Influences of Non-SCR De-NOx Technologies on NOx and Dioxin Emissions in Full Scale Municipal Solid Waste (MSW) Incinerators

Abstract

Abstract To meet the increasingly stringent NOx emission regulations, multi non-selective catalytic reduction (non-SCR) denitrification (De-NOx) technologies are adopted in municipal solid wastes (MSW) incineration plants; but their individual or joint impacts on NOx and dioxin emissions are not systematically investigated. In this research the emissions of NOx and dioxins from three MSW incineration plants were investigated, so that the impact of different non-SCR De-NOx technologies including selective none-catalytic reduction (SNCR), De-NOx with organic amine-containing compounds as reductants (so-called PNCR), flue gas recirculation (FGR) and air staged combustion (ASC) on NOx and dioxin emissions can be evaluated. The emission results are compared and linear regression analysis showed that SNCR is most effective for inhibiting NOx and dioxin emissions, therefore SNCR should be primarily chosen. PNCR is an optional technology and its performance should be further improved in order to replace SNCR. FGR level has a strong influence on dioxin emissions, with a lower level being better; ASC level has none decisive effect either for De-NOx or for dioxin emission control, but its higher level seems better. The recommended non-SCR De-NOx technology combination mode is SNCR + PNCR + FGR25% + ASC80%. This study provides valuable suggestion for choosing suitable non-SCR De-NOx technologies for cost-effectively controlling NOx and dioxin emissions.

Keywords

• MSW incinerator
• De-NOx
• Dioxin
• SNCR
• PNCR
• FGR