Phosphogypsum is the primary waste byproduct of the wet-acid process for producing phosphoric acid. The wastes of most concern are the byproducts created during the wet and thermal processing steps of fertilizer production. also has a phosphate industry, particularly in Idaho. Florida alone accounts for approximately 80 percent of the current capacity, making it the world’s largest phosphate producing area. About 90 percent of domestic production capacity in Florida, North Carolina, and Tennessee. The phosphate industry is concentrated in the southeastern U.S. Most phosphate production leads to the making of fertilizers. was estimated at 23 million metric tons (MT). In 2019 the total production of phosphate rock in the U.S. Phosphate rock (phosphorite) mining is the fifth largest mining industry in the United States in terms of quantity of material mined. (but without data on radionuclide content) can be found on the Department of Agriculture's website. Further data on fertilizer consumption in the U.S. Fertilizers are available in over 100 different blends with varying concentrations of nitrogen, phosphorus and potassium. A typical phosphate fertilizer application rate is about 40 kg per hectare (approximately 15 lbs. The concentration of Ra-226 varies from approximately 0.185 - 1.11 Bq/g (5 - 30 pCi/g), depending upon the type of fertilizer blend and the origin of the phosphate rock.įertilizer application rates vary depending upon the type of crops and soils. While phosphate fertilizers are not considered to be waste, they do contain some of the naturally occurring radium (Ra-226) found in phosphate ores. averaged close to 5.8 million metric tons (MT) between 19, and had increased to over 8.5 million MT by 2007. The yearly consumption of phosphate-based fertilizers in the U.S. The United States mines and consumes about 23 million tons of phosphate rock per year, most of it (95%) for wet-process phosphoric acid or super phosphoric acid with the balance used to produce phosphorus compounds for industrial applications, primarily glyphosate herbicide. This processing concentrates NORM in the waste products, transforming them into Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM). Thorium occurs at essentially background levels, between 1 - 5 ppm (or about 0.0037 0.022 Bq/g, which is 0.1 - 0.6 pCi/g).īefore phosphate ore is turned into fertilizer or other products, it is transformed into either phosphoric acid (through a wet process), or elemental phosphorus (through a thermal process). range from 20 - 300 parts per million (ppm) (or ~0.26 - 3.7 becquerels per gram (Bq/g), which is 7 - 100 picocuries per gram (pCi/g)). Uranium concentrations in phosphate ores found in the U.S.
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