• Journal of Environmental Health Sciences
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• v.18 no.1
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• pp.63-68
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• 1992

This study was performed to investigate the seasonal variation of the composition of domestic solid wastes and the characteristics of the leachate sampled in In-Cheon sanitary landfill site. The results were as follows 1. Combustible part was larger than incombustible part of the domestic solid wastes in spring and sumer. 2. The food waste was major source of solid wastes in In-Cheon city as 36.5%, and its variation by seasons was negligible. 3. BOD of the leachate was in the range of 853~7, 350mg/l, and fluctuated by seasons. 4. The mean of COD$_{cr}$ Was 5, 044mg/l, the mean of COD$_{Mn}$ was 2, 212mg/l. Namely, the method by $K_{2}Cr_{2}O_{7}$ was more sensitive than the method by KMnO$_{4}$. 5. TOC was in the range of 773~3, 958mg/l, it was lower than BOD.

• Journal of the Korean Geotechnical Society
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• v.36 no.5
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• pp.17-24
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• 2020

In order to analyze the effect of applying the bioreactor landfills on the waste landfill for acceleration of waste biocompression, a settlement experiment was performed. The secondary compression indices (C_α) were analyzed, and compared with the results of experimental studies conducted in other countries. Analyses of C_α from the experiment showed that the recirculation method of mixing leachate and FWL could accelerate the waste settlement as much as 2.9 times and 2 times more than the leachate recirculation and the sanitary landfills due to additional biocompression generated by the organic matter in FWL. The C_α in this study was smaller than the C_α of the other studies due to the low organic content of the waste in accordance with domestic waste policies to reduce food waste. The relation between biodegradable waste content and C_α was analyzed. The C_α of the waste was shown to be sensitive to biodegradable waste content, and become higher as the content of the biodegradable waste increases.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.1
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• pp.39-45
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• 2008

As a waste management tool, the prohibition of landfilling of food waste has enforced since 2005. the composition of municipal solid waste (MSW) has changed dramatically. In this study, MSW generated from a small city collected once a year in 2004, 2005 and 2007, to qualify the characteristics of MSW before and after implementation of the tool. The prohibition of landfilling of food waste dramatically reduces food waste in MSW to 5.5 weight %, and on the other hand results to increase papers to 50.6 % and plastics to 22.6 %, The bulk density lowers to 50 %, which newly propose the necessity of volume reduction and incineration of MSW to ensure efficient transport and disposal. As water content of MSW reduces to 15.9 %, lower heat value of MSW after prohibition of landfilling of food waste increase to 3565.6 kcal/kg. Mitigation of bad smell and waste leachate with lower contaminants are recommendable as a kind of positive effects benefited by the tool.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.110-110
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• 2022

According to the statistics of the Ministry of Environment, the amount of food waste generated in Korea is 15,903 tons, which accounts for about 30% of the daily household waste. Food waste in Korea is on the rise, and various odors, greenhouse gases, and leachate generated in the process of discharging, transporting, and processing are emerging as social problems. Accordingly, there is a need for a method for recycling food waste. Therefore, this study was carried out to establish an appropriate limiting dose by manufacturing fertilizer mixed with food waste powder and treating it on tomatoes to investigate the growth and yield of crops. The experiment was carried out with continuous cultivation in 2021 (1st year) and 2022 (2nd year), and the treatment groups were set to No Treatment (NT), Chemical Fertilizer (CF), Mixed Fertilizer (MF), and Mixed Fertilizer×2 (MF×2). As a result of the 1st year growth survey, shoot and root length did not show a significant difference between the treatment groups, and the fresh weight showed a significant difference between the MF and MF×2. As a result of the 2nd year growth survey, there was no significant difference in shoot length, root length, and dry weight between the treatment groups, and the fresh weight of the CF was significantly greater than that of the MF×2. The yield of 1st year, MF×2 increased significantly compared to other treatment groups. In the case of 2nd year, CF, and MF×2 show significantly high values compared to NT. Judging from these results, continuous cultivation using food waste powder mixed fertilizer did not have a significant effect on crop growth and yield. However, it is considered that several studies including continuous cultivation experiments are needed to accurately set the appropriate application amount and limit the application amount of the mixed fertilizer for food waste.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.203-208
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• 2011

Dumping of wastes at sea will be strongly prohibited from 2012 by London Dumping Convention. So, finding the method for treatment of food waste at ground is needed urgently. The solution for above mentioned problem is the resource development from food waste leachate by using Upflow Anaerobic Sludge Blanket (UASB) process. In this research, we try to find out the effect of effluent recirculation and internal return influence on organic removal efficiency and biogas production. Laboratory investigation was conducted for 25 days with only internal recycling, and then, effluent recirculation was performed. As the result of experiments, the organic removal efficiency was above 90%, and the content of methane was 78~80% during operating time. Also, when UASB reactor was operated to over the 3 Q effluent recirculation, there was not 1 N-NaOH consumption any more, therethrough the experiment was economically and stably carried out.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.3
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• pp.397-402
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• 2006

