title: Dynamic Exergy Method for Evaluating the Control and Operation of Oxy-Combustion Boiler Island Systems.
abstract: Exergy-based methods are widely applied to assess the performance of energy conversion systems; however, these methods mainly focus on a certain steady-state and have limited applications for evaluating the control impacts on system operation. To dynamically obtain the thermodynamic behavior and reveal the influences of control structures, layers and loops, on system energy performance, a dynamic exergy method is developed, improved, and applied to a complex oxy-combustion boiler island system for the first time. The three most common operating scenarios are studied, and the results show that the flow rate change process leads to less energy consumption than oxygen purity and air in-leakage change processes. The variation of oxygen purity produces the largest impact on system operation, and the operating parameter sensitivity is not affected by the presence of process control. The control system saves energy during flow rate and oxygen purity change processes, while it consumes energy during the air in-leakage change process. More attention should be paid to the oxygen purity change because it requires the largest control cost. In the control system, the supervisory control layer requires the greatest energy consumption and the largest control cost to maintain operating targets, while the steam control loops cause the main energy consumption.
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Luoyu Road 1037, Wuhan, Hubei 430074, P. R. China.|Joint International Center for CO2 Capture and Storage (iCCS), Provincial Key Laboratory for Cost-Effective Utilization of Fossil Aimed at Reducing Carbon Dioxide Emissions, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Bo
authors.initials: B
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Luoyu Road 1037, Wuhan, Hubei 430074, P. R. China.
authors.forename: Haibo
authors.identifier: 0000-0003-4700-4933
authors.initials: H
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology , Luoyu Road 1037, Wuhan, Hubei 430074, P. R. China.
authors.forename: Chuguang
authors.initials: C
authors.lastname: Zheng
authors.affiliation: Joint International Center for CO2 Capture and Storage (iCCS), Provincial Key Laboratory for Cost-Effective Utilization of Fossil Aimed at Reducing Carbon Dioxide Emissions, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Zhiwu
authors.identifier: 0000-0003-1935-0759
authors.initials: Z
authors.lastname: Liang
mesh_terms: D062312:Islands; D010100:Oxygen; D013227:Steam; D013816:Thermodynamics
chemical_list: D013227:Steam; D010100:Oxygen