Urea production with multiple evaporators
AssigneeStamicarbon B.V.
InventorsRahul PATIL, Petrus Anna Maria Robertus SIMONS, Branislav MANIC
Life of this patent
Estimating the term…
Abstract
The disclosure pertains to a urea production process using a first and a downstream second evaporator in an evaporation section, a finishing section and a scrubber for treating off-gas of the finishing section. Condensate from the condenser of the second evaporator is supplied to the scrubber.
Claims14
A urea production process comprising:
- a) concentrating urea solution in a first evaporator of an evaporation section, to give concentrated urea solution and a first vapor,
- b) further concentrating said concentrated urea solution from said first evaporator in a second evaporator of said evaporation section, to give a urea melt and second vapor,
- c) solidifying said urea melt in a finishing section giving solid urea product and off-gas,
- d) scrubbing said off-gas in a scrubber,
- e) condensing said first vapor in a first condenser to give a first condensate,
- f) condensing said second vapor in a second condenser to give a second condensate,
- g) supplying said first condensate to a wastewater treatment section, and
- h) separately supplying said second condensate to said scrubber, wherein said second condensate is used as scrub liquid in said scrubber, wherein said scrubber additionally uses an acid scrub liquid.
A urea production plant comprising an evaporation section, a finishing section, a wastewater treatment section, and a scrubber, wherein the evaporation section comprises a first evaporator and downstream thereof a second evaporator, and a first condenser and a second condenser, wherein
- a) said first evaporator comprises an inlet for urea solution, an outlet for concentrated urea solution and an outlet for a first vapor,
- b) said second evaporator comprises an inlet for said concentrated urea solution, an outlet for urea melt and an outlet for second vapor,
- c) said finishing section comprises an inlet for said urea melt, an outlet for solid urea product and an outlet for off-gas and is configured for solidifying said urea melt into said solid urea product,
- d) said scrubber comprises an inlet for said off-gas and is configured for scrubbing said off-gas using scrub liquid,
- e) said first condenser comprises an inlet for said first vapor and an outlet for a first condensate,
- f) said second condenser comprises an inlet for said second vapor and an outlet for a second condensate,
- g) said wastewater treatment section comprises an inlet for said first condensate, and
- h) the plant comprises a connection for said second condensate from said outlet of said second condenser directly to an inlet of said scrubber.
Dependencies are inferred from the claim text.