【作者】 王宇峰；

【导师】 李晓东； 严建华；

【作者基本信息】 浙江大学 ， 能源环境工程， 2011， 硕士

【摘要】 在我国,医疗废物的处理方法应用最普遍的是焚烧法。焚烧法是一种可同时实现废物无害化、减量化、资源化的处理技术,但也带来了一些亟待解决的环境问题。焚烧过程产生的飞灰含有强烈的致癌、致畸、致突变的二恶英和重金属等,如果排放前没有得到妥善的处理,它们将从排放源通过大气传输到各处而污染水源,进入食物链,给人和环境带来危害。因此,飞灰在排放前必须经过处理以降低其毒性。本文从医疗废物的定义出发,对医疗废物的处置、焚烧飞灰的处置,飞灰重金属的危害、焚烧过程飞灰重金属的迁移特性以及浸出特性等进行了详细的介绍和分析,同时还利用水热法对医疗废物焚烧飞灰中重金属的稳定和二恶英的降解进行了详细的实验研究。1)在管式炉试验台上结合电镜、能谱、X射线衍射、原子吸收光谱等分析手段研究了模拟医疗废物热解及焚烧后飞灰的颗粒形态、化学组成以及重金属含量等。也分析了实际医疗废物焚烧飞灰的重金属蒸发特性。2)研究了医疗废物焚烧飞灰重金属的浸出特性。重金属的浸出能力受到浸取剂pH值、浸取剂种类、液固比、浸取时间等四种控制因素不同程度的影响。3)研究了在水热条件下医疗废物焚烧飞灰中重金属的稳定化和二恶英的降解。反应后飞灰中的重金属由于形成了稳定的硅铝酸盐而使浸出毒性降低,同时二恶英的降解效果显著。更多还原

【Abstract】 Incineration, as the most popular medical waste disposal in China, is a technique which can make wastes harmlessness, reduction and resource, while causing some urgent environmental problems. Fly ash produced by incineration process contains dioxins and heavy metals which may cause carcinogenesis, teratogenesis and mutagenesis. They will pollute water, enter the food chain and harm to humans and environment as they are transmitted from the original emission source to everywhere by air if they are not been proper treated before emission, So fly ash need to be well treated to make it less poisonous before emission.In this article, we begin with the definition of medical waste and then introduce and analysis in detail on the treatment of medical wastes, the treatment of incineration fly ash, the harmfulness of fly ash and heavy metals, the vaporization and leaching property of the fly ash and heavy metals in incineration procedure. At the same time, the stability of heavy metals and the degradation of dioxins in fly ash in medical wastes incinerators is studied in detail using hydrothermal method.1) With various analysis methods such as electron microscopy, energy spectrum, X-ray diffraction spectra and atomic absorption spectrometry, we studied on the particle shape, chemical characteristics and heavy metals content of incineration fly ash and pyrolysis of simulated medical wastes using tube-type furnace test bench. The volatilization property of heavy metals in actual medical waste incineration fly ash is also been studied.2) Heavy metals leaching characteristics in fly ash from medical wastes incinerators is been studied. The leaching ability of heavy metal is impacted by the ph-value of extractants, the type of extractants, liquid to solid ratio and immersion time.3) The stability of heavy metal and the degradation of dioxins in fly air from medical wastes incinerators is studied under the hydrothermal process. After the experiment, the poisonous of the leaching heavy metals in the fly ash is decresed due to the formation of stable aluminosilicate and the effect of the degradation of dioxins is obvious.更多还原