超高温烟尘过滤陶瓷滤料的制备

Preparation of ceramic filter for gas filtration at ultra-high temperatures

以硅酸铝纤维和莫来石纤维为主体材料,纳米二氧化硅作为高温陶瓷黏结剂,制备出一种适用于800℃下直接过滤的除尘滤料。研究了纳米二氧化硅添加量和烧成温度对多孔陶瓷过滤材料性能的影响,通过TG-DSC确定纳米二氧化硅的熔融温度,利用SEM表征材料的纤维粘结情况和孔隙结构。结果表明,纳米二氧化硅添加量为3%,烧成温度为1 300℃时,制备出的材料性能较佳,抗折强度为4.96 MPa,过滤阻力为139 Pa(过滤风速为1 m/min),气孔率为80%。

A hot gas filter used at 800 ℃ was prepared from aluminum silicate fibers,mullite fibers,and nano-silica powder as a high temperature ceramic adhesive. The influences of nano-silica content and the sintering temperature on the flexural strength of the ceramic filter and filtration resistance were studied. The melting temperature of nano-silica was measured by thermogravimetry（ TG）-differential scanning calorimetry（ DSC） analysis. The pore structure and morphology of the fiber binding was examined using scanning electron microscopy（ SEM）. The optimum preparing parameters were as follows： 3% nano-silica and sintering temperature of 1 300℃. The ceramic filter prepared using the optimum parameters showed better performance with a filtration resistance of 139 Pa,flexural strength of 4. 96 MPa,and 80% porosity.