The mixture of dicyclohexilamine and oleylamine as corrosion inhibitor for mild steel in NaCl solution saturated with CO2 under both continual immersion and top of the line corrosion

Abstract

This paper presents a comprehensive method to evaluate the mixture of dicyclohexilamine and oleylamine (DCHA+OA) as corrosion inhibitor for mild steel in CO2 environment in liquid and vapor phase. Corrosion inhibitor volatile properties were investigated in order to determine if DCHA+OA can be used to control the severity of the top of the line (TLC) corrosion attack. Corrosion measurements were performed using electrochemical impedance spectroscopy, linear polarization resistance, potentiodynamic sweep measurements, as well as the electrical resistance measurements and weight loss measurements, in order to determine the inhibitive performances of dicyclohexilamine and oleylamine. In order to define surface morphological characteristics scanning electron microscopy technique was applied. The electrochemical study and weight loss measurements indicated that DCHA+OA significantly decreased the corrosion rate in liquid phase when 50 ppm of DCHA+OA was added. Scanning electron microphotographs indicated protective inhibitor film has formed on the steel surface and revealed that good protection was achieved, along with the decrease in the corrosion rate determined by weight loss and electrochemical techniques. Using electrical resistance measurements in vapor phase it was shown that concentration of 1000 ppm DCHA+OA significantly decreased the corrosion rate at the top of the line, only when it was carried there within its own foam and not due its volatility

Electrochemistry of carbon dioxide corrosion mitigation using tall oil diethylenetriamine imidazoline as corrosion inhibitor for mild steel

“…A variety of organic compounds which generally contain nitrogen, oxygen, phosphorus, or sulfur heteroatoms act as corrosion inhibitors for steels. These compounds include amines, alkyl imidazoline salts, quaternary ammonium compounds, alkyl pyridinium salts, alkyl amides, triazoles, oxadiazoles, thiourea derivatives, thiosemicarbazide, thiocyanates, and the combinations thereof .…”

Evaluation of a Novel Top-of-the-Line Corrosion (TLC) Mitigation Method in a Large-Scale Flow Loop

“…It should have consequently led to the formation of strong chemical bonds that would allow the product to remain on the pipe wall for long periods of time between treatments. 11 The objective of the work described in this paper was to test the applicability of this novel TLC mitigation method in a large-scale flow loop. Hydrodynamic tests in the flow loop were performed in order to investigate the foam stability as a function of gas velocity, as well as the effect of different foaming-agent concentrations on the consistency and strength of the foam.…”

“…Corrosion inhibition is one of the most commonly used methods for corrosion control in carbon steel equipment for oil and gas production; however, conventional mitigation methods can fall short in protecting the top of the line, since conditions do not allow the inhibitor to reach the top sections of the wall. [11][12] Gravity effects, low flow rates, and stratified flow make the transfer of the corrosion inhibitor to the top of the pipe difficult. The most common method used in the case of TLC is batch treatment, but this results in regular decreases in production rates and consequently in revenue.…”

Development of an effective method for internal pipeline corrosion control in the presence of CO2

“…Corrosion inhibitors contain different functional groups, usually polar head (fatty acids, amines, imidazolines, oxygen, sulphur or phosphorus containing species, quaternary amines) and long hydrocarbon chain (typically C14-C18), which promote the binding of inhibitor molecules to the metal surface [12][13][14][15][16][17]. Imidazoline based corrosion inhibitors are cationic surface active compounds widely used for protecting pipelines from CO 2 corrosion in the oil and gas industry [18][19][20][21].…”

“…Conventional mitigation methods can fall short in protecting the top of the line since the conditions do not allow the inhibitor to reach the top sections of the wall [17]. A novel idea consists of injecting the corrosion inhibitor within a foam matrix and delivering the corrosion inhibitor to locations where condensation occurs.…”