• 공업화학
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• 제17권4호
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• pp.391-396
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• 2006

방사성 폐기물을 시멘트로 고화처리는 농축 폐액 내의 붕산으로 인해 시멘트의 양생을 지연시키며 감용비가 낮아지는 현상을 나타낸다. 본 연구에서는 이러한 단점을 보완하기 위하여 파라핀 왁스로 처리하여 감용 효과를 높이는 연구를 수행하였다. 파라핀 왁스는 소수성이 커서 무기물과의 혼합특성이 좋지 않아 층 분리 현상이 일어날 수 있다. 왁스의 양이 적은 경우 고화체의 압축강도가 낮아짐을 알 수 있었다. 따라서 먼저 폐기물의 붕산성분을 알칼리염으로 처리하고 이것을 stearic acid로 코팅처리 하였다. 파라핀 왁스로 고화처리 시 왁스의 함량을 일정이상 유지하면 시멘트로 처리한 고화체의 압축강도로 향상되었고 파라핀 고화체의 침출특성에서 파라핀 왁스를 20% 및 25% 함유한 고화체는 CFL (cumulative fraction leached), PR (penetration rate), 유효확산계수 등이 비숫한 값을 지닌다.

• 방사성폐기물학회지
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• 제21권4호
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• pp.465-479
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• 2023

To ensure the safety of disposal facilities for radioactive waste, it is essential to quantitatively evaluate the performance of the waste disposal facilities by using safety assessment models. This paper addresses the development of the safety assessment model for the underground silo of Wolseong Low-and Immediate-Level Waste (LILW) disposal facility in Korea. As the simulated result, the nuclides diffused from the waste were kept inside the silo without the leakage of those while the integrity of the concrete is maintained. After the degradation of concrete, radionuclides migrate in the same direction as the groundwater flow by mainly advection mechanism. The release of radionuclides has a positive linear relationship with a half-life in the range of medium half-life. Additionally, the solidified waste form delays and reduces the migration of radionuclides through the interaction between the nuclides and the solidified medium. Herein, the phenomenon of this delay was implemented with the mass transfer coefficient of the flux node at numerical modeling. The solidification effects, which are delaying and reducing the leakage of nuclides, were maintained the integrity of the nuclides. This effect was decreased by increasing the half-life and the mass transfer coefficient of radionuclides.

• 한국환경보건학회지
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• 제30권5호
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• pp.388-394
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• 2004

Seaweed waste(SWW) was used to improve the liner effect in recycling of dredged soil as the landfill liner. It was found that the compressive strength became somewhat lower when SWW was added than that was when Ordinary Port-land Cement(OPC) only was added. The permeability coefficient, however, became lower in this case which showed the lowest permeability coefficient when the addition of SWW was one percent. Hence, to comply with the regulations for the compression strength and permeability coefficient of landfill liner, the addition of OPC should be over eight percent and that of seaweed waste one percent. The results of leaching test showed that the solidified material was not against the laws of waste control, so it is possible to use as the landfill liner and to expect sufficient economic effects because wastes such as dredged soil and seaweed can be recycled.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.32-37
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• 2003

한국원자력연구소에서 약 4,500드럼 규모의 토양폐기물을 임시로 보관하고 있다. 이를 안전하게 처리하기 위한 고화기술 개발이 필요함에 따라 시멘트와 폴리머를 선정하여 시험을 수행하였다. 이를 위해 토양폐기물에 시멘트와 폴리머를 적절히 혼합하여 고화시편을 제조하였으며, 저장에 따른 처분기준 만족여부를 평가하기 위하여 압축강도시험과 침출시험을 수행하였다. 폐기물함량이 40%인 시멘트고화체와 65%인 폴리머고화체의 압축강도가 약 5,300psi로서 유사하였으며, 침출지수는 11 이상으로서 모든 시편에서 기준치를 만족하였다. 고화과정의 균질한 혼합여부와 시편의 다짐상태가 고화체의 건전성에 큰 영향을 미치는 것으로 확인되었다. 감용효과는 폴리머고화체가 시멘트고화체에 비해 20% 정도 우수한 것으로 평가되었다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 춘계학술논문요약집
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• pp.202-203
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• 2018

• 한국압력기기공학회 논문집
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• 제7권4호
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• pp.26-30
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• 2011

