Emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurnas (PCDFs) in stack gas were analyzed from 21 municipal solid waste incinerators (MSWs) using high resolution gas chromatography equipment with a high resolution mass spectrometer (HRGC/HRMS) in 2015. The concentration of PCDDs/DFs was in the range 0.09 ~ 354.54 pg-TEQ/Sm3 based on the International Toxicity Equivalency Factor (I-TEF) and all MSWs complied with emission standards. The congener distribution of PCDDs/DFs was categorized into one group and two outliers via principal component analysis (PCA). Among the 17 PCDDs/DFs, 1,2,3,4,6,7,8-HpCDD showed the highest mass fraction (20.8%) and 2,3,4,7,8-PeCDF showed the largest TEQ contribution (42.9%).
Among the unintentional persistent organic pollutants (UPOPs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) were measured from a stack of 28 small-scale waste incinerators (SWIs) from 2013 to 2015. The emissions of PCDDs/PCDFs ranged from N.D. to 208.3 ng-TEQ/Sm3 with an average of 21.1 ng-TEQ/Sm3 based on the International Toxicity Equivalency Factor (I-TEF). The 28 stack gas samples were categorized into four types and evaluated by the score plot of principal component analysis (PCA). Furthermore, 17 PCDD/PCDF congeners were divided with the number of chlorine substitutions by a loading plot. The correlations between PCDDs and PCDFs were also estimated. The emissions of PCDDs/PCDFs from 19 SWIs were below the emission standards, while nine SWIs significantly exceeded them in this study.
Establishment of emission concentrations of PCDDs and PCDFs in emission gases from 85 domestic crematories were measured. The relationship between PCDDs/DFs and several factors such as structure, equipment and operational state of the crematory is discussed. Furthermore, emission of PCDDs/DFs from all crematories in korea is estimated. The following results are obtained: (1) total concentration (2,3,7,8- substituted isomers) of PCDDs/DFs was 0.113 ~ 14.34 ng/ Sm3, whose TEQ concentration was 1.815 ng-TEQ/Sm3; (2) total emission of PCDDs/DFs from crematories in korea was estimated to be 1.815 g-TEQ/yr.
In this study, PCDDs/DFs concentrations in flue gases from 58 crematories and in fly ashes and bottom ashes (mainly bone) from several crematories were measured to grasp the present state of PCDDs/DFs emissions from crematories. The effects of several factors were discussed to prevent PCDDs/DFs emissions from crematories. Total concentration of PCDDs/DFs was ranged from 0.113 to 87.461 ng/Sm3 and toxic equivalent concentration was ranged from 0.019 to 15.347 ng-TEQ/Sm3. As the results obtained in this research, the following measures to reduce PCDDs/DFs emission are recommended for existing crematories: (1) keeping the temperature at < 800oC or < 850oC in main/secondary chambers during a whole cremation, (2) lowering the temperature in the dust collector, (3) installing the high efficiency dust collector and reducing dust concentration to less than 0.02 g/Sm3, and (4) installing the sampling point for monitoring of PCDDs/DFs.
Establishment of emission standard of dioxins from crematories has been needed for their efficient management in korea. In this study, we investigate related regulation, guideline and management of crematory at home and abroad. Either dioxin legal basis or management of countries are compared and analyzed respectively. Crematories were distributed 51 place all over the country and total 265 crematories have been operated in 2000. Korea crematories have been operated 3 steps; incineration, cooling in furnace and collection of bone. This process is similar with Japanese process. But European process is different steps; incineration, keeping the temperature of furnace and collection of bone. In case of Korea, the resynthesis of dioxins in the cooling process due to the dioxin emissions higher than European process. This study has suggested three emission standards of dioxins from crematories based on survey of foreign standards and korean measurement data. The 1st suggested standard is 10 ng-TEQ/Sm3 in present facility, 5 ng-TEQ/Sm3 in new facility, the 2nd suggestion is 5 ng-TEQ/Sm3 in present facility, 1 ng-TEQ/Sm3 in new facility and the 3nd suggestion is 0.5 ng-TEQ/Sm3 in present facility, 0.1 ng-TEQ/Sm3 in new facility. When 2nd suggestion apply, at 2020 dioxin emissions(0.779 g-TEQ/yr) is expected to be approximately 71% reduction compared to 2010 year.