Effects of reduced sulfur on passive film properties of steam generator (SG) tubing: an overview

Abstract

Purpose Corrosion is considered as one of the issues that threaten the safe operation of steam generator (SG) tubing. Some sulfur-related specie can cause corrosion degradation of SG tubing. Sulfur-induced corrosion of SG alloys in high temperature and high-pressure water is one of the most complicated processes. The purpose of this study is to study the effect of reduced sulphur on passive film properties of steam generator (SG) tubing. Design/methodology/approach In this paper, the effects of reduced sulfur on passive film properties of SG tubing were reviewed from the aspects of thermodynamic calculations and experimental. Findings Thermodynamic calculations are mainly presented by E-pH diagrams, volt equivalent diagrams and species distribution curves. The stability of sulphur species highly depends on temperature, solution pH, and electrochemical potential. Experimental data indicated that reduced sulfur species can interact with the passive film, which led to changes in film thickness, film structure, semiconductivity and pitting growth rate. Originality/value The state-of-the-art discussed in this paper gives basis for resolving engineering problems regarding with sulfur-induced corrosion.

The high-temperature mechanical properties of HS110S steel and its corrosion behaviors in harsh downhole environment

“…The ratio in this work is about 147:1, thus it can be inferred that H 2 S controls the corrosion process (Rebak and Perez, 2017), the corrosion scales could be mainly FeS x . The corrosive gas is dissolved into the solution, the corrosive ions are generated, including HS − , S 2− , CO 3 2‐ and HCO 3 − ions (Xia and Luo, 2019; Zhang et al , 2015). The main cathode reaction is hydrogen evolution.…”

Comparison of the effect of water jet cavitation peening on stress corrosion cracking behavior of nickel-based alloy 600 and alloy 182 in high temperature water

“…SSRT tests were performed in a simulated primary PWR environment (Xia and Luo, 2018; Wang and Zhang, 2017). Dissolved oxygen (DO) in the inlet water was less than 5 ppb, which was continuously monitored by a METTLER DO sensor.…”

Review—Factors Influencing Sulfur Induced Corrosion on the Secondary Side in Pressurized Water Reactors (PWRs)

“…Film thickness.-Passive film thickness in SG tubing is mainly influenced by the exposure temperature, and increases as the temperature rises. 145 At room temperature, the passive film thickness is in the range of several nm, but the thickness can increase to hundreds of nm at 300 • C. 126 As the temperature in a PWR rises, anion vacancy generation rate increases at the metal/film interface, film dissolution increases at the film/solution interface, and the transport rates of oxygen vacancies and cation vacancies are enhanced. Anion and cation vacancies generation rate at the metal/film interface is faster than the film dissolution rate and as a result, film thickness increases.…”