Cold blast
Encyclopedia
Cold blast, in ironmaking, refers to a furnace where air is not preheated before being blown into the furnace. This represents the earliest stage in the development of ironmaking. Until the 1820s, the use of cold air was thought to be preferable to hot air for the production of high-quality iron; this effect was due to the reduced moisture in cool winter air.

The discovery by James Beaumont Neilson in about 1825 of the beneficial effects of the hot blast
Hot blast
Hot blast refers to the preheating of air blown into a blast furnace or other metallurgical process. This has the result of considerably reducing the fuel consumed in the process...

 led to the rapid obsolescence of cold blast ironworks in Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

, where hot blast was in general use by 1835. Cold blast ironworks survived longer in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, but the use of hot blast as a method of smelting iron with anthracite was introduced in 1836, and the increasing US production of coke
Coke (fuel)
Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is man-made.- History :...

 gradually drove out the cold blast furnaces. However, one the last known operating cold blast charcoal
Charcoal
Charcoal is the dark grey residue consisting of carbon, and any remaining ash, obtained by removing water and other volatile constituents from animal and vegetation substances. Charcoal is usually produced by slow pyrolysis, the heating of wood or other substances in the absence of oxygen...

 furnaces, Pleasant (formerly Eagle) Furnace, in Curtin, Pennsylvania did not close until 1921.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK