EFFECTIVENESS OF INHIBITOR PROTECTION OF CARBON AND LOW-ALLOY STEELS AT ELEVATED TEMPERATURES

In the article the authors consider the problem of CO2-corrosion of carbon and low-alloy steels under elevated temperature. The problem of CO2-corrosion of steels is one of the most important in the operation of pipeline systems. When involving viscous and super-viscous oils in the development for the extraction of which steam injection technologies are used, usage of corrosion inhibitors for elevated temperature conditions is actual. The article presents results of studies of the effectiveness of corrosion inhibitors in pre-calculated maximum cost-effective dosages on a water-oil emulsion model and on a formation water model at temperatures of 60–80 °C and 110 °C under CO2-corrosion. It has been shown that the flow regime of the water-emulsion mixture significantly affects the corrosion rate. Water-soluble corrosion inhibitors reduce the corrosion rate in the studied temperature range, but do not provide the required corrosion rate level due to the low adsorption capacity in the tested dosages.