shaft furnace
Quick Summary
A shaft furnace is a tall, upright furnace that is loaded from the top and from which materials are removed from the bottom. In metallurgy, these furnaces are crucial for extracting metals from their ores.1
A key example is the zinc-lead blast furnace, where sintered zinc and lead concentrates are mixed with coke and charged into the top of the shaft furnace. Preheated air is blown in at the base, initiating a process similar to iron blast furnaces. However, the primary products are a zinc-bearing gas and liquid phases that separate in the hearth. The zinc vapor is then condensed and separated.2
Blast furnaces, like those used for iron, are essentially countercurrent heat and oxygen exchangers. They feature a steel shell with a refractory lining and are divided into sections: the hearth, bosh, barrel, and stack. These furnaces are vital in releasing metals like iron from their combined state with oxygen.3
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- iron processingHistory
Stone-built shaft furnaces, on the other hand, relied on natural draft, although they too sometimes used tuyeres. In both cases, smelting involved creating a bed of red-hot charcoal to which iron ore mixed with more charcoal was added. Chemical reduction of the ore then occurred, but,…
Read MoreStone-built shaft furnaces, on the other hand, relied on natural draft, although they too sometimes used tuyeres. In both cases, smelting involved creating a bed of red-hot charcoal to which iron ore mixed with more charcoal was added. Chemical reduction of the ore then occurred, but,…
Read More - iron processingPelletizing
…of firing equipment was the shaft furnace. This was followed by the grate-kiln and the traveling grate, which together account for more than 90 percent of world pellet output. In shaft furnaces the charge moves down by gravity and is heated by a counterflow of hot combustion gases, but the…
Read More…of firing equipment was the shaft furnace. This was followed by the grate-kiln and the traveling grate, which together account for more than 90 percent of world pellet output. In shaft furnaces the charge moves down by gravity and is heated by a counterflow of hot combustion gases, but the…
Read More