Modeling of cryogenic air separation unit using an object-oriented approach and modelica-based mode.

Modelica-based modeling, which is a relatively new modeling approach, has attracted plentiful interests in recent years due to the flexibility and convenience. It has already been applied to many fields and achieved much progress. In the present paper, this approach is applied to the modeling of the cryogenic air separation unit (ASU), where a hierarchical and non-causal strategy is followed. The main objective of the present paper is to provide a potential object-oriented modeling method for the ASU, which may be able to reduce the modeling complexity and increase the flexibility. It differs from the conventional methods in terms of the framework, the basic model description, the ability of multi-domain unified modeling, etc. The modeling of some key subsystems of the cryogenic air separation unit is presented in detail as an example to illustrate the Modelica-based modeling, including the prepurification system, the heat exchange system and the distillation system.