In order to ship low & Intermediate level radioactive waste drums, which have been temporarily stored on site, to a disposal facility, their physical and chemical properties should be evaluated and proven to meet the acceptance guideline prior to their shipment. Ultrasonic velocity method, which has been used to estimate the strength of concrete, can be suggested to evaluate the compressive strength of solidified radioactive waste, which is one of the evaluated properties. The strength is estimated from acoustic velocity. However, a guided wave traveling along a drum is generated when applying ultrasonic method to the drum, and this makes it difficult to analyze the signal due to overlap between transmitted wave through the contents in drum and the guided wave. This paper reported feasibility of ultrasonic method to evaluate of the compressive strength of the solidified LLW. It is observed that the guide wave is greater than transmitted wave, and ultrasonic velocity could be estimated from transmitted wave signal arriving prior to the guided wave

• 유기물자원화
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• 제11권2호
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• pp.66-73
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• 2003

석유화학공장폐수 슬러지를 폐석고와 시멘트, fly ash 및 고화제 등을 배합하여 성형하면 시멘트벽돌 및 보통시멘트의 압축강도 기준을 초과함으로 제조된 고화체는 벽돌, 블록, 경량골재, 노반재 등으로 활용이 가능할 것으로 판단되었다. 실험 결과 다음의 결과를 얻었다. 시멘트량을 전체 중량비의 20%인 1.29kg에서 fly ash/슬러지의 배합비의 모든 조건과 시멘트량을 전체 중량비의 15%인 0.9kg에서 fly ash/슬러지의 배합비가 0.31~0.45일 때, 시멘트벽돌 및 보통시멘트의 압축강도 기준을 초과하였다. 제조된 고화체(제품)의 유해성 평가를 위해서 침출수 중의 $Cr^{+6}$, Cu, Zn, Cd, Pb의 용출농도를 실시한 결과 모든 대상시료의 중금속 농도는 배출허용기준치 이내를 유지하여 유해물질로 인한 문제는 없을 것으로 판단되었다. 고화체를 시멘트벽돌 및 보통시멘트에 준해서 활용이 가능한 제조조건에서 제조원가를 조사하였다. 조사결과 자원화시설의 고화체 제조능력을 연간 약 18,000톤을 기준으로 할 때, 총괄원가 및 톤당제조원가는 각각 678,664천원 및 37,704원으로 조사되었다.

• Nuclear Engineering and Technology
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• 제35권5호
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• pp.482-496
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• 2003

effectiveness of the PAM graphite-electrode technology for the treatment of many types of low-level radioactive waste including : combustible material, solidified resins in cement, inorganic materials, steel, glass, and solidified boric acid cement. The objectives of PAM-200 evaluation were to verify that 1) the facility meets air emission regulations, 2) the facility can be safely operated when processing hazardous and radioactive materials and 3) satisfactory final waste forms can be produced. Results, derived from KAERI's(Korea Atomic Energy Research Institute) analyses for samples of vitrified product, scrubbing solution and offgas collected during test period, show that PAM-200 can treat radioactive wastes as well as hazardous wastes with toxic constituents and radionuclides contained in the offgas exiting from the stack to the environment controlled to be far lower than the limit regulated by air conservation law and atomic law.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제2권1호
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• pp.9-19
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• 1998

A laboratory study was conducted to investigate the immobilization of the laboratory waste sludge, mainly from chemical oxygen demand (COD) waste, using cementitious binders. The binders were: Ordinary Portland Cement (OPC), and lime-Rice Husk Ash(RHA) cement. The economic evaluation was done for three different kinds of cementitious binders, namely, OPC, Portalnd Rice Husk Ash Cement (PRHAC) which contained rice husk ash 50 percent by dry weight, and lime-RHA cement. The result showed that lime-RHA cement was the cheapest. The applicability of Freundlich's desorption isotherm was studied to assess the teachability of sludges. The teachability of cement mortars was found to follow the desorption isotherms. Therefore, it was concluded that based on this test, the leachate concentrations of the solidified heavy metals could be predicted, approximately by the Freundlich's isotherm desorption modeling.

• 한국환경과학회지
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• 제2권1호
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• pp.9.2-19
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• 1993

A laboratory study was conducted to investigate the immobilization of the laboratory waste sludge, mainly from chemical oxygen demand (COD) waste, using cementitious binders. The binders were: Ordinary Portland Cement (OPC), and lime-Rice Husk Ash (RHA) cement. The economic evaluation was done for three different kinds of cementitious binders, namely, OPC, Portaind Rice Husk Ash Cement (PRHAC) which contained rice husk ash U percent by dry weight, and lime-RHA cement. The result showed that lime-RHA cement was the cheapest. The applicability of Freundlich's desorption isotherm was studied to assess the teachability of sludges. The teachability of cement mortars was found to follow the desorption isotherms. Therefore, it was concluded that based on this test, the leachate concentrations of the solidified heavy metals could be predicted, approximately by the Freundlich's isotherm desorption modeling.