• KIEAE Journal
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• v.5 no.3
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• pp.41-48
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• 2005

Before occupation of an apartment housing, the builders are required to inform the test result of IAQ to the public. However, there is no simplified method to predict IAQ before measurement of pollutant concentration. In this study, a simplified way of predicting IAQ based on the distribution of indoor pollutant concentration is proposed. 7 different cases of air change rate have been simulated through CFD analysis to get the distribution ratio of each pollutant material and then simplified functions were used with CRIAQ1 values derived from CFD simulation to evaluate by comparing the influence of each material in the indoor pollutant concentration. Again, a lot of efforts which can improve the indoor air quality have been performed. Materials used in indoor space are labeled with their pollutant emission level. Installation of ventilation system in residential buildings will be regulated by a building codes sooner or later. But it is important to understand the fact that layout of walls, location or size of openings will influence the indoor air flow and pollutant concentration. And location of emitting material influences to indoor air pollutants distribution. But until now there is few recognition and consideration of these factors. Therefore, in this paper the effects of these factors is proved and some kind of guideline is made for designers after a comparison of typical apartment floor plan and a new type plan with their average pollutant concentration and its distribution of each room. CFD(Computational Fluid Dynamics) program was used to show the indoor air flow and pollutant concentration distribution. For this purpose, a typical $100m^2$ apartment floor plan was chosen as a case study model and several alternatives were reviewed to improve the IAQ performance. The simulation took place in the condition of natural ventilation through windows.

• Journal of Mechanical Science and Technology
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• v.17 no.7
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• pp.1054-1062
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• 2003

The numerical simulations of flow and pollutant particle dispersion are described for two-dimensional bell shaped hills with various aspect ratios. The Reynolds-averaged incompressible Navier-Stokes equations with low Reynolds number $\kappa$-$\varepsilon$ turbulent model are used to simulate the flowfield. The gradient diffusion equation is used to solve the pollutant dispersion field. The code was validated by comparison of velocity, turbulent kinetic energy, Reynolds shear stress, speed-up ratio, and ground level concentration with experimental and numerical data. Good agreement has been achieved and it has been found that the pollutant dispersion pattern and ground level concentration have been strongly influenced by the hill shape and aspect ratio, as well as the location and height of the source.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.4
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• pp.335-343
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• 2006

Indoor air pollution has been significantly aggravated due to hazardous pollutants emitted from petrochemical finishing materials in new apartments. Pollutants emitted into indoor environment have significant effects on the health of occupants, causing undesirable symptoms related to sick building syndrome such as headache, dizziness, difficulty in concentration, etc. Therefore, this paper attempted to investigate the reduction effect of bake out on VOCs emission in new apartments. Experiments were carried out in three households, one of which was naturally ventilated. The naturally ventilated showed the lowest indoor pollutant concentration and also showed the highest reduction rate by the use of bake out. The most desirable result was observed when the household was naturally ventilated after bake out. More detailed experiments are expected to be carried out afterwards on the prediction of reduction rate of each pollutant.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.107-111
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• 2012

Eight marine sediments from Busan port in Korea were annually analyzed to examine the concentration distribution of dioxins from 2006 to 2010. Yearly mean concentration of dioxins ranged from 186.3 to $383.3pg\;g^{-1}$ in real values and 5.087 to 8.541 pg-TEQ (Toxicity equivalency) based on dry weight of samples. The dioxin concentration at the site near fishing market was the highest concentration among all sampling sites. Also the dioxin concentration at the sites with various pollutant sources such as large ships, sewage influx and thermal power station as well as fishing market was higher than that of the sites without specific pollutant sources. Another main factor that affects the dioxin concentration is topography characteristics of the bay. The bay has relatively high dioxin concentration because of the lack of the pollutant diffusion. This study demonstrated that the dioxin concentration in the site with pollutant sources and the lack of the pollutant diffusion was relatively high as compared with the other sites. As a result of contribution ratio of dioxin congeners, OCDD (Octachlorodibenzodioxin) in all sites was major contributor in real value, in contrast, dioxin congeners in TEQ values were dominated by 2,3,4,7,8-PeCDF.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.2
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• pp.137-145
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• 1997

To predict the effects of air pollutant in the coastal region, we have developed the air pollutant model, the reaction model and the deposition of NO, $NO_2, and O_3$. And the numerical model of air pollutant concentration employed the nested technique to calculate with the higher resolution for the area. The nested technique used two grid systems, one for the large scale calculating region with the coarse mesh grid (CMG) and the other for the small scale region with the fine grid (FMG). In other to prove the validity of the simulation model the calculations were conducted for the present situation. The results of them reasonably agree with the observed data and proved the validity of the model.

• Journal of environmental and Sanitary engineering
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• v.18 no.3 s.49
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• pp.1-10
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• 2003

This study was aimed to investigate the influence on the vicinity by air pollutant generated from facility of the district heating located in local small town. We selected the seven areas arround the surroundings of facility of the district heating, compared the air quality evaluated before and after operations of the facility, and estimated the diffusion of air pollutant exhausted from the facility using a ISC model. The result was that the concentration of TSP before and after operations of the facility was 89${\sim}$94${\mu}$g/m$^3$,and 72${\sim}$81${\mu}$g/m$^3$, respectively and the latter showed a decline in concentration. Also, there was no relationship between straight distance from the facility of the district heating and the concentration of TSP. This result was applicable to cases of PM-10 and SO$_2$. We also investigated the influence on the air around the neighbored area by air pollutant produced from facility of the district heating using ISCLT3 model. The adding-concentrations of TSP, SO$_2$,NO$_2$, and CO were 0.0019${\sim}$0.00183${\mu}$g/m$^3$, 0.0029${\sim}$0.5648ppb, 0.2924${\sim}$l.9837ppb,and 0.0087${\sim}$0.0590ppb, respectively. It is predicted that each concentration is added to pollutant exhausted from facility of the district heating and is about 1/100${\sim}$1/180,000 of present air quality. This has a tiny influence on general air quality. According to this analysis, the concentration of air pollutant is less effected to pollutants expected by the facility of the district heating than other pollutants emitted from mobil source or industrial complex, and etc.

