Experimental development of CO2, SO2 and NOx emission factors for mixed lignite and subbituminous coal-fired power plant

Standard emission factors for the emissions of CO2, SO2 and NOx from uncontrolled fossil-fuel power plants are widely available in the literature for different fuels and boilers. These factors are usually referred to pure fuels with steady mean compositions. However, environmental, economical and technological reasons can recommend the use of fuel mixtures, as one of the BATs (best available techniques) to be applied, in order to guarantee a longer life for the boilers. In this work, specific emissions factors for a large 1400 MW coal-fired power plant were obtained from continuous emissions monitoring data along 8 years, with different coals mixtures and combustion conditions. A methodology to estimate pollutants emissions from coal mixtures combustion using standard pure coal combustion emission factors was developed and tested. Differences in experimental emission factors (both specific and standard) allow to estimate the uncertainty of standard factors.