• Asian Journal of Atmospheric Environment
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• v.5 no.4
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• pp.228-236
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• 2011

Since most Green House Gases (GHGs) and air pollutants are generated from the same sources, it will be cost-effective to develop a GHGs reduction plan in combination with simultaneous removal of air pollutants. However, effects on air pollutants reduction according to implementing any GHG abatement plans have been rarely studied. Reflecting simultaneous removal of air pollutants along with the GHGs emission reduction, this study investigated relative cost effectiveness among GHGs reduction action plans in Busan Metropolitan City. We employed the Data Envelopment Analysis (DEA), a methodology that evaluates relative efficiency of decision-making units (DMUs) producing multiple outputs with multiple inputs, for the investigation. Assigning each GHGs reduction action plan to a DMU, implementation cost of each GHGs reduction action plan to an input, and reduction potential of GHGs and air pollutants by each GHGs reduction action plan to an output, we calculated efficiency scores for each GHGs reduction action plan. When the simultaneous removal of air pollutants with the GHGs reduction were considered, green house supply-insulation improvement and intelligent transportation system (ITS) projects had high efficiency scores for cost-positive action plans. For cost-negative action plans, green start network formation and running, and daily car use control program had high efficiency scores. When only the GHGs reduction was considered, project priority orders based on efficiency scores were somewhat different from those when both the removal of air pollutants and GHGs reduction were considered at the same time. The expected action plan priority difference is attributed to great difference of air pollutants reduction potential according to types of energy sources to be reduced.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.7
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• pp.845-851
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• 2003

The purpose of this experimental study is to investigate the quantitative pollutants reduction by oxygen enrichment and induced air effect in venturi type after-burner. For this purpose, CO, $CO_2$, $O_2$. and HC concentrations were measured before and after the after-burner by changing the Oxygen flow rate and area ratio which is defined as the ratio of air inducing area divided by total area. As results of this study, when the area ratio were increased, the emission reduction effect was increased even less oxygen flow rate. In that case when oxygen was injected too little, the pollutants were increased.

• Journal of Environmental Health Sciences
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• v.36 no.4
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• pp.306-312
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• 2010

This field study was performed to evaluate the efficiency of a plasma ion-operated air cleaner in temporal reduction of airborne pollutants emitted from a pig housing facility. In the case of gaseous pollutants, the plasma ion air cleaner was not effective in reducing levels of ammonia, hydrogen sulfide, nitrogen dioxide, or sulfur dioxide (p>0.05). In the case of particulate pollutants, however, the air cleaner was effective in reducing levels of particulate matter ($PM_{2.5}$ and $PM_1$) by 79(${\pm}6.1$) and 78(${\pm}3.0$)%, respectively. Unlike the case of these fine particle fractions, the reduction of total suspended particles (TSP) and $PM_{10}$ following treatment was almost negligible. In the case of biological pollutants, the mean reduction efficiencies for airborne bacteria and fungi were relatively low at 22(${\pm}6.6$) and 25(${\pm}8.7$)%, respectively. Taken together, these results indicate that in terms of air pollutants released from this pig housing facility, the plasma ion air cleaner was primarily effective in reducing levels of $PM_{2.5}$ and $PM_1$.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.E
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• pp.29-38
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• 1999

This study identified emission sources and emissions of air pollutants such as volatile organic compounds (VOCs), solvents, and acid gases produced from chemical plants. We collected air samples from various processes, reactors and facilities using VOC detectors and workers' experience. We identified chemical structures and emission concentrations of air pollutants. We analyzed total emissions of air pollutants emitted from the chemical plants. Also, we developed some emission reduction technologies based on chemical types and emission situations of the identified air pollutants. For reduction of air emissions of acid gases, we employed a method improving solubility of pollutants by reducing scrubber operation temperature, increasing surface area for effective contact of gas and liquid, and modifying or changing chemicals used in the acid scrubbers. In order to reduce air emissions of both amines and acid gases, which have had different emission sources each other but treated by one scrubber, we first could separate gas components. And then different control techniques based on components of pollutants were applied to the emission sources. That is, we first applied condensation and then acid scrubbing method using H2SO4 solution for amine treatment. However, we only used an acid scrubbing method using H2O and NaOH solution for acid gas treatment. In order to reduce air emissions of solvents such as dimethylformamide and toluene, we applied condensation and activated carbon adsorption. In order to reduce air emissions of mixture gases containing acid gases and slovents, which could not be separated in the processes, we employed a combination of various air pollution control devices. That is, the mixture gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower in sequence. In addition, for improvement of condensation efficiency of VOCs, we changed the type of the condensers attached in the reactors as a control device modification. Finally, we could successfully reduce air emissions of pollutants produced from various chenmical processes or facilities by use of proper control methods according to the types and specific emission situations of pollutants.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.264-272
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• 2007

