FIELD: equipment of synthesis stage of process for producing urea from ammonia and carbon dioxide.
SUBSTANCE: apparatus includes high-pressure section operating practically at the same pressure values of synthesis reactor and condenser arranged inside said reactor. Condenser includes large number of flat plate like practically rectangular heat exchangers whose long sides are parallel to reactor axis. Each heat exchanger is made of two placed one onto other metallic sheets mutually joined by welding along their perimeter and forming inside heat exchanger preset-width cavity between them. Sheets from which heat exchangers are made are mutually joined by spot welding and they define in cavity of heat exchangers wavy path for fluid flowing. Said path includes mutually connected portions communicated through branch pipes for inlet of flowing heat transfer agent to heat exchangers and outlet of said agent from it. Preferable ducts for distributing flowing heat transfer agent fed to heat exchanger and for collecting outlet heat transfer agent are formed by means of tubes arranged in inner cavity of heat exchanger and secured to its mutually opposite long sides. At least one heat exchanger has internal partition passing from its one side to other opposite side and spaced from said opposite side by some distance for forming in cavity of heat exchanger U-shaped path for flowing heat transfer agent. Said path has descending and raising portions communicated with respective branch pipes passing outside from heat exchanger. Portions of U-shaped path have smoothly increased cross section area.
EFFECT: simplified design of zone for synthesis and condensation of reaction mixture for producing urea at improved efficiency of the whole process.
15 cl, 7 dwg
