1. To achieve the most efficient production of good quality urea.
There is an optimum N/C ratio at which the urea concentration is maximum. Operating continuously at this optimum N/C ratio leads to the lowest energy consumption figures, the lowest ammonia emission figures and you will be able to increase the plant capacity by means of creep. You will obtain the most efficient urea production with the lowest urea cost price.

2. To avoid hazardous sampling procedures
Taking a sample from a system which operates at 140 bars or more, which contains a liquid with a temperature of 180 oC or more, which easily crystallizes and which contains hazardous ammonia is not a simple task. With a continuous N/C measurement instrument no hazardous high pressure samples need to be taken anymore at the outlet of the reactor.

3. To start up the plant more safe and quick
After a turnaround or shut down and certainly during the first start up, typically many instruments, like pressure and flow meters, are not reliable. A continuous N/C ratio measurement instrument has proven to be a valuable support for the operator to enable a smooth and quick start up of the plant, saving valuable time and significant costs.

2011_02_Huijben_SPIE_Why_every_Urea_Plant_needs_a_continuous_NC_meter.pdf