Calcined phosphate rock

Calcined phosphate rock (CAS 65996-94-3), also known commercially as Phospal and Calciphos, is a thermally processed mineral used as a slow-release phosphorus source and soil pH corrective in agricultural markets.

The calcination process converts raw phosphorite into a more reactive form, improving phosphorus availability to crops without the rapid leaching associated with soluble fertilizers.

In crop nutrition programs, it functions as a direct-application phosphate fertilizer for acidic soils, supplying phosphorus and calcium over extended growing cycles for various crops.

Animal feed manufacturers incorporate it as a mineral supplement to meet phosphorus and calcium requirements in livestock and poultry diets, ensuring proper bone development and health.

Water treatment operations use it in pH adjustment and phosphate dosing applications, particularly where controlled, gradual release is preferred over soluble phosphate salts in the system.

It also serves as a raw material input for downstream phosphate chemical production where a calcined, low-organic mineral source is specified for high-purity industrial manufacturing processes.

Calcined phosphate rock is supplied as a fine to medium powder, with particle size typically tailored to application requirements. Feed-grade and fertilizer-grade specifications are the most commonly traded forms.

P2O5 content and heavy metal limits define grade boundaries for procurement. Technical-grade material is available for industrial and water treatment procurement to meet specific operational needs.