Effect of thermodynamic parameters on the capacity of an air separation unit in the Allam cycle

Abstract

The PURPOSE of the work is to establish the relationship between the thermodynamic parameters of the Allam cycle and the capacity of the air separation unit. The air separation plant is a consumer of electricity. To solve the problem, a calculation method is developed and functional dependencies are revealed.METHODS. A research methodology is presented that provides a connection between the thermodynamic parameters of the Allam cycle and its efficiency and fuel consumption, which, in turn, affect the capacity of an air separation plant designed to produce oxygen. The method assumes that the provision of oxygen combustion of methane occurs at their stoichiometric ratio. The method establishes a connection between the thermal efficiency of the cycle and the parameters of the working fluid. Formulas are presented for determining the consumption of standard fuel for the installation, the efficiency of electricity generation and the electric power of the oxygen preparation plant. When obtaining the final result, the factor of influence of the internal relative efficiency of the CO2 turbine is taken into account.RESULTS. The article shows that in the implementation of the Allam cycle based on carbon dioxide by burning methane in oxygen, an oxygen production unit plays a significant role. This is an energy-consuming equipment for own needs. Quantitative estimates have been made and it has been shown how the initial parameters of the thermodynamic cycle affect the capacity of the air separation unit, in which oxygen is produced. The article shows that its capacity can be provided at the level of 20% of the capacity of the power unit.