• Nuclear Engineering and Technology
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• v.44 no.8
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• pp.945-952
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• 2012

The sorption of selenium ions onto iron and iron compounds as a disposal container material and its corrosion products, and onto bentonite as a buffer material, was studied to understand the behaviors of selenium in a waste repository. Selenite was sorbed onto commercial magnetite very well in solutions at around pH 9, but silicate hindered their sorption onto both magnetite and ferrite. Unlike commercial magnetite and ferrite, flesh synthesized magnetite, green rust and iron greatly decreased selenium concentration even in a silicate solution. These results might be due to the formation of precipitates, or the sorption of selenide or selenite onto an iron surface at below Eh= -0.2 V. Red-colored Se(cr) was observed on the surface of a reaction bottle containing iron powder added into a selenite solution. Silicate influences on the sorption onto magnetite and iron for selenide are the same as those for selenite. Even though bentonite adsorbed a slight amount of selenite, the sorption cannot be ignored in the waste repository since a very large quantity of bentonite is used.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.1041-1046
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• 2019

In terms of long-term safety for radioactive waste disposal, the anionic iodide (I-129) with a long half-life ($1.6{\times}10^6yr$) is of a critical importance because this radionuclide migrates in geological media with limited interactions. Various studies have been performed to retard the iodide migration. Recently, some minerals that are likely generated from waste container corrosion, have been suggested to have a considerable chemical interaction with iodide. In this study, chalcocite and mackinawite were selected as candidate minerals for underground corrosion materials, and an iodide sorption experiment were carried out. The experiment was performed under anoxic and alkaline conditions and the pH effects on the iodide sorption were investigated in the range of pH 8 to 12. The results showed that both minerals demonstrated a noticeable sorption capacity on iodide, and the distribution coefficient ($K_d$) decreased as the pH increased in the experimental condition. In addition, when the alkalinity increased higher than a pH of 12, the sorption capacity of both minerals decreased dramatically, likely due to the competition of hydroxy ions with the iodide. This result confirmed that chalcocite was an especially good sorbing media for iodide under alkaline conditions with a pH value of less than 12.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.4
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• pp.503-516
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• 2023

A transfer cask serves as the container for transporting and handling canisters loaded with spent nuclear fuels from light water reactors. This study focuses on a cylindrical transfer cask, standing at 5,300 mm with an external diameter of 2,170 mm, featuring impact limiters on the top and bottom sides. The base of the cask body has an openable/closable lid for loading canisters with storage modules. The transfer cask houses a canister containing spent nuclear fuels from lightweight reactors, serving as the confinement boundary while the cask itself lacks the confinement structure. The objective of this study was to conduct a structural analysis evaluation of the transfer cask, currently under development in Korea, ensuring its safety. This evaluation encompasses analyses of loads under normal, off-normal, and accident conditions, adhering to NUREG-2215. Structural integrity was assessed by comparing combined results for each load against stress limits. The results confirm that the transfer cask meets stress limits across normal, off-normal, and accident conditions, establishing its structural safety.

• Journal of agricultural medicine and community health
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• v.21 no.1
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• pp.97-105
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• 1996

This study conducted to determine the evaluation and improvement for enforcement of the waste recycling system in Pohang city and surveyed 4 areas at the southern and northern districts respectively by a team of two officials during the period 6 February 7 February 1995. The rates of the use for waste recycling system's envelope from home trash were 94.2% at the northern district and 92.8% at the southern district by areas, 95.6% at the group houses (apartments and tenement houses) and 91.3% at the separate houses by patterns of house, the low economic class 96.4%, the middle economic class 96.3% and the upper economic class 87.5% by the economic levels, and the bell method 96.5%, the container method 95.6%, door take method 86.1% in order, respectively. The trash from houses were garbage 57.4%, paper 18.7%, plastic 10.3%, fiber 7.9%, bottle 2.7%, metal and can 1.4%, and wood and rubber 0.7% in order. The rates of the reuse trash(reuse possible paper, plastic, bottle, can and metal) were 20.2% of the total, 21.8% at the southern district and 18.5% at the northern district by areas, 25.7% at the separate houses and 14.7% at the group houses(apartments and tenement houses) by patterns of house, and the door take method 34.3%, the bell take method 17.1% and the container take method 14.7% in order, respectively. There were the double envelopes of the plastic bag from stories 46.3% and the clear plastic bag 29.5% in the waste cycling system's envelopes. There were 1.9 double envelopes in the waste cycling system's envelopes. Garbage occupied more than half of the total trash, so it is need to be compost and provender.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.504-510
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• 2004

