Abstract
Coal is the main fossil fuel of thermal power plants in China. CO_2 emission reduction is a key factor in supporting the continued use of fossil fuels, particularly coal consumption. Characteristics of coal-fired flue gas were presented, and four main technologies, solvent absorption, membranes, adsorption, and cryogenic were reviewed. With regard to the characteristics of each technology and coal combustion flue gas described in the above, chemical absorption process was regarded as the most promising to be put into large scale use. An aqueous ammonia based multi-pollutant control process for scrubbing SO_2, NOx, mercury, and CO_2 from flue gas was developed on the basis of relative literatures. The following advantages of the aqueous ammonia process over conventional amines were examined: lower heat requirement, more CO_2 absorption, lower chemical cost, and multi-pollutant control with by-products.
