COMPUTER SIMULATION OF AMMONIA SYNTHESIS REACTOR WITH THREE ADIABATIC BEDS

A mathematical model has been developed and tested with plant data for the ammonia converter with three adiabatic beds. The model is based on a material and energy balance in a differential element of beds and is subjected to the assumptions of uniform distribution of temperature and composition through a general cross-section and negligible mass and heat transfer in axial direction. The governing differential equations have been solved by Runge-Kutta of fourth order to obtain temperature and concentration profiles through the reactor. The agreement between calculated temperature and composition with plant data confirms the validity of the developed model. Once the validity of the model is checked, the effects upon the performance of the reactor of variables such as the inert concentration in the feed, pressure, inlet temperature, catalyst activity, space velocity and feed composition are surveyed