Operation method of urea production plant including multiple systems

摘要

An operation method of a urea production plant including multiple systems that can prevent a considerable decrease in urea production even when an ammonia synthesis facility is shut down. At a time of producing urea from CO₂ and ammonia, in a case where urea production plants including at least two systems are arranged in parallel, when an ammonia production facility (10A) of one of the systems is shut down, liquefied ammonia stored in the shut down system is used, and a CO₂ recovery amount in a CO₂ recovery facility (23) in an ammonia synthesis facility (10B) of the other system is increased. Synthesis of urea can be then continued by a urea synthesis unit (30A₁) in the shut down system by using the increased recovered CO₂ and the liquefied ammonia.