Blast furnace stove

Specific Heat. In some appHcations refractories are used for heat-exchange purposes on the regenerative principle, for instance, in blast-furnace stoves. High heat capacity is requited in such appHcations (Table 8). 

The carbonization by-products are usually refined, within the coke plant, into commodity chemicals such as elemental sulfur (qv), ammonium sulfate, benzene, toluene, xylene, and naphthalene (qv) (see also Ammonium compounds BTX processing). Subsequent processing of these chemicals produces a host of other chemicals and materials. The COG is a valuable heating fuel used mainly within steel (qv) plants for such purposes as firing blast furnace stoves, soaking furnaces for semifinished steel, annealing furnaces, and lime kilns as well as heating the coke ovens themselves. 

Blast-Furnace Stoves Blast-furnace stoves are used to preheat the air that is blown into a blast furnace. A typical blast furnace, producing 1500 Mg (1650 U.S. ton) of pig iron per day, will be blown with 47.2 mVs (100,000 std ft /min) of atmospheric air preheated to temperatures ranging in normal practice from 755 to 922 K (900 to 1200°F). A set offour stoves is usually provided, each consisting of a vertical steel cylinder 7.3 m (24 ft) in diameter, 33 m (108 ft) nigh, topped with a spherical dome. Characteristic plan and elevation sections of a stove are shown in Fig. 24-61. The interior comprises three regions in the cylindrical portion, (1) a side combustion chamber. 

Fig. 10. Blast furnace stove for preheating large quantities of air...

Use Heating blast-furnace stoves, boilers, or as a gas-engine fuel. 

The same principle applies to blast furnace stoves and to the multiple-tower heat recovery units positioned around the periphery of vertical cylindrical incinerators for waste gases or liquids. For furnaces with lower temperature waste gases, such as boilers or steam generators, a Ljungstrom all-metal recuperator, rotating on a vertical shaft, is used. 

The blast furnace stove, which heats the air that will be blown into the furnace from the tuyeres and burns the coke, is insulated with an acid-resistant gurmed material. The stack section is also lined with a gunned castable. A high-alumina monolithic refractory is used around the spout of the torpedo ladle. Torpedo ladles are used for transferring molten iron from the iron-making section of the plant to the steel section. Often when shortterm repairs are done to this item, monolithic refractories are used. 

FHgh-alumina refractories Blast furnace stoves, cement and lime rotary kilns, electric arc furnace roofs, ladle, glassmaking furnaces, etc. 

The most used refractory lined vessel geometry in industry appears to be the cylindrical refractory lined vessel. In the steel industry, the blast furnace, blast furnace stoves, torpedo cars, steelmaking ladles (7), electric arc furnaces, degasser vessels, and cyclone dust collector are a few examples of cylindrical vessels. In the petrochemical industry, the petrochemical processing vessels are typically cylindrical. Fluid bed reactor vessel walls are typically cylindrical with a spherical vessel top. Many other basic industries use cylindrical refractory lined vessels such as rotary kilns and wood pulp process vessels. 

Other examples of cylindrical lined vessels include blast furnaces, blast furnace stoves, basic oxygen furnaces, torpedo ladles, shaft kilns, multiple hearth furnaces, and rotary kilns. Some refractory lined vessels have refractory lined conical bottoms. When heated, the conical lining will want to displace upward. Therefore, the top mortar joint of the conical lining is critical. The cylindrical lining will be critical in restraining the upward expansion of the conical lining. At the ends of rotary kilns, restraint must be provided to contain and keep the kiln lining within the kiln shell. 

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