Mass Flow of Dioxins in a Landfill Site Disposed of Municipal Solid Waste Incinerator Ash
Yukio Noma*, Yasushi Matsufuji**, Mitsuyasu Takata*** and Keijiro Tomoda****Abstract
The mass flow of dioxins was investigated in a landfill site where municipal solid waste incinerator ashes have been mainly disposed. For this purpose we estimated the amount of dioxins received by the landfill site, discharged from the site, and retained in the site. Input dioxins were estimated from bottom ash, fly ash, cover soil, rain, and dust fall, output dioxins were estimated from the effluent and landfill gas, and retained dioxins were estimated from boring core samples.
The result showed almost all the input of dioxins originated from the fly ash, and almost all the output of dioxins originated from the effluent. The estimated amount of dioxins received into the site was 2,900g (45.9 g-TEQ) and those discharged from the site was 0.001g (0.000001 g-TEQ) . The dioxins output was only 0.00005% (0.000002% in TEQ) of the dioxins input. The results indicate that dioxins are not easily decomposed in landfill sites and water soluble dioxin discharge is very low. Therefore the input dioxins will be persistent for a long time.
Further studies are necessary in order to clarify the detailed mass balance of dioxins in landfill sites, because we reasoned from the limited date obtained in this study.
Key words: dioxins, waste landfill site, mass flow, fly ash, boring core