• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.3 s.116
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• pp.72-78
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• 2006

The extraction properties of the biological waste originated from the Tobacco industry were evaluated. The biological waste have been recycled and transformed into a valuable material, so called a reconstituted tobacco sheet(Recon) by the papermaking process. In this process, The mechanical extraction process, which divides the mixed raw material slurry into the soluble stock and the insoluble stock, could affect not only the quality of final Recon product but also the productivity of whole Recon making process. This study investigated the effects of the extraction process on the slurry properties in detail. In order to quantify the amounts of the solubles which resided in the insoluble fibers, the washing treatment of the stock before and after squeezing process was applied. The amounts of the residual solubles showed little changes according to each stage of the extraction process. The fractionation of the slurry showed the difference in the amount of soluble in the stock depending on the size of the biological waste. After the extraction process, the bigger size fiber portion contained about 19%(by weight) in soluble after pressing but the smaller size fiber portion 9% in soluble. The fractionation ratio of the stocks also was changed by the screw press process, which could demonstrate the physical effects of the mechanical extraction.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.1
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• pp.57-68
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• 2023

In this study, coffee waste was recycled into nitrogen-doped porous carbon fibers as an active material for high-energy EDLC (Electric Double Layer Capacitors). The coffee waste was mixed with polyvinylpyrrolidone and dissolved into dimethylformamide. The mixture was then electrospun to fabricate coffee waste-derived nanofibers (Bare-CWNF), and carbonization process was followed under a nitrogen atmosphere at 900℃. Similar to Bare-CWNF, the as-synthesized carbonized coffee waste-derived nanofibers (Carbonized-CWNF) maintained its fibrous form while preserving the composition of nitrogen. The electrochemical performance was analyzed for carbonized coffee waste (Carbonized-CW)-, carbonized PAN-derived nanofibers (Carbonized-PNF)-, and Carbonized-CWNF-based electrodes in the operating voltage window of -1.0-0.0V, Among the electrodes, Carbonized-CWNF-based electrodes exhibited the highest specific capacitance of 123.8F g^-1 at 1A g^-1 owing to presence of nitrogen and porous structure. As a result, nitrogen-contained porous carbon fibers synthesized from coffee waste showed excellent electrochemical performance as electrodes for high-energy EDLC. The experimental designed in this study successfully demonstrated the recycling of the coffee waste, one of the plant-based biomass that causes the environmental pollution into high-energy materials, also, attaining the ecofriendliness.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.533-539
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• 2014

Mine wastes such as acid mine drainage (AMD) can cause the detrimental effects on surrounding environment, thereby eventually threatening human health. Main objective of this study was to evaluate the neutralizing effect of fly ash (FA) as a stabilizing material AMD. Field plot was constructed in a coal waste depot which has caused aluminium-whitening adjacent to the stream. Different mixing ratios of FA were applied on a top of the soil, and then the physicochemical properties of runoff and soil were monitored. Constructed plots were as following: control (mine waste only (W)), mine waste + 20% ($w\;w^{-1}$)of FA (WC20M), mine waste + 40% ($w\;w^{-1}$)of FA (WC40M), and WC40M dressed with a fresh soil at the top (WC40MD). Result showed that initial pH of runoff in control was 5.09 while that in WC40M (7.81) was significantly increased. For a plot treated with WC40M, the concentration of Al in runoff was decreased to $0.22mg\;L^{-1}$ compared to the W as the control ($4.85mg\;L^{-1}$). Moreover, the concentration of Fe was also decreased to less than half at the WC40M compared to the control. Application of FA can be useful for neutralizing AMD and possibly minimizing adverse effect of AMD in mining area.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.4
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• pp.355-367
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• 2017

The decommissioning of Kori unit 1, which was permanently shut down in June of 2017, will be the first instance of the dismantling of a commercial nuclear power plant in Korea. The disposal of waste during the dismantling process accounts for a large part of the total decommissioning cost. Therefore, structures consisting of activated and contaminated concrete must be economically and safely dismantled by establishing a proper dismantling strategy. This study focuses on optimized dismantling and disposal scenarios pertaining to a biological shield. Several dismantling cases, regulations and technologies related to waste treatment as these practices pertain to nuclear power plants are analyzed. To minimize the amount of waste from the biological shield dismantling process, an optimized dismantling scenario is presented and disposal alternatives for dismantled concrete waste are proposed.

• Journal of Korean Society on Water Environment
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• v.28 no.5
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• pp.663-668
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• 2012

The feasibility of enhancing biological nutrient removal from an industrial wastewater was tested with food waste leachate and sugar liquid waste as external carbon sources. Long term influences of adding external carbon sources were investigated to see how the biological nutrient removal process worked in terms of the removal efficiency. The addition of the external carbons led to a significant improvement in the removal efficiency of nutrients: from 49% to approximately 76% for nitrogen and from 64% to around 80% for phosphorus. Approximately, 20% of the removal nitrogen was synthesized into biomass, while the remaining 80% was denitrified. Though the addition of external carbon sources improved nutrient removal, it also increased the waste sludge production substantially. The optimal observed BOD/TN ratio, based on nitrogen removal and sludge production, was around 4.0 in this study.

