• Journal of the Korean GEO-environmental Society
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• v.15 no.9
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• pp.13-18
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• 2014

BMP test was carried out to evaluate the characteristics for co-digestion of night soil and food waste. 6 types of sludge were tested in 30 days which were raw, excess, digested, night soil/septic tank (1:1), food waste (food : dilution water = 1:1), and mixed sludge. Bio gas was produced actively after 2 days, and continued in 2 weeks. Gas generation amount was decreased rapidly after considerable space of time. Especially maximum productivity of gas was shown in 7~8 days. The ultimate methane yields of raw, excess, digested, night soil/septic tank, food waste, and mixed sludge were 64.63, 67.49, 66.45, 72.44, 107.85, and 46.71 mL $CH_4/g$ VS respectively from Modified Gompertz model. The lag growth phase time and maximum specific methane production rate of mixed sludge were 1.88 day and 80.4 mL/day respectively. The methane potential of mixed sludge was higher than individual sludge. So high methane potential was expected by controlling mixing ratio of food waste. Besides stable operation of digestion tank and the solution of oligotrophic problem were possible.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.71-78
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• 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 the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.15-25
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• 2022

In this study, the efficiency of treatment of moisture and organic matter in food waste was analyzed according to the air blast volume and preheating using the bio-drying method. Te mount of air blast volume and preheating were determined by the evaluation of temperature and CO2 during food waste treatment using the bio-drying method. As a results, the increase in the air blast volume increased the moisture removal efficiency and removal rate, but, lowered the temperature inside the bio-drying by the decease in microbial activity. In order to maintain the activity of microorganisms, it was estimated that it was necessary to inject an appropriate air blast rate according th the properties of the food waste. In this study, the injection of air blast volume at 15L/min was optimal. It was evaluated that the organic matter and water removal rates according to the presence or absence of air preheating, the organic matter removal rate and water removal rate increased by 3-5% when air preheating was not performed. Also, there was no internal aggregation caused by the generation of condensate inside the bio-drying. Therefore, for effective bio-drying of food waste, it is necessary to maintain an appropriate air blast volume to maintain microbial activity, and it is considered that injection through preheating of air is required.

• Journal of Environmental Impact Assessment
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• v.17 no.5
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• pp.263-270
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• 2008

The purpose of this study was to investigate the characteristics of the temple wastes and suggest the waste management guidelines for temples in natural parks. Study results revealed four important findings. First, it was found that the average quantity of the total temple wastes was 85,786g/day which was composed of general wastes(44,617g/day), food wastes(20,292g/day), recycling wastes(20.825g/day), and buddhist service wastes(60g/day). The average generation per capita of the temple wastes was 1,511g/capita day and the average bulk density was 0.102kg/l. Second, the food scrap was of small quantity(72.5g/day) because the traditional buddhist eating method, "Baru meal(鉢盂供養)" prohibits food abuse. This amount is very little compared to that produced in the general household in Korea. Third, the average quantity of the buddhist service wastes was 300-1,650g/one time. This wastes occupied 0.07% of the total temple wastes. Fourth, the average waste generated by visitors was 182.8g/person, which occupied 87.1% of the total temple wastes and costed 52,100,000 Wons to treat.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.67-76
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• 2021

Biogasification is a technology that produces environmentally friendly fuel using methane gas generated in the process of stably decomposing and processing organic waste. Biogasification is the most used method for energy conversion of organic waste with high moisture content, and is a useful method for organic waste treatment following the prohibition of direct landfill (2005) and marine dumping (2013). Due to African Swine Fever (ASF), which recently occurred in Korea, recycling of wet feed is prohibited, and consumers such as dry feed and compost are negatively recognized, making it difficult to treat food waste. Accordingly, biogasification is attracting more attention for the treatment and recycling of food waste. Korea's energy consumption amounted to 268.41 106toe, ranking 9th in the world. However, it is an energy-poor country that depends on foreign imports for about 95.8% of its energy supply. Therefore, in Korea, the Renewable Energy Portfolio Standard (RPS) is being introduced. The domestic RPS system sets the weight of the new and renewable energy certificate (REC, Renewable energy certificate) of waste energy lower than that of other renewable energy. Therefore, an additional incentive system is required for the activation of waste-to-energy. In this study, the operation of an anaerobic digester that treats food waste, food waste Leachate and various organic wastes was confirmed. It was intended to be used as basic data for preparing the waste-to-energy incentive system through precise monitoring for a certain period of time. Four sites that produce biogas from organic waste and use them for power generation and heavy gas were selected as target facilities, and field surveys and sampling were conducted. Basic properties analysis was performed on the influent sample of organic waste and the effluent sample according to the treatment process. As a result of the analysis of the properties, the total solids of the digester influent was an average of 12.11%, and the volatile solids of the total solids were confirmed to be 85.86%. BOD and CODcr removal rates were 60.8% and 64.8%. The volatile fatty acids in the influent averaged 55,716 mg/L. It can be confirmed that most of the volatile fatty acids were decomposed and removed with an average reduction rate of 92.3% after anaerobic digestion.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.4
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• pp.112-120
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• 2004

