Search results
Results from the WOW.Com Content Network
Blast furnaces differ from bloomeries and reverberatory furnaces in that in a blast furnace, flue gas is in direct contact with the ore and iron, allowing carbon monoxide to diffuse into the ore and reduce the iron oxide. The blast furnace operates as a countercurrent exchange process whereas a bloomery does not.
The PCI method is based on the simple concept of primary air (termed the "conveying gas") carrying pulverized coal which injected through a lance to the tuyere (mid-bottom inlet of a blast furnace), then mixed with secondary hot air (termed the "blast") supplied through a blowpipe in the tuyere and then piped to a furnace to create a balloon ...
The hot blast pumps hot air into the blast furnace. The hot blast temperature ranges from 900 to 1,300 °C (1,650 to 2,370 °F) depending on the design and condition. Oil, tar , natural gas, powdered coal and oxygen can be injected to combine with the coke to release additional energy and increase the percentage of reducing gases present ...
Molten pig iron (sometimes referred to as "hot metal") from a blast furnace is poured into a large refractory-lined container called a ladle. The metal in the ladle is sent directly for basic oxygen steelmaking or to a pretreatment stage where sulfur, silicon, and phosphorus are removed before charging the hot metal into the converter.
As of 2024, the largest steel mill in the world that still produces steel using open-hearth furnaces is the Zaporizhstal steel mill in central Ukraine, which has seven 500-ton capacity OHFs and one twin-hearth furnace as well as four blast furnaces. The availability of cheap fuel oil in large quantities, as well as the ongoing invasion, largely ...
During the Han dynasty (202 BC – 220 AD), most, if not all, iron smelted in the blast furnace was remelted in a cupola furnace; it was designed so that a cold blast injected at the bottom traveled through tuyere pipes across the top where the charge (i.e. of charcoal and scrap or pig iron) was dumped, the air becoming a hot blast before ...
The Chinese are thought to have skipped the bloomery process completely, starting with the blast furnace and the finery forge to produce wrought iron; by the fifth century BC, metalworkers in the southern state of Wu had invented the blast furnace and the means to both cast iron and to decarburize the carbon-rich pig iron produced in a blast ...
Blast furnace gas (BFG) [1] is a by-product of blast furnaces that is generated when the iron ore is reduced with coke to metallic iron. It has a very low heating value , about 3.5 MJ/m 3 (93 BTU /cu.ft), [ 2 ] because it consists of about 51 vol% nitrogen and 22 vol% carbon dioxide , which are not flammable.