Process
Large walking draglines, operating twenty-four hours a day in surface mines, excavate raw pebble phosphate mixed with clay and sand (known as matrix). The matrix contains a number of chemical impurities, including naturally occurring uranium at concentrations of approximately 100 ppm.
The matrix is then dropped into a pit where it is mixed with water to create a slurry, which is then pumped through miles of large steel pipes to washing plants. These plants crush, sift, and separate the phosphate from the sand, clay, and other materials, and mix in more water to create a granular rock termed wetrock. The wetrock, which is typically of little use in raw form, is then moved largely by rail to fertilizer plants where it is processed. The final products include, but are not limited to, diammonium phosphate (DAP), monoammonium phosphate (MAP) and triple superphosphate (TSP).
Waste byproducts are stored in large phosphogypsum stacks and settling ponds, often hundreds of acres in size, and up to 200 feet (60.96 m) tall. Phosphate processing produces significant amounts of fluorine gas, which must be treated by filtering through special scrubbers.
Much of the final product (known within the industry as 'dryrock') is transported by rail to facilities along Tampa Bay, where they are transloaded onto ships destined for countries such as China.
Phosphate product intended for domestic use is assembled into long trains of covered hopper cars for northbound movement.
Read more about this topic: Bone Valley
Famous quotes containing the word process:
“It haunts me, the passage of time. I think time is a merciless thing. I think life is a process of burning oneself out and time is the fire that burns you. But I think the spirit of man is a good adversary.”
—Tennessee Williams (1914–1983)
“If thinking is like perceiving, it must be either a process in which the soul is acted upon by what is capable of being thought, or a process different from but analogous to that. The thinking part of the soul must therefore be, while impassable, capable of receiving the form of an object; that is, must be potentially identical in character with its object without being the object. Mind must be related to what is thinkable, as sense is to what is sensible.”
—Aristotle (384–322 B.C.)
“That which endures is not one or another association of living forms, but the process of which the cosmos is the product, and of which these are among the transitory expressions.”
—Thomas Henry Huxley (1825–95)