• Journal of the Korea Organic Resources Recycling Association
• /
• v.10 no.1
• /
• pp.96-101
• /
• 2002

This research was conducted to find the optimal condition in codigestion of food waste and sewage sludge with various mixing ratios. The analysis of degradation characteristics were based on the variations of methane production as well as methane production rate (MPR). BMP values were getting higher as the addition of foodwaste increased. But the lag-phase were prolonged when the foodwaste was over 40%, Nonlinear regression was conducted with the cumulative methane production data. Not only thermophilic but mesophilic condition, 40% of foodwaste addition showed maximum MPR. Higher mixing ratio which is over 50% were unprofitable in gaining higher MPR values. The most important factor in thermophilic co-digestion was substrate concentration. But in mesophilic co-digestion, both substrate concentration the mixing ratio had major effects on MPR. The most probable reasons of the synergetic effects in co-digestion of foodwaste and sewage sludge were the balanced nutrient expressed as C/N ratio and increased kinetic constants of hydrolysis by the mixed co-substrates.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.19 no.2
• /
• pp.55-69
• /
• 2011

Use of disposer at the kitchens of Korean apartments is inevitable in treating their foodwaste having a water content of more than 80%. Also we have to ensure that this extra disposer-foodwaste BOD loadings be treated properly by installing/operating a pre-treatment system before this wastewater enters public sewer system. However, the degree of BOD removal should not be excessive since a BOD/N ratio higher than 5 is required for removing N/P at a municipal wastewater treatment plant. The removal of BOD/N in the pretreatment system rather than BOD alone can be an alternative solution in solving this problem. The particles separated by sedimentation, screen or packed-bed can be anaerobically digested at apartment sites to generate biogas that can be used for simple digester heating and to generate volatile fatty acids (VFAs) for nitrogen removal. We suggest that Korean government grants a temporary license (say for 5 years) to foodwaste treatment companies in collaboration with apartment construction companies which may do business and develop various kinds of disposer-foodwaste treatment systems in diverse wastewater discharge systems of Korean apartments.

• Proceedings of the Korean Institute of Resources Recycling Conference
• /
• 2001.05b
• /
• pp.109-112
• /
• 2001

A case study of foodwaste treatment was conducted to compare the impacts of four scenarios: incineration, incineration after biogasification, biogasification followed by composting, and composting. Potential contributions to climate change, acidification, consumption of landfill and human toxicity were assessed. Characterization of human toxicity caused by metals and PCDD/DF was performed by three multimedia fate models. Scenarios with a biogasification process showed lower impact on climate change and human toxicity. The ranking of four scenarios on human toxicity varied depending on the characterization models applied. The steady state models placed high priority on emission of heavy metals to farmland, whereas the dynamic model estimated the emission of PCDD/DF from the incineration process as more significant.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.5 no.1
• /
• pp.43-52
• /
• 1997

This study was conducted to analysis citizen's attitude and style to the foodwaste from loth Sept. to 30th Sept. in 1996. The research was used questionare method and the analysis was used prequency analysis and cross table method by SPSS (scientific statistics). they answered that the most serious environment problem was waste problem and the best way to settle waste problem was to reduce waste production itself. And they answered that to settle environment problems, it was most important for us to change our life style. But It was not agreed between consciousness and action(execution). Because most of the food-related waste was among household waste, it's settlement was the most importment thing than any other. Nevertheless the seperation of waste was essential to effective incineration, the seperation process was not actually conducted and only a few housewife knew the difference of incinerable and non-incinerable waste. The recycling for the disused dry-cells and garbage is not completly. But we think that if the effective government's recycling counterplan for wastes, foodwaste or wasted dry cell, etc., is estabilished, rates of seperation and collection was increasing. Much usuage of onetime vinyl bag for shopping was become the one of the main cause in increasing the package waste, and so it was needed to use the longlife shopping basket.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.14 no.2
• /
• pp.71-82
• /
• 2006

This study was carried out to assess and analyze the overall problems of the facilities in recycling and treating of foodwaste on the basis of the unit operation facilities. It proposes effective alternatives for the high profitable management that can meet the regulation of the facilities. The study is composed of several parts including a collection of academic reports, field studies regarding the facilities operated by local government and the private sector, the analysis on odor samples from compost facilities and processing facilities for animal feed from foodwaste. Twenty facilities were surveyed on the field to find out the existing problems and to compare between facilities. Several facilities didn't meet the governmental regulation on some processes, especially the stages of input, storage, odor control and the qualities of final products under the unit equipment operation. The analysis on the odors from the phases of input, shredding and fermentation of a compost facility and processing facilities for feed, the odors from shredding equipments were higher in concentration than the others. The Major odors from the composting facility contained hydrogen sulfide ($H_2S$), methyl mercaptan ($CH_3{SH}$), Dimethyl sulfide ($(CH_3)_2S$) and Ammonia ($NH_3$) and the major odors from the animal feed facility contained methyl mercaptan ($CH_3{SH}$), Trimethylamine ($(CH_3)_3N$) and Acetaldehyde ($CH_3CHO$).