• Journal of Korea Trade
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• v.26 no.3
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• pp.117-136
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• 2022

Purpose - Port is vital for international trade accounting for approximately 80% of world cargo transportation in the global trade sector. Air pollutants emitted owing to the related industry interfaces developed around the port spread throughout the dense population region can have harmful effects on the nearby residents. This study aims to analyze high-concentration diffusion pattern by air pollutants, considering the main management periods by air pollutants. Design/methodology - Employing the concentration criteria per main air pollutant, the analyses of concentration change patterns per air pollutant, wind characteristics that directly affected the air pollutant diffusion, distribution types per air pollutant, and high-concentration diffusion patterns by season according to time changes were conducted. Findings - The substances that caused harmful levels of air pollution in the hinterland living zone of the Busan New Port were PM_10, PM_2.5, and NO_2. Furthermore, the intensive management periods were as follows: For PM_10, 24-h (spring), 12:00-16:00 (summer), 12:00-16:00 (summer), 20:00-12:00 (fall), and 24:00-20:00 (winter), and for PM_2.5, 24-h (all four seasons), and for NO_2, 23:00-04:00 (spring), 23:00-08:00 (summer), and 20:00-08:00 (fall), and 23:00-04:00 (winter). Originality/value - Research finding indicates that regular monitoring and countermeasures to reduce air pollution for each air pollutant makes it possible to achieve effective air quality control in the port and hinterland living zones.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.2
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• pp.169-178
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• 2011

The dispersion of a pollutant in a turbulent boundary layer has been described in this study by using a two-dimensional lattice Boltzmann method (LBM) and the Smagorinsky sub-grid-scale (SGS) model. The scalar transport equation corresponding to the pollutant concentration is adopted; the pollutant is considered to be in a continuous phase. The pollutant source is classified as ground-level source (GLS) and elevated-point source (ES). Air velocity and particle concentration profile for the pollutant are compared with the respective results and profiles obtained in the experiments of Fackrell and Robins (1982) and Raupach and Legg (1983). The numerical results obtained in this study, i.e., the simulation and the experimental data for the mean flow velocity profiles and the pollutant concentration profiles, are in good agreement with each other.

• 수도
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• v.24 no.5 s.86
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• pp.29-44
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• 1997

Sewage sludge produced in Korea was 1,275,800 tons (dewatered sludge cake) per year in 1996, which is 3,495 tons per day, 0.303% of 11,526,100 tons per day of sewage treated in 79 sewage treatment plants. Sludge production has been and will be increasing in accordance with construction of new facilities for sewage treatment. Most of the sludge is currently disposed by landfill and ocean dumping, but it is becoming difficult to find suitable sites for landfill, particularly in big cities such as Seoul. In addition, rapid increase of landfill cost is anticipated in a near future. Current trend for sludge disposal in advanced countries is land application. Over the past 10 to 20 years in the United States, sludge management practices have changed significantly, moving from disposal to beneficial use. They use biosolid for utilization instead of sludge for disposal. Under the Clean Water Act of 1972, amended in 1987 by Congress, the U.S. EPA was required to develop regulations for the use and disposal of sewage sludge. The EPA assessed the potential for pollutants in sewage sludge to affect public health and the environment through a number of different routes of exposure. The Agency also assessed the potential risk to human health through contamination of drinking water sources or surface water when sludge is disposed on land. The Final Rules were signed by the EPA Administrator and were published (Federal Register, 1993). These rules state that sewage sludge shall not be applied to land if the concentration of any pollutant in the sludge exceeds the ceiling concentration. In addition, the cumulative loading rate for each pollutant shall not exceed the cumulative pollutant loading rate nor should the concentration of each pollutant in the sludge exceed the monthly average concentration for the pollutant. The annual pollutant loading rate generally applies to applications of sewage sludge on agricultural lands. The most popular beneficial use of sewage sludge is land application. The sludge has to be stabilized for appling to land. One of the stabilization process for sewage sludge is lime stabilization process. The stabilization process is consisted of the stabilizing process and the drying process. Stabilization reactor can be a drum type reactor in which a crossed mixer is equipped. The additive agents are a very reactive mixture of calcium oxide and others. The stabilized sludge is dried in sun drier or rotary kiln.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.252-254
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• 2003

In this study, it was purposed to develop the new method for the prediction of pollutant concentration in road tunnels. The new method was the use of artificial neural network with the back-propagation algorithm which can model the non-linear system of tunnel environment. This network system was separated into two parts as the visibility and the CO concentration. For this study, data was collected from two highway road tunnels on Yeongdong Expressway. The tunnels have two lanes with one-way direction and adopt the longitudinal ventilation system. The actually measured data from the tunnels was used to develop the neural network system for the prediction of pollutant concentration. The output results from the newly developed neural network system were analysed and compared with the calculated values by PIARC method. Results showed that the prediction accuracy by the neural network system was approximately five times better than the one by PIARC method. ill addition, the system predicted much more accurately at the situation where the drivers have to be stayed for a while in tunnels caused by the low velocity of vehicles.