I have worked in steel and in lime. Typically, the steel mill will want lower sulfur lime. Reheat kilns and shaft kilns tend to capture the sulfur in the stone which results in higher sulfur lime. Traditional "long kilns" make lower sulfur lime and have been preferred for steel shops. Some mills pay a premium for the lime from long kilns. The trade off is that long kilns are the least energy efficient, because the exit gas leaves the system at a higher temperature (over 1000F) Shaft kilns would be the most efficient, due to the ability to insulate them much more than with a rotating shell. All kilns are subject to the economy of scale, so be sure to check your economics carefully. It may indeed be cheaper in the long run to purchase from a local source if one exists.

Hugh Crosmun

Carmeuse Lime

River Rouge, Michigan, USA ■