【摘要】 以天津某生活垃圾焚烧厂飞灰为研究对象,通过额外添加典型组分的方法,研究了飞灰熔融特性的变化规律,并给出了碱度与最低流动温度的优选区间和玻璃化产品的质量验证。结果表明:SiO₂和Al₂O₃都能有效降低飞灰的熔融特征温度,SiO₂强于Al₂O₃;CaO和MgO能提升飞灰的熔融特征温度,CaO提升的较大;Fe₂O₃、Na₂O和K₂O能显著降低飞灰的变形温度,降低幅度达到了100℃左右,但对其他特征温度的影响不大。为了降低飞灰熔融的能耗,添加SiO₂调节飞灰碱度能最有效地降低流动温度。碱度区间在0.64～1.45时,飞灰的流动温度降低了140℃以上,分布在1 250～1 300℃。优选碱度为1.45时,玻璃化产品中玻璃体的含量接近100%,毒性鉴别结果远低于GB5085.3—2007设定的限值。更多还原

【Abstract】 Taking the fly ash from a MSWI plant in Tianjin as the research object,the variation of fly ash melting characteristics was studied by adding additional typical components,and the optimum range of alkalinity and minimum flow temperature was given,as well as the quality verification of vitrified products. The results showed that both SiO₂ and Al₂O₃ could effectively reduce the melting characteristic temperature of fly ash,and SiO₂ was better than Al₂O₃. Ca O and Mg O could increase the melting characteristic temperature of fly ash,and Ca O could increase more. Fe₂O₃,Na₂O and K₂O could significantly reduce the softening temperature of fly ash,with the reduction of about 100 ℃,but have little effect on other characteristic temperatures.In order to reduce the energy consumption of fly ash melting,added SiO₂ to adjust fly ash alkalinity could most effectively reduce the flow temperature. When the alkalinity range was between 0.64 and 1.45,the flow temperature of fly ash decreased by more than 140 ℃,which distributed between 1 250 ℃ and 1 300 ℃. When the optimum alkalinity was 1.45,the content of vitreous in vitrified products was close to 100%,and the toxicity identification result was far lower than the limit value set in GB5085.3—2007.更多还原