焚化爐灰渣電漿熔煉製成發泡陶瓷研究

Abstract

焚化爐，煉鋼廠等產生之大量灰渣，多為金屬氧化物如氧化鋁，二氧化矽，氧化鈣等; 如將其棄置，會造成環保的問題，如能回收利用，並創造出高的附加價值的產品，則為一舉兩得的解決辦法。 而灰渣原料之組成與常見的耐火材料相似，絕熱性好，不易與金屬產生高溫化學反應，為良好的抗高溫腐蝕的材料。 由建築材料方面看，此種原料較便宜，耐溫度高，如為泡沫或多孔質之爐渣其隔音效果更好且輕，如應用為室內裝潢用的材料，具有耐高溫，隔音，阻絕化學物質的功能。萬一火災發生時，可以拉長逃命的緊迫時間，且不易產生氯氣等毒性氣體，增加逃生的機會，為一有潛力發展的新建築用材料。 核能研究所於電漿熔融廢棄物處理時，意外發現部份泡沫狀的爐渣，因而基於上述的理由，期望對電漿熔煉發泡渣的行成，作進一步探討，在何種條件下，易行成泡沫狀的爐渣，以便將來利用電漿熔煉法製造泡沫狀爐渣。因此本研究擬由熱力學，動力學觀點對電漿熔煉發泡陶瓷的形成，在機制及實驗方面做一初步的探討。 本計劃，將利用實驗室內的小型電漿熔解設備，熔解不同成份的混合金屬氧化物，必要時添加一些助熔劑(fluxes)調整黏度，同時改變不同的氣體流量，以探討發泡陶瓷研製的可行性。

Great amounts of slags produced from incinerators or steel-makings contain Al2O3、SiO2 and CaO. If they were not disposed properly; the environment would be contaminated. However if they were recycled for the makings of valuable products, they would not be hazardous to the environment and would also be valuable. A slag’s composition has many similar properties as a refractory; such as good heat insulation、 less high temperature reaction with metals、and good high- temperature-corrosion resistance. The slags, especially foaming slags, would be potential materials for the inside-home-decorations due to their good insulation of heat and blocking of noise as well as chemical inert. The foaming slags would be beneficial in case of fire for they do not produce toxic gas easily and have good heat resistance. The time for escape would be increased. Therefore they have the potential of becoming new building materials. The nuclear research Institute has found that foaming slag would be formed during the plasma melting of waste. This brings up interest to know which conditions would be favorable to the production of foaming slag. Therefore this project is intended to study the mechanism of formation of foaming slag with plasma melting by thermodynamics and kinetics analysis. This study will investigate the formation of foaming slag with laboratory plasma melting facilities to melt different mixtures of metal oxides with necessary fluxes. The experiments will be carried out in plasma torch introduced with different gases and flow rates, and different graphite anode designs to examine the feasibility of slag- forming.