两种生活垃圾焚烧炉飞灰的理化特性分析

Study on Basic Physical and Chemical Characteristics of Fly Ashes from Two Municipal Solid Waste Incinerators

通过对2座正在运行的城市生活垃圾焚烧炉飞灰的物理、化学组成和热特性进行分析,结果表明:飞灰为粒径小于100μm的圆柱状、环状小颗粒,微观结构为不规则形,其主要化学成分为酸性氧化物、碱性氧化物、重金属及挥发性盐类等,其晶相组成主要为挥发性氯盐,如NaCl,KCl和CaCl_(2)等;二噁英、重金属及F,Cl,S元素在飞灰中含量较高,同时也存在含量差异较大现象。飞灰的熔融特征温度与其组成成分相关,在碱度系数为1时达到低值。飞灰的热灼减率受温度影响显著,其熔融过程主要经历干燥吸热、晶相变化吸热和熔融吸热3个阶段。

The physical characteristics,chemical composition and thermal characteristics of municipal solid waste incineration(MSWI)fly ash from two running incinerators were analyzed.The results showed that the fly ash was cylindrical and annular small particles with particle size less than 100μm,and the microstructure was irregular.The main chemical components of fly ash were acid oxides,alkaline oxides,heavy metals and volatile salts.Its crystalline phase was mainly composed of volatile chlorine salts such as NaCl,KCl and CaCl_(2).Dioxins,heavy metals and F,Cl,S were high in fly ash,and there were also large differences in content.The melting characteristic temperature of fly ash was related to the composition of fly ash,and reaches a low value when the albasicity coefficient is 1;The loss ignition of fly ash was significantly affected by temperature,and its melting mainly includes three stages:drying endothermic,crystal phase change endothermic and melting endothermic.