Industry iron and steel

More than half of the elements in the Periodic Table react with silicon to form one or more silicides. The refractory metal and noble metal silicides ate used in the electronics industry. Silicon and ferrosilicon alloys have a wide range of applications in the iron and steel industries where they are used as inoculants to give significantly improved mechanical properties. Ferrosilicon alloys are also used as deoxidizers and as an economical source of silicon for steel and iron. 

Rare-Earth Silicides. Rare-earth sihcides, in the form of a ferroalloy that contain up to 33% rare earths, are used increasingly by the iron and steel industries. Whereas the term sihcides is no longer used for alloys of this type, it is stih in common usage for these materials. Eor nodular iron, addition... 

The largest consumer of coke is the iron and steel industry. In the United States, ca 600 kg of coke is used to produce a metric ton of steel. Japanese equipment and practice reduce the requirement to 400—450 kg. Coke is also used to gas from the char in one vessel. The reducing gas converts iron oxide to iron in the upper two stages of a second vessel. Steam is converted to hydrogen and reoxidizes the iron in two stages in the lower half of the vessel. 

Continuous-Flow Compressors Continuous-flow compressors are machines where the flow is continuous, unlike positive displacement machines where the flow is fluctuating. Continuous-flow compressors are also classified as turbomachines. These types of machines are widely used in the chemical and petroleum industiy for many services. They are also used extensively in many other industries such as the iron and steel industry, pipeKne boosters, and on offshore platforms for reinjection compressors. Continuous-flow machines are usually much smaller in size and produce much less vibration than their counterpart, positive displacement units. 

Iron and steel industries have been concerned with emissions from their furnaces and cupolas since the industry started. Pressures for control have forced the companies to such a low level of permissible emissions that some of the older operations have been closed rather than spend the money to comply. The companies controlling these operations have not gone out of business but rather have opened a new, controlled plant to replace each old plant. Table 6-3 illustrates the changes in the steelmaking processes that have occurred in the United States. 

The toxic chemical release data obtained from TRI provides detailed information on the majority of facilities in the iron and steel industry in the United States. It also allows for a comparison across years and industry sectors. Reported chemicals are limited however to the 316 reported chemicals. The TRI is important to look at not only from understanding the magnitude and types of pollutants, but from the standpoint of individual plant operations benchmarking their environmental performance against industry averages. 

Table 7. Examples of P2 Practices in the Iron and Steel Industry.

Fisenbarth, M. J. Fume Extraction Hoods in the Iron and Steel Industry. In APCA Speu.airy Proceedings—Air Pollution Control in the Iton and Steel Industry, Chicago, IL,. Apr. [9S1, pp. 28-41. 

About two-thirds of the N2 produced industrially is supplied as a gas, mainly in pipes but also in cylinders under pressure. The remaining one-third is supplied as liquid N2 since this is also a very convenient source of the dry gas. The main use is as an inert atmosphere in the iron and steel industry and in many other metallurgical and chemical processes where the presence of air would involve fire or explosion hazards or unacceptable oxidation of products. Thus, it is extensively used as a purge in petrochemical reactors and other chemical equipment, as an inert diluent for chemicals, and in the float glass process to prevent oxidation of the molten tin (p. 370). It is also used as a blanketing gas in the electronics industry, in the packaging of processed foods and pharmaceuticals, and to pressurize electric cables, telephone wires, and inflatable rubber tyres, etc. 

Worrell, E. Price, L. Martin, N. Faria, J. and Schaeffer, R. (1997). Energy Intensity in the Iron and Steel Industry A Comparison of Physical and Economic Indicators. Energy Policy 25 (7-8) 727-744. 

Worrell, E. Martin, N. and Price, L. (1999). Energy Efficiency and Carbon Emission Reduction Opponumties in the U.S. Iron and Steel Industry. Berkeley, CA Lawrence Berkeley National Laboratory. 

Refractory quality. Refractory lining was first developed mainly for use in the iron and steel industries. It was not until the refractory manufacturers began developing products specifically designed for FCC applications that tremendous improvements in erosion and insulating properties were realized. 

In 1901, the U.S. National Bureau of Standards (NBS) - now the National Institute of Standards and Technology (NIST) - was founded because of the increasing demand for various kinds of standards in the rapidly developing engineering industries. The early history of the NBS reference material program started in 1905 with a cooperative effort within the iron and steel industry whereby industrial analysts helped characterize the individual reference materials. Cooperation with NBS was recognized as a mark of achievement for the laboratory, so this effort served a dual purpose. It both helped the laboratory develop its measurement skills and also helped NIST understand the meastuement problems associated with a given matrix. 

The iron and steel industry is currently on an upsurge because of strong global and local demands. It plays a critical role in the infrastructural and overall economic development of a country. The versatility of steel can be understood from its wide range of applications in the construction, transportation, and process industries. There has been a remarkable growth in world crude steel production, from 189 million metric tons in 1950 to 1244 million metric tons in 2006 (International Iron and Steel Institute, IISI). However, the steel production process is an energy-, raw-material, and labor-intensive process, accounting for major environmental releases.17... 

Source From Energetics, Inc., Energy and Environmental Profile of the U.S. Iron and Steel Industry, DOE/EE-0229, U.S. Department of Energy, Washington, DC, 2000. 

FIGURE 2.4 Flow diagram of the iron-making operation. (From U.S. EPA, Profile of the Iron and Steel Industry, EPA 310-R-95-005, U.S. EPA, Washington, DC, 1995.)... 

The marketable slag makes up about 10 to 15% of the steel output, or 210 to 300 lb/t of steel.1 BOF dust and sludge generated during the cleaning of gases emitted from the BOF represent two of the three largest-volume wastes typically land disposed by the iron and steel industry. 

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