• Journal of Mushroom
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• v.14 no.4
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• pp.237-243
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• 2016

Spent mushroom substrate (SMS) has generally been used for the manufacture of animal feed and production of bio fuel. Limited research has been conducted in the utilization of SMS as a co-material for composting. Therefore, the main purpose of this study was to evaluate the feasibility of composting vegetable waste mixed with various ratios of SMS (30, 40, and 50%). The results showed that the C/N ratio decreased when both sawdust (from 22.0~28.8 to 17.7~20.4) and SMS (from 18.5~19.5 to 12.7~16.8) were applied for composing, owing to increased contents of nitrogen. A maturity test conducted using mechanical (Solvita) and germination tests revealed that both sawdust (92.0~101.9%) and SMS (87.8~89.2%) satisfied a criteria of maturity standard (70%). A correlation analysis between compost maturity and its chemical properties revealed that the C/N ratio and pH were the most dominant parameters for compost maturity. Overall, SMS could be utilized as a compost material and especially, vegetable waste mixed with SMS could provide sufficient nutrients for crop growth.

• 한국환경농학회:학술대회논문집
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• 2011.07a
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• pp.289-289
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• 2011

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.332-337
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• 2019

BACKGROUND: From year 2005, landfill for food waste has been prohibited. Also, according to London agreement in year 2013, ocean discharge for livestock manure, sewage sludge, and food waste has been regulated. Alternative way for food waste disposal is incineration. However, due to high moisture content, additional input for energy is needed. Therefore, effective way for food waste disposal such as application of food waste compost is needed. METHODS AND RESULTS: Seven different treatments (livestock compost, food waste compost, food waste + livestock compost, livestock compost + chemical fertilizer, food waste compost + chemical fertilizer, food waste + livestock compost + chemical fertilizer and control) were applied to tomato crop. All treatments were replicated with completely randomized design. Tomato growth treated with LC+NPK showed the highest values at 6 weeks for all parameters such as leaf length (11.80 cm), leaf width (6.88 cm), and chlorophyll (61.12 O.D.), compared to other treatments. Subsequently the FWC+LC+NPK treatment was followed (11.51 cm, 6.40 cm, 59.50 O.D. for leaf length, leaf width, and chlorophyll, respectably). EC, OM contents, and CEC in the soil treated with the composts significantly increased. CONCLUSION: To evaluate the effect of food waste compost application on tomato growth and soil chemical properties, we carried out field experiment treated with 7 treatments with 3 replicates. The LC+NPK treatment showed highest values for all parameters. Some parameters such as shoot length and total length for tomato were not significantly different between the LC+NPK and the FWC+LC+NPK treatments.

• Journal of Microbiology and Biotechnology
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• v.21 no.5
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• pp.494-502
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• 2011

Coenzyme $Q_{10}$ ($CoQ_{10}$) is a widely used supplement in heart diseases treatment or antioxidative dietary. The microbial production of $CoQ_{10}$ was enhanced by addition of solanesol and novel precursors recovered from waste tobacco. The novel precursors were separated by silica gel and identified as ${\alpha}$-linolenic acid (LNA) and butylated hydroxytoluene (BHT) based on the effect on $CoQ_{10}$ production and GC-MS. The effects of novel precursors on $CoQ_{10}$ production by Sphingomonas sp. ZUTE03 were further evaluated in a two-phase conversion system. The precursor's combination of solanesol (70 mg/l) with BHT (30 mg/l) showed the best effect on the improvement of $CoQ_{10}$ yield. A maximal $CoQ_{10}$ productivity (9.5 mg $l^{-1}$ $h^{-1}$) was achieved after 8 h conversion, with a molar conversion rate of 92.6% and 92.4% on BHT and solanesol, respectively. The novel precursors, BHT and LNA in crude extracts from waste tobacco leaves, might become potential candidates for application in the industrial production of $CoQ_{10}$ by microbes.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.268-274
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• 2002

Enzymatic hydrolysis of waste office paper was evaluated using three commercial cellulases, Acremonium cellulase, Meicelase, and Cellulosin T2. Varying the enzyme loading from 1 to 10% (w/w) conversion of waste office paper to reducing sugar was investigated. The conversion increased with the increase in the enzyme loading: in the case of enzyme loading of 10% (w/w), Acremonium cellulase yielded 79%conversion of waste office paper, which was 17% higher compared to Meicelase, 13% higher than that of Cellulosin T2. Empirical model for the conversion (%) of waste office paper to re-ducing sugar (x) was derived from experimental results as follow, x = $kE^{m}t^{(aE+b)}$ where k, m, a, and b de-note empirical constants. E indicates initial enzyme concentration.