Method for controlling crevice chemistry on the secondary side of a pressurized water reactor steam generator

Abstract

A method for detecting pH imbalances and/or achieving pH balance in crevices of a pressurized water reactor steam generator. The method comprises obtaining hideout return concentrations of sodium, chloride, calcium and sulfate ions, and silica from the water in the secondary side of the steam generator, the concentrations being expressed as moles per kilogram of water, and determining whether the following conditions exist: eq (anions)<eq (cations), and (a) [Na.sup.+ ]<[Cl.sup.- ]+2[SO.sub.4.sup.2- ] (b) the crevice pH being balanced when all the conditions of the determining step are satisfied. The method of the invention preferably further includes determining whether the following conditions also exist: [Cl.sup.- ]<[Na.sup.+ ] (c) [SiO.sub.2 ]>[Ca.sup.2+ ]+[Mg.sup.2+ ] (d) [Na.sup.+ ]/[Cl.sup.- ]<1.9. (e) If and when the above conditions are met, it can be expected that crevice pH will be balanced at a generally neutral level.

Dependencies are inferred from the claim text.