated via a function generator 34 and a multiplier 35. Further the flow rate setting signal 44 of absorbent slurry for neutralizing acid gas is calculated from both the signal 42 of acid gas concn. set by carbon species and the signal 29, and added to the signal 37 to obtain the flow rate setting signal 46 of absorbent slurry and an absorbent slurry control valve 15 is opened and closed by a deviation signal 40.