Research and Development of a New Coal Based Combined Cycle Power Plant Concept

Abstract

We propose a new coal-fired combined cycle power generation system featuring dust removal of high-temperature gas and wet desulfurization at the gas turbine outlet with the aim of improving the efficiency of the conventional IGCC system and reducing its construction cost. To study its feasibility, we conducted a fundamental study on the effects of alkali metal vapors in coal-derived gas on gas turbine blades and also studied remedial technology. The results of hot corrosion tests suggest that if the alkali metal vapor concentration in combustion gas is approximately 1 ppm or less current anticorrosion coating technology provides sufficient protection in practical use. The results of alkali removal tests show that 70% or higher removal rate can be achieved, which was considered a requirement for implementing the proposed system.