| Modeling, simulation and optimization are always the key problem of process systems engineering. In this thesis, large-scale cryogenic air separation system is studied. Modeling and parameters emendation for air separation system.The main contributions could be summarized as follows:1. Rigorous mathematical model is established for large-scale cryogenic air separation system. The SM and EO strategies are presented in steady simulation. Comparisons between calculated result and designed data show wider margin of variation. The necessity of modeling emendation was proposed.2. Thermodynamic parameters and equipment parameters are determined on the basis of characteristics of air separation system model. In order to enhance parameters estimation feasibility, parameters global sensitivity analysis is adopted to identify the key parameters originally. The number of the parameters finally reduced from 10 to 2. Two key parameters are estimated by least square method based on processed data. Apply the optimized parameters to simulate calculation. Compare the calculate result with the 5 actual operating modes, it’s shown that the simulate results tally well to the measured data. Substitute the optimized calculation thermodynamic parameter into thermodynamic equation to calculate phase equilibrium. Compare the result with experimental vapor-liquid equilibrium data and adopt un-optimized parameter in thermodynamic equation calculate result, which shows the thermodynamic model using optimized parameter can meet the experimental vapor-liquid equilibrium data better.3. Dynamic simulation for air separation system based on accurate steady model and parameter. Model dynamic characteristic was studied with air feed flux, argon distillate flux and oxygen flux fluctuated. The result of dynamical simulation could describe the dynamical responses of variable working condition. Reliable dynamic model provided for equipment operating and advanced control in future. |
