How to Pressurize Autoclaves for Corrosion Testing Under Carbon Dioxide and Hydrogen Sulfide Pressure

Crolet, Jean Louis; Bonis, Michel

doi:10.5006/1.3280533

Cited by 14 publications

(12 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…where I k H 2 S = 230 mg/L/psia (0.1 mol/L/atm) for freshwater at 75°F (24°C) and 14.7 psia (101.3 kPa). 11,[37][38][39][40] Historically when qualifying carbon and low alloy steels for sour service at room temperature, stressed specimens were typically immersed in solutions containing up to 5 wt% NaCl and purged with either pure H 2 S at 1 atm or H 2 S in mixed gases to obtain P H 2 S less than 1 atm. [34][35] At the time, the effects of ionic strength were not considered in the analysis of the resulting data.…”

Section: Historical P H 2 S Paradigm-strict Henry's Law Approachmentioning

confidence: 99%

Optimizing Sour Gas Qualification Testing: Determination and Verification of H2S Solubility from H2S/N2 Gas Mixtures up to 20,000 psig at 70°F

2021

View full text Add to dashboard Cite

Traditionally, the H2S partial pressure (PH2S) of the gas/hydrocarbon phase has been used as the primary sour severity metric for material qualification and selection under ANSI/NACE MR0175/ISO 15156 guidelines. While the PH2S is appropriate for characterizing low total pressure systems, the strict, or ideal, Henry’s Law approach leads to over estimation of the dissolved H2S concentration (CH2S) for high-pressure, high-temperature (HPHT) wells by up to ~20 times at 70 °F (21 °C). Alternatively, the Ensemble Henry’s Law equation corrects for the non-ideal phase behavior of H2S at HPHT conditions and avoids over-estimation of CH2S. Given the industry’s reliance on using thermodynamic models to evaluate sour HPHT systems, an investigation was initiated to determine the accuracy of these model calculations. An empirical program was undertaken to verify CH2S predictions for the H2S-N2-H2O system. Multiple 2.7-L C-276 lined autoclaves were charged with a fixed inventory of H2S in N2 at multiple total pressure steps, with increasing N2 pressure, between 30 and 20,000 psig (3 and 1,380 bar) at 70 ± 5 °F (21 ± 3 °C). Per total pressure step, H2S levels in both the liquid and gas phases were measured using common H2S sampling techniques (H2S-specific colorimetric tubes and iodometric titration, respectively), following ANSI/NACE TM0177-2016 guidelines. The results were used to calculate total pressure corrected (apparent) H2S solubility coefficients (AkH2S). Very good agreement was observed between empirically and computationally derived AkH2S values. Key words: ANSI/NACE TM0177-2016, ANSI/NACE TM0284-2016, Sour testing, Ensemble Henry’s Law, Ionic-equation of state (EOS) frameworks, H2S solubility, Iodometric titration.

show abstract

Section: Historical P H 2 S Paradigm-strict Henry's Law Approachmentioning

confidence: 99%

Optimizing Sour Gas Qualification Testing: Determination and Verification of H2S Solubility from H2S/N2 Gas Mixtures up to 20,000 psig at 70°F

2021

View full text Add to dashboard Cite

show abstract

“…[16][17][18] After deoxygenation by bubbling N 2 for 12 h, the test autoclave was heated to the test temperature, and then charged with H 2 S to the target pressure. 19,20 All the test specimens, sized 30 mm620 mm63 mm, cut from the material were wet-ground with silicon carbide papers up to 1000 grit and then ultrasonically cleaned with alcohol for 5 min. After being weighed, they were immersed in the test solution.…”

Section: Test Proceduresmentioning

confidence: 99%

Corrosion behaviour of X52 pipeline steel in high H₂S concentration solutions at temperatures ranging from 25°C to 140°C

