• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.75-80
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• 1997

This research has been examined to measure the degree of the fiber damage of ozonenation high yield pulp in the beating process. Ozone treated the TMP(Thermomechanical Pulp) and CTMP(Chemithermomechanical Pulp) of spruce and the CTMP of birch has been beaten to be reached 200ml(freeness) of its content. It had been studied the forming of fiber distribution by treatment for long fiber, short fiber, fine with the above method. As ozone treatment time gets longer, the pulp has showed the tendency of increasing the fiber content of 28, 48mesh. Ozone treated fiber has been increased long fiber content by being added softness. By given longer ozone treatment time, the TMP and CTMP of spruce has showed the decreasing of fiber content. On the contrary, CTMP of birch has showed the increasing its fiber content. It had proved that the results of difference are rather closer to the species of tree than closer to the kinds of pulp. The fiber content of over 200mesh which has created in beating process demonstrates the decreasing of its fiber content by getting longer ozone treatment time. The softness of fiber can be extracted by the lignin of fiber surface that had been formed by ozone treatment. Thus we assume that the fiber in the process of beating obtains less physical damage.

• Journal of Korean Society of Water and Wastewater
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• v.17 no.4
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• pp.567-573
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• 2003

The pretreatment process was carried out to solubilize the sewage sludge for enhancing its biodegradability using alkaline treatment, ultrasonic treatment(15kHz), ozone treatment and different combination of these three methods: alkaline followed by ultrasonic as well as ozone, and ultrasonic followed by alkaline. The solubilization efficiency was evaluated based on the SCOD/TCOD ratio and VSS/TS ratio. In results, the proper condition of alkaline treatment was shown as 30meq/l of NaOH, pH 12 and 3hours of reaction time. Solubilization efficiency increased to 17% from initial 2% based on SCOD/TCOD ratio under this condition. In ultrasonic treatment, the higher ultrasonic power, the longer treatment time and the lower sludge volume resulted in higher solubilization respectively. There was a rapid increase in solubilization efficiency after 20 minute, then it was measured as 32% of SCOD/TCOD ratio in 1 hour at a ultrasonic power of 1,300W with 1/sludge. Solubilization efficiencies in combined treatment using alkaline and ultrasonic were 47-53% higher than single treatment at a sonicated time of 1 hour. Ozone treatment followed by alkaline treatment also represented the enhanced solubilization compared to ozone treatment. Therefore, ultrasonic or ozone treatment assisted by alkaline could achieve the short treatment time as well as high solubilizetion efficiency.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.5
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• pp.511-516
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• 2008

Since 1989, Advanced drinking water treatment processes began to build in Korea, especially the water treatment plants around the Nak-dong river stream due to sequential pollutant accidents. Moreover, Advanced drinking water treatment processes, ozone and GAC, are again to be built in water treatment plants around Han-river stream to control taste and odor, micro pollutants. However, there are still a lot of discussion to decide the processes to apply for advanced treatment. Thus there are still need to understand clearly on the cost evaluation of each advanced treatment processes. The cost evaluation was accomplished based on the data of six water treatment plants which are currently being either operating or constructing. Exceptionally, PAC(Powdered Activated Carbon) process was evaluated with cost estimation from construction company. The capital cost per unit volume of ozone process was significantly decreased as the treatment capacity increased. The capital cost was in the order of GAC, ozone and GAC. The operation cost decreased in the order of PAC, GAC and ozone. The total cost considering present value shows that ozone process covers 84% of ozone and GAC process for $30,000m^3/d$ capacity while it covers less than 35% for over 140 thousands $m^3/d$ capacity. Comparing GAC only, and ozone/GAC process, ozone/GAC process is more cost effective for high capacity water treatment plant.

• Journal of Life Science
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• v.9 no.5
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• pp.590-595
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• 1999

The objectives of this research were to estimate variation characteristics of TOC, UV-254 and NH4+-N, etc, if odorous generated algaes flowed into water treatment plant and they contacted with ozone known as typical advanced treatment. It was estimated that pH decreased from initial 7.4 to 2.1 after ozone contact 100min. pH declined to early 10min. suddenly and then pH drop did almost occur. TOC and UV-254 continued to decrease with passed time of ozone contact. NO3--N concentration was much higher than NH4+-N and NO2--N for whole test period. Because ozone oxidized organic matters as various kinds of ion material and ion intensity of sample was extended, conductivity showed high as passed time of ozone contact. Owing to ozone oxidation of algae, color did almost disappear after ozone contact 20min.