• Journal of the Korea Organic Resources Recycling Association
• /
• v.13 no.1
• /
• pp.71-78
• /
• 2005

This study was performed to obtain the basic data on current situations and challengeable aspects of vermicomposting industries in Korea and to develope foodwaste treatment technology using earthworm. Pre-treatment process of food waste consists of cleaning, grinding, mixing and others, and salinity of food waste was 0.7% on average, thus not suitable for feed of worms. When applying wash water and going through the cleaning process, however, salinity was dropped to 0.38%, indicating that cleaning process applying wash water is necessary to control the proper salinity for growth of worms. In the food waste processing experiment applying worms, it has been presented that smaller particles induce higher processing efficiency. As a result, food waste processing by worms is possible through maintaining the suitable environment for survival of worms from input process to generation of cast. Cast generated after processing food waste was proved to be most suitable for product standard of compost thus cast is presented to be recycled after processing the food waste applying the worms.

• Journal of Environmental Impact Assessment
• /
• v.21 no.3
• /
• pp.353-365
• /
• 2012

This study is understanding characteristics and analyzing contributions of the odor causing compounds of complex-odor & major specified odor materials, and contribution analysis, caused pre-treatment facilities(input and storage) and post-treatment facilities(heating and drying). The target of this study is feeds-production-facilities, located in Seoul. The averaged complex-odor compounds on the boundary line is 21 times higher, and it is 15 times higher than emission standards. In cracking&collection(pre-treatment facilities), the concentration of compounds is 4,881 times, 2,080 times in drying, and 1,442 times in putting&storing facilities. Ammonia occupies the largest portion of the results of monitoring specified odor compounds in input&storage facilities, followed Acetaldehyde > Hydrogen sulfide > Methyl mercaptan. In cracking&collection, Ammonia also occupies most of odor compounds, followed Methyl mercaptan > Acetaldehyde > Dimethyl disulfide > Dimethyl sulfide > Hydrogen sulfide. Acetaldehyde > Methyl mercaptan in drying facilities. On the boundary line, however, the concentration of specified odor compounds stays below emission standards. The result of contribution analysis is that methyl mercaptan has the highest contribution in input & storage, as well as cracking&collection facilities, followed Acetaldehyde > Hydrogen sulfide > Dimethyl sulfide > Dimethyl disulfide. In the drying facilities, the contribution shows Methyl mercaptan > Acetaldehyde > i-Valeraldehyde and Butyraldehyde. Therefore, to decrease odor in foodwaste treatment facilities, proper prevention facilities need to be installed and operated, according to characteristics of individual odor compounds, based on monitored data.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.19 no.2
• /
• pp.33-40
• /
• 2011

This study was conducted for the purpose of examining stable disposal of foodwaste and possibility of multilateral use of its by-product by mixing earthworm powder and by-product generated from food waste disposal for making feed for sea fish. As a result of the study, content of crude protein (25.93%, 69.72%), crude lipid (16.91%,6.39%) crude ash (15.38%, 5.30%) in by-product of food waste and earthworm powder was higher than that in fish meals manufactured in the country, and it was judged that it is available to make good feed as a source of fatty acid as it contained C18:1n9c, 1n9t and c16:0. As for stability as a raw material for feed, it was shown that the stability was high when using the product as a raw material for feed not exceeding the standard of test items, and though change of content and ingredients to mixing ratio, it was shown that mixed specimen of fertilizer (S6) was higher, showing that it has great utilization in the future. Also, as it has more content of registered ingredients than any other raw materials for feed manufactured in the country, it is possible to be used as a substitute when manufacturing feed for sea fish. Therefore, it is judged that various studies such as economic analysis and technology of possible manufacturing will be needed in the future.

• Applied Chemistry for Engineering
• /
• v.23 no.1
• /
• pp.28-34
• /
• 2012

In this study, we operated a UASB (upflow anaerobic sludge blanket) reactor by using foodwaste leachate as a raw material with the method of Mesophilic Digestion ($35{\pm}0.5^{\circ}C$) and Thermophilic Digestion ($55{\pm}0.5^{\circ}C$). During 20 days of operating time with the Mesophilic Digestion, the recirculation ratio of effluent was stepwisely changed in every five days. Thermophilic Digestion was carried out at the same condition for Mesophilic Digestion. Results showed that the organic removal efficiency of Mesophilic Digestion was over 90% and the yield of methane production was from 66 up to 70%. The organic removal efficiency of Thermophilic Digestion was over 80% and the yield of methane production was between 62 to 68%. Also, when UASB reactor was operating to over the 3Q effluent recirculation, the experiment could be carried out economically and stably.

• The Korean Journal of Food And Nutrition
• /
• v.12 no.3
• /
• pp.246-251
• /
• 1999

The purposed of this study was to investigate the efficient recycling of food waste according to the restaurants type. To the investigated of characteristic of food wastes in different types of restaurants we were collected the sample of 60 as Korean 35 Chinese 10 Japanese 5 Western 5 Flour 5 in Swoon. The average water content of food waste was 79.9% and Korean restaurant was 80.3% which was hig-her than that of any other serving type. On the examination of a organic matter content of food waste according to the season crude fiber was higher in may and July crude protein content was higher in January and march than that other seasons. The average pH of food waste was 4,74 C/N ratio was 15.8 and the average cation content was K 0.57% Ca 0.39% Mg 0.22% NaCl 3.36% respectively The aver-age concentration of Fe, Zn, Pb, Cu, Cr, Cd Ni were 154.37 mg/kg 24.79 mg/kg 0.27 mg/kg 5.63 mg/kg 5.49 mg/kg, 0.31mg/kg 1.07mg/kg respectively.