Blast furnace walls

In 1971, Konig related the corrosion rate of refractories in the bosh area of blast furnace walls to the temperature gradient in the wall. This analysis... 

The prime requirement of any carbonaceous material used in the blast furnace hearth wall or bottom is to contain Hquid iron and slag safely within the cmcible, throughout extended periods of continuous operation, often up to 15 years. 

Vorder-teil, to. front part, front, -wand, /. front wall, front, (of a blast furnace) breast, -wtirze, /. first wort. 

The effect of a liquid can for instance be seen in a glass oven. The glass melt is acid and consequently the oven wall should not contain any alkaline bricks or the coating will dissolve. Solids cause mechanical damage. In a blast furnace, for instance, a mixture of ore and cokes moves along the bricks. Only bricks with hard, well-sintered grains can withstand this. 

Reverberatory furnaces3 are particularly suitable for fines and flue-dust from the blast-furnaces. Their walls and roof are lined with silica bricks, and the hearth with silica sand. A typical charge consists of2 ... 

For steam boilers, fuels are natural gas and blast furnace gas. A large number of small burners (about 30 hp. each) is used for the former. Burners are thoroughly distributed. As with fuel oil, they may be directed either slightly downward toward the rear or may face from the bridge wall toward the front. The combustion space should be large. The air supply is drawn in around the gas jet. High eflSciency is easily possible. For blast furnace gas, use a furnace space of 2 cu. ft. per rated horsepower, 0.8 sq. in. of gas passage area per horsepower and 2 in. blast (based on 6 to 8 in. pressure in main). Provision must be made for removal of dust. With all gas burners, the gas and air supply should be separately controllable. 

Figure 2.6 Chloride profiles of a quay wall on vidual results of four cores (only symbols) the Dutch North Sea coast after 8 y of splash and best fitting profile according to zone exposure, blast furnace slag cement Eq. (4). described by = 1.77%, average of measured profiles (thin line), indi- D pp = 0.89 X 10rff/s...

Calculation of the heat balance results in the stated heat transfer efficiencies. The cold blast cupola shows an efficiency of <30 %. The application of oxygen or secondary air increases the efficiency to 37 - 40 %. The hot blast cupola shows a further increased efficiency, providing the furnace wall is refractory lined. In liningless operation, the efficiency drops below 40 %, which may be somewhat compensated for by adding oxygen. The cokeless cupola with inductive superheating results in a very high efficiency, close to 60 %. 

Slag Notch. The hole in the refractory brickwork of the wall of the hearth of a blast furnace permitting molten slag to flow from the furnace as and when necessary. It is also sometimes known as the CINDER NOTCH. 

Taphole. A small passage through the refractory lining of the hearth-wall of a metallurgical furnace, e.g. a blast furnace or open-hearth steel furnace. 

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