Corrosion inhibitors based on regenerated plant raw material for protection of gas and oil recovery equipment

Abstract

Technology is developed and introduced for preparing a highly efficient corrosion inhibitor based on regenerated plant raw material for protecting gas and oil industry equipment, and supply lines from internal surface corrosion, hydrogenation, and sulfide corrosion cracking, caused by the action of hydrogen sulfidecontaining mineralized aqueous media. Alongside research into the choice of the most stable and economically justified materials and corrosion-resistant coatings used under specific conditions, a significant place is occupied by creation and use of various corrosion inhibitors. However, universal corrosion inhibitors have not so far been found, although a considerable number of new inhibitors have been created for each specific purpose. In Russia and throughout the world, there is some reduction in the use of inhibitors in connection with the spread of production equipment and pipelines manufactured from corrosion-resistant materials, and also with use of corrosion-resistant coatings. In spite of this, the field of application for inhibitors remains considerable. Analysis of the contemporary state of the problem for creation of corrosion inhibitors indicates that with some certainty it is possible to predict a class of compounds that to some measure will exhibit inhibiting properties in some corrosion situation. Currently, for protecting metals of oil industry equipment from hydrogen sulfide corrosion in strongly mineralized media 2-alkyl imidazolene derivatives, prepared by reaction of polyamines with carbonic acids followed by ring formation in a five-membered imidazolene heterocycle, are often used. Corrosion inhibitors, prepared on the basis of 2-alkylimidazolenes from polyethylene polyamides (PEPA) and 2-methyl2-alkylhexane acids at 240‐280°C [1], and also from a mixture of 1-dimethylaminoethyl- and (aminoethyl)-2-isoalkyl-2-imidazolenes [2], exhibit low colloidal-chemistry properties, often stratified during shipment and storage, and capable of being salted out during use in highly-mineralized hydrogen sulfide-containing media. A specific disadvantage is displayed by a corrosion inhibitor that is a mixture of 2-alkyl imidazolene derivatives and amides of higher isomeric α-branched monocarbonic acids (HIA) with aromatic hydrocarbons, surface-active substances (SAS), and alcohols [3]. Disadvantages of these corrosion inhibitors are an increased capacity for foaming, use of expensive aromatic hydrocarbons, and insufficient efficiency in the later and concluding stages of oil and gas development. Technology for corrosion inhibitor preparation [3] has been developed by us, and inhibitors are produced at the Kaustik company in Sterlitamak under the names Azimut-14, Azimut-14M, and Vikor. Corrosion inhibitor Vikor is classified as a combined action reagent, i.e., an inhibitor and bactericide, and it also protects metal from hydrogenation. Use of this inhibitor provides suppression of dangerous micro-organism corrosion development, and protection of equipment from the corrosive action of oil industry media. We have also developed technology for preparation of a corrosion inhibitor intended for protecting gas- and oilrecovery equipment operating in highly mineralized hydrogen sulfide-containing media, with the attraction of less expensive