Method of and apparatus for drying particulate minerals for agglomeration

Claim 1

Apparatus for reducing the moisture content in filter cake comprising: a. a high intensity mixer having a horizontally-extending drum with a charging opening at one end and a discharge opening at the other end, the drum having a smooth interior surface and having an axial shaft therein with radial arms arranged therealong and spaced thereabout, the arms having plows that have a working clearance with the interior of the drum, the drum having means about the exterior thereof for heating the interior walls thereof, b. feeder means for introducing material to be dried at a controlled rate into one end of the drum while excluding the free influx of outflow of air, and means adjacent the bottom oF the drum for discharging material which has been at least partially dried at a controlled rate from the other end of the drum while also preventing the free influx or outflow of air therethrough whereby controlled flow into and out of the drum may be effected, and c. the drum having means for controlling the circulation of air therethrough including an air inlet at the end of the drum into which material is charged and an outlet at the opposite end of the drum.

Claim 5

The method of removing excess water from ore concentrates and the like in the form of filter cake preparatory to agglomeration thereof comprising: a. supplying the filter cake to be processed to one end of the fixed drum of a high intensity mixer having a heated jacket thereabout and having an axially-extending driven rotatable shaft on which are a plurality of spaced mixer arms each with a plowshare thereon and withdrawing it from the other, b. circulating a heated fluid through the heating jacket surrounding the drum to maintain at least some inner areas of the drum at a temperature above the boiling point of water, c. operating the mixer in such manner that the plow-shares of the mixer arms on the shaft rotating within the drum separate small fragments from the entire mass within the drum and throw them in continuous succession against the hot interior of the drum to effect substantially instant surface drying of those particles of each fragment which contact the inner surface of the drum and the fragments upon so contacting the drum then fall away or are knocked loose by the plow-shares on the mixer arms without spreading as a film over the interior of the drum, leaving its surface exposed to contact by the next portion of the material which is hurled against it, and d. continuously removing moisture vapor and steam from the interior of the drum near the end of the drum from which the material is withdrawn.

Claim 6

The method of removing excess water from ore concentrates and the like in the form of filter cake preparatory to agglomeration thereof comprising: a. supplying the filter cake to be processed to one end of the fixed drum of a high intensity mixer having a heated jacket thereabout and having an axially-extending driven rotatable shaft on which are a plurality of spaced mixer arms each with a plowshare thereon and withdrawing it from the other, b. circulating a heated fluid through the heating jacket surrounding the drum to maintain at least some inner areas of the drum at a temperature above the boiling point of water, c. operating the mixer in such manner that the plow-shares of the mixer arms on the shaft rotating within the drum separate small fragments from the entire mass within the drum and throw them in continuous succession against the hot interior of the drum to effect substantially instant surface drying of those particles of each fragment which contact the inner surface of the drum and the fragments upon so contacting the drum then fall away or are knocked loose by the plow-shares on the mixer arms without spreading as a film over the interior of the drum, leaving its surface exposed to contact by the next portion of the material which is hurled against it, and d. continuously removing moisture vapor and steam from the interior of the drum near the end of the drum from which the material is withdrawn.