Experimental study on Dispersion of incineration residue at MSW Landfill

在日本，二恶英一直是一个重大的环境问题。焚烧残渣含有二恶英，倾倒在垃圾填埋场会对环境造成风险。在本研究中，以水分含量为主要变量，利用实验室规模的风室研究了残留物分散的可能性。将几个生活垃圾焚烧炉的底灰注入风室，模拟垃圾填埋场的倾倒实践。本研究以水分含量为主要控制变量，测定了室内空气采样器采集的灰样和分散灰的颗粒大小，发现颗粒大小和水分含量是影响焚烧灰分散的关键因素。可以得出的结论是，在焚烧炉中对炉底灰润湿的常见做法是足够安全的，可以防止扩散。飞灰中二恶英的浓度远高于底灰，因此填埋前应进行固化处理。固化后的飞灰中只有很小一部分细小的颗粒会分散。

In Japan dioxin has been a big environmental concern. Incineration residue contains dioxin, and pose an environmental risk when dumped in a landfill. In this study, the possibility of dispersion of residues was studied by using lab-scale wind chamber, with moisture content as an main variable. Bottom ash from several MSW incinerators were injected in a wind chamber to simulate dumping practice in a landfill. Moisture content was main control variable in this study, and particle size of ash samples and dispersed ash captured by air samplers in the chamber were determined.Particle size and moisture content are found to be key factors for dispersion of incineration ash. It can be concluded that common practice of moistening of bottom ash in an incinerator is safe enough to prevent dispersion. Fly ash has much higher concentration of dioxin than bottom ash, so solidification treatment should be applied before landfilling. Solidified fly ash have only negligible fraction of fine particle to be feared for dispersion.