PCDD/Fs removal efficiency by electrostatic precipitator and wetfine scrubber in an iron ore sintering plant.
This study investigates the removal efficiency of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) by the APCDs of an iron ore sintering plant, an electrostatic precipitator (ESP) and a wetfine scrubbing system (WS). The removal efficiencies of the ESP on the total PCDD/Fs concentration and the total PCDD/Fs I-TEQ concentration are 44.3% and 41.4%, respectively, while those of the WS are 66.7% and 68.4%, respectively, but the vapor/solid phase distribution changes after APCDs abatement. At ESP inlet, the PCDD/Fs account for 31.2% in vapor phase and for 68.8% in particulate phase while, at ESP outlet, the PCDD/Fs account for 63.3% in vapor phase and for 36.7% in solid phase. The ESP removes effectively solid-phase PCDD/Fs for its effectiveness to capture the particulate while it is ineffective in removing vapor-phase PCDD/Fs. It, on the contrary, increase for the vaporization within the ESP, especially for these congeners with a lower chlorination degree, and for the PCDD/Fs "stripping" from particulate to gas-phase during the sampling. At WS inlet, the PCDD/Fs account for 63.3% in vapor phase and for 36.7% in solid phase while, at WS outlet, the PCDD/Fs account for 21.4% in vapor phase and for 78.6% in solid phase. Considering that WS outlet temperature is about 40 degrees C, the PCDD/Fs vapor-phase condense to particles: therefore, even if the particulate is removed by WS, the final result is that PCDD/Fs percentage decreases in vapor-phase and increases in solid-phase.
Guerriero
Ettore
E
CNR - Istituto sull'Inquinamento Atmosferico, 00015 Monterotondo Scalo, Italy. guerriero@iia.cnr.it
Guarnieri
Alessandra
A
Mosca
Silvia
S
Rossetti
Gianluca
G
Rotatori
Mauro
M
D001572:Benzofurans / Q000302:isolation & purification*; D000072338:Dibenzofurans, Polychlorinated; D004787:Environmental Pollution / Q000517:prevention & control; D007220:Industrial Waste / Q000517:prevention & control*; D007501:Iron; D008669:Metallurgy; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000302:isolation & purification
D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D007220:Industrial Waste; D000072317:Polychlorinated Dibenzodioxins; D007501:Iron