| 摘要 |
The purpose of the present invention is to provide a flue gas treatment device and method capable of preventing wear of a pipe group in a gas-gas heater (GGH) while preventing increased size of equipment such as electrostatic precipitators and silos occurring in methods of estimating SO3 concentration from measured values of SO2 concentration in an exhaust gas. In this flue gas treatment technique, the SO3 concentration in a flue gas containing at least SO2 and SO3 is detected with an SO3 concentration meter, a powder is supplied into the flue gas for which the SO3 concentration was detected, heat is recovered from the flue gas to which the powder was supplied, cooling said flue gas, and dust in the cooled flue gas is collected to absorb and remove, by an absorbent liquid, at least the SO2 in the flue gas from which the dust was collected, wherein, when the powder is supplied, the amount of powder supplied is controlled such that the mass ratio of the total of the soot and dust concentration (A) and the powder concentration (P) in the flue gas over the SO3 concentration (S) {(A+P)/S} is 2.0 or greater. |
