• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.516-522
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• 2023

The co-precipitation process plays a key role in the decontamination of radionuclides from low and intermediate levels of liquid waste. For that reason, the removal of Cs ions from waste solution by the co-precipitation method was carried out. A simulated liquid waste (¹³³Cs) was prepared from a 0.1 M CsCl solution, while wastewater generated by washing steel ash served as a representative of radioactive cesium solution (¹³⁷Cs). By co-precipitation, potassium ferrocyanide was applied for the adsorption of Cs ions, while nickel nitrate and iron sulfate were selected for supporting the precipitation. The amount of residual Cs ions in the CsCl solution after precipitation and filtration was determined by ICP-OES, while the radioactivity of ¹³⁷Cs was measured using a gamma-ray spectrometer. After cesium removal, the amount of cesium appearing in both XRD and SEM-EDS was analyzed. The removal efficiency of ¹³³Cs was 60.21% and 51.86% for nickel nitrate and iron sulfate, respectively. For the ash-washing solution, the removal efficiency of ¹³⁷Cs was revealed to be more than 99.91% by both chemical agents. This implied that the co-precipitation process is an excellent strategy for the effective removal of radioactive cesium in waste solution treatment.

• Journal of the Korean Professional Engineers Association
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• v.31 no.3
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• pp.45-48
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• 1998

• Journal of Radiation Protection and Research
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• v.29 no.1
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• pp.1-8
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• 2004

Diphosil, a new version of the organic-inorganic composite resin developed by ANL has a structure of the chelating diphosphonic acid groups grafted to a silica support. To apply Diphosil for the treatment of liquid radioactive waste from nuclear power plants, the adsorption equilibrium and column experiments were carried out for the main radionuclides, $^{137}Cs\;and\;^{60}Co$, in the liquid radwaste stream. Through the adsorption equilibrium experiments, the removal efficiencies of $^{137}Cs\;and\;^{60}Co$, and the effects of non-radioactive ions on the removal efficiency have been measured in various conditions using radiotracers. The breakthrough curves for the tested tracers were obtained from the laboratory scale column tests using the simulated liquid radioactive waste. In addition, the removal capacity of Diphosil is compared with that of Amberlite IRN 77 resin, generally used in nuclear power plants.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2011.10a
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• pp.321-322
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• 2011

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.296-300
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• 2001

In order to recycle the incineration ash (bottom ash and fly ash) generated from the incineration of municipal waste for a cement material, salts as well as heavy metal should be removed by the stabilization treatment. Most of these heavy metal and over 80% of salts are removed by a washing as a pre-treatment. However, wastewater which is another pollutant is generated by a washing, then proper treatment should be developed. First the characteristics of incineration ashes collected from two domestic full-sized incinerators were investigated and removal rate of salts and heavy metals from them also studied. The wastewater quality was compared to the criteria of the regulation by analyzing the characteristics of generated wastewater during the washing of incineration ash as a condition of liquid/solid ratio. Also, we tried to used this experimental results for the basic data to develop proper processing technique of municipal waste.

• Journal of the Korean Ceramic Society
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• v.29 no.1
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• pp.15-22
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• 1992

The reason for permanent shrinking of recycled castable refractories from alumino-silicate waste refractories was investigated and the method to control shrinking is suggested in order to increase maximum service termperature. The porosity of castable refractories with waste material as large aggregate decreases after heat treatment because the porosity of waste refractories is greater than the of green material, in which CaO around large aggregate penetrates into aggregate and promotes liquid phase sintering. The shrinking of recycled castable refractories resulted in the decrease in porosity can be controled by addition of green kaolin chamotte as large aggregate. The shrinking of recycled castable refractories caused by the differences in densities of mineral phases before and after heat treatment can be controled by addition of kyanite. The use of green kaolin chamotte and kyanite increases the service temperature of recycled castable refractories up to 1500$^{\circ}C$.

• Membrane and Water Treatment
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• v.9 no.5
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• pp.327-334
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• 2018

The nano/micro composites with highly porous surface area have attracted of great interest, particularly the synthesis of porous and thin film sheets of high performance. In this paper, an easy method of cost-effective synthesis of thin film ceramic fiber membranes based on Hydroxyapatite, and activated carbon by turned into studied to be applied within the service-facilitated the transport of radioactive waste such as $^{90}Sr$, $^{137}Cs$ and $^{60}Co$) as activated product of radioisotopes from ETRR-2 research reactor and dissolved in 3M $HNO_3$, across a thin flat-sheet supported liquid membrane (TFSSLM). Radionuclides are transported from alkaline pH values. The presence of sodium salts in the aqueous media improves in $HNO_3$, the lowering of permeability because the initial $HNO_3$ concentration is improved. The study some parameters on the thin sheet ceramic supported liquid membrane. EDTA as stripping phase concentration, time of extraction and temperature were studied. The study of maximum permeability of radioisotopes for all parameters. The pertraction of a radioactive waste solution from nitrate medium were examined at the optimized conditions. Under the optimum experimental 98.6-99.9% of $^{90}Sr$, 79.65-80.3% of $^{137}Cs$ and $^{60}Co$ 45.5-55.5% in 90-110 min with were extracted in 10-30 min, respectively. The process of diffusion in liquid membranes is governed by the chemical diffusion process.

• Advances in environmental research
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• v.2 no.2
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• pp.131-141
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• 2013

Agricultural practice and improper waste disposal in developing regions have resulted in environmental degradation in land and waters, for which low-cost, proven solutions are needed. We demonstrate in the laboratory the applications of composting and trickling filter techniques to treat olive mill wastes that can be implemented in the West Bank and other regions of the world. To a pomace waste sample from a California mill, we amended with saw dust (wood carbon source) and baking soda ($NaHCO_3$ alkalinity) at weight ratios of waste/wood/$NaHCO_3$ at 70:27:1 and composted it for periods of 11 and 48 days; the compost was used as an additive to potting soil for transplanting. The pomace sample was also blended into slurry and introduced to a water-circulating pond and trickling filter system (P/TF) to examine any inhibitive effect of the pomace on biological removal of the organic waste. The results showed the compost-amended potting soil supported plant growth without noticeable stress over 34 days and the P/TF system removed BOD and COD by >90% from the waste liquid within 2 days, with a first-order rate constant of 1.9 $d^{-1}$ in the pond. An onsite treatment design is proposed that promises implementation for agricultural waste disposal in developing regions.

• Journal of Animal Environmental Science
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• v.18 no.sup
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• pp.7-12
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• 2012

To prevent the inappropriate treatment of livestock manure and induce the correct circulation of them into farmland, systematic monitoring and management by the treatment and circulation stage of livestock manure are required. The purpose of this study was to apply ubiquitous information communictation technology (u-ICT) to a livestock waste management system for better treatment by utilizing ubiquitous computing technology in the livestock sector. Elements and levels of applicable u-ICT technology for efficient livestock manure management were derived by analyzing previous researches. In addition, a conceptual diagram of an integrated management system was suggested by analyzing the existing liquid fertilization process.

• Microbiology and Biotechnology Letters
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• v.3 no.3
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• pp.117-122
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• 1975

In order to develop an activated sludge which can be used for both waste treatment and protein source of animal feed, microorganisms were isolated from sewages of various wheat or sweet potato starch processing plants and their activities were tested. Out of 32 isolates which composed of two protozoan genera and 13 bacterial strains, were screened and three bacterial stranis were found to be most effective in both floe-formation and wheat starch waste liquid stabilization.