| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for synthesizing urea, with which heat recovery can effectively be carried out. SOLUTION: This method for synthesizing urea comprises subjecting a urea synthesis solution from a urea synthesis column to stripping with a raw material carbon dioxide under pressure approximately equal to the urea synthesis pressure to separate a major portion of unreacted ammonia and carbon dioxide as a mixed gas from the urea synthesis solution, condensing the mixed gas by indirect heat exchange with the urea synthesis solution from which the mixed gas is separated and that is preferably decompressed to a pressure lower than the urea synthesis pressure and heating the urea synthesis solution by heat of condensation generated at the time of the condensation of the mixed gas. |
