高铝粉煤灰多孔陶瓷膜管的制备及其性能研究

发布时间：2018-05-12 03:08

  本文选题：高铝粉煤灰 + 多孔陶瓷　； 参考：《合肥工业大学》2017年硕士论文

【摘要】：陶瓷膜管的结构包含支撑体,过渡层和过滤层三个部分。本文以固体废弃物高铝粉煤灰为原料,使用添加造孔剂的方法制备高铝粉煤灰陶瓷膜管支撑体,探究其中间过渡层陶瓷膜和过滤层陶瓷膜的涂覆和烧结工艺。使用一系列手段对高铝粉煤灰多孔陶瓷的物相组成、抗弯强度、孔隙率、孔径分布以及显微形貌等方面进行表征和测试,并使用Makipirtti-Meng经验速率方程分析高铝粉煤灰多孔陶瓷的烧结动力学。高铝粉煤灰多孔陶瓷膜管在过滤性能和机械强度方面与传统的氧化铝多孔陶瓷膜管相媲美,但是其制造成本大大降低,不仅可以解决令人头疼的固体废弃物环境污染问题,还可以“以废治废”,具有较高的社会意义以及一定的经济价值。本文以高铝粉煤灰为原料,淀粉和碱式碳酸镁作为造孔剂,添加高分子粘结剂,分别在1200-1500℃烧结温度下制备5组不同含量的多孔陶瓷样品,并测试其孔隙率、收缩率、气通量、水通量、抗折强度等性能。实验结果表明,烧结温度和造孔剂的种类和含量对多孔陶瓷的性能影响显著。碱式碳酸镁造孔作用明显优于淀粉,且随着造孔剂含量的增高,孔隙率,气通量,水通量逐渐升高,抗折强度略有降低。随着烧结温度的升高,气通量、水通量先增后减,在1350℃时达到最大值4854.24 m3m-2h-1bar-1、48.61 m3m-2h-1bar-1。综合考虑,添加质量分数为20%的碱式碳酸镁作为造孔剂,在1350℃温度下烧结2h,制备得到的高铝粉煤灰多孔陶瓷支撑体性能最佳。使用浸渍涂覆法在高铝粉煤灰支撑体上涂覆粒径为5μm的陶瓷粉体颗粒层,获得平均孔径为1.22μm的中间过渡层;涂覆粒径为500nm的陶瓷粉体颗粒层获得平均孔径为0.45μm的过滤层陶瓷膜。通过对其力学性能、过滤性能以及显微形貌的研究,探讨得出:中间过渡层陶瓷膜在1400℃温度时烧结2h,过滤层陶瓷膜在1000℃温度时烧结2h得到的氧化铝陶瓷膜具有较佳的机械性能,抗弯强度为8.31MPa,能够满足日常工作需求;同时它还具有良好的渗透性,其气通量为2222.2m3m-2h-1bar-1,孔径分布窄,过滤精度高。使用Makipirtti-Meng经验速率方程分析处理高铝粉煤灰多孔陶瓷样品的阶梯等温收缩(SID)数据,计算其烧结活化能。结果发现,高铝粉煤灰多孔陶瓷在烧结过程中只有一种烧结机制:1250-1400℃,其烧结活化能为679.28 kJ/mol。烧结机理可以理解为高铝粉煤灰中的Al2O3和SiO2随着温度的升高逐渐转变为莫来石(3 Al2O3·2SiO2)的烧结过程。此外,该计算结果进一步验证了陶瓷原料物相越复杂,杂质越多,烧结活化能越高的规律。
[Abstract]:The structure of ceramic membrane tube consists of three parts: support, transition layer and filter layer. In this paper, the ceramic membrane tube support of high aluminum fly ash was prepared by adding pore-making agent to solid waste high alumina fly ash as raw material, and the coating and sintering process of the intermediate layer ceramic membrane and filter layer ceramic membrane were investigated. The phase composition, bending strength, porosity, pore size distribution and micromorphology of porous ceramics with high aluminum fly ash were characterized and measured by a series of methods. The sintering kinetics of high alumina fly ash porous ceramics was analyzed by Makipirtti-Meng empirical rate equation. High alumina fly ash porous ceramic membrane tube is comparable to the traditional alumina porous ceramic membrane tube in filtration performance and mechanical strength, but its manufacturing cost is greatly reduced, which can not only solve the problem of environmental pollution caused by solid waste. It also has high social significance and certain economic value. In this paper, five groups of porous ceramic samples with different contents were sintered at 1200-1500 鈩，

本文编号：1876841