The PFBC-CC Generation Power System Used Natural Gas Supplementary Combustion

Based on the first generation PFBC-CC, the natural gas was supplied as a fuel to increase gas turbine inlet temperature, so as to increase net efficiency of power generation. In this paper the analyses of technical, thermal and economic performance for system were carried out under different parameters, including reasonable dust remover inlet temperature, alkali metal concentration in gas before it entering gas turbine and cooling condition in gas turbine combustor. The thermal performance and power-production cost were also studied within the range of reasonable parameters. The results show that the flue gas temperature ≤ 973K at the inlet of hot filter can satisfy the conventional industry-use gas turbine requirement on the alkali metal content and dust content in flue gas. The net efficiency of this system can reach 43.3∼44.6% with sub-critical steam parameter condition and 45∼46.1% with supercritical steam parameter condition. With the increasing of steam parameters, the net efficiency of this system can be increased more. And the consumption of natural gas needs to be controlled in a reasonable level for obtaining the system preferable net efficiency and economics.