Corrosion problems in sulfur producing North German sour gas wells prompted an investigation into the performance of low and high alloy materials in brine/H2S/ elemental sulfur systems and the applicability of inhibitors. Experimental results proved that not sulfanes (H2Sx) but elemental sulfur is the oxidant in the corrosion reaction. However, direct contact of elemental sulfur (liquid or solid) with the sulfide covered metal surface is essential. Under these conditions low alloy and duplex steels are attacked by sulfur/brine suspensions at 90-140°C under 25 bar H2S and 25 bar CO2 hot pressure at high corrosion rates (10-100 mm/a). The steel MW 2832 is much more resistant but still corrodes at a rate of approx. 0.7 mm/a. Inconel 600, Inconel 718 and Incoloy 800 H are less resistant than MW 2832 by a factor of 3-4. Complete resistance was found for Inconel 625, Hastelloy C 276, MW 2550 and Alloy 825. Commercial inhibitors were found to decrease the corrosion rate of low alloy and duplex steels below 0.1 mm/a even under the above-mentioned severe conditions.

Subject
Sulfur, Materials, Corrosion rate, Nickel based alloys, Steel coupons, Solubility, Liquids, Corrosion inhibitors, Steel, Brines, Elemental sulfur, Corrosion coupons, Low alloy steel
© 1989 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).
1989
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.