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Medvedeva, M. L.; Gur’yanov, V. V.

doi:10.1023/a:1015677624002

Cited by 5 publications

(3 citation statements)

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“…[1] H2S is one of the most dangerous factors causing metal corrosion in acidic oil and gas environments, and electrochemical corrosion will occur on the surface of the pipeline used. [2] In recent years, many researchers have conducted extensive research on the local corrosion and stress corrosion cracking (SCC) mechanism of stainless steel in H2S medium. The research was focused on the structure, properties, formation process and external factors of corrosion products in saturated H2S systems.…”

Section: Introduction Introduction Introduction Introductionmentioning

confidence: 99%

The Effect of Liquid Nitriding on the Corrosion Resistance of AISI 304 Austenitic Stainless Steel in H2S Environments

Wang

Jin³

et al. 2018

Metall Mater Trans A

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AISI 304 austenitic stainless steel was low-temperature liquid nitrided in a molten salt bath at 703 K for 8 h, which produced a 3-layered structure consisting of a top oxide layer, an intermediate nitrogen-rich layer and a bottom carbon-rich layer. The effect of nitriding on its corrosion resistance was investigated in a H2S environment. The corrosion rate of the untreated sample is about 3.3 times that of the nitrided sample after H2S corrosion. Corrosion pits can be clearly observed on the surface of the untreated sample, while the nitrided sample surface remained relatively intact. Both the oxide layer and the nitrogen-rich layer can help reduce the hydrogen permeation, which is beneficial for combating hydrogen embrittlement. The corrosion products mainly consisted of oxides, hydroxides, and sulfates. The nitrided layers can serve as a barrier to corrosion, thus preventing the corrosion of the substrate material. Active nitrogen in the nitrided layer reacts with H ions to form NH4 + , which effectively prevents further acidification of the local area and inhibits the occurrence of pitting corrosion and the dissolution rate of the metal in the etching hole, thus improving the local corrosion resistance of the stainless steel.

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Section: Introduction Introduction Introduction Introductionmentioning

confidence: 99%

The Effect of Liquid Nitriding on the Corrosion Resistance of AISI 304 Austenitic Stainless Steel in H2S Environments

Wang

Jin³

et al. 2018

Metall Mater Trans A

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“…Deep pitting attacked the inlet unions for a solution of the absorbent supplied from the reboiler's desorber ( T = 127 ° C, p = 1.4 atm). The general corrosion rate of the lower part of the absorber ( T = 110 ° C, p = 65 atm) and the outlet union for a saturated solution of the absorbent itself was 1.0 mm/yr [1,2]. Separators corroded so strongly that were replaced.…”

mentioning

confidence: 99%

“…At plants under consideration, corrosion cracking was only slight or was not detected at all, because all the casing equipment manufactured under industrial conditions is thermally treated according to stringent relevant regulations [1,2]. Surfacing materials corresponding in chemical composition to the nickel-based powders most commonly used for repair are usually highly resistant to corrosion cracking in both alkali solutions and moist hydrogen sulfide.…”

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confidence: 99%

On Unacceptable Use of Austenitic Sleeves and Surfacing Alloys for Repair of Carbon-Steel Equipment

2005

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Almost all gas-treating plants for removal of acidic impurities in Russian oil-and gas refineries have been operated for a period longer than their design service life. Their working media simultaneously contain passivators (30 to 40% solutions of alkanolamines) and activators (H 2 S up to 0.44 mol/mol of the absorbent and CO 2 up to 0.2 mol/mol of the absorbent). Carbon-steel equipment of such plants is actively attacked by pitting. For instance, during those periods of operation when a new type of the absorbent was put into service, pit growth rate on gas-scrubbing plants for removal of acidic impurities at the Astrakhan gas refinery sometimes exceeded 1 mm/yr. Pits were especially deep (sometimes as deep as the rejection line) in high-pressure separators near the inlet unions for a saturated solution of the absorbent; the unions themselves broke down as well ( T = 93 ° C, p = 17 atm). Deep pitting attacked the inlet unions for a solution of the absorbent supplied from the reboiler's desorber ( T = 127 ° C, p = 1.4 atm). The general corrosion rate of the lower part of the absorber ( T = 110 ° C, p = 65 atm) and the outlet union for a saturated solution of the absorbent itself was 1.0 mm/yr [1,2]. Separators corroded so strongly that were replaced. However, replacement of such large apparatuses as an absorber or a desorber is too complicated and expensive. In addition, the main part of their casings did not corrode significantly. Corrosion attacked only their parts in contact with a saturated solution of the absorbent (lower bottom and especially lower union).In similar cases, plant workers often use such an unauthorized method for unions repair as welding of a 12ï18ç10í steel sleeves from inside. As for the bottom, the corroded area was decided to undergo overlaing welding with a corrosion-resistant austenitic nickel alloy. Such surfacing materials are widely used to restore the damaged surface. The technology of their application is well developed. They are highly adhesive and durable. It is believed that since a damaged area that needs overlaying is substantially thinner than the adjacent intact area, the non-repaired surface will not be attacked by contact corrosion.At the same time, some anxiety precludes a specialist to approve the repair methods proposed by representatives of the plants without respective investigations.(1) Main working media of gas-scrubbing plants for removal of acidic impurities can cause not only pitting but also corrosion cracking. At plants under consideration, corrosion cracking was only slight or was not detected at all, because all the casing equipment manufactured under industrial conditions is thermally treated according to stringent relevant regulations [1, 2]. Surfacing materials corresponding in chemical composition to the nickel-based powders most commonly used for repair are usually highly resistant to corrosion cracking in both alkali solutions and moist hydrogen sulfide. However, the behavior of thus surfaced carbon steel is unpredictable.(2) The surface state of the ove...

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Preparation of stable superamphiphobic surfaces on X80 pipeline steel substrates

et al. 2016

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Untitled

Cited by 5 publications

References 1 publication

The Effect of Liquid Nitriding on the Corrosion Resistance of AISI 304 Austenitic Stainless Steel in H2S Environments

The Effect of Liquid Nitriding on the Corrosion Resistance of AISI 304 Austenitic Stainless Steel in H2S Environments

On Unacceptable Use of Austenitic Sleeves and Surfacing Alloys for Repair of Carbon-Steel Equipment

Preparation of stable superamphiphobic surfaces on X80 pipeline steel substrates

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