利用旋风炉玻璃化处理垃圾焚烧飞灰实验研究

Experimental study on vitrification treatment of fly ashes from municipal solid waste incinerator by swirling furnace

在自行设计的旋风炉实验台上对焚烧飞灰进行玻璃化熔融实验,系统研究了焚烧飞灰熔融前后微观形貌、灰渣中重金属特性和浸出特性。实验结果表明,焚烧飞灰旋风熔融后成黑色的脆硬玻璃态熔渣,表层呈浅黄色。在熔渣中N i、Cr的固溶率最高,均超过95%以上;低熔点重金属多数挥发至熔融烟气和熔融烟道飞灰颗粒中,Cd的固溶率仅有21%,Pb和Zn部分固溶于玻璃态熔渣中,两者固溶率可达42%以上。Cu和As的固溶率分别为37%和18%。熔融后的玻璃态熔渣重金属浸出率明显低于熔融前的焚烧飞灰,且均低于美国EPA的标准限值。

The melting experiment of fly ash was conducted in a self-designed swirling melting furnace.The melting characteristics of fly ash were systematically investigated in terms of morphology,properties of heavy metals and leaching behavior.The experimental results show that the slag is black,frail and rigid by swirling melting.The fixation rates of nickel and chromium achieve the maximal value above 95%.The low boiling point heavy metals are volatilized into flue gas or on the particles of melting fly ashes.The fixation rate of cadmium is only 21%,and the fixation rates of lead and zinc reach above 42% in the glassy slag.The fixation rates of copper and arsenic are 37% and 18%,respectively.The leaching rates of heavy metals in glassy slag are much lower than those of raw fly ash,which are below the（EPA） regulatory limit values.