• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.60-66
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• 2003

The purpose of this study was to investigate the effective pretreatment of foodwaste for the anaerobic digestion. Considering the foodwaste generation and the anaerobic digester for municipal wastewater sludges, the some pretreatment processes were performed such as the grinding of foodwastes with the addition of water, the mixing with sludges, and the hydrolysis with the addition of NaOH. The results were as followings ; 1. As the stage of feasibility test in laboratory scale, the foodwaste grinding using a household garbage disposer was performed with three different water mixing ratios of 1:1, 1:5 and 1:9 as weight base. The physicochemical characteristics of grinded foodwaste were analyzed and the effective conditions was recommended as the 1 :5mixing ratio of foodwaste and water and the below 8mm particle size. 2. And the mixing of foodwaste and municipal wastewater sludge was studied with three different mixing ratios of 1:9, 3:7 and 5:5 as weight base. The physicochemical characteristics of the mixed foodwaste and sludges were analyzed and the effective mixing ratio was recommended as 3:7 of foodwaste and sludge.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.1
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• pp.53-61
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• 1997

This study was conducted to analysis citizen's attitude and style to the foodwaste from l0th Sept. to 30th Sept. in 1996. The research was used questionare method and analysis was used prequency analysis and cross table method by SPSS (scientific statistics). The foodwaste of householdwaste account for 24.8%, and the magnitude by the kinds of garbage were waste from pre-cocking stage, fruitshell, foodwaste remained after eating, septic foodwaste during storage. The more the housewives'age are young, foodwaste volumne were much. Most remained foodwaste after eating were soup and pot stew. The main cause of foodwaste production was overvolumne cooking. 88.8% of answers think that a menu can be useful to reduce foodwaste. The survey showed that 87.3% of answers put into the meter-rate bag after removed wetness of garbage. 84.1% of answers thought that the recycling of foodwaste needed, but the practical housewife was only 21%. For the suitable treatment of foodwaste, Survey showed that the consistent policy of goverment and continuous publicity was needed essentially, and that the public notice of TV or radio was effective. All of answers would like to participate in recycling of foodwastes whether public-posting or personal-posting. To set up vessel of posting at household, the proper purchase price and space of institution are needed, also the solution of sanitory & aesthetic problem and the collection of composting-product must be achieved smoothly.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.1
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• pp.58-66
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• 2004

The purpose of this study is to examine the possibility of reuse fermented foodwaste as a bulking agent in livestock waste and foodwaste composting. Aerobic composting device was added to the following sample : Foodwaste + Sawdust, Livestock feces+Sawdust, Foodwaste + Ferment, Livestock feces + Ferment. Temperature, pH, OM/N ratio, moisture, heavy metals, and microbes were measured in process of aerobic composting. The results of this study are following. 1. The composting period is determined in 16~24days, according to the change of temperature and OM/N ratio. 2. The salinity contents in compost of livestock waste and foodwaste ferment is about 0.5%, which can be solved the problems of salinity contents in foodwaste composting. 3. The proper ratio of livestock waste composting is 40% of cow feces to 60% of foodwaste ferment. 4. Processing expense of aerobic composting of foodwaste and sawdust is 40 won/kg composting expense of foodwaste and ferment is 30 won/kg. Fermented product composting can cut down the expense of bulking agent than others.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.91-97
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• 2000

The objective of this study was to evaluate the possiblity of Foodwaste and co-treatment with other waste for vermistabilization. The value of oxidation-reduction potential(Eh) of the dewaterized foodwaste by a plant of subatmospheric evaporation was a possitive(+) value indicating, but the values of pH, salinity was idicating an unfavorable condition for earthworm life. The paper mill mixing waste properties by ripening for 20days were changed into the favorable range for earthworm. The growth of earthworms in foodwaste and mixing waste of paper mill 30% was found to be 68%, 84% for the survival rate, 227%, 275% for the liveweight increasing rate, respectively. The ingestion rate of foodwaste and mixing waste of paper mill 30% indicate 0.72g/g·d, 0.81g/g·d, respectively. About 62∼75% of ingestion amount produce cast and characteristics of cast indicate pH 6.1∼6.5 organic component 34∼42%, salinity 0.35∼0.4, CEC 73∼94 me/100g, N, P, K concentration 0.8∼1.2%, 0.4∼1.6%, 0.43∼0.5% respectively. Therefore it can be evaluated that the casts are good soil condition and organic fertilizer.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.129-132
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• 2001

The purpose of this research was to understand possibility of foodwaste treatment by hybrid anaerobic reactor(HAR). The Possibility of methane utility and applicability of hybrid reactor system using foodwaste as substrate was investigated. The maximum loading rate and optimized operational conditions were determined. Hybrid anaerobic reactor was filled with packing material 50% of its total volume between the tube and the outer surface. The packing material used was randomly packed open-pore synthesis activated ceramic(SAC) media as support media for microbial attachment, growth, and chemical stability protected bacteria from effect of organic acid accumulation. In this research, although foodwaste has high concentrations C $l^{[-10]}$ and S $O_{4}$$^{2-}$ concentration the possibility of foodwaste anaerobic treatment was when foodwaste is treated by anaerobic digestion, this study focused on the possibility using C $H_4$ gas made under the anaerobic treatment as an alternative energy source. Other objective of this research is to study struvite formation and crystal forms in anaerobic digester. HAR is used to investigate phosphate crystallization without the addition of chemicals.

