Hydrogen monitoring in geothermal plants and oil and gas refineries (NT TR 474)

Abstract

  The effluent hydrogen flux from a pressure vessel or pipe in hydrogenating service is a measure of the diffusible hydrogen concentration in the steel, and hence also of the possible hydrogenation reactions on the inside and the propensity to hydrogen induced disintegration of the steel wall. Effluent hydrogen can be collected from the external surface and quantified by several methods, one of which is based on the amporemetric principle (Devanathan/Stachurski principle). The work reported here validates the use of a sealed, dry contact amporemetric probe for hydrogen efflux measurements on vessels/pipes in ambient or elevated temperature services, and summarises the results and previous experience into a simple guideline. Attempts were made to validate the monitoring probe in field trials in Iceland.