Diammonium phosphate (DAP) and monoammonium phosphate (MAP) are major fertilizer dry bulk cargoes, with combined global seaborne trade of approximately 25 to 30 million tonnes per year. The cargoes provide both nitrogen and phosphorus nutrients in a single granular product and are major feedstocks for direct application and for bulk fertilizer blending. The IMSBC Code regulates DAP and MAP shipments under a Group C schedule.
Schedule structure
The IMSBC Code includes the following ammonium phosphate-related schedule entries:
- Diammonium phosphate (DAP): NH4)2HPO4 fertilizer with typical 18-46-0 grade (18% N, 46% P2O5). Group C (not liquefiable, no chemical hazard).
- Monoammonium phosphate (MAP): NH4H2PO4 fertilizer with typical 11-52-0 grade. Group C.
- Ammonium phosphate (general): a closely related entry covering blended grades. Group C.
These entries cover non-hazardous fertilizer cargoes handled under standard bulk procedures.
Cargo properties
DAP and MAP are supplied as granular fertilizer with particle size typically 1 to 4 millimetres diameter. Bulk density is approximately 0.9 to 1.0 tonne per cubic metre, with stowage factor of approximately 1.0 to 1.1 cubic metres per tonne. The cargo is non-toxic, non-flammable, and non-self-heating, but is hygroscopic and presents handling concerns related to moisture exposure.
Cargo handling concerns
The principal handling concerns are:
- Hygroscopic caking: DAP and MAP absorb atmospheric moisture and form hard cakes if exposed to humid conditions. Holds must be weather-tight; bilge wells must be inspected and dried; any moisture ingress can damage cargo significantly.
- Compatibility with steel: phosphate fertilizers are mildly corrosive to steel in the presence of moisture. Hold paint coatings should be intact.
- Dust generation: granular ammonium phosphates generate moderate dust during handling. Dust suppression is required at most modern terminals.
- Compatibility with other cargoes: incompatible with strong oxidisers and with chlorides (potash) when storage conditions allow chemical interaction. Standard inter-cargo segregation applies for mixed shipments.
Major exporters
DAP and MAP seaborne trade flows include:
- Saudi Arabia (Ma’aden Phosphate Company): major Middle Eastern exporter from Ras al-Khair to global markets.
- Morocco (OCP): largest African exporter from Jorf Lasfar to global markets.
- United States (Mosaic, Nutrien): Gulf Coast export.
- Russia (PhosAgro, EuroChem): Black Sea and Baltic export, subject to sanctions complications.
- China: large producer with significant export to Asian markets.
Major importers
DAP and MAP imports go principally to:
- India (largest single importer, with monsoon-driven seasonal demand).
- Brazil.
- United States (despite domestic production, regional imports for the Eastern and Pacific markets).
- Pakistan.
- Bangladesh.
Loading and discharge
Loading is by shore conveyor and shiploader at major fertilizer export terminals. Loading rates of 1,500 to 4,000 tonnes per hour are typical. Hold preparation requires dryness and weather-tightness.
Discharge is by grab-fitted shore cranes at receiving fertilizer terminals.