1359715 Urea production SNAM PROGETTI SpA 22 July 1971 [3 Sept 1970] 34539/71 Heading C2C A process for the production of urea comprises the steps of reacting CO 2 in a first or carbamate reactor with concentrated aqueous ammonia to form an aqueous solution of ammonium carbamate which is fed to a second or urea reactor wherein the ammonium carbamate so formed is dehydrated to form urea and from which there is obtained an aqueous solution containing urea and unreacted carbamate, and gas consisting of inert gases which are not reactants in the process, and in which process unreacted carbamate present in the urea-containing solution from the second reactor is decomposed and at least part of the decomposition products so formed are recycled in the gaseous phase to said second reactor to condense therein so that the thermal balance of the heat of formation of the carbamate which is decomposed and the latent heats of condensation and dissolution of the carbamate decomposition products is sufficient to supply the heat needed to maintain the contents of the second reactor at the dehydration temperature of the carbamate, and recovering urea from said solution.
