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SINTER PLANT/DESULPHURIZATION
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Sintering is the process of compacting and forming a solid mass of material by heat and/or pressure without melting it to the point of liquefaction.
Sintering happens naturally in mineral deposits or as a manufacturing process used with metals, ceramics, plastics, and other materials. The atoms in the materials diffuse across the boundaries of the particles, fusing the particles together and creating one solid piece. Because the sintering temperature does not have to reach the melting point of the material, sintering is often chosen as the shaping process for materials with extremely high melting points such as tungsten and mollybednum. The study of sintering in metallurgy powder-related processes is known as powder metallurgy. An example of sintering can be observed when ice cubes in a glass of water adhere to each other, which is driven by the temperature difference between the water and the ice.Examples of pressure-driven sintering are the compacting of snowfall to a glacier, or the forming of a hard snowball by pressing loose snow together. The word "sinter" comes from the German sinter, a derivative of English "cinder". |
Siintering for iron ore is of three types
1. Circular Type 2. Walking beam Type 3. Belt Type Machines are also being known as Dwight and Lloyd machines. Dwight and
Lloyd constructed the first continuous sinter plant in 1906.Circular sinter machines are normally suitable for blast furnaces having useful volumes of 650 Cu m and less. The man parameters of some of the circular machines are given Various features of the circular machines are as below.
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Straight line machines are normally used for large sinter plants. Present straight line machines are installed having widths from 2 meters to 5 meters and with effective sintering areas from 200 to 600 Sqm. The productivity of such machines typically ranges from 30 to 46t/Sqm/day. Capacities of such machines range from 190,000 tons per annum to 6.5 Mtpa. A straight machine is shown
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Desulphurization of Hot Metal
Removal of sulphur from hot metal is called desulphurization of hot metal. Sulphur is a desirable element in steel when good machinability is required from the steel product. However it is an unwanted element in most of the applications of steel due to the following reasons.
Removal of sulphur from hot metal is called desulphurization of hot metal. Sulphur is a desirable element in steel when good machinability is required from the steel product. However it is an unwanted element in most of the applications of steel due to the following reasons.
- Sulphur affects both internal and surface quality of steel
- Sulphur contributes to the steel brittleness and when it exists in sulphide phase it acts as a stress raiser in steel products.
- It forms undesirable sulphides which promotes granular weakness and cracks in steel during solidification.
- It has adverse effect on the mechanical properties.
- It lowers the melting point and intergranular strength and cohesion of steel.