Corrosion petroleum refining

NACE International Standard RP0472-95, Methods and Controls to Prevent In-Service Environmental Cracking of Carbon Steel Weldments in Corrosive Petroleum Refining Environments. 

To complicate the issue even more, another NACE MR0103 was issued in April 2003 - yet another new standard - Materials Resistant to Sulphide Stress Cracking in Corrosive Petroleum Refining Environments. ... 

SSC of carbon steel weldments in hydrogen sulfide service is controlled by the following procedures described in NACE Standard Methods and Controls to Prevent In-Service Cracking of Carbon Steel (P-1) Welds in Corrosive Petroleum Refining Environments (RP0472). This includes... 

NACE International. 2005. Methods and controls to prevent in-service environmental cracking of carbon steel weldments in corrosive petroleum refining environments, NACE Standard RP0472-2005, Houston NACE International. 

Naphthenic acid corrosion has been a problem ia petroleum-refining operations siace the early 1900s. Naphthenic acid corrosion data have been reported for various materials of constmction (16), and correlations have been found relating corrosion rates to temperature and total acid number (17). Refineries processing highly naphthenic cmdes must use steel alloys 316 stainless steel [11107-04-3] is the material of choice. Conversely, naphthenic acid derivatives find use as corrosion inhibitors ia oil-weU and petroleum refinery appHcations. 

Alkali Treatment. Caustic washing is the treatment of materials, usually products from petroleum refining, with solutions of caustic soda. The process consists of mixing a water solution of lye (sodium hydroxide or caustic soda) with a petroleum fraction. The treatment is carried out as soon as possible after the petroleum fraction is distilled, since contact with air forms free sulfur, which is corrosive and difficult to remove. The lye reacts either with any hydrogen sulfide present to form sodium sulfide, which is soluble in water, or with mercaptans, foUowed by oxidation, to form the less nocuous disulfides. 

Hydrogen fluoride Catalyst in some petroleum refining, etching glass, silicate extraction by-product in electrolytic production of aluminum Petroleum, primary metals, aluminum Strong irritant and corrosive action on all body tissue damage to citrus plants, effect on teeth and bones of cattle from eating plants... 

Sulphur dioxide Combustion of coal, oil and other sulphur-containing fuels Petroleum refining, metal smelting, paper-making Vegetation damage Sensory and respiratory irritation Corrosion Discoloration of buildings... 

Spent caustic solutions from petroleum refining. Petrochemical refineries use caustics to remove acidic compounds such as mercaptans from liquid petroleum streams to reduce produced odor and corrosivity as well as to meet product sulfur specifications. Spent liquid treating caustics from petroleum refineries are excluded from the definition of solid waste if they are used as a feedstock in the manufacture of napthenic and cresylic acid products. U.S. EPA believes that spent caustic, when used in this manner, is a valuable commercial feedstock in the production of these particular products, and is therefore eligible for exclusion. 

Uses/Sources. Corrosion-resistant alloys, electroplating, production of catalysts, nickel-cadmium batteries nickel subsulfide (NisS2) is encountered in the smelting and refining of certain nickel ores and may be formed in petroleum refining from the use of nickel catalysts. 

High-temperature corrosion and wear is encountered in various industries such as waste incineration, fossil energy, pulp and paper, petroleum refining, chemical and petrochemical, mining and smelting operations. One of the methods to combat corrosion and wear and its control is to select suitable material, i.e., an alloy, for the plant design and maintenance. The selection of proper material for plant design and fabrication is followed... 

Petroleum Refining Process Corrosion, Crude Fractionation Units,... 

Figure 1.12 Comparison of sulfur levels vs carbon steel corrosion rates.9 Petroleum Refining Process Corrosion, Crude Fractionation Units, and Utilities 21...

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