TY - THES

T1 - Investigation and Mitigation of Tubing Corrosion Process

AU - Gabdinurov, Galinur

N1 - embargoed until null

PY - 2020

Y1 - 2020

N2 - The purpose of the thesis is to improve the efficiency of oil well operation in the fields of the West-Siberian region. One of the main factors complicating oil well operation and leading to premature tubing failures in this region is carbon dioxide corrosion. The dynamic of the corrosion process, chemical methods of its preventing (inhibitors), and protection of metal by passivation were investigated in this thesis. A set of experimental laboratory studies were implemented to determine the corrosive aggressiveness of the fluids from Western Siberia oilfields and further evaluation of inhibitor protective ability. Corrosion aggressiveness of media was estimated by the gravimetric method. The method consists of the determination of weight loss of metal samples during their stay in inhibited and non-inhibited test media. To verify the passivation effect, the technology of cold bluing (steel blackening using a chemical mixture based on selenium dioxide) was implemented in laboratory work. According to the results of laboratory tests, the maximum corrosion rate in the carbon dioxide aqueous medium was reached 0.1528 g/m2h for field X and 0.1736 g/m2h for field Y. The application of corrosion inhibitors made it possible to increase the corrosion resistance of the samples. According to the results of performed laboratory tests with model media under conditions of carbon dioxide corrosion, the best inhibiting ability was shown by the chemical reagents SNPCH-6418 B and FLEC-IK201 mB with the maximum effective dosage up to 30 mg/dm3. The passivation effect approved that the chemical methods of corrosion protection based on the formation of protective films on the metal surface are robust security measures. During the experiment, the improvement of corrosion resistance of samples was established. Based on the gravimetric method, the degree of protection in the environment of inhibited SNPH-6418B is 89,2%, and in the environment of inhibited SONCOR-9027A - 79,3% accordingly. Thus, the protective ability of the metal passivation technology in combination with inhibitor increases the corrosion resistance of metal by 17% on average. The technology of the joint application of corrosion inhibitors and metal chemical passivation has been studied for the first time. This development will improve the reliability and durability of tubing and prevent their premature destruction due to corrosion processes.

AB - The purpose of the thesis is to improve the efficiency of oil well operation in the fields of the West-Siberian region. One of the main factors complicating oil well operation and leading to premature tubing failures in this region is carbon dioxide corrosion. The dynamic of the corrosion process, chemical methods of its preventing (inhibitors), and protection of metal by passivation were investigated in this thesis. A set of experimental laboratory studies were implemented to determine the corrosive aggressiveness of the fluids from Western Siberia oilfields and further evaluation of inhibitor protective ability. Corrosion aggressiveness of media was estimated by the gravimetric method. The method consists of the determination of weight loss of metal samples during their stay in inhibited and non-inhibited test media. To verify the passivation effect, the technology of cold bluing (steel blackening using a chemical mixture based on selenium dioxide) was implemented in laboratory work. According to the results of laboratory tests, the maximum corrosion rate in the carbon dioxide aqueous medium was reached 0.1528 g/m2h for field X and 0.1736 g/m2h for field Y. The application of corrosion inhibitors made it possible to increase the corrosion resistance of the samples. According to the results of performed laboratory tests with model media under conditions of carbon dioxide corrosion, the best inhibiting ability was shown by the chemical reagents SNPCH-6418 B and FLEC-IK201 mB with the maximum effective dosage up to 30 mg/dm3. The passivation effect approved that the chemical methods of corrosion protection based on the formation of protective films on the metal surface are robust security measures. During the experiment, the improvement of corrosion resistance of samples was established. Based on the gravimetric method, the degree of protection in the environment of inhibited SNPH-6418B is 89,2%, and in the environment of inhibited SONCOR-9027A - 79,3% accordingly. Thus, the protective ability of the metal passivation technology in combination with inhibitor increases the corrosion resistance of metal by 17% on average. The technology of the joint application of corrosion inhibitors and metal chemical passivation has been studied for the first time. This development will improve the reliability and durability of tubing and prevent their premature destruction due to corrosion processes.

KW - corrosion

KW - protection

KW - inhibitor

KW - tubing

KW - passivation

KW - Schutz

KW - das Rohr

KW - Korrosion

KW - Bohrloch

KW - Passivierung

M3 - Master's Thesis

ER -