Effect of heat stable salts on MDEA solution corrosivity. Part 2. P.C. Rooney, M.S. DuPart and T.R. Bacon. Hydrocarbon Processing, April 1997, 76(4), 65--71.
The effect of various heat stable salts on the corrosivity of methyldiethanolamine (MDEA) solutions is described. Corrosion coupons of carbon steel and stainless steel are exposed at 180 and 250
C. The experimental procedure is described and illustrated and an equation is given for calculating the corrosion rate. Effects of oxalates, sulphates, formates, acetates and thiosulphates are reported and maximum concentrations of these salts are recommended. Results are influenced by pH. Oxalic acid significantly increases corrosivity due to chelation of the oxalate with iron. Corrosive effects in the presence of succinates, malonates, glycolates, SO2 and ammonia are described. Caustic neutralization guidelines for MDEA heat stable salts are given. 8 refs.