• Nuclear Engineering and Technology
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• v.45 no.5
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• pp.675-682
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• 2013

The sequential separation process, composed of an oxygen sparging process for separating lanthanides and a zone freezing process for separating Group I and II fission products, was evaluated and tested with a surrogate eutectic waste salt generated from pyroprocessing of used metal nuclear fuel. During the oxygen sparging process, the used lanthanide chlorides (Y, Ce, Pr and Nd) were converted into their sat-insoluble precipitates, over 99.5% at $800^{\circ}C$; however, Group I (Cs) and II (Sr) chlorides were not converted but remained within the eutectic salt bed. In the next process, zone freezing, both precipitation of lanthanide precipitates and concentration of Group I/II elements were preformed. The separation efficiency of Cs and Sr increased with a decrease in the crucible moving speed, and there was little effect of crucible moving speed on the separation efficiency of Cs and Sr in the range of a 3.7 - 4.8 mm/hr. When assuming a 60% eutectic salt reuse rate, over 90% separation efficiency of Cs and Sr is possible, but when increasing the eutectic salt reuse rate to 80%, a separation efficiency of about 82 - 86 % for Cs and Sr was estimated.

• Nuclear Engineering and Technology
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• v.40 no.3
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• pp.175-182
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• 2008

The results of process development for the blending of waste salt from the electrorefining of spent fuel with zeolite-A are presented. This blending is a key step in the ceramic waste process being used for treatment of EBR-II spent fuel and is accomplished using a high-temperature v-blender. A labscale system was used with non-radioactive surrogate salts to determine optimal particle size distributions and time at temperature. An engineering-scale system was then installed in the Hot Fuel Examination Facility hot cell and used to demonstrate blending of actual electrorefiner salt with zeolite. In those tests, it was shown that the results are still favorable with actinide-loaded salt and that batch size of this v-blender could be increased to a level consistent with efficient production operations for EBR-II spent fuel treatment. One technical challenge that remains for this technology is to mitigate the problem of material retention in the v-blender due to formation of caked patches of salt/zeolite on the inner v-blender walls.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.1
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• pp.1-10
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• 2018

A simplified flowsheet for pyroprocessing commercial spent fuel is proposed in which the only salt treatment step is actinide drawdown from electrorefiner salt. Actinide drawdown can be performed using a simple galvanic reduction process utilizing the reducing potential of gadolinium metal. Recent results of equilibrium reduction potentials for Gd, Ce, Nd, and La are summarized. A description of a recent experiment to demonstrate galvanic reduction with gadolinium is reviewed. Based on these experimental results and material balances of the flowsheet, this new variant of the pyroprocessing scheme is expected to meet the objectives of minimizing cost, maximizing processing rate, minimizing proliferation risk, and optimizing the utilization of geologic repository space.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.133-138
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• 2005

The worldwide trend of waste treatment technology is rapidly transferring from "incineration system" to "gasification & melting system" which can derive the resources from waste and charge no more environmental burden to nature. And therefore it is necessary to adopt gasification & melting system to prevent the land pollution and to solve the problem of landfill area. Among several thermal waste treatment processes gasification and melting system is the representative process which can transfer waste to resources such as syn-gas, molten slag, metal hydroxide, mixed salt and sulfur through the process of compaction, pyrolysis, gasification and melting.

• Environmental Analysis Health and Toxicology
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• v.16 no.2
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• pp.103-114
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• 2001

Worldwide trend of waste treatment technology is rapidly transferring from "incineration system" to "gasification & melting system" which can derive the resources from waste and charge no more environmental burden to nature. And therefore it is necessary for our country to adopt gasification & melting system urgently to present the land pollution and lack of landfill area. Among several gasification and melting processes Daewoo-Thermoselect gasification and melting system is the representative process which can transfer waste to resources such as sin-gas, molten slag, metal hydroxide, mixed salt and sulfur through the process of compaction, degasification, gasification and melting.

• Korean Journal of Agricultural Science
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• v.42 no.3
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• pp.177-181
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• 2015

Food waste has been widely considered as a recycling resource to be applied to agricultural lands due to the effects of organic matter and nutrient for plant productivity. but the maturity and salt concentration in the compost produced from food waste processing facilities should be considered firstly, which was little information on compost quality produced from food waste treatment facility. In this study, we examined actual situation of food waste processing facility on the composting of food waste and evaluated the characteristics of composts produced from food waste processing facilities. The quality of composts was analyzed on the basis of the criteria of fertilizer processing manual. The 46% of food waste treatment facility registered composting produced actually the compost mixed with food waste or animal waste. The compost maturity and salt concentration as indicators of the quality of compost were not met 46.8% of composts collected from food waste processing facilities to the criteria of fertilizer processing manual. Also, 15.6%(moisture) were not satisfied with the criteria. In conclusion, the compost produced from food waste processing facilities is firstly required with better compost maturity and reduced salt concentration in order to use to agricultural lands as an amendment.

