RONALD L ATWOOD
Pilots at 350, Farmington, UT

4997549, Mar 5, 1991

Sep 19, 1989

7/409385

Ronald L. Atwood - Farmington UT

Advanced Processing Technologies, Inc. - Salt Lake City UT

B03D 124, B03D 114

209164

An apparatus and method for separating hydrophilic particles from a fluid suspension containing both hydrophilic and hydrophobic particles. A generally cylindrical separation vessel includes tangential inlet and outlet ports. The fluid suspension is introduced into the separation vessel through the inlet port to circulate around the inner surface of the separation vessel in a forced vortex swirl flow. Air sparged through a porous wall portion of the side walls of the separation vessel forms air bubbles to which attach hydrophobic particles in particle/bubble aggregates. These migrate as a froth towards the axial center of the separation vessel where they are discharged at the upper end thereof. A froth washing tube having an open end proximate to the upper end of the separation vessel discharges pressurized water thereinto. A deflector located opposite the open end of the froth washing tube causes the momentum of the pressurized water discharged to be directed radially outward from the open end of the froth washing tube in a spray that passes through the froth toward the side walls of the separation vessel, removing hydrophilic particles entrained in the froth.

4923510, May 8, 1990

Sep 13, 1989

7/406839

Gopalan Ramadorai - Elko NV
Brian Ball - Salt Lake City UT
Ronald L. Atwood - Farmington UT
Sevket Acar - Salt Lake City UT

C22B 1104

423 29

Refractory carbonaceous sulfide ores are treated in a manner so as to improve gold recovery by a treatment in specific combination of steps whereby the ore is treated with chlorine after pretreatment and before cyanidation; the particular steps in the treatment of the ore have been found to be necessary as the conventional pretreatment will not improve the yields on any economic basis.