高温除尘用微粉SiC多孔陶瓷的制备和性能研究

Preparation and Properties Study of SiC Porous Ceramic for Purifying High Temperature Dusty Gas

本文以平均粒径为2.4μm微粉SiC颗粒作为多孔陶瓷的主要原料,活性炭和石墨为造孔剂,再添加陶瓷粘结剂和羧甲基纤维素钠(CMC)溶液,采用逐层包覆工艺混料成型。将成型后的胚体在1300℃下烧结出不同陶瓷粘结剂含量(5～15wt%)(下同)以及不同成型压力(5～20 MPa)下的多孔陶瓷并研究了其气孔率、收缩率、过滤压降及抗压强度随陶瓷粘结剂含量以及不同成型压力下的变化。研究表明多孔陶瓷的气孔率随着成型压力由12.2MPa增加到48.8 MPa和粘结剂含量5%增加到15%气孔率逐渐降低,其抗压强度分别随着胚体成型压力的增大和粘结剂含量的增加而增加,烧结后胚体收缩率随粘结剂含量有先降低后增加的趋势。在粘结剂含量为10%时,成型压力19.52 MPa下多孔陶瓷的抗压强度和显气孔率都取得了较高的值,分别为31.75 MPa和29.87%,室温下空气流量为0.016 m3.h-1时,过滤压降为21.23 hPa。

The paper takes SiC particles whose mean grain size is 2.4 txm as the main raw materials, activated carbon and graphite as pore former, and adds ceramic binder and Sodium carboxymethyl cellulose （CMC） solution, mixed to shape with the coated process step by step. It sinters the embryo body after forming into porous ceramics which has different ceramic binder content （5-15wt%） an different forming pressure （5-20 MPa） in 1300 ℃, and discusses the changes of the porosity rate, shrinkage rate, filter pressure drop and compressive strength over the different ceramic binder content and different forming pressure. The research show that the porosity rate of porous ceramics reduced gradually while the forming pressure increases to 48.8 MPa from 12.2 MPa and binder content increases to 15% from 5%, and the compressive strength increases while the forming pressure of the embryo body and the binder content increases. The embryos body shrinkage rate after sintering has a tendency to increase aftera first decreases. When the binder content was 10% and the forming pressure is 19. 52 MPa, the compressive strength and show porosity of the porous ceramics are made of high value, 31.75 MPa and 29.87% respectively,when the air flow is O. 016 m3· h-lat room temperature, filter pressure drop is 21.23 hPa.