Vernal mine phosphate ore is sedimentary rock from the Phosphoria Formation.

Simplot Phosphates continues to be the only active phosphate producer in Utah, mining the Meade Peak Member of the Permian Phosphoria Formation. The phosphate operation is located 12 miles north of Vernal in Uintah County

After research and discussions with Simplot personnel, McLanahan’s proposed a 72” (182.9 cm) wide x 45” (114.3 cm) long Apron Feeder that fed into a hybrid 48” (121.9 cm) diameter x 72” (182.9 cm) long Heavy-Duty Double Roll Crusher. This custom-engineered system incorporated the design features of a DDC-Sizer along with the drive configuration of a Heavy-Duty Double Roll, ultimately saving 465 HP to accommodate the limited power supply.

Since its start-up, the crushing station has resulted in savings in energy use and less wear and tear on the machines. The smaller, more consistent product allows Simplot to crush more ore in fewer work days.

The system crushes the phosphate ore into a more cubicle-shaped product – a consistent 8” (20.3 cm) in size. This was in contrast to the old system, which had a 10” (25.4 cm) range, but created slabs that got caught in the system, requiring shutdowns. This more consistent feed from the McLanahan crushing station to the conveyor for further processing in a sag mill has cut down on the belt trips and downtime that occurred while the slabs were removed.

Simplot has also been able to reduce the crushing schedule from 14 days to 12 days with no loss in productivity. The company uses the two days off as energy-saving days – lowering costs, slashing power usage, and saving on wear and tear.

Run of mine ore was crushed and then milled through a SAG mill and ball mill to minus 16 mesh. Milled ore was deslimed using cyclones and hydrosizers. Sands were conditioned with fatty acid, petroleum sulfonate, diesel fuel and frother prior to primary rougher and cleaner flotation. Primary flotation tailing was milled to 95 per cent minus 48 mesh, deslimed in cyclones, conditioned using reagents previously described, and then processed through rougher and cleaner scavenger flotation. Product of scavenger cleaner concentrate was upgraded by reverse flotation of dolomite. Flotation concentrates were combined and dewatered, pulp being milled to 99.5 per cent minus 65 mesh and then thickened to 65 per cent solids. Product was pumped from storage through a 10 inch, 94 mile pipeline to a conversion plant at Rock Springs, Wyoming. Mill tailing was stored behind an earthen dam, water from the settled tailing being reclaimed for mill use.

Simplot Phosphates, at their Vernal Mine Mil ........