Phosphate Ore Processing Methods
Phosphate ore processing methods rely on raising the phosphorus pentoxide content to commercially required levels (30%-40%). Processing methods vary depending on the condition and nature of the ore. The most important methods used are:
1. Washing, drying, and then dust removal, such as those used in Egyptian ores and Christmas Island in the Indian Ocean.
2. Dry sorting, such as those used in Palestine, or wet sorting, such as those used in Togo.
3. Incineration to remove organic matter, such as those used in Jebel Onq ores in Morocco, or to remove calcium carbonate, such as those used in Akashat ores in Iraq.
4. Flotation to remove silica, such as those used in Senegal and Florida ores.
5. Magnetic separation to remove iron content, such as those used in Togo.
Uses
Phosphorus is one of the most important chemical elements for plants and animals and is involved in all vital functions. Plants obtain phosphorus from the soil, while animals obtain phosphorus from the plants they feed on. This highlights the importance of phosphate in human life. Some uses of phosphate can be reviewed as follows:
1. Fertilizer manufacturing: This represents approximately 77% of phosphate uses. Phosphate is reacted with acids to produce superphosphate, nitrogenous phosphate, and compound fertilizers. Phosphate rocks can also be ground and added directly to acidic soil. This method represents approximately 4% of phosphate uses. Superphosphate contains 14-25% phosphorus pentoxide, while nitrogenous phosphate and compound fertilizers contain 40-45% of degradable and absorbable phosphorus pentoxide.
2. Thermal phosphorus and phosphoric acid manufacturing: This industry represents approximately 8% of phosphate uses and is used in surface treatment of metals such as aluminum, copper, and nickel-coated iron, as well as in chemical detergents and pesticides.
3. Preparing phosphates as livestock feed: This industry represents approximately 6% of phosphate uses, with calcined phosphates containing a small percentage of fluorine being used in livestock feed.
4. Multiple phosphate industries: This industry represents 5% of phosphate uses and is used in industrial and household laundry detergents.