UAN
It’s possible to produce Urea Ammonium Nitrate (UAN) solutions with relative ease thanks to Stamicarbon’s partial-recycle CO2-stripping process.We create UAN by using the residual ammonia remaining in the stripped urea solution, together with the ammonia in the high-pressure urea synthesis's off-gases. This is converted into ammonium nitrate in a neutralization reactor using nitric acid.
In the high-pressure synthesis section, carbon dioxide and ammonia are converted into urea – which contains unconverted ammonia and carbon dioxide. Stripping with carbon dioxide causes the greater part of these components to evaporate from the solution. From here, evaporated ammonia and carbon dioxide, together with fresh ammonia and carbon dioxide, are condensed in the pool reactor, with the heat from this condensation being used to produce low-pressure steam.
The condensed ammonia and carbon dioxide are partly converted into urea and water. In the low-pressure dissociation section, the stripped urea solution is almost entirely freed from ammonia and carbon dioxide. Then the overhead vapors of the reactor, mixed with off-gases from the dissociation section and the ammonia present in the urea solution from the urea solution tank, are all sent to the neutralization section.
The flowcharts below will explain how our process works.
flowchart 1
flowchart 2
