steel digester systems is being encountered. Many mills have had severe corrosion in the flash tanks, in particular, the first (#1) flash tank. The work described in this report was aimed at characterizing the
corrosion. Coupons of carbon steel, several stainless steels and titanium were exposed at two mills. At mill A, identical sets of coupons were exposed in the #1 and #2 flash tank. At mill B, three identical sets of
coupons were placed in flash tank #1. The results of the exposures showed that both carbon steel and titanium suffered high rates of general corrosion, while the stainless steels suffered varying degrees of
localized attack. The ranking of the resistance of corrosion in the flash tank was the same ranking as would be expected in a reducing acid environment. In the light of the coupon results, organic acids is concluded to be the most likely cause of corrosion of the flash tanks.
Keywords: corrosion, corrosion tests, flash tanks, carbon steel, stainless steel, titanium, organic acids, inorganic acids