Annual steel

Iron comprises approximately 4.7% of the Earth s crust. The enormous quantities of this metal in the earth core are prerequisite for the magnetic field that shields the planet from cosmic radiation and enables life. The ubiquitous availability of iron and its ability to adjust its oxidation state, redox potential and electron spin state makes it suited to participate in a large number of chemical reactions. Thus, iron has become essential for animals, plants, fungi and most bacteria, ivhere it functions in a ivide variety of iron-dependent enzymes and metal proteins. To avoid deficiency symptoms, mechanisms have evolved in these organisms to maintain iron homeostasis in situations of scarce supply, but also to avoid oxidative stress as mediated by Fenton chemistry ivhen supply is excessive. In industry, iron is used in over 2500 varieties of steel, each with different physical properties. In fact, annual steel production is almost as high as that of all other metals combined hence the environmental effects of iron must also be considered. 

The importance of extracurricular activities to students academic performance and progress is now recognized by many educators and deemed an integral part of student life. In Chapter 4, the most relevant student organizations on many campuses are described with emphases on student competitions and scholarship opportunities. The competitions sponsored by ASCE (American Society of Civil Engineers), the annual steel bridge competition and the annual concrete canoe competition, are described in some detail to encourage student participation. 

Corrosion, from the Latin corrodere, means to chew away , to attack . It is estimated that corrosion destroys one quarter of the world s annual steel production, which corresponds to about 150 million tons per year, or 5 tons per second. Of course, corrosion is not limited to steel but affects all materials metals, polymers and ceramics. It is the result of chemical and/or physical interactions between the material and its environment. Examples of the corrosion phenomena include ... 

Corrosion has been described as an insidious consumer of our stocks of raw material. A rough estimate suggests that corrosion costs 4% of Gross National Product. This means that a third of the annual steel output converts to rust and causes the premature ageing of machinery. Thus protection against corrosion is very important. 

Unprotected steel corrodes at a rate which is generally assumed to be 0.1 to 0.2mm per annum. Factors that influence the actual rate of corrosion include the maintenance program applied by the owner - particularly preservation of protective coatings, efficiency of cathodic protection systems in ballast tanks, corrosive properties of the cargo carried and environmental factors such as temperature and humidity. Under extreme conditions it has been known for the annual rate of corrosion on unprotected steel exposed on both surfaces to approach 1mm. 

N. Dobbs and co-workers, "Design of Steel, Masonry and Precast Concrete Stmctures to Resist the Effects of HE Explosions" in 17th Annual Dept, of Defense Explosive Safety Seminar,NT S, Springfield, Va., 1976. 

The United States has the largest metal powder producing and consuming industry of any country. The value of U.S. metal powder shipments, including paste and flake, was 1,243 bHHon in 1992. Approximately 307,000 t of Hon and steel powder and 21,000 t of copper and copper-base powders were shipped in North America in 1994. Estimated annual world metal powder production exceeds 950,000 t. 

American Ligurian, Inc. (Stanford, Connecticut) is marketing a pyrolysis process developed in Italy, which generates steam for hot water, air heating, dryers, kilns, and similar installations. A modular plant produces 8000 kg/h of steam from 1 tih of tires. The pyrolysis process produces 0.9 t of fuel ok, 270 t of steel, and 54 t of ash annually. Gas emissions meet the strictest environmental standards (16). 

About 800 million metric tons of raw steel is produced annually throughout the world. Its usehilness is enhanced by the fact that it is inexpensive. The price as of the mid-1990s ranged from ca 440/kg for the common grades to several dollars per kg for special steels such as certain tool steels. Prices have remained relatively constant since the early 1980s. 

Technical data from proceedings of various ISS Mechanical Working and Steel Processing Annual Conferences. 

Production is practiced at many hundreds of metric tons annually by batchwise or semicontinuous operation in automated glass and stainless steel equipment typical of fine chemical manufacture. World production in 1995 was estimated at about 3000 MT with sales prices in the United States in the range of 22— 30 per kilogram. 

American Water Works Association (AWWA) The association has many standards deahng with water handling and storage. A list of its publications is given in the AWWA Handbook (annually). AWWA DlOO, Standard for Steel Tanks—Standpipes, Reservoirs, and Elevated Tanks for Water Storage, contains rules for design and fabrication. 

Red lead (Pb304) is manufactured on the 20000-tonne scale annually and is used primarily as a surface coating to prevent corrosion of iron and steel (check oxidation-reduction potentials). It is also used in the production of leaded glasses and ceramic glazes and. very substantially, as an activator, vulcanizing agent and pigment in natural and artificial rubbers and plastics. 

Anhydrous HF was first produced commercially in the USA in 1931 and in the UK from about 1942. By 1992 some eighteen countries were each producing at least 3000 tonnes pa with North America accounting for some 330000 tonnes of the estimated annual world production of about 875 000 tormes, A further 205 000 tonnes was used captively for production of AIF3. Price in 1990 was about l.50/kg for the anhydrous acid and somewhat less for 70% acid. The primary suppliers ship HF in tank-cars of 20-91-tonne capacity and the product is also repackaged in steel cylinders holding 8.0-900 kg (2.7-635 kg in the UK). Lecture bottles contain 340 g HF. The 70% acid is shipped in tank-cars of 32-80-tonne capacity, tank trucks of 20-tonne capacity, and in polyethylene-lined drums holding 114 or 208 I,... 

Pure iron, when needed, is produced on a relatively small scale by the reduction of the pure oxide or hydroxide with hydrogen, or by the carbonyl process in which iron is heated with carbon monoxide under pressure and the Fe(CO)5 so formed decomposed at 250°C to give the powdered metal. However, it is not in the pure state but in the form of an enormous variety of steels that iron finds its most widespread uses, the world s annual production being over 700 million tonnes. 

American Iron and Steel Institute (199S). Annual Statistical Report 19SS. Washington, DC Office of Energy Markets and End Use. 

De Beer, J. Worrell, E. and Blok, K. (1998). Future Technologies for Energy Efficient Iron and Steel Making. Annual Review of Energy 3nd the Environment 23 123-205. 

From time to time astronomical estimates are made of the annual destruction of metals, particularly iron and steel, by corrosion (Section 1.1). Paint is one of the oldest methods used for delaying this process and consequently it is somewhat surprising that its protective action has only recently been systematically examined. 

Production data are compiled annually by the American Chemical Society and published in Chemical and Engineering News. This table is based on the information about production in 2005 that was published in the July 10, 2006, issue. Water, sodium chloride, and steel traditionally are not included and would outrank the rest if they were. Hydrogen is heavily used but almost always on site as soon as it has been prepared. 

Spent pickle liquor is considered a hazardous waste (K062) because it contains considerable residual acidity and high concentrations of dissolved iron salts. For example, spent pickle liquor and waste acid from the production of stainless steel is considered hazardous. The hazardous constituents in K062 are lead, nickel, and hexavalent chromium. Waste pickle liquor sludge generated by lime stabilization of spent pickle liquor is not considered hazardous unless it exhibits one or more of the characteristics of hazardous waste. An estimated 6 million tons of spent pickle liquor are generated annually in the U.S.1... 

Source From Noureldin, A.S. and McDaniel, R.S., Evaluation of Steel Slag Asphalt Surface Mixtures, presented at the 69th annual meeting, Transportation Research Board, Washington, January 1990. 

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