About Urea. Urea (a.k.a. Carbamide) is a nitrogenous organic compound composed of a carbonyl group attached to two amine groups, which plays an important role in many biological processes, being a product of the decomposition of proteins. Carbamide is found as a white and odorless solid, soluble in water, with very low toxicity. Urea has the highest nitrogen content among all solid nitrogen-based fertilizers, and for that, it is mostly used as a nitrogen-release fertilizer.

On an industrial scale, Urea is produced almost exclusively by the dehydration of ammonium carbamate, derived in turn from the reaction between ammonia and carbon dioxide. Usually, both reactions are carried out simultaneously, in a high-pressure reactor. It is worth noting that both ammonia and carbon dioxide reactants are supplied by ammonia-synthesis plants.

Commercial manufacturing processes generate aqueous solutions containing 70–87% urea, which may be directly used as fertilizer or, most commonly, further processed into granules, prills, flakes, etc. These urea solids can be coated in less-soluble chemicals such as sulfur and polymer, in order to mitigate negative aspects of urea fertilization. In fact, the majority of new commercial plants produce granules, in light of higher product quality when compared with prills.

Urea Handling. Urea should be stored in a designated area that maintains optimal conditions of coolness, dryness, and ventilation, ensuring protection against moisture and direct exposure to sunlight. When it comes to the transportation of Urea prills and granules in large quantities, various modes are employed, including trucks, ships, and rail cars. However, it is worth noting that prilled product is generally deemed less ideal for bulk transportation due to its relatively lower crushing strength, diminished shock resistance, and heightened tendency to cake compared to granules. Conversely, smaller quantities of the product can be conveniently conveyed using bags and drums.

Urea Production. Raw materials and the respective production processes employed in the manufacturing of Urea are listed below.

Urea Uses. The uses and applications of Urea may vary according to its specification. The main forms of Urea are coated grade (white prills or granules) and uncoated grade (white prills or granules).

Urea is also employed in the manufacture of urea-formaldehyde resins and urea-melamine-formaldehyde, used in a range of applications such as adhesives, laminates, molding compounds, coatings, and textile finishes.