【作者】 彭雯；

【导师】 严建华； 李晓东；

【作者基本信息】 浙江大学 ， 工程热物理， 2004， 硕士

【摘要】 焚烧法处理城市生活垃圾符合减量化、无害化、资源化的“三化”原则，在国外已得到广泛应用，目前在我国正逐渐得到推广。然而焚烧法产生的飞灰浓缩了重金属，如果处理不当会产生二次污染，因此飞灰被认为是危险废物，必须进行特殊处理。 本文对采用流化床焚烧炉混烧垃圾和煤后的布袋飞灰的浸出特性和沥青、添加剂S和NaOH固化焚烧飞灰展开了基础实验研究。 对飞灰进行了重金属的TCLP浸出特性实验，探讨了液固比、初始pH值及浸出时间对飞灰中重金属Pb、Cr、Cd、Ni、Cu、Zn的浸出影响。为飞灰的无害化处置提供科学依据。 对利用沥青固化城市生活垃圾焚烧飞灰的处理效果进行了实验研究。探讨了沥青与飞灰以不同比例混合对飞灰重金属Pb、Cr、Cd、Ni、Cu、Zn、Hg固化效果的影响。并对垃圾焚烧飞灰用作沥青混凝土的细骨料的可行性进行了简单探讨。 综合考虑重金属的固化效果、容积变化以及处理成本，对沥青与飞灰的质量比(m_AS╱m_FA，其中AS代表沥青，FA代表飞灰)为0.2时作了进一步的研究，在此基础上加入不同比例的添加剂S和NaOH，研究添加剂对飞灰重金属Pb、Cr、Cd、Ni、Cu、Zn、Hg的固化效果。选取了固化效果较好的飞灰混合物1(m_AS／m_FA=0.2，m_s／m_As+FA=0.067，m_NaoH／m_s=1.2)和飞灰混合物2(m_AS／m_FA=0.2，m_s／m_As+FA=0.1，m-（NaoH）／m_s=1.2)进行进一步的液固比和初始pH值浸出研究，以评价飞灰混合物中重金属Pb、Cr、Cd、Ni、Cu、Zn、Hg在不同环境下的固化效果，并将其与未经处理的飞灰、m_AS／m_FA=0.2的飞灰沥青混合物中重金属的浸出情况比较。更多还原

【Abstract】 Having the advantages of volume-reduction, weight-reduction and energy-recovery, incineration plays an important role in the disposal and utilization of municipal solid waste (MSW) and has been widely used abroad. Nowadays this technology is being popularized gradually in our country. However, the release of toxic substances such as heavy metals from MSWI fly ash will bring environmental problems. So MSWI fly ash should be treated before being landfilled.The emphasis of this study is on the fundamental experiment of the leaching behavior of heavy metals from fly ash which is from co-firing coal with MSW(municipal solid waste) in fluidized bed incinerator, and solidification in treating MSWI fly ash by mixing with asphalt and additives (S and NaOH).TCLP experiments have been performed to study the relationships between liquid-to-solid ratio (L/S), initial pH value, extraction time and leaching characteristics of heavy metals (Pb, Cr, Cd, Ni, Cu, Zn) in fly ash.The influence of mAs/mpA on the immobilization of heavy metals (Pb, Cr, Cd, Ni, Cu, Zn, Hg) was investigated. In addition, potential application of MSWI fly ash in asphalt concrete was studied simply.Considering the effect of solidification, the volume-change and the cost of disposal, the mixture (mAs/mFA =0.2) was further studied. For studying the effect of additives on immobilization, different mass of additives (sulfur and sodium hydroxide) were mixed with mixture of fly ash and asphalt based on the typical proportion. In order to evaluate the effect of solidification to fly ash in different leaching condition, the further leaching experiments about the fly ash mixture #l(mAs/mFA-0.2 , ms/mAS+FA=0.067 , mNaOH/ms=1.2) and the fly ash mixture #2 (mAs/mFA=0..2 , ms/mAs+FA =0.1? niNaOH/ms =1.2) were performed. Moreover, the comparison between heavy metals leachability from fly ash, the mixture of fly ash and asphalt (mAs/rnFA=0.2) and the fly ash mixture #1 and #2 was made.更多还原