Overview
Phosphogypsum is a calcium sulfate by-product generated during the production of phosphoric acid from phosphate rock. Depending on its origin and treatment, it can contain calcium, sulfur and a range of minor constituents carried over from the phosphate ore and process conditions. Material supplied by Bisley International is offered as an industrial raw material that may be considered for agricultural use in regions where such use is permitted by local regulations.
In some agricultural systems, phosphogypsum is evaluated as a soil amendment and as a potential source of calcium and sulfur. It may be considered for use in programs aimed at improving soil physical conditions or supplying calcium and sulfur where agronomically justified. However, the composition of phosphogypsum, including trace elements and naturally occurring radionuclides, is highly dependent on the phosphate rock and process used. Regulatory frameworks and environmental guidelines in many jurisdictions strictly govern if and how phosphogypsum can be used on agricultural land.
For this reason, any decision to use phosphogypsum in agriculture must be based on a detailed assessment by the customer's own technical, environmental and regulatory teams. Bisley International provides product documentation such as technical data sheets and safety data sheets to support this assessment, but does not define agronomic recommendations or regulatory compliance. Customers remain responsible for ensuring that any use of phosphogypsum is safe, compliant and appropriate for the intended application and region.
Applications, characteristics and considerations
Potential applications in agricultural systems
Where permitted by local regulations and supported by technical evaluation, phosphogypsum may be considered in certain agricultural applications, for example:
- Soil amendment in systems where calcium sulfate is used to improve soil structure or manage sodicity, subject to local guidelines and environmental assessments.
- Potential calcium and sulfur source in nutrient management programs where phosphogypsum meets applicable quality and regulatory criteria.
- Use in selected land reclamation or soil management projects, where specifically authorised and supported by environmental studies.
Key characteristics and composition
Phosphogypsum is distinct from natural gypsum because it is a process by-product and its characteristics depend strongly on the phosphate rock and process route. Typical aspects to consider include:
- Calcium sulfate matrix providing calcium and sulfur, with composition expressed in the technical data sheet.
- Presence of minor constituents originating from phosphate rock and process chemicals, such as trace elements and residual phosphates or fluorides.
- Potential presence of naturally occurring radionuclides associated with certain phosphate ores, which may be subject to radiological regulation.
- Physical form and moisture content, influencing handling, storage and application behaviour.
Regulatory, environmental and safety considerations
Because phosphogypsum is a by-product and can contain regulated substances, its use is often subject to specific regulatory and environmental controls. Customers should carefully consider:
- National and regional rules governing the placement of phosphogypsum on land, including radiological and environmental criteria where applicable.
- Requirements for environmental impact assessments, monitoring programs or permits before agricultural use can be authorised.
- Occupational health and safety measures specified in the safety data sheet (SDS), including dust management, personal protective equipment and storage practices.