• Journal of Environmental Health Sciences
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• v.29 no.2
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• pp.56-61
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• 2003

This study was performed to examine the effects of chaff as a bulking material on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor of Control, Ch-1. Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4. respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wasted to chaff resulted in the reaction at higher reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff resulted in the more faster pH increase. The lowering of the volume ratio of food wastes to chaff resulted in the more faster reduction in the weight and the volume of wastes. Salinities were condensed by reaction days. The final salinity of Control and the final range of salinities of chaff mixtures were 2.79%, and 2.18~2.37%. respectively.

• Bulletin of the Korean Chemical Society
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• v.22 no.9
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• pp.943-944
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• 2001

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.208-212
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• 2003

This study was performed to examine the effects of chaff as bulking materials on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor Control, Ch-1, Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wastes to chaff resulted in the ascending of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff resulted in the more fast time of pH ascending. The lowering of the volume ratio of food wastes to chaff resulted in the more fast consistency in the weight and volume reduction rates. Salinities were condensed by reaction days. The final salinity of Control was 2.79%, and the final range of salinities of chaff mixtures was 2.18 - 2.37%.

• Journal of Environmental Health Sciences
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• v.34 no.6
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• pp.452-458
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• 2008

This study was undertaken to establish the biological reaction characteristics of the marine products industry wastewater which contains high concentrations of organic matter and saline. As the S/I is varied from 0.3 to 1.2, the results were follows : the observed ultimate anaerobic biodegradability varied from 72.0 to 88.0%, the first order reaction rate varied from 0.1735 to $0.3420\;day^{-1}$ and the second order reaction rate varied from 0.0132 to $0.0295\;day^{-1}$. When S/I was 0.9, the first order reaction rate had a maximum value, but the variations of the second order reaction rate were less than 1st-order reaction rate. When the operation time exceeded 2 days the gas production rapidly increased. The source of this rapid increase was due to that the activity of the granular sludge used in this study being faster than that of conventional sludge. Under aerobic condition, the characteristics of organic matter were as follows: the marine industry wastewater used in this study contained about 81% of biodegradable matter, and it was divided into readily biodegradable COD(Ss), slowly biodegradable COD(Xs), soluble COD(Si) and inert suspended COD (Xi). The percentages of each COD were 87.3%, 23.9%, 6.4% and 12.4% respectively.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.207-209
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• 2004

This study was performed to estimate the effects of salinity and washing of food wastes on temperature, pH, and salinity in aerobic composting of food wastes. Weight ratios of food wastes to water in washing were 1:0(Control), 1:1(W-1), 1:2(W-2), 1:3(W-3) and 1:4(W-4), respectively. Ratios of food wastes to wood chips in reactor of Control, W-1, W-2, W-3 and W-4 were 5kg:5L, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The increase in the ratio of food wastes to water used in washing resulted in the decrease of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the ratio of food wastes to water used in washing resulted in faster pH increase The final salinities of Control, W-1, W-2, W-3 and W-4 were 0.95%, 0.73%, 0.65%, 0.57% and 0.41%, respectively.

• Journal of Environmental Health Sciences
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• v.30 no.1
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• pp.1-6
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• 2004

This study was performed to estimate the effects of washing of food wastes on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Weight ratios of food wastes to water in washing were 1:0(Control), 1:1 (W-1), 1:2(W-2), 1:3(W-3) and :4(W-4), respectively. Ratios of food wastes to wood chips in reactor of Control, W-1, W-2, W-3 and W-4 were 5 kg:5 1, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The increase in the ratio of food wastes to water used in washing resulted in the decrease of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the ratio of food wastes to water used in washing resulted in faster pH increase and the steady state in the weight reduction rate and the volume reduction rate of composts. The final salinities of Control, W-1, W-2, W-3 and W-4 were 0.95%, 0.73％, 0.65%, 0.57％ and 0.41％, respectively.

• Journal of Environmental Health Sciences
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• v.28 no.2
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• pp.141-148
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• 2002

This study was performed to examine the effects of rice straw as bulking materials on temperature, pH, weight and volume reduction, porosity, C/N ratio, salinity, and conductivity in aerobic composting of food wastes. Volume ratios of food wastes to rice straw in reactor control, RS-1, RS-2, RS-2 and RS-4 were 4:0, 4:1. 4:2. 4:3 and 4:4, respectively. Reactors were operated for 24days with 1 hour stirring by lrpm and 2hours aeration per day. The values of pH of food wastes and rice straw were 4.39 and 7.4, respectively. The lowering of the volume ratio of food wastes to rice straw resulted in the high reaction temperature and the fast weight and volume reduction rates. C/N ratio in control was larger than that in rice straw containing reactors. Salinity and conductivity in reactors were condensed and increased by reaction days.

• YAKHAK HOEJI
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• v.44 no.1
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• pp.36-40
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• 2000

The photodegradation of pefloxacin, photolabile fluoroquinolone antibacterial agent, was studied. In the presence of $N_2$, photodegradation of pefloxacin was suppressed. The singlet oxygen and free radical generated in the reaction media proceeded photochemical reaction. The photodegradation of peflxacin was sensitized by benzophenone, a triplet state sensitizer.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.4
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• pp.457-468
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• 2013

Based on the activated sludge model(ASM), a mathematical model which represents the aerobic sludge digestion by sequencing batch reactor(SBR) combined with ultrasonic treatment was composed and performed in this study. Aerobic digestion using sequencing batch reactor(SBR) equipped with ultrasound treatment was also experimented for the purpose of parameter calibration. Most of the presented kinetic parameters in ASM or ASM2 could be used for the aerobic digestion of sludge but the parameters related in hydrolysis and decay rate needed modification. Hydrolysis rate constant of organic matter in aerobic condition was estimated at $0.3day^{-1}$ and the maximum growth rate for autotrophs in aerobic condition was $0.618day^{-1}$. Solubilization reactions of particulate organics and nitrogen by ultrasonication was added in this kinetic model. The solubilization rate is considered to be proportional to the specific energy which is defined by specific ultrasound power and sonication time. The solubilization rate constant by ultrasonication was estimated at $0.202(W/L)^{-1}day^{-1}$ in this study. Autotrophs as well as heterotrophs also decomposed by ultrasonic treatment and the nitrification reaction was limited by the lack of autotrophs accumulation in the digester.

• Bulletin of the Korean Chemical Society
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• v.1 no.1
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• pp.23-26
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• 1980

Direct photoisomerizations of benzalpyrrolinones yield the corresponding E-isomers via a singlet state, since no effect of oxygen on the reaction rates was observed. The Z-oxodipyrromethene was photoisomerized to the E-isomer in a degassed system. In an aerobic system the oxodipyrromethene 3 was photoisomerized at the early stage of the reaction and photooxygenated slowly at latter stage of the reaction. For bilirubin, other (possibly Z ${\to}$ E) than self-sensitizing $^1O_2$ reaction should have occurred because of the lack of a solvent effect on the self-sensitized photooxidation reaction rate at the early stage.