NITROGEN FERTILISERS / UREA –EVAPORATOR

PROCESS INFORMATION
Urea is formed in the liquid phase following different reactions, in one of 3 types of process : Once Through ; Partial Recycle ; Total Recycle. Liquid NH3 is mixed with CO2 gas and any recycled Carbamate under high pressure (3200 psi ), with a conversion of say 60%. Urea solution is then fed through expansion valves and decomposers where unconverted Carbamate is driven off as NH3 and CO2 ( and recycled ). This produces 78% Urea solution which is concentrated to 99.7% purity in a steam Evaporator and the resultant concentrated solution goes to the Prilling Tower.Urea is entrained from the Evaporator by the exiting steam, which can contain up to 7,000mg/m3 with an average size of 3 microns.

PROBLEMS TO SOLVE
Air pollution.Intermediate solution, & thus final, product loss

DESIGN SOLUTION

• High Velocity ‘Becofil’ Candle Filters, standing type F, with Teflon Fibre elements and 304 Stainless Steel structure.
  
• High Velocity ‘Becofil’ Panel Filters, type HTP, with Teflon Fibre elements and 304 Stainless Steel structure.
  

IMAGES
	Urea Process Flow Sheet