172868_Fertilizer Industry Handbook_with notes

Reduced energy consumption in nitrogen manufacturingThe Haber-Bosch synthesis has not been challenged for almost 80 years, buttechnology development in the 20 th century has reduced energy consumptiondown towards the practical and theoretical minimum.The energy base has changed, and technological advances have improvedenergy efficiency significantly. The graph illustrates that the industry is now moresensitive to energy price than developments in technology.Most nitrogen fertilizer plants utilize natural gas. However, any type ofhydrocarbon or coal can be used. In China most plants use coal. Energyconsumption can vary significantly. For an efficient plant using natural gas ittakes approximately 33 MMBtu of natural gas to produce one ton of ammonia(35 GJ). This translates into 40 MMBtu per ton nitrogen (42 GJ/tN). Convertingammonia to urea requires another 3 to 4 MMBtu per ton urea. This translatesinto about 48 MMBtu per ton nitrogen (51 GJ/tN)). As a rule of thumb, ammoniaplants using coal require between 50 per cent and 100 per cent more energy perunit of nitrogen produced.West European ammonia producers are highly energy efficientAmmonia producers in Western Europe have invested heavily in energy-efficienttechnology due to the historically high cost of energy in the region. According toEFMA, several ammonia plants in West Europe run on the lowest feasibleenergy consumption levels and emit the lowest possible amount of CO 2 pertonne of ammonia produced.The Western European ammonia industry is on average more energy efficientthan ammonia producers in other parts of the world. This is also driven by EUenvironmental regulations for pollution control, which requires running plants athigher standards than elsewhere.6970