Current corrosion monitoring trends in the petrochemical industry

Abstract

Corrosion monitoring has traditionally been defined as the recording of historical events relating to materials degradation. This provided plant engineers and maintenance personnel with information only after damage has occurred and often integrated short term damage over the total exposure time. Modern petrochemical plants have, by nature of their size and subsequent operating costs, a definite need to predict and measure materials degradation due to corrosion during early stages and preferably on-line. An overview of traditional corrosion monitoring techniques such as corrosion coupon exposure and wall thickness measurements is provided. These techniques are now supplemented by modern electrochemical corrosion monitoring and measurement techniques. Modern corrosion monitoring techniques have found applications at Mossgas ranging from general corrosion in cooling water systems to severely localised stress corrosion cracking in gas systems. Three different case studies to illustrate this are presented.