Mr. Jean-Marc Sluyters from Gemaco S.A. has presented a Technical Paper and presentation during the Nitrogen+Syngas 2013 about using corrosion resistant stainless steels to improve reliability in Urea & Nitric Acid Plants.
“Urea and Nitric Acid Plants are prone to various corrosion phenomena depending on the process, the concentration, the temperature, the composition of the gas itself, etc.
We should consider that the role of impurities and process variables such as oxidizing impurities in nitric media are generally as important as the nominal composition. In all cases the chlorides or halogen contents are also disturbing. Therefore special austenitic stainless steels with specific requirements have been developed. Experience has proven that applying inferior materials was an attractive solution, standard, easier to find, cheaper, but not reliable and leading sometimes to safety risks and/or unplanned shut downs. If most of the problems can be anticipated by regular maintenance, some issues can occur unexpectedly. Such situations lead to an indefinite time during which the plant is out of operation, not producing but also sometimes impacting the downstream industries.”
The full article can be found HERE