• Journal of Korean Society of Water and Wastewater
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• v.26 no.5
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• pp.629-636
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• 2012

This study focuses on the feasibility of bio-gas production using anaerobic digestion by measuring methane generation and biodegradability through the BMP test of industrial organic wastes. Organic wastes consist of entrails of pigs and organic residues of rumen generated from slaughter houses, wastewater sludge from slaughter waste water, fish offal and residues of vegetables from public wholesale markets, and wastewater sludge from the process of wastewater treatment in paper mill. The cumulative methane production by BMP test ranges from 149.3 ml/g-VS to 406.6 ml/g-VS and this is similar to methane generation of the normal wastewater sludge and food waste. As a result of measurement of biodegradability, wastewater sludge (S1 ~ S4) is low, ranging from 27.1% to 58.9 % and organic residues of rumen (G1) is low at 49.6 %. In conclusion, it turned out that raising the hydrolysis by various pre-treatments is necessary in order to produce bio-gas by using industrial organic wastes.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.163-163
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• 2019

The rapidly growing global population increases the awareness of water, energy, and food security worldwide. The concept of Water, Energy, and Food nexus (hereafter, WEF nexus) has been widely introduced as a new resources management concept that integrate the water, energy, and food in a single management framework. Recently, WEF nexus analyzes not only the interconnections among the resources, but also considers the external factors (such as environment, climate change, policy, finance, etc) to enhance the resources sustainability by proper understanding of their relations. A nation-level resources management is quite complex task since multiple regions (e.g., watersheds, cities, and counties) with different characteristics are spatially interconnected and transfer the resources each other. This study proposes a multiple region WEF nexus simulation and transfer model. The model is equipped with three simulation modules, such as local nexus simulation module, regional resources transfer module, and optimal investment planning module. The model intends to determine an optimal capital investment plan (CIP), such as build-up of power plants, water/waste water treatment plants, farmland development and to determine W-E-F import/export decisions among areas. The objective is to maximize overall resources sustainability while minimize financial cost. For demonstration, the proposed model is applied to a semi-hypothetical study area with three different characterized cities. It is expected the model can be used as a decision support tool for a long-term resources management planning process.

• Journal of Korean Society on Water Environment
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• v.38 no.2
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• pp.95-102
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• 2022

Studies for improving the efficiency of the traditional anaerobic digestion process are being actively conducted. To improve anaerobic digestion efficiency, this study tried to derive the optimal pretreatment conditions and mixing conditions by integrating the heat solubilization pretreatment of sewage sludge, livestock manure, and food waste. The soluble chemical oxygen demand (SCOD) increase rate of sewage sludge before and after heat solubilization pretreatment showed an increased rate of 224.7% compared to the control group at 170℃ and 25 min and showed the most stable increase rate. As a result of the biomethane potential test of sewage sludge before and after heat solubilization pretreatment, the total chemical oxygen demand (TCOD) and SCOD removal rates increased as the heat solubilization temperature increased, but did not increase further at temperatures above 170℃. In the case of methane generation, there was no significant change in the cumulative methane generation from 0.134 to 0.203 Sm³-CH₄/kg-COD at 170℃ for 15 min. As a result of the integrated digestion of organic waste, the experimental condition in which 25% of the sewage sludge, 50% of the food waste, and 25% of the livestock manure were mixed showed the highest methane production of 0.3015 m³-CH₄/kg-COD, confirming that it was the optimal mixing ratio condition. In addition, under experimental conditions mixed with all three substrates, M4 conditions mixed with 25% sewage sludge, 50% food waste, and 25% livestock manure showed the highest methane generation at 0.2692 Sm³-CH₄/kg-COD.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.2
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• pp.109-124
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• 1990

A rapid processing method for fish sauce of high quality stability and favorable flavor was investigated using mackerel waste as starting material. The chopped waste was homogenized with water and hydrolyzed by commercial proteolytic enzymes such as Complex enzyme-2000($2.18\cdot10^4$ U/g solid, Pacific Chem. Co.) and Alcalase ($1.94\cdot10^4$ U/g solid, Novo) in a cylindrical vessel with 4 baffles and 6-bladed turbine impeller. Optimal pH and temperature for the hydrolysis with Complex enzyme-2000 were 8.0 and $50^{\circ}C$, and those with Alcalase were 9.0 and $55^{\circ}C$. In both cases, the reasonabe amount of added water and enzyme concentration based on the waste weight were $40\%,\;3\%$ and hydrolyzing time was 100 min. Thermal treatment of the hydrolysate with $6\%$ of invert sugar for 2 hours at $90^{\circ}C$ was adequated to inactivation of the enzymes and pasteurization of the hydrolysate. Flavor, taste and color of the hydrolysate were improved during the thermal treatment in which the browning reaction products might participate and result in antioxidative and bactericidal effects. Combined use of $0.005\%$ of Caryophylli flos with $6\%$ of invert sugar was also effective for the improvement of taste. Yield of the fish sauce based on the total nitrogen of the raw waste was $93.7\~94.9\%$, and $87.6\~87.9\%$ of the total nitrogen in the fish sauce was in the from of amino nitrogen. The pH, salinity and histamine content of the fish sauce prepared with $15\%$ of table salt were $6.1\~6.2$, $14.0\~14.5\%$ and less than $10mg\%$, respectively. The fish sauce was stable on bacterial growth during the storage of 60 days at $26\pm3^{\circ}C$ and the quality was also maintained.

