Method for processing colemanite ore

Abstract

Abstract In the method, a hot gas is flowed linearly through a slightly inclined treating area. Colemanite ore particles are repeatedly elevated and dropped substantially vertically through the gas while they are simultaneously advanced countercurrent to the gas flow. This movement is continued until the ore particles are heated to the point of decrepitation at which they relatively suddenly break into a large number of relatively fine particles of substantially sure colemanite which are carried out of the treating area by the gas stream. The gas carried colemanite particles are then separated from the gas stream to provide an upgraded and classified product. Gas velocity and temperature and the path and rate of movement of the ore through the gas are varied as required to obtain a given grade or size in the recovered colemanite product. The apparatus used in practicing the method includes, in a preferred form, a tubular calcining drum which is inclined slightly with respect to the horizontal. Lifters are positioned along the internal wall of the calcining drum and the drum is rotated between two stationary end assemblies. Ore particles are introduced into the upper end of the drum and a stream of hot gas is introduced through the lower end of the drum. Rotation of the drum causes the ore to be repeatedly lifted and dropped across the gas stream while the ore simultaneously advances from the upper toward the lower end of the drum. The temperature of the advancing ore increases to the point required to cause decrepitation of the ore, and the gas stream flowing through the drum carries the particles of decrepitation to the upper end of the drum where they are removed and separated from the gas stream. In the preferred form, gas leaving the drum is conveyed to a second rotating, inclined drum which functions as a preheater for ore being introduced into the calcining drum.

Inventors

• 👤 David Wilson
• 👤 Blair T Burwell

Bibliographic Details