Urea technology. A critical review

Urea production has presented some unique and difficult problems- reaction of ammonia and carbon dioxide must be carried out at high pressure and temperature, the reaction mixture is highly corrosive, the reaction cannot be completed in one pass, and the product decomposes at relatively low temperature. Significant progress in solving these problems has permitted construction of plants capable of producing 1500 t of urea per day. Resulting savings have made it possible to realize the major agricultural advantages of urea- high available nitrogen content, good plant response, and ease of application and storage.