| 摘要 |
PROBLEM TO BE SOLVED: To increase an acid concentration of a pickling liquid accommodated in pickling tanks other than the last pickling tank, to a desired value, while controlling an acid concentration of a pickling liquid from the last pickling tank to 12% or less. SOLUTION: This continuous pickling method comprises calculating predicted values for acid consumption of the pickling liquid due to pickling, which is accommodated each in the third tank 11c and in the last tank 11d of the continuous pickling apparatus 10, with a pickling-line control device 24; determining each supplying amount of the acid solution to the third tank 11c and the last tank 11d on the basis of the predicted values by the calculation; supplying the acid solution from an acid solution supplying system 12; continuously measuring acid concentrations of the pickling liquids accommodated in the third tank 11c and the last tank 11d, to which the acid solution has been supplied, with continuous acid-concentration measuring devices 13c and 13d respectively; and supplying the acid solution into the third tank 11c and the last tank 11d from the acid solution supplying system 12, on the basis of continuous measured values for the acid concentrations, so that the acid concentration of the pickling liquids accommodated each in the third tank 11c and the last tank 11d can correspond to the desired values. |
