METHOD AND PROCEDURE FOR PRODUCING MELAMINE BY HIGH-PRESSURE PROCESS

摘要

The invention relates to a method for the production of melamine from urea via high-pressure process, which accomplished at pressure of 6.0~20.0MPa, temperature of 28°C~480°C in one single body reactor setting multi-tower tray up and down, in the process, the react liquids are not backimixing, react concentration direct, as well as flow direct of liquid phase and gas phase counter-current flow. The tower tray reactor comprises three sector (1) washing zone, (2) react zone, (3) post reactor. The reaction mixture bubbling react in the outer heating reactor and inner tray, then bubbling react via high concentration of ammonia gas in post react zone to yield high purity melamine (e.g.99.8%). The tail gas washed at the above reacting pressure is transfer to urea synthesis. It is operated simply with lowered energy consumption, and high reliability.