• 한국세라믹학회지
• /
• 제52권2호
• /
• pp.92-102
• /
• 2015

Current plans for legacy nuclear wastes stored in underground tanks at the U.S. Department of Energy's Hanford Site in Washington are that they will be separated into high-level waste and low-activity waste fractions that will be vitrified separately. Formulating optimized glass compositions that maximize the waste loading in glass is critical for successful and economical treatment and immobilization of these nuclear wastes. Glass property-composition models have been developed and applied to formulate glass compositions for various objectives for the past several decades. Property models with associated uncertainties combined with composition and property constraints have been used to develop preliminary glass formulation algorithms designed for vitrification process control and waste-form qualification at the planned waste vitrification plant. This paper provides an overview of the current status of glass property-composition models, constraints applicable to Hanford waste vitrification, and glass formulation approaches that have been developed for vitrification of hazardous and highly radioactive wastes stored at the Hanford Site.

• 한국세라믹학회지
• /
• 제40권10호
• /
• pp.936-942
• /
• 2003

In order to develop glass formulations for vitrifying Low-and Intermediate-Level radioactive Wastes (LILW) from nuclear power plants of Korea Hydro & Nuclear Power (KHNP) Co., Ltd., promising glass formulations were selected based on glass property model predictions for viscosity, electrical conductivity and leach resistance. Laboratory measurements were conducted to verify the model predictions. Based on the results, the models for electrical conductivity, US DOE 7-day Product Consistency Test (PCT) elemental release, and pH of PCT leachate are accurate for the LILW glass formulations. However, the model for viscosity was able to provide only qualitative results. A leachate conductivity test was conducted on several samples to estimate glass leach resistance. Test results from the leachate conductivity test were useful for comparison before PCT elemental release results were available. A glass formulation K11A meets all the KHNP glass property constraints, and use of this glass formulation on the pilot scale is recommended. Glass formulations K12A, K12B, and K12E meet nearly all of the processing constraints and may be suitable for additional testing. Based on the comparison between the measured and predicted glass properties, existing glass property models may be used to assist with the LILW glass formulation development.

• 방사성폐기물학회지
• /
• 제10권4호
• /
• pp.247-254
• /
• 2012

원전에서 발생되는 방사성폐기물에 대한 고화처리 방법 중 하나인 유리화기술이 일부 가연성폐기물에 대해 적용되고 있다. 국내외적으로 중저준위 방사성폐기물의 효과적인 감용과 안정적인 처분을 위해 다양한 폐기물에 대한 유리화기술 적용방안이 확대 연구되고 있으며, 최근에는 가연성폐기물 뿐만 아니라 알루미늄 금속과 같은 비가연성폐기물에도 유리화 연구가 활발하게 진행되고 있다. 공기조화계통 (HVAC)에는 주로 필터가 이용되고 있으며, 사용 후 필터는 여과재 (유리섬유 및 알루미늄)를 이용하여 배기체를 흡착하기 때문에 방사성폐기물로 처리가 되어야 한다. 본 연구는 필터에 대한 처리기술 연구를 위해 유도가열식 저온용융로 (Cold Crucible Induction Melter: CCIM)를 이용한 유리화 타당성 연구를 수행하였다. 사용후 필터에 대한 유리화 (Vitrification)는 먼저 유리섬유 및 알루미늄 함량을 고려한 최적의 유리조성을 개발 하였으며, 개발된 유리 조성을 이용하여 최적의 폐기물 저감을 위한 용융변수와 최종 생성된 유리고화체의 특성을 분석하였다. 사용후 필터 유리화용 조성유리는 주로 $SiO_2$와 $B_2O_3$로 구성되어 있다. 전기로를 이용한 용융물 특성시험에서는 폐기물 투입률 및 최종 생성물인 유리고화체의 특성이 검토되었다. 본 연구에서는 알루미늄 금속과 유리섬유로 구성된 필터에 대한 유리조성 개발과 이를 통해 생성된 유리고화체의 물리화학적 특성을 검토하고 유리화 타당성을 확인하였다.

• Computers and Concrete
• /
• 제19권2호
• /
• pp.127-131
• /
• 2017

This paper presents a generalized formulation for optimizing the design of concrete beam reinforced with glass fiber reinforced polymer bar. The optimization method is formulated to find the design variables leading to the minimum weight of concrete beam with constraints imposed based on ACI code provisions. A simple genetic algorithm is utilized to solve the optimization task. The weights of concrete and glass fiber reinforced polymer bar are included in the formulation of the objective function. The ultimate limit states and the serviceability limit states are included in formulation of constraints. The results of illustrated example demonstrate the efficiency of the proposed method to reduce the weight of beam as well as to satisfy the above requirement. The application of the optimization based on the most economical design concept have led to significant savings in the amount of the component materials to be used in comparison to classical design solutions.

• Journal of Radiation Protection and Research
• /
• 제29권1호
• /
• pp.33-39
• /
• 2004

In order to vitrify the W1 waste (ion-exchange resin(IER), zeolite, and dry active waste(DAW)) generated from Korean Nuclear Power Plants, a glass formulation development based on waste compositions and production rates was performed. A aluminoborosilicate glass, AG8W1, was formulated to vitrify the W1 waste in an induction cold crucible melter(CCM). The processability, product performance, and economics of the candidate glass were calculated using a computer code and were measured experimentally in the laboratory and CCM. The glass viscosity and electrical conductivity as the process parameters were in the desired ranges. Start-up and maintaining glass melt of the candidate glass were favorable in the CCM. The product quality of the glass such as chemical durability, phase stability, etc. was satisfactory. The vitrification process using the candidate glass was also evaluated to be operated as economically as possible.

