Key data
| Stowage factor | 0.85–1.05 m³/t (typical 0.95)30.0–37.1 ft³/t (typical 33.5) |
|---|---|
| Form | Bulk |
| IMSBC group | C Cargoes that neither liquefy nor carry a chemical hazard. |
| Angle of repose | ~30 |
| BCSN | SUPERPHOSPHATE |
ft³/t values are per metric tonne (1 m³/t ≈ 35.31 ft³/t). Stowage factors are indicative — see note below.
Description
Triple superphosphate, or TSP, is a concentrated granular phosphate fertiliser shipped in bulk. At around 0.95 m3/t it is a deadweight cargo. It handles as a free-flowing granular product, with its concerns centring on moisture, caking and a mild acidity that can affect steelwork.
Stowage & loading
Holds are presented clean and dry, and the granules are loaded by conveyor or grab and trimmed level. Keeping the cargo dry is the priority, as TSP is hygroscopic and cakes when damp, and steelwork and bilges are noted given its mildly acidic, corrosive nature when wet.
Hazards & handling
TSP is hygroscopic and cakes or sets if it absorbs moisture, hampering discharge, and when damp it is mildly acidic and corrosive to steel and can give off faint acidic fumes. Spaces are ventilated and contact with steelwork limited, with dust a further nuisance in handling.
Carriage & discharge
The cargo is kept dry and ventilated to limit moisture pickup, caking and fume build-up, with the stow monitored. Discharge is by grab, with caked material broken out, and holds and bilges washed down afterwards to remove the corrosive residue and protect the steel.
Key hazards
- Caking and setting if the cargo absorbs moisture
- Mild acidity, corrosivity to steel and faint acidic fumes when damp
- Nuisance dust during handling
Loading precautions
- Present clean, dry holds and keep the cargo dry
- Protect steelwork and bilges against mild corrosion and ventilate spaces
- Trim level and control dust during handling
Stowage factors are indicative and vary with grade, origin, moisture and packing. Always verify against the shipper's cargo declaration and the applicable IMSBC Code schedule before fixing or loading. This is general information, not professional or safety advice.