Runoff of non-point pollutants has affected bad influence to water quality of river as reaching within short time. For this reason, reducing them prior to reaching aquatic systems or treating them after collection from discharge process of pollutants are desirable for efficient treatment of pollutants. This study was carried out to develop an ecotechnological method to prevent further aggravation of water quality by non-point source through vegetation filter strips. This study has placed a focus on improving infiltration capacity of soil for the optimum condition of vegetation filter strips. Therefore, we used titled soil filter strips instead of vegetation filter strips in this study. The three types of soil tilter strips were used in a bench scale experiment before applying to the field. The reduction efficiency of pollutants in soil filter strips (SS $84.5{\sim}92.5%$, BOD $67.9{\sim}80.6%$, T-N $43.4{\sim}76.6%$, T-P $40.6{\sim}87.4%$, Cu $28.3{\sim}48.1%$ Fe $92.1{\sim}97.7%$, Pb $81.4{\sim}97.3%$) was much higher than that of the controled group. And non-point pollutants reduction efficiency by soil filter strip's forms was estimated to be distinguishing in order of bio material, mixture of sand and gravel and lastly the whole gravel. In the event, the whole reduction efficiency of pollutants on the soil filter strips disclosed good results.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.4
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• pp.369-377
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• 2013

The trends of the criteria air pollutants' concentrations over Seoul are reviewed, relative contributions of major sources are discussd, and directions for future air quality management are suggested. It was shown that the yearly average concentrations of the criteria air pollutants except nitrogen dioxide and ozone have decreased significantly over the last three decades. Though the concentration of nitrogen dioxide has not decreased, the concentration of $NO_x$ has decreased significantly. The major reason for the reduction of the criteria air pollutants has been strict government regulations such as establishment of strict emission standards and switch to cleaner fuels. However, it is not clear the major reason (s) for the reduction of the $PM_{10}$ concentration. It is suggested that to further reduce the concentrations of secondary air pollutants such as ozone and $PM_{2.5}$, understanding the major chemical pathways for them is essential. In addition, influence from outside Seoul should be quantified and effectively controlled.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.1
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• pp.51-60
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• 1993

In order to study on the cause of visibility aggravation, we have selected the days of low-visibility observed in Seoul with haziness that was below 6km from 12 to 15 LST. According to the examinations, the number of low-visibility days satisfying the criteria is 30 days in 1989, 39 days in 1990, and 35 days in 1991, respectively. The annual number of low visibility days appears to increase mainly due to an increase in emission of air pollutants and in anthropogenic water vapor in the biosphere. The relationship between visibility and air pollutants(TSP, $NO_2, SO_2, O_3$) of selected days is also studied. Air pollution concentrations of selected days are much higher than those of other days. It is observed that the cause of visibility aggravation in Seoul is mainly smog and air pollutants. In particular, the visibility reduction and high $SO_2$ concentrations at Seoul in winter are similar phenomena that occurring with London smog, while the visibility reduction and high $O_3$ concentrations at Seoul in summer are also similar to the type of Los Angeles smog.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2004.11a
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• pp.319-322
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• 2004

The purpose of this study is to evaluate the reduction effect of bake out on the concentration of indoor air pollutants by measuring the concentration of indoor pollutants(VOCs, HCHO) after the bake out. As a result of the study, bake out was considerably effective in reducing the concentration o( indoor air pollutants, showing relatively high reduction ratio around 40${\sim}$56%. However, continuous attention and control after the bake out is required for the prevention of the rise of the concentration by subsequent emission.

• Journal of Korean Society on Water Environment
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• v.33 no.4
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• pp.474-480
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• 2017

This study was to estimate the reduction effect of nonpoint source pollutants according to the rainfall intensity and drainage of infiltration grate inlet. Soil infiltration flow was measured on-site and SS load by the filter part was calculated by the experimental data in laboratory reactor test. Soil infiltration flow was measured to be about $1m^3/hr$ in soil condition saturated with water. The filter part of the infiltration grate inlet was a hydraulic equipment unhindered by soil infiltration on the bottom of the storage tank, because the infiltration flow was measured to be about $3m^3/hr$ continuously in the closing infiltration hole condition. Infiltration flow and SS load were over about $1m^3/hr$ and 1.71 kg according to laboratory results by the filter part using the artifical sample. Therefore, the above values could be presented as the limitted value to start the reduction of filtration effect. Reduction efficiencies of SS load by the filter part for the rainfall intensity were about 87 % at 5 mm/hr and about 61 % at 10 mm/hr in consideration of one infiltration grate inlet got the drainage area about $200m^2$. The reduction efficiency of nonpoint source pollutants was very effective in the first flush rainfall. However, the reduction efficiency by rainfall density was higher than by flow.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.5
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• pp.468-476
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• 2005

The purpose of this study is to investigate actual air quality in newly-constructed multi-family houses and to improve Indoor Air Quality (IAQ). The field measurement was conducted in four different newly-constructed multi-family house complexes in Seoul and one existing multi-family house complex in Kyong-gi province. The result of the measurement shows that indoor concentrations of Formaldehyde and TVOC in newly-constructed multi-family houses are much higher than the foreign standards. To establish a proper process for reducing indoor air pollutants, various experiments have been conducted; application of natural materials, bake-out practice, closure of all openings without ventilation, and use of mechanical ventilation system. The result indicates that three practices (natural materials, bakeout, mechanical ventilation) can reduce the level of indoor air pollutants almost in half during the experiments. However, each practice has its limitation and is insufficient to satisfy IAQ standards. Therefore, the study proposes a proper reduction process of indoor air pollutants which combines four different practices in time sequence.