Reverberatory Furnace - Applications and Comparison With Blast Furnace

Applications and Comparison With Blast Furnace

The applications of these devices fall into two general categories, metallurgical melting furnaces, and lower temperature processing furnaces typically used for metallic ores and other minerals.

A reverberatory furnace is at a disadvantage from the standpoint of efficiency compared to a blast furnace due to the spatial separation of the burning fuel and the subject material, and it is necessary to effectively utilize both reflected radiant heat and direct contact with the exhaust gases (convection) to maximize heat transfer. Historically these furnaces have used solid fuel, and bituminous coal has proven to be the best choice. The brightly visible flames (due to the substantial volatile component) give more radiant heat transfer than anthracite coal or charcoal.

Contact with the products of combustion, which may add undesirable elements to the subject material, is used to advantage in some processes. Control of the fuel/air balance can alter the exhaust gas chemistry toward either an oxidizing or a reducing mixture, and thus alter the chemistry of the material being processed. For example cast iron can be puddled in an oxidizing atmosphere to convert it to the lower-carbon mild steel or bar iron.

Reverberatory furnaces (in this context, usually called air furnaces) were formerly also used for melting brass, bronze, and pig iron for foundry work.