Corrosion in steam generation

Savlc, D. Oplk, I. Fouling and Corrosion In Steam Generators, Beograd 1980. 

Theus, G. J. and David, D. L., Corrosion in Steam Generating Systems, Corrosion in Power Generating Equipment, M. O. Speidel and A. Atreus, Eds., Plenum Press. 

Burgmayer, P. R. Cotton, I. J. Knowles, G. Oxygen Scavenging and Passivation in Steam Generating Systems Fiction, Folklore and Fact. Betz/NACE Annual Conference and Corrosion Show, USA, 1992. 

There are few published electrochemical studies of supercritical water (temperatures and pressures above 374 and 218 atm). Some of the data pertain to the power generation industry for example, a 1975 report summarizes some industrial experience with corrosion of steam generator tubing in pressurized water reactors (4). Most of the other literature references concern... 

Weeks, J. R. "Corrosion of Steam Generator Tubing in Operating Pressurized Water reactors". In Corrosion Problems In Energy Conversion and Generation Electrochem. Scl., 1975... 

Bryers, R.W. Walchuk, O.R., "The Influence of Pyrites on Slagging in Steam Generators", International VGB Conference on Slagging, Fouling and Corrosion on Thermal Power Plants, VGB Technical Association of Large Power Plant Operators, Essen, West Germany, February 1984. 

Ion chromatography is frequently used to determine anions and cations at very low concentration levels, often in the low xg/L (ppb) range. In the electric power industry the water used in steam generators must be almost free of Na", Cl" and other ions to avoid stress corrosion cracking. The ionic content of ultrapure water used in the electronics industry must be kept to extremely low levels. Semiconductor chip manufacturers require clean-rooms with utility impurities of no more than 1 ppb for 0.35 pm devices [1]. 

Alkaminox . [Rhone-Poulenc Surf.] Ethoxylated fatty acid amine textile scourii dyeing assistant, softeno , antistatic agent used as corrosion inhibits in steam generating and circulating systems coemulsifio . 

Of course, the actual application of pertechnetate ions to corrosion inhibition of iron and carbon steels will obviously be a great problem because of the radioactivity of Tc, even in dilute solutions of TcO. A pertechnetate concentration of 5 10 M corresponds to a specific radioactivity of 84.15 pCi/l or 3.11 U/ Bq/1. Nevertheless, the corrosion inhibiting property of TcOj was proposed to be used in steam-generating nuclear reactors [42,43[-... 

Because of the complex and often corrosive environments in which the power plants operate, corrosion has been a serious problem. Corrosion continues to be a problem with electrical generators and turbines. Specifically, SCC in steam generators in PWR plants and boiler tube failures in fossil fuel plants continue to be problems. 

IAEA TECDOC-667 Coolant Technology of Water Cooled Reactors. Vol. 2, Corrosion in the Primary Coolant Systems of Water Cooled Reactors. Vienna, 1992, p. 65—68 Asay, R. H., Naudin, O., Thiry, M., Lantes, B., Gouillardou, G., Saurin, R, Weber, C. (a) Effect of surface treatments on radiation buildup in steam generators. Vol. 1. Manway seal plate tests in the Chinon B1 PWR. Report EPRI TR-100059, Vol. 1 (1991)... 

The objectives of corrosion testing and associated monitoring of chemical, stress, and thermodynamic conditions in steam generating cycles are ... 

FIG. 3—Three components of corrosion control in steam generating cycles. 

Corrosion control in steam-generating systems is by a combination of design, material selection, water treatment, and... 

On the other hand, the electrical conductivity information is essential for several practical applications of the hydro-thermal systems. It is well known, for instance, the use of electrical conductivity measurements on Une to prevent corrosion problems in steam generators and other applications of the steam/water cycle. Tracer diffusion coefficients of electrolytes can be calculated from limiting electrical conductivity and used to predict mass transfer in many geochemical processes and hydrothermal reactions. 

A review of the various corrosion issues was presented by Leedy. The discussion included the free corrosion rates on various metals (controlled successfully) as well as the galvanic corrosion of weldments. The author concluded that the attack on the weldments would not be excessive in the geometries expected in steam generators (SGs). Processes based on the EPRI/SGOG development effort have been used to clean SGs at Three-Mile Island-1, Byron 1, Sequoya 1 and 2, Surrey 1 and 2, Callaway and Kori (Korea), Duke Oconee, and Ontario Hydro Pickering. 

Although nickel alloys on the whole offer a better resistance to stress corrosion cracking over the steels, their application in high temperature chloride or alkaline environment and hydrogen sulfide environment may put them to the risk of stress corrosion cracking. Cases of SCC have been observed in high temperature pressurized water in steam generating turbines. Incoloy 800... 

Corrosion damage in steam generator tubes. The history of corrosion damage in steam generator tubes has been described in detail elsewhere. The problems have mainly been related to Alloy 600 (a Ni, Cr, Fe alloy) and have contributed to seven steam generator tube ruptures, numerous forced reactor shutdowns, extensive repair and maintenance work, steam generator replacements, and also radiation exposure of plant personnel. A brief summary follows. 

In steam generation, D.O. is one of the important factors causing corrosion of the boiler material. From boiler-feed water, D.O. is removed by physical and chemicals means. Measurement of D.O. is necessary to control tiiese processes. 

R.W. Staehle, J.A. Gorman, K.D. Stavropoulos, and C.S. Welty, Application of statistical distributions to characterizing and predicting corrosion of tubing in steam generators of pressurized water reactors, in Proceedings of Life Prediction of Corrodible Structures, Ed. R. N. Parkins, NACE International, Houston, TX, 1994, pp. 1374-1439. 

Uses Thickener, foam stabilizer, and emulsifier for formulated detergents and cosmetics corrosion inhibitor in steam generating and circulating systems Properties Tan paste sol. in aromatic solv., perchloroethylene disp. in water pH 10.0-11.5 (5%DW)... 

Uses Surfactant, emulsifer in cosmetics cleansing agent, skin protectant in detergents, cleaning agents corrosion inhibitor in steam generating and circulating systems foam stabilizer, thickener in shampoos, liq. dishwash and bubble bath formulations... 

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