Electrostatic Precipitator Upgrade Opportunities Through a Review of Best Performers in Coal-fired Power Plants

摘要

This paper discusses the results of stack emissions testing conducted by several coal-fired power plants during the last three years to determine if additional steps need to be taken for meeting the upcoming federal regulations for particulate matter (PM), the hazardous air pollutant (HAP) surrogate for metals. The population of these plants is quite diverse. The coals utilized include both Eastern bituminous (Eastern) high sulfur and Powder River Basin (PRB) low sulfur coals. One plant utilizes a blend of PRB and Eastern coals. Two plants utilized wet flue gas desulfurization (FGD) systems for sulfur dioxide (SO_2) control downstream of the dry electrostatic precipitators (ESP). The nitrogen oxides (NO_x) control strategies on these plants include overfire air (OFA), low NO_x burners (LNB), selective non-catalytic reduction (SNCR), and selective catalytic reduction (SCR) systems. Two factors stand out from these test results: 1) the continuing efforts of plant operators to maintain ESP performance, and 2) the co-benefits of wet FGDs in reducing stack filterable emissions. Test results are compared with published reports from past practice. It is hoped that this paper allows other plant operators with ESPs to consider similar strategies for filterable particulate emission control.