Conventional systems for exhaust gas cleaning and carbon capture and sequestration

Abstract Exhaust gas cleaning is a key process needed for a wide range of industrial plants for reducing pollutant emissions. Different types of pollutants which cause to greenhouse effect are produced in combustion media such as fly ash, NOx, SOx, CO2, acid gas, and dioxins and furans (PCDD/F) requiring a variety processes for separation of these pollutants from exhaust gas. The exhaust gas cleaning process is a multistep system where the first step is usually fly ash separation. Common technologies used for dust separation from exhaust gas include cyclones, electrostatic precipitators, and filters. There are some other materials like acid gasses and Hg which are completely separate from exhaust gas. After this, adsorption processes or selective catalytic reduction processes can be used for PCDD/F elimination from flue gas. NOx, SOx, and CO2 are the pollutants separated at the end of the exhaust gas cleaning process line. Unlike NOx removal technologies, CO2 separation processes are not scaled up to industrial size but some carbon dioxide capture and storage processes for industrial plants have been reported. In this chapter, conventional processes for exhaust gas cleaning are discussed and some of the latest achievements are reported.