• Resources Recycling
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• v.18 no.6
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• pp.10-17
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• 2009

Degradation of the organic component in the waste were carried out by superheated steam in a pressurized vessel. The effects of waste characteristics, reaction temperature and residence time on the degradation rate have been determined. The biodegradable organic components such as food and paper waste have been degraded, and plastics, wood and metal were remained without degradation. The degradation efficiency is decided by the desizing rate of the waste, and the waste mixture with 23% biodegradable organic component shows higher desizing rate than that of the 43% of the biodegradable organic component in a short residence time and the desizing rate is found to be 90% in the maximum condition.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.286-291
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• 2001

As part of fundamental studies on the degradation of the organic compounds in industrial waste water, the photocatalytic degradation properties of the organic compound by means of the UV/TiO$_2$degradation process have been investigated. The test organic compound of acetic acid was chosen in this study. The testing of photo catalytic degradation were performed under various operation conditions such as TiO$_2$dosages, initial concentration of the organic, the aqueous pH's, etc. The effects of various parameters on the short time activity of the present acetic acid-UV/TiO$_2$system could be demonstrated from this investigation.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.4
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• pp.363-368
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• 2010

The overall indicator of microbial activity in the fermentation-extinction reaction of food waste by using bio wood-chips were investigated by considering adenosine tri-phosphate(ATP). Degradation rate of organic compounds, which was represented by chemical oxygen demand(COD) and total nitrogen(TN), was increased with the concentration of adenosine tri-phosphate during fermentation-extinction reaction of food waste by using bio-wood chips. With this view, the ATP would be one of the overall evaluation indicator of organic degradation in the species of bio-wood chip for the fermentation-extinction of food waste.

• KSBB Journal
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• v.25 no.1
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• pp.103-107
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• 2010

Oil degradation agent was developed with organic sludge and modified peat moss (MPM) to recover oil contaminated soil. Waste sludge discharged from wastewater treatment plant of chemical plant in Ulsan National Industrial Park was used as organic sludge, and MPM was purchased. Organic sludge was adequate to use as growth medium for microorganism, the surface of MPM had porous structure which could enhance the cultivation condition of oil degradation microorganisms. Water contents and TPH variation with time were observed to investigate the degradation capacity of developed degradation agent. Water contents were rapidly decreased with higher contents of MPM, however, in case of TPH, high MPM content decreased the degradation capacity. Therefore, it was recommended that the content of MPM was controlled to below 10% in degradation agent as mixing organic sludge with MPM.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.109-118
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• 2001

In the stage of aftercare in waste landfill management, it is very difficult to estimate the decomposition of landfill waste by excavation which damages the low permeability layer. This study developed the method to analyze the amount of landfill waste degraded bio-chemically as the types of leachate and gas, and applied the method to Nanjido landfill(NL). Application result showed that 70% of high biodegradable waste in NL was transformed to gas and leachate by 2000. Also this study suggested that the transformed portions of waste name for "Decomposition Index" at that time and the proposed method must be modified according to the biological condition of waste degradation.

• Journal of Environmental Science International
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• v.27 no.12
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• pp.1205-1214
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• 2018

During the past few decades, significant increase in the consumption of coffee has led to rapid increase in the production of coffee waste in South Korea. Spent coffee waste is often treated as a general waste and is directly disposed without the necessary treatment. Spent Coffee Grounds (SCGs) can release several organic contaminants, including caffeine. In this study, leaching tests were conducted for SCGs and oxidative degradation of caffeine were also conducted. The tested SCGs contained approximately 4.4 mg caffeine per gram of coffee waste. Results from the leaching tests show that approximately 90% of the caffeine can be extracted at each step during sequential extraction. Advanced oxidation methods for the degradation of caffeine, such as $UV/H_2O_2$, photo-Fenton reaction, and $UV/O_3$, were tested. UV radiation has a limited effect on the degradation of caffeine. In particular, UV-A and UV-B radiations present in sunlight cause marginal degradation, thereby indicating that natural degradation of caffeine is minimal. However, $O_3$ can cause rapid degradation of caffeine, and the values of pseudo-first order rate constants were found to be ranging from $0.817min^{-1}$ to $1.506min^{-1}$ when the ozone generation rate was $37.1g/m^3$. Additionally, the degradation rate of caffeine is dependent on the wavelength of irradiation.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.234-238
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• 1998

Anaerobic degradation characteristics of dewatered liquid of household food waste including methane conversion efficiency and degradation kinetics were studied in an anaerobic batch reactor of 5 L volume. The ultimate methane production for dewatered liquid of household food waste tested was over 0.31L $CH_4/L{\cdot}dewatered$ liquid of household food waste. The kinetic constant of dewatered liquid of household food waste tested was $0.223d^{-1}/L$. The kinetic behavior of anaerobic degradation was described as a first order series reaction. The determinant of rate-limiting step(DR) that is balanced out from the rates of reaction steps was defined by the logarithmic difference of the maximum acidification rate and the maximum methanation rate. Anaerobic degradation characteristics of organic materials were evaluated by the value of DR. The DR of dewatered liquid of household food waste tested was 1.17.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.570-576
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• 2001

Thermophilic aerobic bacteria were applied in the degradation of industrial waste activated sludge (WAS) on a laboratory scale expreiment. The performance of digestion was estimated by measuring the reduction of total suspended solids (TSS), dissolved organic carbon (DOC), and total organic carbon (TOC). Among three strains of Bacillus stearothermophilus and three strains of Thermus species, B. stearothemophilus ATCC 31197 showed the best overall efficiency level for the degradation of industrial WAS, which was collected from a wastewater treatment plant in an oil refinery factory. Industrial WAS coul be successfully detraded in a batch digestion with ATCC 31197. The stability of the digestion process with ATCC 31197 was successfully verified by semi-continuous (fill-and-draw) digestion experiment. From the results of this study, it was shown that the thermophilic aerobic digestion process with ATCC 31197 could efficiently be applied to the degradation of industrial WAS.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.199-215
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• 1992

Sources of organic waste materials for aerobic and/or anaerobic degradation, or for composting of solid wastes in Germany were estimated. The basic microbiology and the energetics of these processes were compared with special emphasis on anaerobic degradation, for which a general degradation scheme of carbohydrates is presented. Advantages of anaerobic over aerobic treatment processes are pointed out and conditions for maintaining a highly stable anaerobic process as well as producing a sanitized, hygienic product are discussed. Reactor systems suitable for efficient treatment of wastes with a high or low proportion of suspended solids are principally compared and results of laboratory studies on the degradation of several wastes and animal manures summarized. Finally, a piggery slurry treatment factory for an ultimate slurry processing to obtain a dry fertilizer and a harmless, disposable liquid, as it is in operation in Helmond/Holland, is presented and preliminary process data are presented.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.4
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• pp.141-150
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• 2006

To develop the microbial agents for the environmentally-friendly treatment and recycling of food waste, useful microorganisms, which showed higher degradation activities to various organic compounds and possessed flocculating activities, were isolated from the earthworm. One of the isolated strains, named JS-01, was further selected due to its higher flocculating activity against 0.5% Kaolin clay. JS-01 was identified as Bacillus pumilus sp. by 16s rDNA analysis. The optimal temperature and pH for the growth of JS-01 to express the flocculating activity was found to be at $37^{\circ}C$ in pH 7.0 of EPS broth medium. JS-01 also expressed good degrading activity against cellulose, which is one of the representative organic materials in food waste. We propose that JS-01 will be a good candidate for the efficient treatment of food waste and leachate due to the property to degrade cellulose and flocculating activity.