垃圾焚烧飞灰中砷的赋存形态研究

The Study of Arsenic Speciation in Municipal Solid Waste Incineration Fly Ash

为实现垃圾焚烧过程中砷的释放控制,本文采集了六个地区两种炉型垃圾焚烧电厂的飞灰,通过分析飞灰中砷的赋存形态,阐释了垃圾焚烧过程中砷的迁移转化机理。结果表明,飞灰中砷总量存在一定的地域性差异,且炉排炉飞灰中砷含量高于流化床飞灰。飞灰中的As（Ⅲ）极少（0.34%~9.56%）,大部分砷在高温焚烧过程中与Ca、Fe、Al等元素化合物发生交互反应以As（Ⅴ）存在于飞灰中,此外,少量砷被硅铝酸盐固化在飞灰基质中.

To control the release of arsenic from municipal solid waste incineration （MSWI）, the mechanism regarding the arsenic speciation transformation during MSWI was studied in the present work. Several fly ash samples were collected from two kinds of MSWI plants in six areas and the arsenic speciation in the ashes was determined. The results showed that the total contents of arsenic differed in the samples from various regions, which were higher in the fly ash from grate furnace than these from fluidized bed incinerator. Few arsenic was in the form of As（m） （0.34%-9.56%） in the samples while most of the arsenic was in the form of As（V） owing to the interactions between arsenic vapors and Ca/Fe/A1 compounds. Moreover, part of the arsenic was stabilized in the ash matrix by the formation of aluminosilicates.