Furnaces in Primary Metal Production

Primary metals are metals extracted from minerals that are free from scrap. NAICS (North American Industry Classification System) defines the primary metal sector as: a sector of the manufacturing industry which deals with the smelting and/or refining of ferrous/non-ferrous metals from ores; employing various metallurgical processes and techniques. The metallurgical processes used to produce primary metals involve various chemical reactions at high temperatures, which are carried out using a variety of furnaces.

Below are a few of the furnaces used for primary metal production:

1. Shaft Furnace : “Fuel and ore are continuously supplied through the top of the furnace, while air (sometimes with oxygen enrichment) is blown into the bottom of the chamber, so that the chemical reactions take place throughout the furnace as the material moves downward.” (wikipedia.org)

2. Muffle Furnace : Used in processes whose feed is sensitive to direct interaction with the fuel, so the subject material is isolated from the gases, air, and fly ash.

3. Hearth Furnaces : A furnace used where high temperatures are need and where direct heating is admissible. Reverberatory furnaces and rotary kilns are the best example of hearth furnaces.

4. Hearth Roasters : typically, 6-12 hearths are arranged vertically to roast coarse ores. Most of the roasting occurs as the particles drop from one hearth to the next.

5. Flash smelting is another process often used in the primary metal production, due to the rapid reaction rate, and thus, the excellent efficiency. Flash smelting is used with only fine particulate matter.

These are only a few of the furnaces and processes used for primary metal production. However, you can see that they all use gas and air to produce the chemical reaction needed for the desired end product. In addition, the final output from the majority of primary metal manufacturing processes is typically a formed ingot which is later processed into wire, sheet, rod, strip, ect.

All images are credited to unique source: http://www.chem.mtu.edu/chem_eng/faculty/kawatra/CM2200_Primary_Metals.pdf

For more information, please visit www.stelterbrinck.com or call Stelter & Brinck at 513-367-9300

Keywords: Primary Metal Manufacturing, Stelter & Brinck, air and gas, shaft furnace, muffle furnace, hearth furnace, electric furnace, hearth roaster, flash smelting.