Corrosiveness of oils

The role of bacteria in the corrosion of oil field equipment, TPC3, National Association of Corrosion Engineers, Houston, 1976. 

Amine salts of ether carboxylates inhibit internal corrosion of oil storage tanks and pipelines [230]. Furthermore it is possible to use ether carboxylates as corrosion and scale inhibitors for industrial recirculating cooling water systems, metalworking fluids, and hydraulic fluids [28,231-233]. 

High temperature corrosion of oil fired and other combustion equipment, probably proceeds by similar mechanisms to those in coal fired boilers. Differences will depend on the mineral content in the particular fuel and its chemical composition. 

Corrosion brings nothing but loss and the corrosion of oil and gas facilities will result in loss of materials, resources, time, and reputation if not properly handled [2]. When the control and mitigation of corrosion risk are properly implemented, the frequency of corrosion will be reduced. It is a known fact that risk cannot be eliminated, but the possibilities of reduction or minimization are possible, and that can only be achieved when the measures outlined in this chapter are strictly adhered to. 

Chapter 21 Safety and Risk Implications of Corrosion of Oil and Gas Facilities.655... 

Nesic, Srdjan 2007. Key issues related to modelling of internal corrosion of oil and gas pipelines - A review. Corrosion Science 49 12) 4308-4338. 

During oil production from a subsea well sand may be produced. In order to control sand formation and retain potential erosion and corrosion of oil production pipelines, several safety barriers are in place. 

A.A. Gonik 2005. On the local inner corrosion of oil and gas pipelines in the west-siberian fields and its prevention. Protection of Metals 41(5), 487-490. 

S. Papavinasam, R.W. Revie, W.I. Friesen, A. Doiron, T. Panneerselvam 2006. Review of models to predict internal pitting corrosion of oil and gas pipelines. Corrosion Reviews 24 (3-4), 173-230. S. Papavinasam, A. Doiron, R.W. Revie, V. Sizov 2007. Model predicts internal pitting corrosion of oil, gas pipelines. Oil and Gas Journal 105, 68-72, 74. 

V.V. Zav yalov 2003. Corrosion of oil-field pipelines. Zashchita Metallov 39 (3), 306-310. 

Apart from the reduction of extraction properties, O2 supposedly accelerates the corrosion of oil processing equipment. Moreover, O2 may react with the reservoir oil making its extraction even more difficult. Thus, strict limits with respect to the residual O2 content have been defined for EOR applications. Metz et al. for instance, mention a residual O2 content of 10 ppm or lower, while Liljedahl et al allow 100 ppm O2. After all, CO2 purity requirements for EOR applications are highly site specific. Thus, it is only possible to quantify them in a genertic way, however they are not applicable to all reservoirs. 

Performance can be illustrated for example by the time necessary for deaeration or de-emulsification of oils, anti-rust properties, copper strip corrosion test, the flash point in closed or open cup, the cloud and pour points, the foaming characteristics, etc. 

Hydrogen chloride released dissolves in water during condensation in the crude oil distillation column overhead or in the condenser, which cause corrosion of materials at these locations. The action of hydrochloric acid is favored and accelerated by the presence of hydrogen sulfide which results in the decomposition of sulfur-containing hydrocarbons this forces the refiner to inject a basic material like ammonia at the point where water condenses in the atmospheric distillation column. 

Oxidation first produces soluble oxygenated compounds of molecular weights between 500 and 3000 that increase the viscosity of oil then they polymerize, precipitate, and form deposits. Oxidation also causes formation of low molecular weight organic acids which are very corrosive to metals. 

Uses. Propargyl alcohol is a component of oil-well acidizing compositions, inhibiting the attack of mineral acids on steel (see Corrosion and CORROSION control). It is also employed in the pickling and plating of metals. 

Petroleum and Natural Gas. Over 90% of the 428,000 t of caustic soda used in the petroleum and natural gas industry is used to process oil and gas into marketable products, especially by removing acidic contaminants. The remainder is used primarily to decrease corrosion of drilling equipment and to increase the solubiUty of drilling mud components by maintaining an alkaline pH (6). 

Rust inhibitors usually are corrosion inhibitors that have a high polar attraction toward metal surfaces and that form a tenacious, continuous film which prevents water from reaching the metal surface. Typical mst inhibitors are amine succinates and alkaline-earth sulfonates. Rust inhibitors can be used in most types of lubricating oils, but factors of selection include possible corrosion of nonferrous metals or formation of emulsions with water. Because mst inhibitors are adsorbed on metal surfaces, an oil can be depleted of its mst inhibitor. In certain cases, it is possible to correct the depletion by adding more inhibitor. 

Beiirings. Silver is plated in all main-shaft bearings of jet engines because the silver provides a low coefficient of friction and superior fatigue and corrosion resistance, and has sufficient lubricity to serve as an emergency lubricant in case of oil failure. 

The derivatives used in corrosion inhibitor formulations for down-hole use constitute a significant industrial appHcation for polyamines. Again, mono- and bisarnidoamines, imidazolines, and polyamides made from the higher polyamines are the popular choices. The products made from DETA and fatty acids have been widely used (308). A wide variety of other polyamine-based, corrosion inhibiting derivatives have been developed, generally incorporating some form of oil-soluble or od-dispersible residue. Sulfur and its derivatives are also used in these polyamine-based corrosion inhibitors on... 

In addition to films that originate at least in part in the corroding metal, there are others that originate in the corrosive solution. These include various salts, such as carbonates and sulfates, which may be precipitated from heated solutions, and insoluble compounds, such as beer stone, which form on metal surfaces in contac t with certain specific products. In addition, there are films of oil and grease that may protect a material from direct contact with corrosive substances. Such oil films may be apphed intentionally or may occur naturally, as in the case of metals submerged in sewage or equipment used for the processing of oily substances. 

Petroleum greases and oils can be excellent corrosion inhibitors on a variety of alloys. The hydrophobic layer produced by oil or grease can prevent water from contacting surfaces and can, therefore, almost eliminate corrosion. Unfortunately, the addition of oil and grease cannot be recommended as a corrosion-reduction measure in cooling water systems for three basic reasons. 

Many thousands of miles of steel pipeline have been laid under, or in contact with, the ground for the long-distance transport of oil, natural gas, etc. Obviously corrosion is a problem if the ground is at all damp, as it usually will be, and if the depth of soil is not so great that oxygen is effectively excluded. Then the oxygen reduction reaction... 

---