泥料含水量对粉煤灰陶瓷膜支撑体性能的影响

Effect of Ceramic Paste Water Content on Properties of Fly Ash Ceramic Membrane Support

泥料含水量是陶瓷生产中的重要参数,会影响陶瓷的收缩率、抗弯强度等性能。以电厂粉煤灰为主要原材料、糊精为造孔剂、羧甲基纤维素为黏结剂,采用挤出成型法制备了管状多孔陶瓷膜支撑体。通过控制陶瓷泥料用水量和烧结保温时间制备了不同支撑体,并对支撑体进行性能表征,考察了泥料含水量和烧结保温时间对支撑体微观结构、收缩率、孔隙率、孔径以及机械强度等性能的影响。结果表明:在水/固质量比质量为0.19时,1150℃保温烧结2 h获得孔隙率40.5%、抗弯强度23.6 MPa、平均孔径0.41μm的支撑体。制备的支撑体应用于脱硫废水微滤处理,固体悬浮物截留率99.98%。为制备低成本粉煤灰陶瓷膜支撑体提供研究基础,有利于膜法水处理的扩大化应用。

The water content of ceramic paste is an important parameter in ceramic production,which affects the shrinkage and flexural strength of ceramics.A tubular porous ceramic membrane support was prepared by an extrusion method with coal fly ash from power plant as a main raw material,dextrin as a pore forming agent and carboxymethyl cellulose as a binder.Different supports prepared at different water contents in ceramic paste and sintering holding time were characterized.Effects of water content in ceramic paste and sintering holding time on the microstructure,shrinkage,porosity,pore diameter and mechanical strength of the supports were investigated.The support with a paste water content of 0.19 prepared by sintering at 1150℃for 2 h shows an open porosity of 40.5%,a flexural strength of 23.6 MPa and an average pore diameter of 0.41μm.The support used in microfiltration of desulfurization wastewater can give a rejection rate of suspended solids of 99.98%.The results provide a research basis for the preparation of low-cost fly ash ceramic membrane support,which is beneficial to a promising application of membrane water treatment.