| 摘要 |
<p>PURPOSE:To control the circulation flow rate of an absorbing liquid with high accuracy and reduce power cost, by presuming the cause-effect relationships between the flow rate of an exhaust gas, SO2 concentrations before and after desulfurization, pH of the absorbing liquid and the circulation flow rate of the absorbing liquid and desulfurization ratio on an online basis, and setting the number of absorbing liquid circulating pumps to be operated according to the presumed condition. CONSTITUTION:A condition presuming calculator 11a calculates a necessary circulation flow rate of an absorbing liquid slurry from an exhaust gas flow rate signal Sf, a pH signal SpH, an inlet SO2 concentration signal Si and an output signal from a function generator 8. A signal obtained by processing a difference signal Sr indicating the difference between an actual desulfurization ratio Sa and a target value Ss by a recording controller 13a is added to an output signal from the calculator 11a, and the number of absorbing liquid circulating pumps to be operated is set by a setter 14 for the number. A calculated value Sca of desulfurization ratio is obtained from the signals Sf, SpH, Sdi and a slurry circulation flow rate signal Sc by a condition presuming calculator 11b, the difference between the calculated value Sca and an actually measured value Sa by a recording controller 13b, and coefficients used in the calculators 11a, 11b are corrected on an online basis, according to an output signal from the recording controller 13b.</p> |
