Simulation and Optimization of Air Separation Unit of Lorestan Petrochemicals Using Aspen Hysys Software

In this research, the simulation of air separation unit of lorestan petrochemicals was carried out using Aspen Hysys software and by selecting the Ping-Robinson thermodynamic model. In the following, comparing the simulation results of the unit with the actual data, a slight error of less than 0.7% in simulation was revealed. In addition, the energy optimization of the unit was accomplished by adding two process heat exchangers with a surface of 1.098 and 5.819 m2, respectively, instead of using the heat exchanger 901and before the entry of air into the Plant Air reservoir, which resulted in energy savings due to the elimination of the heat exchanger 901 in the new design. Moreover, in the new design , due to using the process converter, we were able to reduce the amount of water drained from the air into the Plant Air reservoir from 32.8 kg/hr to 38 kg/hr, both in terms of energy consumption and safety. The process is very important in cold weathers, especially in cold regions. In addition to the unit's optimization, the economic calculations waer carried out, in which the return on investment for the correction plan was estimated to be two months, which would result in a profit of $97975.12  per year.