| 摘要: | 摘要 隨著垃圾灰渣的產量日趨增加，灰渣的妥善處理與處置將取代過去的垃圾掩埋，成為國內迫切的環保問題。本研究針對都會垃圾焚化廠產出的底灰與飛灰進行實驗式規模且自行研發的電漿熔融爐高溫處理灰渣，透過灰渣性質分析、灰渣調質、空冷，再結晶與磁選等程序，探討操作條件對於灰渣熔融後的垃圾熔渣性質影響，並經由相關文獻分析、實驗成果，以及統計方法進行綜合評析，探討灰渣熔融的前處理程序、再結晶操作條件與資源化策略。 研究結果顯示，焚化灰渣經熔融後，熔渣重金屬溶出率皆遠低於法規值，可進行再利用與資源化。熔渣經再結晶程序，所產生的主要晶相為鈣鋁黃長石(Gehlenite)與鈣鎂黃長石(Akermanite)，而晶相的產生使機械強度大幅提升。材料性質方面，空冷、再結晶與磁選熔渣吸水率皆低於1.0%，符合天然粒料的規範值。但因比重與硬度值規範不同，使各類熔渣的應用性有所差異。空冷熔渣適合做為細粒料或次級舖面材料；再結晶熔渣的性質介於天然粗粒料與再生粗粒料之間，應用價值明顯高於空冷熔渣；磁選熔渣經鹼矽骨材反應試驗後，磁選熔渣介於無害骨材與潛在有害區域之間，因此若磁選熔渣做為粒料方面應用可能較不適合，但因磁選熔渣屬玻璃質熔渣，且無結晶相的產生，因此可做為玻璃材料應用。 Abstract Along with the gradual increasing yield of the refuse residues, the appropriate management and treatment of the residues has become an urgent environmental protection problem in this country. The present study aims at the high temperature treatment of the bottom ash and fly ash, with a self-developed laboratory-scale plasma furnace, and then verifying the various influences on the properties of refuse slag through different procedures, such as the analysis of residues properties, residues composition adjusting, air-cooling and recrystalization and magnetic separation etc., and finally performing a comprehensive evaluation of such influences by the exploration of literatures as well as experimental results, so as to establish the pre-processing procedure for the refuse melt, the operational conditions of recrystalization and recovery strategy. In light of the study results, it is revealed that the dissolution ratio of heavy metals contained in the incinerator residues, after the implementation of the melting process, is much lower than the regulatory standard. The hardness of recrystalization slag is dramatically higher than that of magnetic separation slag and air cooling slag, therefore it is suitably used as pavements; and the magnetic separation slag belongs to the glassy slag, which is suitably used as the raw material of glass. Both the air cooling slag and magnetic separation slag don’t have a clear crystalline structure, whereat the recrystalization slag mainly consists of Gehlenite (Ca2Al2SiO7) and Akermanite (CaMg(SiO7), however, the strength of Wollastonite (CaSiO3) is dramatically much lower than others, in addition to its crystalline strength will be decreasing further along with the longer time of heat treatment. The optimum temperature maintaining time for the air cooling slag is one hour, and at this moment the crystalline structure of slag will have the maximum strength. While comparing the values, it is found that the value acquired from the alkali silica reaction of recrystalization slag, magnetic separation slag and air cooling slag is at least 1.0 larger than the Sc/Rc ratio of the slag, wherein the ratio of magnetic separation slag lays at the border between the non-hazardous area and potential hazardous area, however the values of both air cooling slag and recrystalization slag are then lay in the non-hazardous area. |
