• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.191-195
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• 1999

An integrated wastewater treatment pond system is developed for treatment and recycling of excreta from dairy cattle. It is composed of three ponds in series. A pit with a capacity of $10m^3$, 2-day hydraulic residence time, and overflow velocity of $1.5m^3m^{-2}day^{-1}$ is located internally in primary pond. It is designed for efficient sludge sedimentation and effective methane fermentation. It receives $5m^3/day$ of diluted cattle excreta by the water used for clearing stalls. A submerged gays collector for the recovery of methane is installed on the top of the pit. The average BOD_5 concentration of influent is 398.7mg/l. That of the effluent from primary pond is 49.2mg/l. About 88% of BOD_5 are removed in primary pond. It is assumed that about 60% of the influent BOD_5 is removed in the pit and that almost all of the carbon of the removed BOD_5 in the pit is converted to methane and carbon dioxide. Methane fermentation of the pit is well established at $16^{\circ}C$. This phenomena results from temperature stability, complete anaerobic condition, and neutral pH of the pit. Gas from the collector is almost 90% methane, less than 9% nitrogen, and less than 1% carbon dioxide. Thus a purified methane is produced, which can be used as energy source.

• Resources Recycling
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• v.15 no.3 s.71
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• pp.66-73
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• 2006

Continuous column adsorption experiments have been conducted fur artificial and actual wastewater which containing $Ni^{2+}$ by using manganese nodule as an adsorbent for the purpose of wastewater treatment along with an increased $Ni^{2+}$ recovery in the refining of manganese nodule. The adsorption features of $Ni^{2+}$ artificial wastewater were examined by taking the height of fixed bed, influent flow rate, and the initial concentration of adsorbate as the influential parameters. The adsorption capacity of manganese nodule and the rate constant for $Ni^{2+}$ adsorption were estimated employing Bohart-Adams equation. In addition, the variation of the adsorbed amount of adsorbate for each column according to the influent flow rate and the initial concentration of adsorbate was investigated based on the breakthrough curves fur each column. For serially connected columns, the adsorbed amount of $Ni^{2+}$ for each column was observed to increase gradually as the adsorption proceeded from the initial column to the final column. The variation of the breakthrough curve for actual wastewater with the height of fixed bed was not so significant as that for artificial wastewater, which was considered to be due to the high concentration of $Ni^{2+}$ in actual wastewater. Regarding the effect of the particle size of manganese nodule on adsorption, the adsorbed amount of adsorbate was found to somewhat increase as the particle size became smaller.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.2
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• pp.77-84
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• 2000

Aim to get operation factors, an In-vessel Composting of Wastewater Sludge was operated. The composting equipment is consisted of three chamber, 1st, 2nd and 3rd consequently. In the results, the temperature of fermentation had shown that 1st fermentation chamber(F/C) temperature was higher than that of 2nd and 3rd fermentation chamber. The temperature was steady in all steps during the sludge being composted, the ranges of each step were $50^{\circ}{\sim}59^{\circ}C$ of 1st F/C, $41^{\circ}{\sim}50^{\circ}C$ of 2nd F/C, and $32^{\circ}{\sim}37^{\circ}C$ of 3rd F/C. Organic material content of the end product was 28% and that of pH was 7.5. Properties of the compost which have been composted on optimized condition, were shown that is acceptable to use as a fertilizer. Even in the winter time, the composting system was working well without any trouble. According to result of investigation, the end-product of the system was satisfied with the standard for a fertilizer usage. HRT(hydraulic retention time) of entire process was appropriated to be 14 days(0.9 days at drying and 3.5, 4.4, 5.2 days at each step of fermentations, respectively).

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.3
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• pp.40-47
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• 2009

Coinjection of alcohol and air or alcohol flooding only were evaluated with 3-D soil tank for removal of nonaqueous phase liquid (NAPL) contaminant from soil. 70%-ethanol and 40%-isopropanol were used for non-NAPL-swelling alcohol and NAPL-swelling alcohol, respectively. 729 ml-benzene was placed in the 37 liter soil tank. Alcohols were respectively injected from the injection well placed near the bottom of the tank and mobilized free phase NAPL and aqueous phases were then recovered from the extraction well placed in the upper part of the soil tank. Approximately 50% of removed NAPLs were free-phase in all experiments. The results were completely different to the previous soil column experiment results and also implied that alcohol properties did not affect the NAPL removal efficiency in the 3-D soil tank experiment. Air was also co-injected with alcohol to evaluate co-injection effects on NAPL removal. Enhanced NAPL removal effect of co-injection of 70%-ethanol and air was also found even in the 3-D soil tank evaluation. However, co-injection effect of 40%-iso-propanol and air was less apparent. This study determined that the most important parameter governing alcohol flooding for NAPL removal would be extraction capacity to recover NAPL and aqueous phase flowing in the soil. More researches are required for improving recovery efficiency of extraction well in real soil contamination conditions.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.2
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• pp.15-29
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• 2016

This study investigated the environmental and economical assessment for sewage sludge treatment options including biogasification, incineration, carbonization, drying, and solidification. Considering B/C ratio for an anaerobic digestion treatment, for $270,000m^3/d$ (over $1,150m^3/day$), B/C was 1, as the moisture content increased to 95 %, B/C was 1 for $100000m^3/d$ (capacity of $400m^3/day$). Anaerobic digestion+solidification was the most economically feasible, then Anaerobic digestion+incineration and anaerobic digestion+drying were the next economically feasible and then anaerobic digestion+carbonization was the least economically feasible. If anaerobic digestion efficiency was improved to 45%, the treatment costs for anaerobic digestion+carbonization, anaerobic digestion+incineration and anaerobic digestion+drying were decreased to 3,000~5,000 won/t and the costs for anaerobic digestion+solidification was decreased to 2,000~3,000 won/t due to increasing of the beneficial cost of the biogas production.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.39-48
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• 2016

