Mobile Placer Plant (MPP)

The Mobile Placer Plant is a self-contained, trailer-mounted alluvial processing system designed for traditional placer deposits consisting primarily of sand, gravel, and stone. Unlike the MSTP, the MPP uses a compact vibrating wet screen deck rather than a dedicated scrubber trommel, making it lighter, easier to relocate, and well suited for clean, free-washing material with limited clay. In the field, head ore is loaded directly into the wet vibrating feed hopper using an excavator, backhoe, or front-end loader. Water is introduced as the material passes across the vibrating scalping screen, where the ore is washed and classified. Oversize material is discharged from the rear of the plant, while the classified gold-bearing slurry gravity-feeds the onboard Low-G Horizontal Centrifuge for primary recovery. The complete plant is mounted on a towable multi-axle trailer and includes an onboard CAT-powered hydraulic system, water pump, control panel, recovery equipment, and leveling jacks. Because material moves from the screen deck to the centrifuge by gravity, the MPP requires no additional feed conveyors between classification and recovery and can operate continuously throughout the production shift. MPP plants are available in capacities from 25 to 100 cubic yards per hour. The compact MPP-25 can generally be operated with a single excavator or backhoe, while larger models typically use an excavator for digging and a wheel loader for feeding and tending the plant. At the end of the shift, the primary concentrate is discharged from the centrifuge and can be processed through a Reverse Multi-Helix Spiral Cleaner or Finisher to produce a reduced-volume, high-grade final concentrate. The MPP is best suited for low-clay placer material. Because the vibrating screen provides limited scrubbing and retention time, the MPP is not recommended for ores containing more than approximately 25% clay. Clay-rich deposits generally require the increased agitation and washing action of the Mobile Scrubber Trommel Plant.