This paper discusses a successful experience in solving corrosion problems in the overhead system of a sour water stripper. In general, corrosion in this area is manageable unless the water discharged from a fluid catalytic cracking unit, which often contains a significant amount of cyanides, is processed. However, severe corrosion caused by condensed ammonium bisulfide (NH4HS) occurred in sour water stripper overhead condenser tubes fabricated from Type 316L stainless steel (SS). Higher corrosion rates were observed on the upper side of a tubes exposed to the vapor phase. By performing the process analyses using the electrolyte process simulation, the most influential variables determining the localized concentration of NH4HS and resultant corrosion rate were detected. The countermeasures to avoid the localized accumulation of corrosives successfully reduced the corrosion rate to a negligible level.

Subject
Water, Materials, Modeling, Hydrogen concentration, Corrosion rate, Tubes, Reflux, Vapors, Sour water, Condensers, Cooling systems, Salt concentration, Electrolytes
Keywords:
ammonium bisulfide, sour water stripper, air cooler, electrolyte process simulation, process analyses
© 2005 Association for Materials Protection and Performance (AMPP). All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise) without the prior written permission of AMPP. Positions and opinions advanced in this work are those of the author(s) and not necessarily those of AMPP. Responsibility for the content of the work lies solely with the author(s).
2005
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.