Petroleum industry, corrosion inhibitors

The use of various substances as additives to process streams to inhibit corrosion has found widespread use and is generally most economically attractive in recirculation systems, however, it has also been found to be attractive in some once-through systems such as those encountered in the petroleum industry. Typical inhibitors used to prevent corrosion of iron or steel in aqueous solutions are chromates, phosphates, and silicates. In acid solutions, organic sulphides and amides are effective. 

Lubricants. Petroleum lubricants continue to be the mainstay for automotive, industrial, and process lubricants. Synthetic oils are used extensively in industry and for jet engines they, of course, are made from hydrocarbons. Since the viscosity index (a measure of the viscosity behavior of a lubricant with change in temperature) of lube oil fractions from different cmdes may vary from +140 to as low as —300, additional refining steps are needed. To improve the viscosity index (VI), lube oil fractions are subjected to solvent extraction, solvent dewaxing, solvent deasphalting, and hydrogenation. Furthermore, automotive lube oils typically contain about 12—14% additives. These additives maybe oxidation inhibitors to prevent formation of gum and varnish, corrosion inhibitors, or detergent dispersants, and viscosity index improvers. The United States consumption of lubricants is shown in Table 7. 

Petroleum Production and Refining. Specific polyamine derivatives are used in the petroleum production and refining industries as corrosion inhibitors, demulsifiers, neutralizers, and additives for certain operations. 

Corrosion inhibitors are the subject of several topics in petroleum industries, such as transport and completion. They are detailed in Chapter 6. 

The history of corrosion inhibitors and neutralizers and their invention, development, and application in the petroleum industry is documented by a review of Fisher [605]. Early corrosion inhibitor applications in each of the various segments of the industry, including oil wells, natural gas plants, refineries, and product pipelines, are reviewed. 

The normal industrial practice for controlling the internal corrosion of petroleum pipelines is to use coatings, nonmetallic pipeline materials, or corrosion inhibitors. Corrosion inhibitors, which are used for the protection of oil pipelines, are often complex mixtures. 

Industrial applications of corrosion inhibitors are too numerous to cover in the present context. The inhibitor industry amounts to several billion dollars annually. Applications of inhibitors in petroleum production, oil and gas wells and pipelines, potable water, water cooling towers, acid systems, automobile antifreeze systems, paints, boiler waters,... 

Marchon . [Albright Wilson Am.] Catalyst in hydrogenation reactions corrosion inhibitor for petroleum industry. 

Vanlube. [R.T. Vanderbilt] Antioxidant, andwear, andscuff, extreme pressure agent, corrosion inhibitor, metal deacd-vator for industrial lubricants, petroleum fittls, solvents. 

Witcor. [Witco] Corrosion and scale inhibitor, surfactant for petroleum industry, water treatment... 

Witcamine . [Witco/Organics Witco SA] Amines emulsifin, lubricant wettii agott penetrant corrosion inhibitor, antistat diq>ersant for water treatment petroleum industry, metal processing, textiles, ore flotation, leather. 

OTHER COMMENTS used in the rubber and petroleum industry used as a corrosion inhibitor in iron, steel and metal industries used as a selective solvent for the removal of impurities from oils, fats, and waxes useful in flotation agents, dyes, and pharmaceuticals. 

Very often the long experience with chemicals operating as corrosion inhibitors, e. g. in the oil field, gas or petroleum industry, is taken as an example for the successful use of corrosion inhibitors for many decades. This undoubtedly is true and the overwhelming majority of literature on corrosion inhibitors deals with the effects of inhibitors on uniform corrosion, e. g. of steel in acidic or neutral solutions, where they can be classified into [2] a) adsorption inhibitors, acting specifically on the anodic or on the cathodic partial reaction of the corrosion process or on both reactions (mixed inhibitor), b) JUm-forming inhibitors, blocking the surface more or less completely, and c) passivators, favouring the passivation reaction of the steel (e. g. hydroxyl ions). 

The major industries that use corrosion inhibitors are petroleum production and refining, chemical and heavy industrial manufacturing, and the product additive industry. The usage summary of corrosion inhibitors in various industries is given in Table 4.9. 

The data in Table 4.9 show that the largest consumption of corrosion inhibitors is in the oil industry with the single highest amount in the petroleum refining industry. 

Corrosion Inhibitors and Their Applications in the Petroleum Industry... 

M. Miksic, A.Y. Furman, M.A. Kharshan (2009). Effectiveness of the corrosion inhibitors for the petroleum industry under various flow conditions. NACE, Paper 09573, Corrosion 2009, USA. 

The petroleum industry generally solves the emulsion problem by adding demulsifiers in an ad hoc manner, often based on simple bottle tests. There are many problems associated with this solution. First, the chemical composition of a given well changes with time and can in a worst-case scenario result in a composition totally incompatible with the given demulsifier. Second, little is known about the exact interaction between demulsifiers and other chemical additives (e.g., corrosion inhibitors and flow enhancers ). One may, flierefore, create a new problem by solving another. 

Chem. Descrip. 1-Hydroxyethyl 2-coconut imidazoline Uses Surfactant, wetting agent, emulsitier, detergent, thickener, corrosion inhibitor, antistat tor agric. emulsions, industrial cleaners, paints/ coatings, plastics, and petroleum applies. 

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