Two experiments were conducted. In expt. 1, a total of fifty-four pigs (L$\times$Y$\times$D, 56.14$\pm$1.7 kg) were used for a feeding trial to determine the effect of wet feeding of a commercial-type diet without food waste (FW). Treatments were dry (Control), wet (WF) and wet+dry feeding (WDF). For wet feeding, the diet was mixed with water at a ratio of 1:2.5 (feed:water). A wet feed was given during the whole experimental period for the WF group, but the dry feed was given during the finisher period for the WDF group. In expt. 2, a total of fifty-four pigs(L$\times$Y$\times$D, 55.7$\pm$1.8 kg) were used for a feeding trial to determine the effect of wet feeding of FW. Treatments were a commercial-type dry (Control), wet fermented food waste (WFFW) and WFFW+dry feeding (WFFW+DF). For wet feeding of fermented food waste, however, some ingredients (concentrate) were added to make nutrient contents comparable to the control diet. The FW collected was ground ($\leq$5 mm), heated with a steam jacket (140$\pm$3$^{\circ}C$) and fermented with probiotics for one day in a steel container at 30-40$^{\circ}C$. For the WFFW group, the wet feed was given during the whole experimental period, but a dry feed was given during finisher period for the WFFW+DF group. In expt. 1, during the grower period, pigs fed wet feed showed higher average daily gain (ADG) and feed conversion ratio (FCR) than those fed only dry feed (p<0.05). During the finisher period, pigs in the WDF group showed better ADG and FCR than the control group. During the entire experimental period, pigs in the WDF group grew faster (p<0.05) than those in the control group, and the same trend was found in FCR. Also, dressing percentage, backfat thickness, lean %, and pork color were not affected by the wet feeding of diets in this study. In expt. 2, during the grower period, pigs fed diets containing FW showed lower (p<0.05) ADG than those fed the control diet. But FCR was better (p<0.05) in pigs fed FW than in the control group. During the finisher period, pigs in the WFFW+DF group grew faster (p<0.05) than those in the control and WFFW groups. During the entire experimental period, pigs fed the control diet showed better ADG (p<0.05) than those fed FW, but feed intake and FCR were vice versa. Dressing percentage was lower (p<0.05) in the WFFW than in the control group, but backfat was thinner in the WFFW group than in the control group. In summary, it can be concluded that wet feeding of formula feed can improve daily gain, however, feeding fermented wet food waste may reduce daily gain of finishing pigs, even though it was fermented and the nutrient was fortified with concentrates. In addition, dry feeding of a formula feed during the finishing period can improve daily gain in pigs fed a wet feed with or without food waste during the grower period.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.3 no.1
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• pp.33-39
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• 1999

A two-dimensional numerical experiment and field observations were conducted to evaluate changes in sea water movement and the water quality environment related to comprehensive projects of waterfront development around Kwangyang Bay on the south coast of Korea. Tidal flow velocities, especially in the western part of the bay, were considerably slower as a result of the development projects. Accordingly, the seawater exchange ratio reduced from 38.7% to 26.3%. The impact of dredging work on the water quality environment was much stronger than expected. Furthermore, after the completion of the industrial parks and container-exclusive wharfs, COD from the waste water treatment plant will be dispersed extensively into the adjacent water at a level of less than 0.1 mg/l for up to 142.5 $\textrm{km}^2$. Therefore, consistent monitoring and management of the water quality environment is strongly recommended.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.1087-1093
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• 1996

