Promising domestic gas and gas condensate fields are characterized by the presence of CO2 in the composition of the extracted raw materials which (in combination with moisture condensation and a number of other factors) stimulates the intensive development of local corrosion processes). The paper presents the results of studying corrosion of gas production objects using methods of analytical control (gas chromatography with mass spectrometry, X-ray fluorescence spectrometry, X-ray diffraction). It is shown that key parameters (CO2 partial pressure, mineralization, pH factor, total pressure, etc.) should be considered with allowance for their expected changes during the life cycle of the field and production facilities. To determine the ultimate local corrosion rates, corrosion tests were carried out under conditions of moisture condensation. The corrosion development under CO2 conditions is shown to depend on the amount of moisture formed during condensation on metal surfaces, composition and content of the condensate in the vapor phase. Monoethylene (MEG) glycol which is used in gas production as a hydrate formation inhibitor can be also present in the condensed medium. MEG concentration also significantly contributes to the rate of corrosion processes Local carbon dioxide corrosion rate can attain several millimeters per year. Analytical methods can be successfully used in combination with other control methods to predict and monitor a corrosion situation (content of a corrosion inhibitor, presence of the corrosion products or deposits, etc.) at gas production facilities.
Investigation of the corrosiveness of moisture condensation conditions at gas production facilities in the presence of СО2
