PCDD/F Emissions from Hazardous Waste Incinerators in China

Abstract

In order to investigate the dioxin emission levels of hazardous waste incinerators (HWIs), and estimate their emission factors to the atmosphere, flue gas samples were collected from 12 HWIs in China, and analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Eleven HWIs are located in the south-eastern coastal areas of China, with rotary kilns being is the most widely used type of incinerator (more than 50% of the units), followed by pyrolysis kilns. Eleven incinerators had their emission levels below the current standards in China, while only four facilities exhibited emission levels below the European Union's limits. The highest concentration of PCDD/Fs, at nearly 1 ng TEQ/Nm 3 , was in the flue gas collected from an HWI with a waste burning capacity of 5 ton/d. This result was significantly higher than the values found for the other 11 incinerators, and thus was due to the poor performance of air pollution control devices and the influence of memory effects caused by PCDD/Fs emissions related to the start-up of the incinerator. In addition, the high dioxin emissions of this HWI were related to its feeding wastes, which mainly consisted of chemical industry waste residue with high a chlorine content. The emission factors of PCDD/Fs from the HWIs examined in this work were in the range of 0.27-18 µg TEQ/ton hazardous waste, with an average value of 3.74 µg TEQ/ton hazardous waste. It is estimated that 5.0 g TEQ of PCDD/Fs was released from HWIs to the atmosphere in China in 2010, which is less than that seen in 2004. The results of principal component analysis and hierarchical cluster analysis show all the investigated HWIs can be assigned to three groups, as verified by the results of nonparametric statistics. OCDD, 2,3,4,7, 1,2,3,4,7, are the main congeners in these three groups.

An Overview of PCDD/F Inventories and Emission Factors from Stationary and Mobile Sources: What We Know and What is Missing

“…The MSWIs without activated carbon injection exhibited higher PCDD/F emission factors (1.18 µg I-TEQ ton-waste -1 ) than those with activated carbon injection (0.711 µg I-TEQ ton-waste -1 ) in the study of Ni et al (2009). Wang et al (2014) also shows that without activated carbon the emission factors were nearly three times higher for HWIs. The combination of dry scrubber (DS), activated carbon injection (ACI) and fabric filter (FF), where the ACI adsorb the gas-phase PCDD/Fs and FF provided particle-phase PCDD/Fs removal, is treated as best available control technology for PCDD/Fs in flue gases, as reported in Lee et al (2003).…”

Evaluation of Thermal Treatments for Elutriated Mixed Incinerator Ashes. Part 1: Co-Incineration with Laboratory Waste

“…Therefore, the PCDD/F content in the ashes generated in an LW incinerator are five to ten times higher than those in municipal solid waste (MSW) incinerators (Wang et al, 2010;Liao et al, 2014). Similar levels have been found in hazardous waste incinerators due to the complicated composition of the input materials (Coutinho et al, 2006;Wang et al, 2014). High PCDD/F exposure is a health risk .…”

Atmospheric Deposition Modeling of Polychlorinated Dibenzo-p-dioxins, Dibenzofurans and Polychlorinated Biphenyls in the Ambient Air of Southern Taiwan. Part II. Wet Depositions and Total Deposition Fluxes

“…A recent surge of research on PCDD/Fs and PCBs has given us new information and challenges in Asia (Lin et al, 2014;Wang et al, 2014). This study (that is, the part II.)…”