Product

High Quality Urea Granular Fertilizer

Urea is an organic compound that improves soil quality, provides nitrogen to plants, and increases crop yield. With 46 percent nitrogen content, granular urea has the highest nitrogen content of any solid nitrogen fertilizer and is by far the most significant source of nitrogen mainly due to its dominance in the Asian market. Urea is most commonly applied directly to the soil using conventional spreading equipment.

Urea Specifications

Uses of Urea

Brunei Fertilizer Industries (BFI) manufactures ammonia and then converts it into urea. Urea’s main demand is dominated by fertilizer applications, either as solid fertilizer or used in the production of urea ammonium nitrate (UAN). The remaining is used in a diverse range of industrial applications, the largest currently is for production of resins used in the wood products industry. Other industrial uses include production of melamine, NOx reduction and animal feed.

UREA PRODUCTION PROCESS DESCRIPTION

Ammonia is synthesised from hydrogen (derived from natural gas) and nitrogen (from the air). The impurities in the natural gas are removed in the hydro-desulphurisation (HDS) section at the start of the process. The methane from the natural gas mixed with steam is then converted into hydrogen and carbon oxides via the primary and secondary steam reformers in the reforming section. The air from the atmosphere is added to the secondary reformer to complete the reforming and required nitrogen is added to the process to manufacture ammonia in the ammonia synthesis section.

Apart from hydrogen, other products from the reforming section are carbon monoxide and carbon dioxide, all of which are poisons to the iron catalyst used in the downstream ammonia synthesis section and will need to be removed. The carbon monoxide is removed by first converting it to carbon dioxide and then the converted carbon dioxide is removed upstream of the ammonia synthesis section for use in urea production.

Essentially all the processes employed for ammonia synthesis is the Haber-Bosch process which involves the reaction of hydrogen and nitrogen under high temperatures and pressures over an iron-based catalyst to produce ammonia, which is then fully consumed in the production of urea.

Urea production is a two-step process where ammonia and carbon dioxide from the ammonia plant react to form ammonium carbamate which is then dehydrated to urea and water in the HP pool condenser and synthesis reactor. The reaction mixture containing ammonia, ammonium carbamate and urea is first stripped of the ammonia at HP stripper, and the resultant urea solution then passes through a number of decomposers operating at progressively reduced pressures. Unconverted carbamate is decomposed into ammonia and carbon dioxide and recycled back to the synthesis section.

The concentration of urea solution is then increased by evaporation and using the vacuum system to minimize biuret formation and crystallization. Once the concentration reaches the desired range, urea formaldehyde is added as an anticaking agent to reduce dust formation. The resulting urea melt is then fed into the granulation section to form urea granules as the final product. 

The urea production process is environmentally friendly and keeps the environmental emissions within the minimum levels and enables full recycle wastewater as make-up water.