• Journal of Korean Society on Water Environment
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• v.23 no.5
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• pp.781-788
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• 2007

The Carbon source to enhance the denitrification is essential matter in the advanced sewage treatment. For the high level of nutrient removal, external carbons such as ethanol, methanol, volatile fatty acids and so on should be needed. In this study, the methods to increase the sludge solubilization and acidification rate were compared with waste activated sludges and food waste leachate. Ultrasonication and acids were used for the pretreatment of organic particles in sludges. As a results, the optimal temperature and HRT were $60^{\circ}C$ and 5 days, respectively. HAc, HPr, HBr, and other VFAs for acid fermentations reduced up to 22, 16, 14, and 48% with HRT reduction. For the increase of solubilization, 28% of solids destruction rate was shown at 0.3 watts/mL.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.1
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• pp.23-33
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• 2017

In this study, water and organic treatment efficiency and operating characteristics (temperature, salinity effect) were evaluated when food waste with high water content was treated by Bio-dying method. In addition, the optimum conditions for producing pellets for evaluating the decomposition products as SRF(Solid Refuse Fuel) after Bio-drying and evaluating the use value of SRF as a solid fuel were analyzed. As a result, the temperature, $CO_2$ concentration, organic matter removal rate and weight reduction rate according to the daily dose were about 86% and 68% at the input of 2.4 kg/day. The optimal food waste input was estimated to be 2.4 kg/day. As a result of the pellet molding and produce, Pellets can be produced within 10~25% of raw material water content. It was judged that the water content of 25%, which showed the best quality results in terms of external shape maintenance and strength. The high calorific value of SRF of decomposition products after Bio-drying was more than 3,500 kcal/kg.

• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.332-338
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• 2000

This experiment was conducted to investigate the effects of feeding with MS (miraculous soil-bacteria)-fermented food waste on feeding efficiency and meat quality of mallard. Twenty one heads of 12 weeks-old mallards were fed with three different mixing rates of MS-fermented food waste (0, 20 and 50 %) with 7 replicates. After 6 weeks of feeding, weight gain and feed intake were measured to estimate feeding efficiency, moreover physico-chemical characteristics, amino acids and fatty acids of the fresh slaughtered mallards were analyzed to determine meat quality. The feeding efficiency of 0 % fermented food waste (control) was significantly (p<0.05) higher than other treatments. Water holding capacity and pH were not significantly differed. The color value in lightness of control meat was higher, while in redness was lower than that of the plots mixed with fermented food waste. Total content of amino acids in thigh meat was relatively lower in control, but that in breast meat showed a reverse trend. The amount of unsaturated fatty acids in both thigh and breast meat was the highest in the 50 % mixed plot. Considering economic and environmental aspects for mallard feeding, this results indicated that MS fermented food waste could be a useful resources for mallard feed.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.2
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• pp.110-120
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• 2004

This research sought to analyze the food waste collection and transportation system in Korea's related public resource-making facilities, address related problems, and suggest a reasonable alternative measure. For the food waste sorting-out and discharging methods, apartments and similar housings use containers, and individual-style housings use 'quantity-proportional' bags. The sorting and discharging methods should be improved to boost the reuse of resource-made output. The analysis of collection and transportation costs by local governments indicates that they range from 30,000 won to 150,000 won per ton, varying greatly by characteristics of local governments, thus suggesting a need to establish costs calculation criteria to justify the costs. Charges imposed to each household were not greatly problematic in the case of quantity-proportional bags; however, in the case of apartments and similar housings, charges varied greatly, suggesting a need to impose differentiated charges calculated on the basis of collection and transportation costs according to regions. Many places used household-garbage collection vehicles to collect food waste, raising the possibility of causing complaints on leaching water and bad odors. Thus, exclusive food waste collection vehicles should be gradually introduced. Also, in certain places, vehicles should travel more than 20km to collect food waste, and in such cases, a cargo transferring system should be introduced to boost efficiency in carriage.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.4
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• pp.111-120
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• 2000

Chestnut processing plants have wasted large amounts of chestnut inner skin waste, which contains chestnut flesh. To review the availability of the chestnut flesh as a food ingredient, We have analyzed the physiochemical characteristics of the chestnut powder extracted from inner skin waste. Then, we have examined on tastes and other sensory tests using breads, noodles and jellies made from various percents of chestnut powder. The results are as follows; The water absorbing capability and amylose degradability of the powder from the inner skin waste are 40% and 8% higher than those of the core chestnut powder, respectively. Also, the power from the inner skin waste shows similar characteristics with one of the core chestnut in iodine reaction. The breads, noodles and jellies from the chestnut powder have similar characteristics in flavor, hardness, elasticity, cohesiveness, adhesiveness, chewing property, and gumminess with the traditional ones.

• Journal of Urban Science
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• v.8 no.2
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• pp.35-39
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• 2019

With the rapid progress of society and economic growth, more and more factories are put into construction, although to a certain extent to promote the development of our country's economy, but the waste gas and waste water produce also harm the environment.Among them, air pollution causes great damage to the environment and harms human health.In order to protect people's safety and health, people began to look for some measures to control air pollution, one of the most effective way is to plant more green plants, using plants for air purification.