Rotating Furnaces

Rotating furnaces consist of a refractory-lined cylinder that rotates slowly around a horizontal axis. The charge is heated directly from an open flame, typically fed by either gas or oil. Exhaust gases are extracted from the opposite end of the chamber. Rotating the furnace helps to mix the charge and utilises heat from the whole refractory surface.

Immediately after melting, the melt is covered with a layer of salt. This reduces slag formation by protecting the melt from oxidisation. Rotating melting furnaces are relatively inefficient, at around 990-1080 kW.h/tonne of metal melted, but the lower cost of fuel offsets this disadvantage to some extent.