Liu

Wang

2013

Corrosion Engineering, Science and Technology

View full text Add to dashboard Cite

High temperature and high pressure immersion tests in an autoclave were employed to study the corrosion behaviour of X52 pipeline steel in aqueous solutions containing high concentrations of H 2 S. The corrosion products generated were characterised using scanning electron microscope, energy dispersive spectroscopy and X-ray diffraction. It was seen that at a constant H 2 S concentration of 22 g/l, the corrosion rate increased with increasing temperature up to 90uC, thereafter decreased at 120uC and slightly increased again at 140uC while the corrosion rate increased with H 2 S concentration at a temperature of 90uC. When the temperature and H 2 S concentration increased, the corrosion product converted from iron rich to sulphur rich products in the following sequence: mackinawiteRtroiliteRpyrrhotite, where the microstructure and stability of the corrosion products had an important effect on the corrosion rate. The corrosion film was formed through the combination of the outward diffusion of Fe 2z ions and the inward diffusion of H 2 S and HS 2 species.

show abstract

“…For example, when developing a new paint system, a 1000-hour test will significantly lengthen the development cycle. Autoclave test is one of the options for accelerating research, it combined effect of temperature, pressure and an aggressive environment Autoclave testing is used to assess the resistance of both metals and coatings [5,6]. There are standards and recommendations for conducting such tests, but as a rule, such documents describe general steps for conducting [7,8].…”

Section: Introductionmentioning

confidence: 99%

Investigation of factors influencing on the autoclave tests results of internal anticorrosive polymer coatings

Kovalev

Alekseeva

Shaposhnikov

et al. 2021

Proceedings of the 1st International Electronic Conference on Metallurgy and Metals

View full text Add to dashboard Cite

The use of polymer coatings is one of the most common methods of protecting metal structures from corrosion damage. For example, in the oil and gas industry, polymer coatings are used to protect the inner surfaces of oilfield pipelines. One of the open questions is predicting the life of the selected protective coating. Existing research methods are aimed at assessing the quality of coating application and its behavior under conditions that simulate operational ones, but they do not allow to talk about a guaranteed service life. In this regard, laboratory tests should include tests as close as possible to operational influences in order to identify the deficiencies of the investigated coatings. The paper discusses the methodological features of autoclave testing with a pressure drop for polymer powder coatings. Autoclave tests simulate operating conditions, but the way they are performed can affect the final result. Autoclave decompression tests were carried out in environments containing CO2 and H2S gases. The effects of pressure release rate, temperature and coating quality were evaluated. Methods for assessing the degradation of coatings after testing are considered. The result of the work is a description of the factors that can affect the results of autoclave decompression tests of polymer anticorrosive coatings.

show abstract

How to Pressurize Autoclaves for Corrosion Testing Under Carbon Dioxide and Hydrogen Sulfide Pressure

Cited by 14 publications

References 0 publications

Optimizing Sour Gas Qualification Testing: Determination and Verification of H2S Solubility from H2S/N2 Gas Mixtures up to 20,000 psig at 70°F

Optimizing Sour Gas Qualification Testing: Determination and Verification of H2S Solubility from H2S/N2 Gas Mixtures up to 20,000 psig at 70°F

Corrosion behaviour of X52 pipeline steel in high H₂S concentration solutions at temperatures ranging from 25°C to 140°C

Investigation of factors influencing on the autoclave tests results of internal anticorrosive polymer coatings

Contact Info

Product

Resources

About

How to Pressurize Autoclaves for Corrosion Testing Under Carbon Dioxide and Hydrogen Sulfide Pressure

Cited by 14 publications

References 0 publications

Optimizing Sour Gas Qualification Testing: Determination and Verification of H2S Solubility from H2S/N2 Gas Mixtures up to 20,000 psig at 70°F

Optimizing Sour Gas Qualification Testing: Determination and Verification of H2S Solubility from H2S/N2 Gas Mixtures up to 20,000 psig at 70°F

Corrosion behaviour of X52 pipeline steel in high H2S concentration solutions at temperatures ranging from 25°C to 140°C

Investigation of factors influencing on the autoclave tests results of internal anticorrosive polymer coatings

Contact Info

Product

Resources

About

Corrosion behaviour of X52 pipeline steel in high H₂S concentration solutions at temperatures ranging from 25°C to 140°C