• Journal of Industrial Technology
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• v.27 no.A
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• pp.25-29
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• 2007

Ozone alone, Ozone/GAC, Ozone/$H_2O_2$ and Ozone/GAC/$H_2O_2$ processes were introduced for treatment of humic acid, which is a representative refractory organic compound. $H_2O_2$ and GAC used as catalysts for experiment. The treatment efficiencies of humic acid in each process were analyzed for pH variation, DOC removal, and $UV_{254}$ decrease. $UV_{254}$ decrease in Ozone/GAC and Ozone/GAC/$H_2O_2$ processes were the highest with about 93%, and Ozone alone and Ozone/$H_2O_2$ processes were 88%. DOC removal in Ozone/GAC/$H_2O_2$ process was the highest with 71%. Removal by Ozone/GAC, Ozone alone, and Ozone/$H_2O_2$ processes were 66%, 39%, and 47%, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.5
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• pp.573-576
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• 2006

The efficacy of integrated ozone oxidation-biodegradation treatment was examined in the treatment of petrochemical wastewater with a special focus on the overall treatment time. When raw wastewater with chemical oxygen demand(COD) of 70-80 mg/L was oxidized by ozone, approximately 20% of initial COD was removed in less than 1.5 min at a dosing rate of 400 mg $O_3/L{\cdot}h $. No further decrease in COD was observed for the extended ozone treatment up to 30 min. Biological treatment alone showed a rapid reduction of COD to 40-50 mg/L, subsequently resulting in the decreased rate of COD removal. Pre-treatment by ozone before biological treatment did not significantly affect the specific rate of COD removal in a biological treatment. When ozone oxidation followed biological treatment, the extent of COD removal by ozone oxidation was greater compared to that of biologically-treated wastewater for a shorter time. Taken together, it was decided that the biological treatment time could be reduced if the treatment processes of concern will be properly arranged.

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.41-49
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• 1999

The water treatment by was performed to remove VOC and organic substances in the multi-stage ozone contactor. Ozone is mainly utilized to change the chemical structures of organic substance, of which finally has the purpose to degrad them. The removal efficiency of VOC has 20~60% at the ozone concentration of 3 ppm, in case of trichloroethylene, its efficiency is reduced by 85% at the ozone contact time of 8 min. Design factors such as the number of stage, ozone concentration, zone contact time are determined for optimal treatment in the multi-stage contactor.

• Journal of Food Hygiene and Safety
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• v.10 no.1
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• pp.45-51
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• 1995

Ozone treatment was applied to ginseng powder for the improving hygienic quality of ginseng powder. A bacterial strain was isolated form ginseng powder contaminated. The strain designated as GT4, was identified as Escherichia coli species by IMVIC test method. Ozone inhibited strongly total bacteria and coliforms in ginseng powder(initial concentration 103/g) at 0.35 ppm. High ozone concentration reduced death time of the total bacteria in ginseng powder. However, ozone treatment caused significant degradation in saponins of ginseng powder. Ozone treatment also caused a increase in Hunter's color L value and decrease in a and b values of ginseng powder.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.438-441
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• 2000

Ozone has the advantages for the strong oxidant agents. Ozone is widely used as a disinfectant and deodorant in water treatment and biosafety cabinets. We attempted deodorization and disinfection in the piggery using ozone treatment. It was found that ozone affects deodorization of ammonia and decrease of microbial organism in the air. Concentration of ammonia decreased 50 percents and microbial organisms in the air were decreased below 10 percents. It will be useful for the application of the ozone to environmental treatment in the piggery.

• Polymer(Korea)
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• v.27 no.2
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• pp.98-105
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• 2003

The surface energy and the effect of functional groups on the surface of the ozone-treated low-density polyethylene (LDPE) film were studied. Treatment conditions were treatment time, total amount of transferred ozone, and ozone concentration. The introduction of polar groups on the surface of LDPE film after ozone treatment was confirmed by FTIR-ATR and XPS analyses. Surface fee energy of the LDPE film was examined by a contact angle method. The ozone treated-LDPE film showed a decreased water contact angles about 15$^{\circ}$ mainly due to the increased concentration of oxygen-containing functional groups, which was attributed to the increased surface free energy or $O_{IS}/C_{IS}$Also, the concentrations of the oxygen-containing functional groups on the surface of LDPE film increased with ozone treatment time and concentration, whereas no significant effects were found for the total amount of transferred ozone. From the dyeability test using Kubelka-Munk equation, it was found that the ozone treatment plays an important role in the growth of oxygen-containing functional groups of LDPE film, resulting in the improvement of dyeability for basic dyeing agent.