PROCESS FOR PREPARING CONCENTRATED UREA SOLUTION AND AN APPARATUS FOR CARRYING OUT THE PROCESS

摘要

Process for concentrating a urea solution passing as a film along the inside of the tubes (2) of a vertical tube bundle the heat required being substantially generated by condensation of a gas mixture in a area provided around the bundle of tubes, the gas mixture being supplied to the area near one end of the tube bundle (2) and the urea solution to the other end of the tube bundle (2), and being passed substantially upwards through the heating area and it is ensured that the gas mixtureor condensate cannot flow back. Installation for carrying out the process wherein the heating area is divided into compartment by means of horizontal baffles (3) allowing an upwardly directed flow of the gas mixture and the condensate.