• Journal of environmental and Sanitary engineering
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• v.23 no.1
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• pp.49-56
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• 2008

Foodwaste will be able to treat is 13,000 ton/day. $18{\times}10^{13}$ won/yr are wasted with the foodwaste treatment. As a result, the initial working condition. These are given as follows : On the 1st. week, the foodwaste of the 130 ton/week(digest sludge : input foodwaste = 20 : 1) is being put into a DRANCO system by the space of 2 day. On the 2nd week, the food waste of the 130 ton/week(5 day) is being put into a DRANCO system by the space of 2 day. On the 3rd week, the foodwaste of the 130 ton/week is being put into a DRANCO system by the space of 3day. On the 4th week, the foodwaste of the 350 ton/week is being put into a DRANCO system. After that time, increase the quantity than last week is 10%. Under steady-state working condition, the methane content of the biogas is more then 55%. The $NH_3-N$ content of the digest sludge is under 3,500ppm. The VFA content of the digest sludge is under 1,500ppm. The pH is more then 8. The TS content of the digest sludge is $18{\sim}22%$. The VS content of the digest sludge is under 65%.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.84-89
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• 2003

The purpose of this study was to evaluate and improve the pre-treatment facility for foodwaste and sewage sludge mixture treatment. The process of foodwaste pre-treatment consists of storage, classification with crushing, and thickening. The effluent of sewage treatment facility was used as the diluting and washing water. The panicle size of foodwaste after pre-treatment was almost under 2mm, the mixture of foodwastes and sewage sludge showed an advantage to the anaerobic digestion. The amount of gas production increased from 0.8ton/day ($CH_4$ : 0.5ton/day) to 3.5ton/day ($CH_4$ : 2.3ton/day) after the anaerobic digestion of the foodwastes and sewage sludge mixture. The amount of sludge cake increased from 11.2ton/day to 21.2ton/day. Therefore, the proper operation of the foodwaste pre-treatment facility was contributed to the efficient anaerobic digestion of foodwaste and sewage sludge mixture treatment.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.2
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• pp.117-124
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• 2003

The purpose of this study was to investigate the optical conditions to satisfied the salt concentration of 1% below of compost produced by using the material of foodwaste and sawdust. We changed the mixing ratios of foodwaste : sawdust from 7:3 to 3:7 and the ratios of foodwaste : rice hull from 6.5:3.5 to 4:6. We analyzed C/N, pH, temperature, water content, volatile solid, salt, heavy metals to check the degree of composting. The running conditions of composting were $80{\sim}133{\ell}/min{\cdot}m^{3}$ of air flow rate, 1:4 of time interval(on:off) and 7days of turning interval. Running times were 28days. The optical mixing ratio of foodwaste : sawdust was 6:4 when we compared many factors. Especially when the mixing ratios of foodwaste : sawdust or foodwaste : sawdust were 7:3 or 6:4, the composting was not accomplished by the reason of low C/N. The concentrations of heavy metal were sufficiently low to satisfied the satandard of organic compost. The salt concentration was 0.43%-0.46% that was the half of initial concentration. The rice hull was the good in pore rate and 통기성, and so it can used alternative material.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.4
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• pp.651-657
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• 2016

The purpose of this research was to examine the possibility on the recycling of foodwaste leachate as external carbon sources using microbubble. The following operating conditions were selected: pressurizing tank 3 bar, circulation flow rate 3.65 LPM, and air flow rate 0.3 LPM with batch type. Microbubble contact time of 18 hours is optimal time to satisfy the recycling of foodwaste leachate as external carbon sources with batch type. HRT 18 hours came up to standard for external carbon sources, except for T-P concentration with continuous type. Coagulants need to be used for removal of dissolved phosphorus concentration by more than 88.5% of the total phosphorus concentration. The VFA was influenced by the organic decomposition rate and the concentration in the aerobic condition. It was considered that the VFA was needed for selection the optimal HRT or the addition of acid fermentation process in order to meet recycling standard of foodwaste leachate.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.10
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• pp.1028-1033
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• 2008

Sequential quick crushing and alkali hydrolysis(SeCAH), as a pretreatment for foodwaste, incorporating mechanical crushing and alkali hydrolysis was proposed and investigated in this study. Focuses were placed on the improvement of biodegradability of foodwaste and the estimation of potential inhibitors for anaerobic digestion. The solubility of the pretreated foodwaste by SeCAH was increased 2.5 times rather than mechanical crushing. Considering solubility improvement and energy consumption, 2,000 rpm of crushing strength and 5$\sim$10 sec of crushing time are recommended. After SeCAH, the fraction of large organic particles(>2.36 mm) of foodwaste was sharply decreased from 88.0% to 29.0%, otherwise the fraction of small particles(<75 $\mu$m) was greatly increased from 10.5% to 40.7%. Ammouinum, potassium and sulfate were estimated as potential inhibitors for anaerobic digestion and their concentrations in pig slurry were 3331.3 mg/L, 4256.5 mg/L and 1017.5 mg/L, respectively.