TABLE OF CONTENTS David Nordstrand
Subject Matter Expert Emissions Control
DTE EnergyDao N.B. Duong
Performance Engineer
Foster Wheeler, NABruce G. Miller
Associate Director, Energy Institute
The Pennsylvania State University
This chapter presents post-combustion emissions control strategies. This includes technologies for controlling particulate matter and acid gas control with an emphasis on sulfur dioxide and nitrogen oxides. Options for controlling mercury, the newest pollutant to be regulated, are also presented. The chapter concludes with a general discussion of carbon dioxide capture from flue gas streams, which is anticipated to be regulated in the future.
Particulate matter emissions from coal-fired electric utility boilers in the United States have decreased significantly since implementation of the1970 Clean Air Act Amendments. Several particulate control technologies are available for coal-fired power plants, including electrostatic precipitators (ESPs), fabric filters (baghouses), wet particulate scrubbers, mechanical collectors (cyclones), and hot-gas particulate filters. Of these, ESPs and fabric filters are currently the technologies of choice because they can meet current and pending legislation for particulate matter levels. While cleaning large volumes of flue gas, they achieve very high collection efficiencies and can remove fine particles. When operating properly, ESPs and baghouses can achieve overall collection efficiencies of 99.9% of primary particulates (over 99% control of PM 10, i.e., particulate matter with an aerodynamic diameter less than 10 ?m, and 95% control of PM
