The Haber-Bosch process is the most widely used method for large-scale ammonia production. Since the reaction does not proceed to completion in the ammonia synthesis reactor, some of the reactants remain unconverted alongside ammonia at the reactor outlet, which is separated in this process using a refrigeration cooling system. The feasibility of replacing the cooling system with a supersonic separator is studied in this work through simultaneous modeling and simulation of all sections of the supersonic separator. The resulting differential equations were solved using MATLAB-Simulink software. After validating the ammonia condensation model, the performance of the supersonic separator for ammonia separation was examined in a real case study of the Haber-Bosch process at Khorasan Petrochemical Plant, focusing on both the separator’s efficiency and the influence of the feed cooling rate. The results showed that ammonia condensation can be effectively achieved until the gas phase reaches the required concentration in the supersonic separator. In this process, ammonia droplets with a radius greater than 4 μm are formed. By inducing a swirling flow in the gas, these large droplets easily migrate to the walls of the straight tube. The pressure recovery in the supersonic separator for the considered case study is approximately 14%, which closely aligns with the actual conditions of the refrigeration cooling system used in the Haber-Bosch process. Furthermore, the results indicate that the saturated temperature is the most optimal inlet temperature for ammonia separation, leading to maximum pressure recovery and minimizing the required nozzle length. A decrease of approximately 2 degrees in feed temperature from saturation reduces the pressure recovery to less than one-third, while an increase of the same amount reduces it to less than one-eighth. The results also indicated that the optimal inlet temperature remains essentially constant, even as the inlet ammonia concentration varies.

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