Optimisation of the nitric acid process depends on good process visualisation tailored to the specific process parameters of the plant, improvements in combustion efficiency, reduction of N2 O emissions and the optimal use of platinum group metals.
Rapidly escalating natural gas prices forced plant closures across Europe during September. Worst affected was the UK, where a fire at a cross-Channel electricity cable and low output from wind energy has, combined with low domestic storage capacity led to a surge in demand for gas for power stations and wholesale gas prices reached a record 350 pence per therm (equivalent to $46/ MMBtu) in October. On September 15th, CF Industries announced that it was halting operations at both its Billingham and Ince fertilizer plans due to high gas prices. Although ammonia prices have also risen, they have not kept pace with gas price rises, and there is a limit to what farmers could be expected to pay. CF CEO Anthony Will said: “$900 is the gas cost in a tonne of ammonia and the last trade in the ammonia market that was done was $700 a tonne”. As these plants supply most of the UK’s carbon dioxide for food and drink manufacture, the government said it would provide “limited financial support” to keep the Billingham plant operational, and that plant re-started on September 21st. Meanwhile, BASF closed its Antwerp and Ludwigshafen plants in Belgium and Germany due to what the company called “extremely challenging” economics. Fertiberia ceased production at its Palos de la Frontera site in Spain, and Puertellano remained down for scheduled maintenance. Yara shut 40% of its European ammonia production in September, and OCI partially closed its Geleen plant in the Netherlands. Achema in Lithuania decided against restarting its ammonia plant following maintenance in August, and OPZ in Ukraine shut one ammonia line at Odessa, with Ostchem and DniproAzot likely to follow. Borealis in Austria also reduced production.
Troubleshooting and root cause analysis help to identify and solve problems in the operation of nitric acid plants and to prevent future reoccurrences. Johnson Matthey, Casale and Sabin Metal Corporation discuss their approach to solving problems in nitric acid plants to improve plant reliability and efficiency and to avoid unplanned shutdowns, costly replacement of equipment and loss of production.