The treatment characteristics of leachate produced from pretreatment facilities like composting and feeding were investigated in a mesophilic anaerobic treatment. Experiments were performed in two phase which were acidification and methane fermentation. The acidification step was optimized for OLR from 1 to $4.5kg\;COD/kg\;VS{\cdot}day$ without adding NaOH. As experiment dates became longer, the solubilization ratio of particles increased up to 30% over 70 days. TVA was generated up to maximum 9,970mg HAc/L at OLR of $2kg\;COD/kg\;VS{\cdot}day$. But TVA was generated to minimum 6,519mg HAc/L at OLR of $4.5kg\;COD/kg\;VS{\cdot}day$. The acidification ratio was analyzed from 10.9% to 3.8% at OLR of $2kg\;COD/kg\;VS{\cdot}day$ and $4.5kg\;COD/kg\;VS{\cdot}day$ respectively. After 55 days, salt contents in the acid fermenter were accumulated and stabilized at the concentration of 3,150mg/L. Sodium ion($Na^+$) concentration was stabilized at 1,300mg/L. At methane fermentation step, biogas was generated up to 750ml and 937.5ml at the feeding volume of 20ml and 25ml respectively for acid fermented liquid during 25 days. About 80% of total biogas was generated during early 15 days and 95% were generated during 18 days respectively. After 25 days of the BMP test, acetic acid was removed approximately 97% and 98%, in case of those two experimental conditions.

• Solar Energy
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• v.18 no.3
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• pp.197-203
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• 1998

A 5 ton/day pilot scale two-phase anaerobic digester was constructed and tasted to treat Korean food wastes in Anyang city. The process was developed based on 3 years of lab-scale experimental results on am optimim treatment method for the recovery of biogas and humus. Problems related to food waste are ever Increasing quantity among municipal solid wastes(MSW) and high moisture and salt contents. Thus our food waste produces large amounts of leachate and bed odor in landfill sites which are being exhausted. The easily degradable presorted food waste was efficiently treated in the two-phase anaerobic digestion process. The waste contained in plastic bags was shredded and then screened for the removal of inert material such as fabrics and plastics, and subsequently put into the two-stage reactors. Heavy and light inerts such as bones, shells, spoons and plastic pieces were again removed by gravity differences. The residual organic component was effectively hydrolyzed and acidified in the first reactor with 5 days space time at pH of about 6.5. The second, methanization reactor part of which is filled with anaerobic fillters, converted the acids into methane with pH between 7.4 to 7.8. The space time for the second reactor was 15 days. The effluent from the second reactor was recycled to the first reactor to provide alkalinities. The process showed stable steady state operation with the maximum organic rate of 7.9 $kgVS/m^3day$ and the volatile solid reduction efficiency of about 70%. The total of 3.6 tons presorted MSW containing 2.9 tons of food organic was treated to produce about $230m^3$ of biogas with 70% of methane and 80kg humus. This process is extended to full scale treating 15 tons of food waste a day in Euiwang city and the produced biogas is utilized for the heating/cooling of adjacent buildings.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.2
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• pp.59-66
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• 2016

The purpose of this study was to review of technical, economical feasibilities regarding Integrated Two-Phase Anaerobic Digestion(ITPAD) method. In order for that, operation conditions and data with 24tpd capacity of operating ITPAD plant were analyzed. The result showed that VS removal efficiency was 73.7% and total amount of biogas was generated $1,239m^3/day$ on the average that represents $54.4m^3/ton$-input of generation efficiency. ITPAD had advantages in terms of required area and energy for heating which were analyzed 15.9%~47%, 11.6%~17.8% lower respectively compared to Conventional Separated Two-Phase Anaerobic Digestion(CSTPAD) method. Thus, it is considered the ITPAD has comparatively high feasibility to be expanded and commercialized to dispose high concentration organic matter of waste such as food waste and its leachate.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.1
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• pp.19-29
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• 1994

The purpose of this study was to investigate the feasibility of composting of vegetable wastes containing high moisture. The parameters investigated were the effect of energy source addition, difference in bulking agent and recirculation of leachate produced during composting. Laboratory scale composting reactors were used in this study. Chinese cabbages were used as a vegetable waste. Dog food was added to the vegetable waste as a energy source. Wood chips and leaves of platan were used as bulking agents. There may be an appropriate amount of energy source to be added for composting high moisture content vegetable waste. In this study, the appropriate amount of energy source was 20% of the vegetable waste by weight basis. Recirculation of total amount of leachate produced each day on the same day may not be an appropriate approach due to the significant heat-quenching effect. When the total amount of leachate produced was equally devided and recirculated everyday through the whole composting period, the heat-quenching effect was comparatively less significant. There were no notable differences in the temperature profile and the $CO_2$ evoluation rate when leaves were used instead of wood chips as bulking agents. Considering waste recycling, it is desirable to use leaf waste as bulking agents if available, because the leaves are also wastes to be disposed of.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.4
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• pp.78-85
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• 2000

Leachate from acidogenic fermentation of food waste was effectively treated by the UASB reactor at $37^{\circ}C$. The efficiency of COD removal was consistently over 96% up to the loading rates of $15.8g\;COD/{\ell}{\cdot}d$. The methane production rate increased to $5.5{\ell}/{\ell}{\cdot}d$. Of all the COD removed, 92% was converted to methane and the rest presumably to biomass. At loading rates over $18.7g\;COD/{\ell}{\cdot}d$, the efficiency of COD removal decreased due to the sludge flotation and washout in the reactor, which resulted from short HRT of less than 10.6 hr. The SMA(specific methanogenic activity) analysis showed that the VFA-degrading activity of granule was the highest for butyrate, and the lowest for propionate. This result was consistent with the observation that the residual propionate concentration was the highest among the VFAs in the effluent. Typical granules were found to be mainly composed of microcolonies of Methanosaeta. Though the original seed sludge contained 64.3% of particles smaller than 1.4mm, the sludge particles had been growing during the fermentation, and at the final step of this study, 75.1% of the particles were found to be larger than 1.4 mm in the UASB reactor.