High emissivity coating of the refractory surfaces in the radiant section of the primary reformer reduces the radiant heat reabsorbed by the combustion flame and flue gases. This increases the radiant section efficiency and reduces the reformer bridge wall temperature. Less fuel is thus required to achieve a given reformer process temperature. Expected useful life of the coating is about 4 years (FAI, 2013).
Two Indian ammonia plants have implemented this measure during 2008-09. (FAI, 2013)