Current processing and packaging of anchovy sauce was reviewed and a new method of anchovy sauce processing was proposed for standardized production and quality management. The proposed procedure for liquid type anchovy sauce involves mixing of anchovy fishes and salt(20%), stored aging and fermentation under controlled temperature condition, filtration/centrifuge, secondary fermentation and filtration of residue added with brine solution, combining of first and second filtrates, packaging into container, and pasteurization. Treatment of residue waste was also considered.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.1
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• pp.19-35
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• 2014

A parametric sensitivity to the annual exposure dose rate to the farming exposure group has been probabilistically carried out for three principal elements associated with the nuclide transport behavior in the near-field of the pyroprocessed waste repository system. Credit time for both metal and ceramic containers, annual nuclide release rete, and the degree of loss of bentonite buffer around the container are selected as the elements and investigated for important nuclides. All the elements are shown to be sensitive to the results. Methodology studied through this study and the results are expected to make a good feedback to the repository design. As a follow-up study, separated in Part 2, the A-KRS will be deterministically assessed and then compared among each other with the normal, the worst, and the best case scenarios associated with their extreme values these elements could have.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.475-479
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• 2011

Although the storage period of raw baechu cabbage could be 2 months at $0{\sim}2^{\circ}C$, 1 month was appropriate considering the quality of the baechu cabbage, waste ratio, and storage cost. The polyethylene container was the most efficient storage container among polypropylene box, polypropylene net and polyethylene container. pH of a brined baechu cabbage using raw baechu cabbage was 4.0~4.3 after 8 weeks and its total bacteria and lactic acid bacteria counts were $10^7$ cfu/g, and textural property (springiness) lower than 50% was at 8th week of storage at $0{\sim}2^{\circ}C$ and thus its storage period was limited to 8 weeks. When brined baechu cabbage was prepared by raw baechu cabbage stored for 1 month at $0{\sim}2^{\circ}C$, its pH, microorganism counts and springiness showed similar trends to the brined cabbage using raw baechu stored for 0 month. However, its rates of change were faster than the brined baechu cabbage using the raw baechu, and the storage period was limited to 6 weeks. Brined baechu cabbage using the raw cabbage stored for 2 months and its storage period was limited by about 4 weeks judging by its indicated quality characteristics.

• Progress in Medical Physics
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• v.25 no.1
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• pp.8-14
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• 2014

The amounts of radioactive wastes to be disposed in the medical institute have been increased due to development of radiation diagnosis and therapy rapidly. They are produced mostly by the very short lived radioisotopes such as $^{18}F$ used in PET/CT, $^{99m}Tc$, $^{123}I$, $^{125}I$ and $^{201}Tl$, etc. IAEA proposed a criteria for the clearance level of waste which depends on the individual ($10{\mu}Sv/y$) and collective dose (1 man-Sv/y), and concentration of each nuclide (IAEA Safety Series No 111-P-1.1, 1992 and IAEA RS-G-1.7, 2004). Radioactive wastes of $^{18}F$, $^{99m}Tc$, $^{123}I$, $^{125}I$ and $^{201}TI$ in the several types of container like Marinelli beaker, vial and plastic, were collected to measure the concentration of the waste of each nuclide in accordance with IAEA criteria. The measurement method and procedure of determining specific activity of the wastes using gamma emitters like MCA, gamma counter and beta emitters were developed. For the efficiency calibration of the detectors, CRM (certified reference material) which has the same dimension and shape was provided by Korea Research Institute of Standards and Science (KRISS). Correction factor of the radioactivity decay was calculated based on the measurement results, and the consideration of mutual relation with theoretical equation. The result of this study will be proposed as ISO standard.