Oil field water containing large amount of chloride-ions, oxygen, carbon and hydrogen sulphate is a stimulating agent of initiation and development of electrochemincal processes which are the most harmful type of corrosive and destructive impact on themetal.
The most powerful corrosion excitant is hydrogen sulphate that can be in a form of H2S, HS-S2. Possible combinations of iron with hydrogen sulphate and its disociating forms as a result of interdiffusion with hydrogen will lead to destruction of corrodible steel structures.
Oil field experience preves that the most harmful types of local corrosive damanges can happen due to activity of miccroorganisms. Microbiological corrosion covers 20-50% of total corrosion losses per litre. By adjusting into oil stratum, microorganisms produce sulpgatereducing bacterium(SRB). SRB settle at the surface of metal and bleed hydrogen sulphate and organic acids, e.g. acetic acid which is very aggressive to carbon steel. Bacteria colonies are localised on irregular surface this producing local growth of deep honeycombs, which are even more destructive than purely chemical sulphide corrosion.
In order to protect oil field equipment from chemical and biological corrosion “KARVAN-L” company has developed quite effective and economic water-soluble and oil-soluble corrosion inhibitors.
Corrosion inhibitors are nitrogenated surfactanta, prepared on the basis of natural acids by injection of biocides and film-forming admixtures.
Karvan-1010 reagents are highly effecttive corrosion inhibitor for petroleum industry. Its used for growth inhibition of sulphatereducing bacterium (SRB), prodection from biogical corrosion and from prodection corrosion wather condensates containing dissolved aggressive gases like chlorine hydride, carbon dioxide and hydrogen sulphide. In ceratin conditions reagent has demulsifying features and assists oil dehydration and desalting.
Row 1 protective effect from biological corrosion.
Row 2 protective effect from aaggressive gases H2S, Co2, HCI, O2
At the moment company exucutes bench scale tests of Karvan-102 paraffin inhibitors, compound action with demulsifying and anti-hydrant features, and new highly effective salting inhibitor Karvan-103, which is used depending on conditions of complicated plants.