The phosphate deposits of Florida are sedimentary in origin and part of a phosphate-bearing province that extends from southern Florida north along the Atlantic coast into southern Virginia. Sedimentary phosphate deposits consist of rock in which the phosphate mineral(s) occur in grains, pellets, nodules, and as phosphate replacement of calcium in the remains of animal skeletal material and excrement.

All of Mosaic phosphate deposits are located in the Central Florida Phosphate District. The general description of the phosphatic deposits in Central Florida consist of two geological facies. The phosphate bearing units are within the Bone Valley Member of the Peace River Formation and the undifferentiated Member of the Peace River Formation within the South Florida Extension region of the Central District. The deposit characteristics transition from north east to the south west. The major phosphate bearing units in the north east consist of a productive Bone Valley Member with limited production in the Undifferentiated Member. The phosphate bearing units in the south west exhibit limited production in the Bone Valley Member and a productive Undifferentiated Member of the Peace River Formation.

The phosphate stratigraphy consists of 5 to 50 feet thick, white to brown poorly graded quartz sand with varying abundance of reworked phosphate grains as waste overburden. The economic zone is 13 to 50 feet thick, with a grade ranging from 27 to 35% P O . It consist ........

Florida phosphates is includes three phosphate production stage mining facilities (South Fort Meade, Four Corners and Wingate) and three exploration properties (DeSoto, Pioneer and South Pasture) in Florida consist of over 210,000 acres of property in Central Florida.

Phosphate is extracted using surface mining techniques. Mining utilizes either electric walking draglines or dreadges to remove overburden and mine the phosphate ore (matrix). The matrix is hydraulicaly transported to the benefication plants via a series of centrifugal pumping systems.

Mining at Four Corners and South Fort Meade are conducting via draglines.

Draglines utilize a one-pass. modified simple side-cast method for overburden removal and mining of matrix. Overburden will be spoiled on top of the ground, in an adjacent mined out cut or pumped, depending on overburden matrix thickness and available area. Geological considerations such as overburden matrix thickness, spoil stacking characteristics and dragline reach arc considered in cut design to ensure spoiled overburden does not encroach on uncovered matrix.

Regardless of the cut type and spoil placement, matrix is mined in a consistent manner. An earthen well is formed with earthmoving equipment outside of the dragline cut but within the dragline dumping radius. After the dragline uncovers an advance of approximately 50 ft. (16 m). matrix is mined and placed in the well where it is slurried with 10.000 US gp ........

Sizing Area
South Fort Meade is different from the other beneficiation plants in that it includes three stages of sizing. The raw feed (unsized feed) is pumped to a secondary declay cyclone to remove clay and the underflow feeds the primary sizer. The overflow of the primary sizer feeds the fine flotation bins while the underflow of the primary sizer feeds the secondary sizer. The overflow of the secondary sizer reports to the coarse notation bin and the underflow feeds (he tertiary sizer. The overflow of tertiary sizer reports to the ultra-coarse feed bin while the underflow is pumped to the sizer rock bin as phosphate rock product or recycles back to the washer. South Fort Meade sizing generates four materials: sizer rock, ultra-coarse flotation feed, coarse flotation feed, and fine flotation feed. The particle size is in the range of 16 to 20 mesh, 20 to 24 mesh. 24 to 35 mesh, and 35 to 150 mesh, respectively.

Four Comers has two stages of sizing. The unsized feed is pumped to a secondary' dcclay cyclone to remove clay and the cyclone underflow goes to the hydrosizer. The overflow of the hydrosizer feeds the fine flotation bins while the underflow of the hydrosizer goes to the banana screens. The underflow of the banana screens reports to coarse flotation bin and the overflow of banana screens (IP or intermediate pebble) is a phosphate rock product. The particle size of Four Comers IP. coarse flotation feed, and fine flotation feed is 16 to 24 mesh. 24 to 35 mesh, and 35 to 150 mesh, respectively.

Wingate plant has two steps of sizing primary' and secondary. The unsized feed goes to a secondary' declay cyclone to remove clay. Cyclone underflow feeds the primary sizer The overflow of primary sizer reports to the fine flotation feed bin while the underflow' is pumped to scalp screen. The overflow of scalp screen is recycled back to trommel screen underflow's tank and the underflow goes to the secondary sizer. The overflow of secondary sizer combines with primary sizer overflow and feeds the fine flotation circuits. The underflow of secondary* sizer reports to the coarse flotation feed bin. I he particle size of Wingate coarse flotation feed and fine flotation Iced is 20 to 35 mesh and 35 to 150 mesh, respectively.

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