Masonry Magazine October 1962 Page. 15
Vermiculite
(Continued from page 13)
The mill blends material from various parts of the deposit to ensure uniformity. The blend is fed through a series of crushers, screens, and water flotation to remove rock and other foreign matter. It is dried in large rotary kilns and screened into six graded sizes for various end uses. The entire process is controlled by numerous automatic interlocking systems. Assayers are on duty 24 hours a day to test samples. The Libby operation includes a pilot expansion plant, where new furnace models and improvements are checked out.
Ore concentrate is trucked from the mill to large bins at the railroad siding. From these it is automatically weighed and fed into box cars for shipment by rail to about 40 expanding plants throughout the United States and Canada.
At the plant, the concentrate is unloaded with power shovels or scoops and is stored in bins or silos. From there it goes to an elevator that takes it to the expanding furnace. The one most widely used is a modified vertical furnace heated by oil or gas-fired burners to a temperature of about 2000° F.
The concentrate is fed into the top of the furnace and cascades to the bottom. It falls first on staggered baffle plates, then directly through the flames, expanding as it falls. A bucket elevator below carries the expanded material to an air lift which removes rock particles, cools the product, and elevates it for further processing. It is classified according to the particle size by gyratory screens or by air classifiers. From there the material goes to a bagging hopper and is packaged in multi-wall paper bags containing four cubic feet.
25 MASONS
three floors up
easily supplied
by
LAD-E-VATOR
Automatic
Hoist!
... a positive answer to the problem of rising costs and a larger PROFIT for you.
The Lad-E-Vator is built of tempered aluminum, giving an overall weight only one-third that of steel. Because of this light weight the Lad-E-Vator transports and sets-up easily. The tower telescopes to 16, 20 or 25 ft. lengths for towing behind car or truck. Unloading height for materials up to 42 ft. Load capacity is 1250 lbs. Lad-E-Vator is also available with a curved top for using as a skip, or with dumping scoop for hoisting loose materials.
Write us today for the distributor nearest you.
CAMPBELL Equipment Company
P. O. Box 306, Des Plaines, Illinois
vermiculite granules emerging from the bottom of a vertical shaft, gas-fired furnace.
RY • October, 1962
15