In this study, the physico chemical characteristic of MSW and sludge in west area of Kangwondo was investigated for database, managing the waste and waste treatment facility. The sampling sites were selected as 6 different MSW generation area and 2 sludge generation area. it is necessary to measure the characteristics of MSW to build the data-base. The year of 2000, 197.4ton/day of MSW which was generated in this area. This MSW was composed of 26.6% food wastes, 24.2% of papers, 22.8% of plastics & vinyls, 9.6% of textiles, 3.80% of wood, 2.8% of rubbers & leathers and others, respectively. Most of MSW are composed of food, paper and plastic waste and combustible waste is more than 89%. The generation of papers and vinyls are almost same for different seasons For 3-components of MSW, moisture is 40.2%, combustible component is 52.1% and ash is 7.7% and for 3-components of sludge, moisture is 83.3%, combustible component is 7.7% and ash is 9%. The chemical element has the high order of carbon(51.6%), oxygen(38.6%), hydrogen(7%) on the dry basis of wastes. And the high heating value of MSW is 4989.4 Kcal/kg sludge is 4428.04 Kcal/kg and low heating value of the MSW which is measured by calorimeter is 2032.88kcal/kg. From the leaching test of wastes, there is no heavy metals.

• Proceedings of the KIEE Conference
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• 2005.11a
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• pp.207-209
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• 2005

Ultra wide band electromagnetic energy can be transmitted to a far field by emitting the nanoseconds high voltage pulse electromagnetic energy via an antenna. This UWB EM energy is expected to be used in post-packing pasteurization of food, detection of buried objects or underground water veins and caves and the treatment of waste water or polluted gas. The nanoseconds pulse forming for UWB generation using high voltage blumlein line and an ultrafast switch is mentioned.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.87-97
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• 2021

This study was conducted to prepare an incentive system (proposal) for the activation of waste-to-energy. Weights for each type of energy use were prepared by conducting prior research and economic analysis. In addition, the waste-to-energy incentive (proposal) was calculated in consideration of energy efficiency for each type of energy use. As a result of economic analysis of 11 biogasification facilities, the B/C value was found to be very diverse, ranging from 0.16 to 1.69. In terms of benefits, imports of waste treatment import fees were very high at 68.4 to 99.3% of the total, and four facilities with a surplus (+) or higher in the management balance. In order to convert energy consumption into units of sales volume, 0.58 Nm³/KW for power generation, 0.17 Nm³/kg for steam, and 1.00 Nm³/Nm³ for external supply were calculated using the 'scale factor'. The 'weight factor' was calculated as 0.249 for power generation, 0.656 for steam, and 0.806 for external supply, respectively, by use type.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.2
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• pp.22-27
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• 2011

This study was performed to find out the optimum condition for hydrogen production by changing mixture ratio from 3:7(food waste water : swine wastewater) without pre-treatment of food wastewater and swine wastewater using a continuous reaction process. It was confirmed that hydrogen generation according to pH is the highest in a condition of pH 5.5, and that the optimum pH for hydrogen production in case of mixing food wastewater with swine wastewater is 5.5 through this. Hydrogen generation according to HRT showed high hydrogen generation rate in case of 4 days rather than 3 days, and this involves largely in vitality of hydrogen producing bacteria according to variation of the HRT value, so it is judged that HRT also acts as an important factor to hydrogen producing bacteria. The organic removal efficiency recorded a removal efficiency of maximum TS 52%, VS 71%, TSS 83% and VSS 89% at the 6th day of operation, and it was confirmed that organic removal efficiency is possible even through an hydrogen production process.

• Journal of the Korean GEO-environmental Society
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• v.10 no.2
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• pp.13-20
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• 2009

There have been increasing interests in the odor generation problems as concerns about the quality of life has been increased recently. Especially, approximately 67% of the odor complaints from environmental facilities are those from sewage treatment facilities and food waste treatment facilities. Moreover, sewage ocean dumping will be prohibited from 2012 by the international and domestic ocean laws, and thus, demand for alternative management plans is increasing. Therefore, it was first selected 5 sewage treatment facilities and 5 food waste treatment facilities where the amounts of waste are relatively immense in Busan, and collect their sludge samples. Then it was investigated the samples' physical and chemical characteristics through proximate analysis, elemental analysis, XRF analysis, and calorific value analysis. Finally, estimate the $H_2S$ emission rates were estimated in order to apply the results as the basic data for providing the fundamental solution for the oder complaints. As a result, the concentration of $H_2S$ in sewage sludge and in food waste treatment facility were 57.3 mg/kg and 19.7 mg/kg in average, respectively. Finally, the units of $H_2S$ in wastes stored in total 10 waste treatment facilities was estimated 16,017,910.0 mg/d.