• 방사성폐기물학회지
• /
• 제2권3호
• /
• pp.175-180
• /
• 2004

In order to vitrify the combustible dry active waste (DAW) generated from Korean Nuclear Power Plants, a glass formulation development based on waste composition was performed. A borosilicate glass, DG-2, was formulated to vitrify the DAW in an induction cold crucible melter (CCM). The processability, product performance, and volume reduction effect of the candidate glass were evaluated using a computer code and were measured experimentally in the laboratory and CCM. The glass viscosity and electrical conductivity as the process parameters were in the desired ranges. Start-up and maintaining glass melt of the candidate glass were favorable in the CCM. The product of the glass product such as chemical durability, phase stability, and density was satisfactory. The vitrification process using the candidate glass was also evaluated assuming that it was operated as economically as possible.

• Earthquakes and Structures
• /
• 제8권1호
• /
• pp.101-132
• /
• 2015

This research formulates a closed-form equation to predict a glass panel cracking failure drift for several curtain wall and storefront systems. An evaluation of the ASCE 7-10 equation for Dclear, which is the drift corresponding to glass-to-frame contact, shows that the kinematic modeling assumed for formulation of the equation is sound. The equation proposed in this paper builds on the ASCE equation and offers a revision of that equation to predict drift corresponding to cracking failure by considering glazing characteristics such as glass type, glass panel configuration, and system type. The formulation of the proposed equation and corresponding analyses with the ASCE equation is based on compiled experimental data of twenty-two different glass systems configurations tested over the past decade. A final comparative analysis between the ASCE equation and the proposed equation shows that the latter can predict the drift corresponding to glass cracking failure more accurately.

• 생약학회지
• /
• 제45권3호
• /
• pp.249-255
• /
• 2014

This study compared Bojungikgi-tang (BIT) and Yukmijihwang-tang (YJT) decoctions produced using the extractors made of various materials, such as glass, earthenware, and stainless steel, for 60, 90, and 120 min. The extraction yield was measured and the amounts of marker compounds in decoctions were determined by quantitative analysis using high performance liquid chromatography. The extraction yields of BIT decoctions produced by three extractors were not significantly different, whereas the extraction yield of YJT produced using glass extractor was significantly higher than that of YJT produced using earthenware extractor after 90 min. The amounts of most marker compounds were highest in BIT decoctions produced using glass extractor. However, variations of the amounts of marker compounds were observed in YJT decoctions and the volatile compound was not easily vaporized in YJT decoction produced using earthenware extractor. This study suggests that the extractor made of various materials may affect the extraction efficiency and the contents of marker compounds, especially in the decoction produced using earthenware extractor, although the results were dependent on the characteristics of herbal formula.

• 방사성폐기물학회지
• /
• 제8권2호
• /
• pp.143-150
• /
• 2010

가압경수로 원전의 농축폐액건조설비에서 발생된 농축폐액 건조물을 유리화 하는 방안이 연구되어 왔다. 중저준위 방사성폐기물을 유리화할 경우 최종 생성물은 내구성이 우수하고 현저한 부피저감 효과의 장점을 가지고 있다. 붕산농축폐액에 대한 유리화 타당성 연구는 분말시료의 전처리 방법 개발, 유리조성 프로그램을 이용한 유리개발 및 실증시험으로 수행되었다. 분말시료에 대한 전처리 방안으로는 유리화설비에 투입하기 전에 고형성을 갖도록 펠렛화하는 것이다. 농축폐액 성분중 Na와 B의 함량 분포는 유리속에 용융되는 정도와 설비로부터의 폐기물 배출 처리에 영향을 주기 때문에 이를 고려하여 유리조성이 개발되어야 한다. 실증시험에서는 폐기물 투입률, 배기체 특성 및 최종 생성물인 유리고화체의 특성이 검토되었다. 본 연구는 붕산농축폐액에 대한 유리고화체의 물리화학적 특성을 검토하고 유리화 타당성을 확인하는데 목적이 있다.

• 한국세라믹학회지
• /
• 제38권9호
• /
• pp.839-845
• /
• 2001

원자력발전소에서 발생하는 폐수지, 잡고체, 붕산폐액을 유리화 하기 위하여 폐기물별 조성을 바탕으로 유리조성 연구를 수행하였다. 폐수지, 잡고체를 각각 유리화 할 수 있는 두 개 의 후보유리 RG-1과 DG-1 그리고 폐수지, 잡고체, 붕산폐액을 혼합하여 처리할 수 있는 후보유리 MG-1을 개발하였다. 각 후보유리에 대해 운전변수, 고화체 품질, 가용 효과를 평가하였으며 일부 특성들은 실험실적으로 확인하였다. 운전 변수 가운데 유리의 점도와 전기 전도도는 세 후보유리 모두 적정운전 범위값 내에 만족하였으며 밀도, 화학적 견고성, 상안정성 등 고화체의 품질 또한 우수하였다. 개발한 유리 조성 연구를 바탕으로 폐수지, 잡고체, 혼합폐기물을 유리화 할 경우 감용비는 각각 21, 89, 75로 평가되었다.