An investigation has been conducted into the factors governing the dispersion of powders smaller than 10 microns in diameter from a packed state in a small reservoir into a transport tube. The system studied consisted of a reservoir in the shape of a cylinder 5 to 10 inches long and 0.75 to 1.50-inch in diameter. Outlet tubes varied from 4 to 14 inches in length and from l/l6- to 3/l6-inch inside diameter.nThe "free-foiling terminal velocity" of the particle agglomerate was disclosed to be a critical parameter of the reservoir design. For rates below this terminal velocity the quantity of powder that remains in the res¬ervoir can be correlated with the gas velocity and reservoir dimensions by means of a simple fluidization theory.nThe influence of outlet tube dimensions upon gas quantity end pres¬sure requirements and upon rate of solids flow was determined.nThe discharge of a powder designated as "Sm" was studied. The dis¬charge could occur either as a fluidized flow or as a piston type of flow, depending upon the gas rate. From fluidization measurements it was estimated that the "Sm" consisted of agglomerates averaging 760 microns in diameter and a density of 049 grams per ml.
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