To analyse the influence of a non-corrosive hydrocarbon liquid phase with respect to CO2-corrosion in pipe flow and increase the understanding of use of natural inhibitors in the hydrocarbon liquid phase, an experimental study of corrosion and water distribution on the pipe wall has been carried out.
The influence of acetate ion on the rate of corrosion of carbon steel (X65) in 3 % NaCl brine saturated with carbon dioxide has been investigated using voltammetry at a rotating disc electrode. The rate of corrosion can only be understood if it is recognised that the cathodic process in the steel corrosion is affected by acetic acid.
The NORSOK M-506 is an empirical model based on experiments undertaken in a single phase water flow loop. The data is from experiments with low content of iron ions in the water phase, and the model is thus regarded to give a fair representation of the maximum corrosion rate in a CO2 corrosion controlled system.
Intergranular cracking and faiulure of carbon steel piping and vessels of FCC Main Fraqctionator overhead systems in NH3-H2S-CO2- containing environments is attributed to carbonate stress corrosion cracking. From plant water sampling program, cracking is correlated with water chemistry, open circuit potential and pH.
In any operating facility, the integrity of flare or relief lines should always be closely maintained, as it is one of the most important safeguards during plant upsets or emergency conditions. The most common damage mechanism in acid flare lines is acid gas dew point corrosion”. Corrosion in such systems is often dependent on fluid stagnation, especially in the presence of acidic water, during idle conditions.
The intent of this paper is to shed light on the efforts done in a gas treatment facility to identify different root causes that impacted or accelerated Acid Gas Dew Point Corrosion. These included design deficiencies, equipment integrity, and process challenges. Moreover, the paper provides findings and recommendations to avoid the occurrence of similar events in acid flare lines.