Computer Simulation And Energy Conservation Of The Cryogenic Air Separation Process For Nitrogen

Cryogenic Air Separation Process is widely used in industry for high purity nitrogen production.Existing research mainly focused on design method,but less on the analysis of existing device.In order to operate existing device energy efficiently more and find proper improvement solution,it is very important to make deep understanding with computer simulation technology.A 2000 m³/h N₂ production device was chosen as the base device.Aspen Plus was used to build a proper model and the model was verified by the process data.With this model,the operation parameters were analyzed in different working conditions.The bottleneck and operation limit were found and the simulation result were applied to train operators.In addition,the model was used to optimize the operation condition and flow sheet.Methods to increase the yield of N₂ and to quick deal with unqualified product were proposed.The structure of flow sheet was also optimized with this model.Two retrofit solutions were proposed.The first one is called“dry compressed air diversion”which can be easily implemented in existing device and would lead to considerable economic benefits.The second one is called“oxygen-enriched liquid air cooler”which is complex and with high extra investment.The second one fits for new device design.