Overview
Anhydrous ammonia is pure ammonia gas compressed into liquid form under moderate pressure. It contains 82% nitrogen by weight, making it the most concentrated form of nitrogen fertiliser available. Because of this efficiency, it is a backbone input in row-crop agriculture, particularly in the United States, Brazil, and parts of Eastern Europe.
Production
Anhydrous ammonia is produced through the Haber–Bosch process, combining nitrogen (from air separation) with hydrogen (commonly derived from natural gas or coal gasification). It is the base chemical for most other nitrogen fertilisers, including urea, ammonium nitrate, and UAN solutions.
Storage & Transport
- Stored as a liquid in pressurised tanks.
- Transported in railcars, barges, or nurse tanks for farm application.
- Requires careful safety procedures due to risks of severe burns and respiratory damage on contact.
Uses
- Direct application: Knife-injected into soils pre-plant or side-dress.
- Feedstock: Basis for urea, ammonium nitrate, UAN, and nitric acid.
- Industrial: Refrigeration and various chemical intermediates.
Global Context
- USA: Heavy reliance on fall and spring application in corn belt; sensitive to natural gas prices and Mississippi River logistics.
- Brazil: Key nitrogen source, imported heavily due to limited domestic capacity.
- China: Both producer and consumer, often linked with coal-based ammonia routes.
Challenges
- Safety: High handling risk limits use outside major mechanised farming regions.
- Environmental: Volatilisation and leaching if not incorporated quickly into soil.
- Regulatory: Transport restrictions in some countries due to dual-use explosive concerns.
Key Players
- CF Industries – major North American producer.
- Nutrien – integrated ammonia and downstream nitrogen fertiliser capacity.
- Yara International – global ammonia production and trade.
- OCI NV – major merchant ammonia supplier.
Outlook
Anhydrous ammonia will remain a cornerstone of nitrogen supply. Demand fluctuates with corn acreage and natural gas prices. The long-term shift toward green ammonia (produced with renewable hydrogen) may reshape its carbon footprint and trade flows.
