Martin Foss

Effect of Corrosion Inhibitors and Oil on Carbon Dioxide Corrosion and Wetting of Carbon Steel with Ferrous Carbonate Deposits

Abstract The wettability of the steel surface is an important factor codetermining the risk of corrosion in multiphase pipelines for transportation of oil and gas. The present paper deals with the ...

Oil Wetting and Carbon Dioxide Corrosion Inhibition of Carbon Steel with Ferric Corrosion Products Deposits

Abstract Wettability of carbon steel with corrosion product films (iron carbonate [FeCO3], FeCO3 with oxidized surface, and rust [FeO(OH)]) was investigated through contact angle and inhibitor perf...

Alteration of Wettability of Corroding Carbon Steel Surface by Carbon Dioxide Corrosion Inhibitors-Effect on Carbon Dioxide Corrosion Rate and Contact Angle

Abstract The wettability of the steel surface is an important factor co-determining the risk of corrosion in multiphase pipelines for transportation of oil and gas. The effect of carbon dioxide (CO2) corrosion inhibitors on the wettability of carbon steel was investigated in the present paper. Also investigated was the effect of oil on the performance of these inhibitors. Three inhibitors were investigated. Two of them were commercial inhibitor-based chemicals: an oleic imidazoline salt (OI) and a phosphate ester (PE). The third was cetyltrimethylammonium bromide (CTAB), a well-characterized quaternary ammonium compound. A refined, low-aromatic oil product was used in the tests. The wettability of the corroding carbon steel surface was studied by contact angle measurements (25°C, 1 bar CO2, 3 wt% sodium chloride [NaCl]). Both oil-in-water and water-in-oil experiments were performed. The effect of the inhibitor/oil interactions were also studied in CO2 corrosion tests where the steel specimens were alterna...

Adsorption of Corrosion Inhibitors onto Iron Carbonate (FeCO3) Studied by Zeta Potential Measurements

The adsorption of cetyl trimethyl ammonium bromide (CTAB) and two commercial inhibitor base chemicals, an oleic imidazoline salt (OI) and a phosphate ester (PE), onto iron carbonate (FeCO3), was studied by zeta potential measurements in a 0.1 wt% sodium chloride (NaCl) solution under 1 bar CO2 at 22°C, in the absence and presence of a refined low-aromatic oil. The zeta potential of oil-in-water emulsion droplets was also determined. Surface tension of 0.1 wt% and 3 wt% brines was measured as a function of inhibitor concentration. The isoelectric point was pH 6.0 in the 0.1 wt% NaCl solution under 1 bar CO2. The results show that all three inhibitor compounds adsorbed onto the iron carbonate particles both at pH 4.0 and pH 6.0. Adsorption on both negatively charged surfaces and surfaces with no charge were thus found for all inhibitors. The addition of oil had no significant effect on the measured zeta potential on iron carbonate particles.

Measurements of Zeta Potential on Corroding, High-Purity Iron Particles: Influence of Corrosion Inhibitors

Adsorption of cetyl trimethyl ammonium bromide (CTAB), and two commercial inhibitor base chemicals; an oleic imidazoline salt (OI) and a phosphate ester (PE), onto high purity, corroding iron particles was studied by zeta potential measurements in a 0.1 Wt% sodium chloride (NaCl) solution under 1 bar CO2 at 22°C. The particles were exposed to the inhibitor compounds for 24 hours before measurements were done. The results show that the measured zeta potential in the absence of inhibitor is zero at both pH 4.0 ± 0.2 and pH 5.8 ± 0.2. It is concluded that this might be caused by the electrochemical reactions occurring at the steel surface when placed in an electrical field. When adding inhibitor, which slows the electrochemical reactions at the steel surface, the zeta potential moves away from zero and an adsorption isotherm is obtained for all three inhibitors. The measured potential is probably a mixed potential where the apparent potential measured is a combination of the potential at the shear plane and a contribution form the electrochemical reactions occurring on the surface.

Preparation and Characterization of Reference Fluids to Mimic Flow Properties of Crude Oil Emulsions (w/o)

The multiphase flow models, such as OLGA® and LedaFlow®, have been developed based on the multiphase flow experiments, where base oils have been widely used. However, physicochemical properties of the base oils and crude oils are mostly not similar and therefore liquid–liquid flow properties of them in the pipes can be very different. Consequently, it is very important to get the fluids behave in a similar way with the produced crude oils. In this study, the reference fluids with flow properties similar to the produced crude oils and their corresponding emulsions have been prepared. The steps involved to prepare the reference fluids for crude oils were also discussed. GRAPHICAL ABSTRACT

Foreword: The Bridge between Colloid Chemistry and Fluid Dynamics

GRAPHICAL ABSTRACT