Bazuru Sludge from wet scrubbers requires an extra drying step. Blowing continues for a predetermined time based on the metallic charge chemistry and the melt specification. While this represents the loss of a considerable amount of energy about 0. The sulfur level from the blast ixigeno can be 0. Obviously the chemical analysis of obsolete scrap is imprecise.
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The inability of the Bessemer process to melt significant quantities of scrap became an economic handicap as steel scrap accumulated. It oxidizes the carbon and silicon contained in the hot metal liberating great quantities of vasico which melts the scrap. It was blown through tuyeres in the bottom of the pear shaped vessel. Therefore, hot metal was produced by remelting pig iron in cupolas and gravity feeding it to the 5 ton Bessemer vessels.
Many steel mills have agreements with manufacturers to buy their prompt scrap. BOF heat sizes in the U. The trend today is to run at high productivity with low slag volumes and fuel rates, leading to lower silicon and higher sulfur levels in the hot metal.
As blowing begins, an ear-piercing shriek is heard. This is soon muffled as silicon from the hot metal is oxidized forming silica, SiO 2which reacts with the basic fluxes to form a gassy molten slag that envelops the lance. Byit exceeded that of the open hearth for the first time and has never relinquished its position as the dominant steelmaking process in the U.
Although all refractory materials are dissolved by FeO, MgO forms a solid solution with FeO, meaning they coexist as solids within a certain temperature range. Following pilot plant trials at Linz and Donawitz, a top blown pneumatic process for a 35 ton vessel using pure oxygen was commercialized by Voest at Linz in Basic refers to the magnesia MgO refractory lining which wears through contact with hot, basic slags. The result has been that melt shop process and finishing mill quality and yields improved several percent, such that the quantity of raw steel required per ton of product decreased significantly.
Ultimately, the cost per ton of steel for brick and gunning repair materials, coupled with the need for vessel availability, dictate the choice of lining. Blowing continues for a predetermined time based on the metallic charge chemistry and the melt specification. S for scarfing, and welding. However, elsewhere its use is growing. Most BOF shops in the U. These slags are required to remove phosphorus and sulfur from the molten charge.
In the late s, Professor Durrer in Switzerland pursued his prewar idea of injecting pure oxygen through the top of the vessel. A lump of hasico burned lime dissolves quickly in a cup of water liberating heat. Fluxes serve two important purposes.
The basis for most refractory bricks for oxygen steelmaking vessels in the U. Very large pieces of scrap can be difficult to melt and may damage the vessel when charged. After the war, the Germans were denied the right to manufacture tonnage oxygen, but oxygen plants were shipped to other countries. Bessemer production peaked in the U.
In addition, the necessity of taking shops out of service to make basicco changes is not practical. A ton BOF today needs about 20 tons of pure oxygen every 40 minutes. Some dimensions of a typical ton BOF vessel in the U.
The nearby Dolomite Mountains also provided an ideal source of material for basic refractories. He developed basic linings produced from tar-bonded dolomite bricks. Scrap also comes in many sizes, varying chemical analyses and a variety of prices. Related Posts.
HORNO BASICO DE OXIGENO BOF PDF
For his first commercial plant in Sheffield,Bessemer remelted cold pig iron imported from Sweden as the raw material for his hot metal. Once the hot metal temperature and chemical analaysis of the blast furnace hot metal are known, a computer charge models determine the optimum proportions of scrap and hot metal, flux additions, lance height and oxygen blowing time. Sludge from wet scrubbers requires an extra drying step. Bf additives are available to reduce the iron oxide level in the slag but nothing can be done to alter the phosphorus. A ladle full of hot metal is seen to the right.
Horno básico de oxígeno (BOF)
In addition, as the tar softened during vessel heat-up, the lining was relieved of expansive stresses. While this represents the loss of a considerable amount of energy about 0. Scrap also comes in many sizes, varying chemical analyses and a variety of prices. The rate of gas evolution is many times the volume of the vessel and it is common to see slag slopping over the lip of the vessel, especially borno the slag is too viscous.
HORNO BOF (Horno Basico de Oxigeno)
El Proceso Primeramente se le agrega al convertidor la chatarra que se encuentra en cajas previamente pesadas. Llenar el horno con los ingredientes se llama carga. Cerca del final del ciclo de soplado, que tiene sobre 20 minutos, la temperatura se mide y se toman muestras. Tocando de acero a partir de BOF: 1. Este proceso se llama tocando el acero. La carga de este convertidor es de tonelada y media.