Urea process Split Flow Loop™ (U6000)

Suitable for production up to 6000 t/d.

Key features

• Proven design
• Optimized plant cost
• Low energy consumption

Advantages stemming from economies of scale are driving the quest for even larger plants, which in turn is shaping the future of fertilizer production. This requires plant design to be reviewed and new technical solutions devised while improving, or at least not penalising, safety and reliability aspects.

In conventional CO2 stripping urea plants current limits in the design and construction of the stripper limit production to a maximum of 4000 MTD on a single line. To overcome such limitations Casale has devised the U6000 process where the advantages of its Split Flow and Full Condenser™ technology are combined with those of a Medium Pressure decomposing section.

The stream leaving the urea reactor is split into two parts: one goes to a conventional stripper while the balance is sent to a parallel decomposing (MP section) section operated at pressure of 18 bar. The key items of this section are the Decomposer and the Condenser. In the former the unreacted carbamate is partially decomposed. The resulting vapours are then processed in the Condenser with the aid of a carbonate solution coming from the downstream Low-Pressure section and then recycled to the HP scrubber as carbamate solution.

The urea solutions from the Decomposer and the Stripper are mixed and sent to the downstream LP decomposer.

MP Split and Split Flow Loop™ technology nowadays are consolidated process schemes for CO2 stripping urea plants and are steadily in operation in several plants. The U6000 Technology makes it possible to produce 6000 MTPD and more in a single train plant.