Oxy-fuel Combustion and Clean Coal Technologies

Abstract

The competitiveness of coal relies on its wide availability and stability in supply and cost. Coal contributes to 39 % of worldwide electricity generation and plays an important role in global energy supply. For coal to serve as a source of the global energy supply, the greenhouse gases that are emitted from its utilization must be reduced. Oxy-fuel combustion technology is an emerging approach to capture post combustion CO₂. In this technique, coal is burned using a mixture of high-purity oxygen and recycled flue gas. Oxy-fuel combustion has some other advantages over conventional coal-air combustion, such as lower NOx and unburnt hydrocarbon emissions as well as easier CO₂ removal. Char gasification in mixtures of O₂ and CO₂ is also discussed in this paper. A sufficient active site, mainly consisting of catalyst in this study, was important not only to enhance char gasification reactions but also to prevent competitive reactions between char-O₂ and CO₂ gasification.