An information management system for a solid waste landfill site was developed, in this study, to optimize the operation and management of solid waste landfill in real time in addition to provide the information of landfill status to the landfill operator, public official concerned and local residents. The landfill information management system is composed of two systems (Solid waste landfill history management system and landfill operation and performance management system). The solid waste landfill history management system based on automated RFID/LPR system allows landfill operators to provide information of waste collection vehicles and received waste. In addition, the system aids in the identification of 3-dimensional (3D) position for landfilled solid wastes. Using the landfill operation and performance management system based on 3D laser scanner delivers information about landfill volume, settlement, landfill density, and current landfill capacity to landfill operators in real time, resulting in optimum space utilization. Ultimately, this system would dramatically reduce exposure of landfill operators to hazardous materials and improve the productivity of landfill operations.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.51-62
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• 2005

The effects of the processing mixture of food wastes and various organic wastes when vermicomposted on earthworm(Eisenia foefida) growth, the cast production amounts and the chemical properties of casts were evaluated. The substrates used in this experiments were cow manure, pig manure sludge, fermented pig manure with sawdust, nightsoil sludge, and sewage sludge and were respectively mixed with food wastes at a ratios of 50:50(v/v). The control consisted of food wastes alone without other wastes. All of earthworm died in the food wastes 100%, therefore the process of food wastes alone by vermicomposting was impossible in this experiment. Worm cast produced sufficiently contained quantities of available phosphorus, exchangeable potassium, exchangeable magnesium, and cation exchange capacity. The increase of earthworm's biomass occured on the mixtures of food wastes and cow manure, fermented pig manure with sawdust. Dry weight of worm cast was the highest on the mixtures of food wastes and fermented pig manure with sawdust and the proportion of cast weight after vermicomposting was significantly the highest on the mixtures of food wastes and cow manure($p{\leq}0.05$). Also, the mixtures of food wastes and cow manure, and fermented pig manure with sawdust showed a positive values of conversion rate and conversion efficiency rate of organic matter to earthworm tissue than that of other treatments. These results suggested that cow manure and fermented pig manure with sawdust are adequate to process with food wastes by vermicomposting.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.1
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• pp.73-82
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• 2020

This study was conducted to investigate the differences in carbon storage capacity of soil between the conventional and the organic agricultural cultivation followed by the assessment of their economic values. An analysis of 107 samples in the organic and the conventional rice cultivation soils in six regions across South Korea showed that the five regions, Buyeo-II, Gimhae, Sancheong-I, II and Suncheon, had higher organic soil carbon contents than those of values observed on the conventional soils with the exception of the Buyeo-I areas. Based on the results from soil carbon contents, the carbon storage were estimated to be 36.1 megagram carbon (MgC) per ha in the organic paddy soils, while its conventional paddy soils were 29.4 MgC per ha. It showed that the organic paddy soils were 23 % greater than that of its conventional paddy soils. It was estimated that the carbon trading price for economic assessment was ￦758,100 per ha in the organic paddy soil and ￦617,400 per ha in the conventional paddy soil.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.2
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• pp.71-76
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• 2001

Recently, sludge disposal becomes one of the most serious environmental problems. Because the landfilling and ocean dumping of sludge materials will be prohibited in the near future, the proper treatment?disposal methods should be investigated. Also, oyster shells, piled at the coast, cause adverse effects in coastal fishery, public water surface, natural landscape, public health and so on. Thus, the purpose of this study is to evaluate the dissolution characteristic of metal compounds during soil application experiment using sewage treatment sludge mixed with oyster shells. The dissolution experiment conducted 100days under artificial rainfall and farming soil, mixed with sewage treatment sludge and oyster shells, was put into the pots(approx. 0.5L). The results from dissolution experiment as follows. 1. K, Na was $5{\sim}20mg/{\ell}$, and Ca was less than $90mg/{\ell}$. 2. Heavy metals such as Cd, Cu, As, Pb, Cr, Hg are dissoluted far less than the soil pollution guideline. The application of sewage sludge mixed with oyster shells increases pH(soil acidity)and buffer capacity(CEC) of farming soil, and heavy metals are thought to be attached to soil as insoluble forms.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.2
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• pp.101-107
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• 2001

The experiment was conducted to investigate the agricultural utility of macro-porous calcium-silicate rnineral(CellCaSi) as topsoil mixture, as well as to estimate as a soil conditioner. The bulk density of CellCaSi which is consisted of various particle sizes ranging from 1mm to 3.35mm was about $0.42g/cm^3$, and its maximum porosity was approximately 81.4%. We also investigate gerrnination rates for Cabbage and Lettuce to obtain the suitable mixing ratios of CellCaSi with topsoil. Among 4 different mixing ratios, the germination rates of ropsoil mixed with 10% of CellCaSi were 94.1% and 64.6% for Cabbage and Lettuce, respectively resulted in the mosr suitable for germination. The growth rates for Cabbage and Lettuce showed thar 10% and 20% of CellCaSi treatments signification influenced the fresh weight. To observe the adsorption capacity of CellCaSi, CellCaSi was treated with a chemical fertlizer(N:P:K=18:18:18). lncreasing the contents of N, P and K, the amounts of adsorption by CellCaSi for these element also increased. The most suitable types nutrient resources for growth condition of Cabbage, and Lettuce were Fer-1 and Fer-0.5.