Conference article

Ammonia is one of the inorganic chemicals with the highest production rate in the world. This is explained by a wide range use of ammonia. Around 80 % of the produced ammonia is used for fer-tilizing agricultural crops. Aqueous ammonia solution is used in pharmaceuticals. Also, ammonia is used as a refrigerant and for the production of explosives. Safety and optimization of the ammonia synthesis process is an important industrial question, which was studied before and different ap-proaches were used. Since most of the research on this topic is focused on a stability analysis of the process in the steady state, there was a need to develop a dynamic model. A simple dynamic model was developed by Morud and Skogestad and they showed the steady-state van Heerden analysis to be inadequate in their work [1]. In the work [2] the importance of the dynamic process simulation is shown on the example of the ammonia synthesis process. Going further in this topic, we develop the basis for a synthesis reactor monitoring tool that can be used to identify the "distance/margin to instability" with respect to current load, pressure and temperature. For this purpose, we develop a simple dynamic model of the synthesis process in the reactor using the equation of state for the ide-al gas. A dynamic model is a convenient way to examine and analyze the process without the need for the actual testing in a real plant. In this paper, we discuss the stability of the ammonia synthesis process based on developed dynamic model.

Ammonia; synthesis; reactor; stability