• Journal of Advanced Engineering and Technology
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• v.6 no.2
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• pp.125-129
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• 2013

In the pyrochemcial process of spent nuclear fuel, it is necessary to separate rare earth nuclides from LiCl-KCl eutectic waste salt for radioactive waste reduction. This paper presents the phosphorylation of neodymium chloride in LiCl-KCl-NdCl₃ system using Li₃PO₄-K₃PO₄ as a phosphorylation agent in a chemical reactor with pitched blade impellers. The phosphorylation test was performed changing operation temperature, stirring rate, and amount of phosphorylation agent. Neodymium chloride was effectively converted into neodymium phosphate (NdPO₄). It was confirmed that more than 99 wt% of neodymium can be separated from LiCl-KCl-NdCl₃ system using a phosphorylation method l

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.3
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• pp.279-298
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• 2019

This study comprehensively addresses recent progress at KAERI in waste treatment technology to cope with waste produced by pyroprocessing, which is used to effectively manage spent fuel. The goal of pyroprocessing waste treatment is to reduce final waste volume, fabricate durable waste forms suitable for disposal, and ensure safe packaging and storage. KAERI employs grouping of fission products recovered from process streams and immobilizes them in separate waste forms, resulting in product recycling and waste volume minimization. Novel aspects of KAERI approach include high temperature treatment of spent oxide fuel for the fabrication of feed materials for the oxide reduction process, and fission product concentration or separation from LiCl or LiCl-KCl salt streams for salt recycling and higher fission-product loading in the final waste form. Based on laboratory-scale tests, an engineering-scale process test is in progress to obtain information on the performance of scale-up processes at KAERI.

• Membrane and Water Treatment
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• v.10 no.2
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• pp.139-148
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• 2019

In this study, the removal of MB from saline solutions was evaluated by two methods by adsorption and electrodialysis; the adsorption of the mixture dye/salt on dried orange peel waste (OPW) was studied in batch method. In this study the biosorption of cationic dye by OPW was investigated as a function of initial solution pH, and initial salt (sodium chloride) concentration. The maximal dye uptake at $pH{\geq}3.6$ in the absence and in the presence of salt and the dye uptake diminished considerably in the presence of increasing concentrations of salt up to 8 g/L. The Redlich Peterson and Langmuir were the most suitable adsorption models for describing the biosorption equilibrium data of the dye both individually and in salt containing medium. As well, this work deals with the electrodialysis application to remove the dye. Synthetic solutions were used for the investigation of the main operational factors affecting the treatment performance; such as applied voltage, pH, initial dye concentration and ionic strength. The experimental results for adsorption and electrodialysis confirmed the importance of electrostatic interactions on the dye. The electrodialysis process with standard ion exchange membranes enabled efficient desalination of cationic dye solutions; there are two main factors in fouling: electrostatic interaction between cations of dyes and the fixed charged groups of the CEM, and affinity interactions.

• Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.349-357
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• 2015

To reutilize fisheries waste, we isolated a bacterial strain from a coastal area located in Busan. It was identified as Bacillus licheniformis TK3-Y. Using plate assay and 500-mL flask experiments, we found that the isolate simultaneously possessed cellulolytic, proteolytic, and lipolytic activities with salt tolerance. 10% (v/v) inoculums, were used to examine the biodegradation characteristics of the TK3-Y strain on carboxymethylcellulose, skim milk, and olive oil media. The optimum conditions for pH, temperature, agitation speed, and NaCl concentration on each 1% substrate were 6, $50^{\circ}C$, 180 rpm, and 17.5%, respectively. Under optimal conditions, the TK3-Y strain showed 1.07 U/mL cellulolytic, 1,426 U/mL proteolytic, and 6.45 U/mL lipolytic activities. Each enzyme was stable within a range of 17.5-35% NaCl. Therefore, the salt tolerance ability of strain TK3-Y was superior to other related strains. In degradation of a mixed medium containing all three substrates, both the cellulolytic and proteolytic activities were somewhat lower than those on each single substrate, while the lipolytic activity was somewhat higher. From the above results, the TK3-Y strain appears to be a good candidate for use in the efficient treatment of fisheries waste in which components are not collected separately.