以油泥为主要原料的SiO2-Al2O3-CaO系陶瓷制备及机理

针对油泥含有机物并具有高硅、高铝组成的特点，提出以油泥为主要原料制备SiO2-Al2O3-CaO系陶瓷的方法，利用陶瓷高温烧结过程，将油泥中有机物分解以实现无害化，并将其中的SiO2和Al2O3等无机组分转化为陶瓷。制备了油泥、粉煤灰和大理石锯泥掺入量(质量分数)分别为50%、30%和20%的全固废陶瓷，分析了陶瓷在高温烧结过程的析晶和致密化规律。结果表明：所制备全固废陶瓷组分属于SiO2-Al2O3-CaO体系，其主晶相为钙长石和辉石；油泥中有机物的分解温度为300~730 ℃，有机物在陶瓷烧结过程中能够完全反应，该反应温度区间低于陶瓷最佳烧结温度1120~1160 ℃，对后续陶瓷高温致密化过程无显著影响；当烧结温度为1120 ℃时，油泥陶瓷力学性能较佳，其抗折强度为80.80 MPa，吸水率为0.21%，优于陶瓷砖国家标准的要求。

Preparation and Mechanism SiO2-Al2O3-CaO System Ceramics Using Oily Sludge as Main Raw Material

For containing organic components and high-silica/high-alumina composition, oily sludge as main raw material was prepared into SiO2-Al2O3-CaO system ceramics, with decomposition of its organic components for harmlessness, and conversion of its high-silica/high-alumina inorganic components into ceramics during its high temperature sintering process. Ceramics were prepared from solid wastes, including oily sludge, fly ash and marble saw mud with proportions (mass fraction) of 50%, 30% and 20%. Its crystallization and densification process during sintering process were further analyzed. The results show that main crystalline phases of the ceramics, which belong to the composition of SiO2-Al2O3-CaO system, are anorthite and pyroxene. The organic components decompose and volatilize in the range of 300-730 ℃, which is much lower than the sintering temperature from 1120 ℃ to 1160 ℃, and the volatilization process shows insignificant effects on the subsequent sintering and densification process. The ceramic sintered at 1120 ℃ has optimum physical properties with flexural strength of 80.80 MPa and water absorption of 0.21%, which are much better than the national standard.