# Modeling and Simulation of IGCC Considering Pressure and Flow Distribution of Gasifier
## 1 Introduction  
Coal will continuously be a main energy source for worldwide power generation in the coming decades, especially in developing countries such as China and India [1; 2]. The gas turbine combined cycle (GTCC) is an advanced power generation system but it cannot accept coal as a fuel directly, until integrated gasification combined cycle (IGCC) technology was developed to combine the clean coal technology and combined cycle system together. The IGCC power plant, with high specific power, high efficiency and low emissions, is one of the best solutions for coal burning power generation.  
C gasification is the core technology of the IGCC system, and the coal gasifier is the key component for the IGCC power plant. The US Department of Energy recognizes accurate simulation as one of the most important steps towards greater commercialization of gasification [3]. Field tests of the gasifier and IGCC cost a great deal of resources and might be dangerous; thus, investigations of the simulation method are needed to provide preliminary references.  
There has been a great amount of research into the gasification process and IGCC system modeling. [PERSON] [4] utilized ASPEN Plus to simulate the gasification and desulfurization process, and then analyzed the IGCC system performance. [PERSON] [5] discussed the simulation of entrained flow coal gasification of IGCC based on chemical reactions, and assumed that the pressure affecting the heterogeneous reactions was equal to the atmospheric value. [PERSON] [6] discussed the simulation and optimization of IGCC, focusing on the steam sub-system. [PERSON] [7] analyzed the difference between the IGCC plants with coal-slurry and dry coal gasifiers through system simulation, while [PERSON] [8] compared four IGCC power plants using Shell, Texaco, British Gas Lurgi (BGL) andKellogg-Rust-Westinghouse (KRW) gasifiers, respectively. [PERSON] [9] simulated an IGCC process integrated with a bitumen upgrading facility. However, the above studies are all focused on steady-state simulation, and are all based on the chemical reaction balance and thermodynamics analysis of IGCC plants. Then the later compartment dynamic models were developed to describe the internal gasification reaction and dynamic response in detail. [PERSON] [10] proposed a dynamic model of the gasifier using a shift equilibrium constant to describe the chemical reaction balance; however, the constant is only related to the temperature. [PERSON] [11] proposed another dynamic model for the gasifier of the IGCC power plant, using pressure-related coefficients to describe the heterogeneous reactions. [PERSON] [12] developed a more detailed dynamic model considering the gas-particle friction and the gas-wall friction. However, both of them set the pressure as constant. [PERSON] [13] discussed dynamic modeling and simulation of the IGCC process but the gasifier pressure was also given directly by the fixed designed parameter. [PERSON] [14] described the behavior of coal in an entrained-flow gasifier in detail, yet the pressure was also assumed to be constant. [PERSON] [15] utilized the volume-resistance characteristic method to describe the pressure and flow dynamic response of the gasifier but did not develop it into an IGCC system model. Therefore, it still lacks the consideration of pressure and the flow distribution of the gasifier, which reduces the accuracy of the IGCC system simulation.  
This paper will present an IGCC model containing an improved non-iterative gasifier model based on the volume-resistance method. The proposed model can calculate the distribution characteristics of the gasifier, especially the pressure and flow distribution, as well as its influence on the IGCC system performance. Since the volume inertias of the gasifier and other components have been considered in this model, the simulation can show a more convincing result for the system dynamic response of the IGCC power plant.