Reticulated foams have a continuous skeleton network consisting of aluminosilicates and are used for capturing gaseous cesium released from spent nuclear fuel at high temperature. It has high stability to high temperature and good capturing performance. Homogeneous cell distribution and modified surface structures are indispensable conditions for stable operation and handling. In particular, triangularly shaped holes inside the struts were generated during the pyrolysis of polyurethane sponge as a sacricial template, which lead to limite the strength of the reticulated foam as well as cracks. However, several attempts have been focused on the increasing the strut thickness. Here, we have prepared ceramic foams by the polyurethane sponge replication method with roller squeezing. Ceramic slurry including additives was determined with consideration of its viscous behavior. After pre-sintering, infiltration under vacuum was conducted. Metakaolin slurry was filled partially into the triangular void. As a result, the compression strength was improved by structure modification without composition change.

세라믹 소재는 고분자 나노섬유 분리막과 비교하여 우수한 열안정성과 고투과 물성을 가짐으로써 지난 10여 년간 많은 주목을 이끌어왔다. 최근 들어 높은 다공도와 유량을 가지는 세라믹 섬유 분리막이 금속 산화물을 이용하여 주로 전기 방사법에 의해 제조되어 왔는데, 이러한 세라믹 분리막의 제조 단가를 감소하며 성능을 향상시키기 위해 나노섬유의 선택층 을 가지는 세라믹 분리막들이 전기방사 공정과 개질 과정을 통해 개발되었다. 본 리뷰에서는 최근 수년간 세라믹 섬유 분리 막의 개발을 위한 연구 동향에 대하여 정리하였다.

In this study, the porous ceramic filter was developed to be able to remove both dust and hazardous gas contained in fuel gas at high temperature. The porous ceramic filters were fabricated and used as a catalyst support. And the effects have been investigated such as the mean particle size, organic content and addition of foaming agent on the porosity, compressive strength and pressure drop of ceramic filters. With the increase of mean powder size and the organic content for the cordierite filter, the porosity was increased, but the compressive strength and pressure drop were decreased. From the results of the research, the optimum condition for the fabrication of ceramic filters could be acquired and they had the porosity of 58%, the compressive strength of 13.4 MPa and the pressure drop of 250 Pa. It was expected that this ceramic filter was able to be applied to the glass melting furnace, combustor, and dust/toxic gas removal filter.

본 연구는 알루미나 기반의 기능성 세라믹 필터의 물리적 특성(강도와 기공률)에 대하여 소결 온도와 영가철(ZVI) 함량의 영향을 파악하는 것이다. 기능성 세라믹 필터의 제조공정은 다양한 소결 온도(1150℃, 1250℃)와 ZVI 함량(10, 20, 30, 50%)조건에서 수행하였다. 소결온도와 ZVI 함량의 증 가됨에 따라 기능성 세라믹 필터의 강도는 증가하였지만 기공률은 감소하였다. 기능성 세라믹 필터의 강도와 기공률은 50%의 ZVI 함량과 1250℃의 조건에서 각각 99.01 MPa과 34.5%로 나타났다.

This work presents an experimental study of the influence of lifting velocity on cake formation during filtration. For design of hot gas cleanup system using ceramic filter reactor, the most important consideration is coating conditions of sorbent in filter surface (for example : lifting velocity, coating weight of sorbent, pulsing interval and removal effect for dechlorination and desulfurization). We studied the optimum operation condition as paticle size and lifting velocity using a ceramic filter reactor at 550oC. Based on the results obtained during cold and hot test, optimum lifting velocity in a ceramic filter reactor was selected 0.68 m/s. Also, the removal behaviour of the ceramic filter during filtration was studied using differential pressure. Optimum removal efficiency for dechlorination and desulfurization accomplished at differential pressure condition over 74 mmH2O.

The objective of this study was to evaluate bacteria removal ability of the metallic silver which was baked silver ion impregnated ceramic filter at heating condition. Silver leaking from baked ceramic filter was tested to sustain bacteria removal for a long time. Silver impregnated ceramic filter could remove E. coli completely at 1012 MPN/100ml to 1013 MPN/100ml of influent. However, ceramic filter without silver did not remove E. coli completely under the same condition. After baking, the silver impregnated ceramic filter almost didn’t leak out the silver ion from filter. Photo of TEM (Transmission Electron Microscopy) showed that absorbed silver ions remained in ceramic filter after baking process and most of silver were less than 10 nm. According to the increase in the amount of silver in the ceramic filter, removal efficiencies of E. coli were increased but turbidity removal was decreased. It can be accounted that increased removal efficiency of E. coli was from disinfection of silver that is in the ceramic filter. Simulated concentrations of bacteria agree well with the observed experimental effluent concentration data. Moreover, first-order decay coefficients increased to 0.0034/min after silver was added in the ceramic filter. Increase of first-order decay coefficient proves that silver-added ceramic filter can remove bacteria easily.