Urea is the largest single nitrogen fertilizer seaborne cargo, with global seaborne trade of approximately 50 to 55 million tonnes per year. The cargo is principally moved from major producing regions (Russia, China, the Middle East, North Africa) to agricultural markets globally, with the largest importers being India, Brazil, the United States, and various Sub-Saharan African nations. The IMSBC Code regulates urea shipments under a Group C schedule with handling requirements driven principally by hygroscopic caking and dust generation.
Schedule structure
The IMSBC Code includes the following urea-related schedule entries:
- Urea: bulk granulated, prilled, or pelletised urea. Group C (not liquefiable, no chemical hazard).
- Urea solution (UN 9 or various): liquid urea, separate IMDG handling.
Most marine urea trade is granular or prilled solid urea handled under the Group C bulk schedule.
Cargo properties
Urea (CO(NH2)2) is supplied in two principal commercial solid forms:
- Prilled urea: small spherical pellets of approximately 1 to 3 millimetres diameter formed by spraying molten urea into a cooling tower. Lower handling characteristics than granular but still widely produced.
- Granular urea: harder granules of approximately 2 to 4 millimetres diameter formed by drum or fluid bed granulation. The dominant modern commercial form due to better handling and storage characteristics.
Bulk density is approximately 0.7 to 0.78 tonnes per cubic metre, with stowage factor of approximately 1.3 to 1.4 cubic metres per tonne. The cargo is non-toxic, non-flammable, and non-self-heating.
Cargo handling concerns
The principal handling concerns for urea are:
- Hygroscopic caking: urea is highly hygroscopic and absorbs moisture from humid air, forming hard cakes that resist discharge. Holds must be weather-tight, hatch covers must be intact, and humidity should be minimised throughout voyage. Caked urea is difficult to discharge and may require mechanical breakage.
- Compatibility with steel: urea is mildly corrosive to steel, particularly in the presence of moisture and elevated temperature. Hold paint coatings should be intact.
- Dust generation: urea generates moderate dust during handling, particularly the prilled form. Dust suppression is required at major terminals.
- Compatibility with other cargoes: urea must not be loaded adjacent to oxidising fertilizers (ammonium nitrate, calcium nitrate) due to incompatibility. Inter-cargo segregation is required where holds carry mixed shipments.
Major routes
Urea seaborne trade flows include:
- Russia to global markets: significant export through Saint Petersburg and Black Sea ports, subject to sanctions complications since 2022.
- Middle East (Saudi Arabia, Qatar, UAE, Iran, Oman) to global markets: large gas-based urea export from Persian Gulf production.
- China to selected markets: variable exporter depending on domestic policy.
- Egypt and North Africa to global markets: Mediterranean export from gas-based production.
- United States to Latin America: Gulf Coast export.
India is the largest single urea importer globally, accounting for approximately 25 to 30 per cent of global trade, with imports principally from Middle Eastern and Russian producers.
Loading and discharge
Loading is by shore conveyor and shiploader at major export terminals. Loading rates of 1,500 to 4,000 tonnes per hour are typical. Hold preparation requires complete dryness and weather-tightness.
Discharge is by grab-fitted shore cranes or pneumatic unloaders at receiving fertilizer-distribution terminals.
See also
- Ammonium Nitrate Fertilizer: IMSBC Code Schedule and Carriage
- Phosphate Rock: IMSBC Code Schedule and Carriage
- Potash: IMSBC Code Schedule and Carriage
Additional calculators:
- IMSBC Group A/B/C Classification
- IMSBC Angle of Repose
- Bulk Sulphur - Dust Explosion Risk
- IGC \u2014 Nitrogen (liquefied)
Additional related wiki articles: