As promising power generation technology, the advantages of Integrated Gasification Combined Cycle (IGCC) system are confirmed. However, high electricity production cost is the bottleneck before fully commercialization. IGCC complicated process, including gasification, power and Air Separation Unit (ASU) island, provides opportunities to increase its efficiency through process optimization and integration. But there is a requirement of suitable models considering both prediction accuracy and flexibility to overcome existing barrier of large-scale optimization problem. In this thesis, the gap is fulfilled by proposing simplified models for three IGCC islands. Firstly, the novel simplified gasification island model is proposed based on reaction mechanism simplification using Water Gas Shi...[ Read more ]

As promising power generation technology, the advantages of Integrated Gasification Combined Cycle (IGCC) system are confirmed. However, high electricity production cost is the bottleneck before fully commercialization. IGCC complicated process, including gasification, power and Air Separation Unit (ASU) island, provides opportunities to increase its efficiency through process optimization and integration. But there is a requirement of suitable models considering both prediction accuracy and flexibility to overcome existing barrier of large-scale optimization problem. In this thesis, the gap is fulfilled by proposing simplified models for three IGCC islands. Firstly, the novel simplified gasification island model is proposed based on reaction mechanism simplification using Water Gas Shit Reaction. After validation by experiment data, Cold Gas Efficiency optimization of IGCC plant gasifier is achieved with 10 % improvement. Then simplified model of power island is proposed and compared with rigorous commercial simulator. It is the foundation of further Gas Turbine performance optimization and Steam Turbine (ST) simultaneous parameter optimization and heat integration considering boiler feed water preheating. As the extension of simplified ST model, a novel shortcut model is proposed to optimize the regenerative retrofit for steam Rankine cycle. The most profitable regenerative scheme could generate from single to multiple extractions situations. After the validations with non-linear solver, the advantages of simple optimization procedures without building simulation and applying optimization algorithm are demonstrated in industrial case. Besides that, a simplified cryogenic ASU model is proposed and the non-standard operation conditions shows good performance for IGCC plant application. Finally, using all proposed models, the simultaneous parameter optimization and integration of IGCC system is completed in the aspect of economic and thermal performance. The simultaneous methodology is applied for gasification island firstly with 40 % profit and 4 % CGE improvements, and then for power and ASU island together with stepwise power output increment among cases.