The injected air into the secondary reformer provides the nitrogen in Haber–Bosch reaction.Syngas is created when the combustion section’s exhaust stream passes through the catalytic component. The exit stream from the secondary reformer feeds to the shift reactors after cooling to an acceptable temperature in a waste heat boiler and condensing of steam in a separator. Carbon monoxide and steam react catalytically in the water–gas shift process, producing hydrogen and carbon dioxide. Presently, most ammonia plants use a combination of high and low-temperature shift reactors. The iron oxide and copper oxide–zinc oxide catalysts are used in high and low shift converters, respectively. Because CO and CO2 deactivate the iron catalyst in the ammonia converter, an absorber column and a methanator are used to lower CO and CO2 concentrations to a safe level. As a result, the low-temperature shift’s output product is cooled and fed into the absorption column [24]. The CO2 is absorbed by the commercial solvents in the absorber, and the outlet stream from the absorber is heated up and fed to the methanation reactor. In the methanator, the residual CO2 and CO are converted to methane through reverse reforming reactions at temperatures of 200–500°C. The catalytic hydrogenation of carbon dioxide and carbon monoxide to methane is thermodynamically favorable at low temperatures and high pressure. The methanator’s output stream is cooled, compressed, and dried before being sent to the ammonia converter. Attemperatures ranging from 450°C to 600°C and pressures up to 100bar, hydrogen and nitrogen react over a heterogeneous catalyst such as fused iron in the ammonia reactor, and ammonia is produced as follows