• Nuclear Engineering and Technology
• /
• 제48권5호
• /
• pp.1230-1236
• /
• 2016

This study aims to determine the effect of fly ash with a high replacing ratio of clay on the radiation shielding properties of bricks. Some interaction parameters (mass attenuation coefficients, half value layer, effective atomic number, effective electron density, and absorption efficiency) of clay fly ash bricks were measured with a NaI(Tl) detector at 661.6 keV, 1,173.2 keV, and 1,332.5 keV. For the investigation of their shielding behavior, fly ash bricks were molded using an admixture to clay. A narrow beam transmission geometry condition was used for the measurements. The measured values of these parameters were found in good agreement with the theoretical calculations. The elemental compositions of the clay fly ash bricks were analyzed by using an energy dispersive X-ray fluorescence spectrometer. At selected energies the values of the effective atomic numbers and effective electron densities showed a very modest variation with the composition of the fly ash. This seems to be due to the similarity of their elemental compositions. The obtained results were also compared with concrete, in order to study the effect of fly ash content on the radiation shielding properties of clay fly ash bricks. The clay fly ash bricks showed good shielding properties for moderate energy gamma rays. Therefore, these bricks are feasible and eco-friendly compared with traditional clay bricks used for construction.

• 한국세라믹학회지
• /
• 제33권7호
• /
• pp.771-778
• /
• 1996

Utilization of fly ash by-produced from coal fired power plants and classified as general waste became very important problem to solve in the environmental protection and recycling of waste materials. The possibility of large scale substitution of fly ash as a raw material for bricks and wet tiles was highly expected because the chemical compositions of fly ash were mostly Al2O3 and SiO2 and the properties of it were very similar with clay. Accordingly in order to investigate the substitutional limit these specimens were substituted from 0 to 100 wt% fly ash by 20wt% increment for clay. Fly ash-clay bodies were fired at 1200, 1250 and 130$0^{\circ}C$ and then their properties were measured, It was found that these specimens sintered at 125$0^{\circ}C$ had a good bending strength. Especially when these sintered bodies were added to 20, 40 and 60 wt% fly ash the bending strength of those were 201 , 205 and 191kg.cm2 respectively with the water absorption below 1%, This showed that fly ash could be substituted ab 60 wt% in this experiment.

• 한국세라믹학회지
• /
• 제33권2호
• /
• pp.135-142
• /
• 1996

Fly Ashes which are produced from coal-fired powder plants and classified as general waste can be used as raw materials for bricks and tiles because of their compositional similarity with clays. There was a limit of substituting fly ash for clay because plasticity decreased with increasing fly ash additions. Accordingly this study tried to suggest a feastibility of enhancing the substitution ratio by controlling the interfacial properties of fly ash. The slip with 1:1 volume ratio showed that best dispersive characteristics under the condition of pH 2 Filter pressed cakes made of pH 2 slips also showed better plastickity than those of untreated ones. of pH 2 Filter pressed cakes made of pH 2 also shwoed better plasticity than those of untreated ones.

• 자원리싸이클링
• /
• 제19권2호
• /
• pp.10-18
• /
• 2010

본 연구는 소성공정으로 MSWI fly ash를 혼합한 일차점토와 적황토 공시체의 특성을 알아보기 위하여 진행되었다. 최대 20 wt% MSWI fly ash를 혼합한 공시체는 SEM, UTM, ICP 등의 방법으로 분석되었으며, 그 결과 $P_{10}$공시체는 휨강도가 증가하였고, $R_5$공시체는 압축강도와 휨강도가 증가하였다. 또한 중금속 용출량도 기준치를 만족하였다. 이것은 MSWI fly ash가 소성공정에 의한 벽돌제조에서 기존 재료의 부분대체에 적합하다는 것을 나타내는 것이다.

• 대한환경공학회지
• /
• 제31권2호
• /
• pp.114-118
• /
• 2009

본 연구에서는 소각재와 하수슬러지, 용융슬래그 등을 이용하여 기존의 벽돌을 대신 할 수 있는 건축외장재를 제조하고,사용 재료의 혼합비와 소성온도 등 적정 제작 조건을 도출하고자 한다. 외장재 제조는 재료를 각 비율별로 성형하여 상온과 $160^{\circ}C$에서 각각 24시간 동안 건조 후 1,080~$1,130^{\circ}C$에서 2시간 동안 소성하였다. 소성한 다음 제조한 외장재 시편의 압축강도를 측정해 본 결과 소성온도가 증가할수록 압축강도는 증가하였으며, 소각재의 함유량이 적을수록, 용융슬래그의 함량이 증가할수록 압축강도가 증가하였다. 본 연구에서 도출된 외장재 제조 적정조건은 소각재 : 용융슬래그 : 하수슬러지 : 점토의 비율이 10 : 20 : 5 : 65로 제조된 시편을 $1,115^{\circ}C$에서 소성한 시편의 압축강도가 41 MPa 이상으로 나타나 외장재로서의 사용이 가능한 것으로 나타났다. 또한 제조한 외장재의 중금속 용출실험결과 환경적으로 안전한 것으로 나타났다.