Application of quasi equilibrium theory in CH4+CO2 separation model based on hydrate formation

Key words:  hydrate  gas separation  quasi equilibrium process  phase equilibrium  model prediction

Abstract:

Based on the quasi equilibrium process theory, the hydrate formation process of binary gases was simulated. The equilibrium final state was compared with the predictive value of software CSMGem. The results show that new model can accurately predict the final equilibrium state. The relative error of the equilibrium pressure and the prediction from CSMGem is less than 3%. In addition, the new model can also reflect the change of relevant parameters in the process of hydrate formation through combining with the driving force factor of process. In the constant volume system, CH₄ will be concentrated in gas phase while CO₂ in hydrate phase through hydrate separation method. The reduced magnitude of system pressure decreased in the process of hydrate formation. High pressure and low temperature conditions play a positive role on the separation effect.