مسعود مفرحی

In recent years, separation processes in chemical industries have grown significantly. Among these processes is the separation by adsorption process, spacially pressure swing adsorption. Many researches have done in this field, because of the efficiency and effectiveness of this process. Among the applications of this process is the air separation for oxygen and nitrogen production. Today, the cryogenic process is preferred to provide industrial gases for many applications.With regard to heat, cooling, process flows and losses, as well as industrial gas process and other units, we can improve efficiency and reduce costs. In this work, the nitrogen separation from the air is simulated by Aspen software (version 9). The pressure swing absorption part is simulated by the Aspen Adsorption module and the cryogenic distillation part is simulated by Aspen Plus module. The results are as follows: in the pressure swing absorption process, the purity of the product reaches 0.95 and in the cryogenic distillation process the purity reaches 0.99, which corresponds to the results of various references. Also, it can be concluded that the the cryogenic distillation process needs a lot of energy and it is very costly.