Hydrogen Permeation Estimated by HMT in Carbon Steel Exposed to Gaseous Hydrogen

Abstract

Hydrogen permeation behavior in carbon steel exposed to gaseous hydrogen was visualized using a hydrogen microprint technique (HMT). Effects of hydrogen gas pressure and charging time on the hydrogen permeation were particularly examined. The amount of permeated hydrogen was dependent on the charging time during the exposure to gaseous hydrogen. It was found that silver particles, which represented the evolution site of hydrogen atoms, were distributed almost uniformly in the matrix after hydrogen gas charging. These particles were arranged at the periphery of the second phase particles such as Al 2 O 3 . Area density of the silver particles clearly increased when the time for hydrogen gas charging was increased. Preferential accumulation of silver particles around Al 2 O 3 particles was clearly identified; however, no silver particles were observed directly on the Al 2 O 3 particles. This indicated that hydrogen atoms were diffused not through the inside of the second phase particles but through the interface between the second phase particles and the matrix phase.

Full-Scale Hydrogen Mitigation Installation and Testing at Nevada Solar One

“…Dissolved hydrogen concentrations would increase to high pressures except for permeation of hydrogen through the plant piping and process equipment walls that causes dissolved hydrogen to reach a quasi steady-state concentration. Piping and process equipment are composed of carbon steel, which is permeable to hydrogen [4,5]. Its permeability also has an Arrhenius temperature dependence.…”

Acciona Power Plant Hydrogen Mitigation Project

“…Dissolved hydrogen concentrations would continue to increase except that permeation of hydrogen through the plant piping and process equipment walls causes dissolved hydrogen to reach a steady-state concentration. Piping and process equipment are composed of carbon steel, which is quite permeable to hydrogen [13,14], and its permeability also has an Arrhenius temperature dependence. The steady-state dissolved hydrogen concentration is the value at which the plant-wide hydrogen generation rate equals the plant-wide hydrogen permeation rate out of the plant via piping and process equipment walls.…”

“…is the partial pressure of gas-phase hydrogen in the tank. is the permeation coefficient for hydrogen for the expansion tank wall material, which is carbon steel [13,34]. is a function of temperature and is defined as:…”