• 한국조경학회지
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• 제33권6호
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• pp.90-97
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• 2006

The effects of a green buffer zone to protect a residential area from air pollution from industrial facilities and traffic was examined by analyzing the case of a green buffer zone in the Shiwha industrial complex. The green buffer zone is 175 m wide. The intent was to assess the dispersion patterns of atmospheric air pollutants and the reduction in concentration around the green buffer zone. To measure atmospheric sulfur dioxide$(SO_2)$ and nitrogen dioxide$(NO_2)$ concentration, badge-type passive samplers were used and set up at 76 locations in order to measure the concentration of air pollutants with respect to the spatial dispersion. The weighted mean values of $SO_2\;and\;NO_2$ concentration were $3\~57 ppb\;and\;18\~62 ppb$ and the differences among the green buffer zone, the industrial area and the residential areas were $0.7\~1.1 ppb$. Mean values of atmospheric concentrations of $NO_2$ were similar in industrial and, residential areas and the green buffer zone. Results of the study show that the effect of the green buffer zone on reducing the dispersion of air pollutants was very low. This study also recommends that micro-climate, i.e., wind direction should be considered as a factor for planning and design of green buffer zones.

• 수도
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• 제24권2호통권83호
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• pp.81-93
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• 1997

• Environmental Engineering Research
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• 제22권1호
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• pp.75-86
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• 2017

The aerosol content dynamics in a virtual system were investigated. The outcome was extended to monitor the mean concentration diffusion of aerosols in a predefined macro and micro scale. The data set used were wind data set from the automatic weather station; satellite data set from Total Ozone Mapping Spectrometer aerosol index and multi-angle imaging spectroradiometer; ground data set from Aerosol robotic network. The maximum speed of the macro scale (West Africa) was less than 4.4 m/s. This low speed enables the pollutants to acquire maximum range of about 15 km. The heterogeneous nature of aerosols layer in the West African atmosphere creates strange transport pattern caused by multiple refractivity. It is believed that the multiple refractive concepts inhibit aerosol optical depth data retrieval. It was also discovered that the build-up of the purported strange transport pattern with time has enormous potential to influence higher degrees of climatic change in the long term. Even when the African Easterly Jet drives the aerosols layer at about 10 m/s, the interacting layers of aerosols are compelled to mitigate its speed to about 4.2 m/s (macro scale level) and boost its speed to 30 m/s on the micro scale level. Mean concentration diffusion of aerosols was higher in the micro scale than the macro scale level. The minimum aerosol content dynamics for non-decaying, logarithmic decay and exponential decay particulates dispersion is given as 4, 1.4 and 0 respectively.

• 상하수도학회지
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• 제31권6호
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• pp.481-490
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• 2017

Water and wastewater treatment has always been a challenging task due to the continuous increase in amount and the change in characteristics of the poorly biodegradable and highly colored organic matters, as well as harmful micro-organisms. Advanced techniques are therefore required to successfully remove these pollutants from water before reuse or discharge to receiving water bodies. Application of ozone, which is a powerful oxidant and disinfectant, alone or as part of advanced oxidation process depends on the complex kinetic reactions and the mass transfer of ozone involved. Micro- and nano bubbling considerably improves gas dissolution compared to conventional bubbles and hence mass transfer. It can also intensify generation of hydroxyl radical due to collapse of the bubbles, which in turn facilitates oxidation reaction under both alkaline as well as acidic conditions. This review gives the overview of application of micro- and nano bubble ozonation for purification of water and wastewater. The drawbacks of previously considered techniques and the application of the hydrodynamic ozonation to synthetic aqueous solutions and various industrial wastewaters are systematically reviewed.

• 한국환경과학회지
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• 제29권11호
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• pp.1025-1032
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• 2020

This work was performed to develop a dip injection wet scrubber (DIWS) system with chlorine dioxide as the oxidant. The exhaust pollutants from a lime kiln of paper-mill were introduced to the system. When NaClO₃ was used to oxidize NO into NO₂, the oxidation was unsatisfactory and the combination of HNO₃ or H₂SO₄ was required for 100% oxidation. ClO₂ is recommended to oxidize NO and SO₂ effectively. With the combination of 1^st stage of DIWS and ClO₂, 57.1% of NOx and 98% of SO₂ were effectively removed. In the case of 2^nd stage of DIWS and ClO₂, 93.5% of NOx and 99% of SO₂ were removed. The ClO₂+DIWS process was superior to the ClO₂+Scrubber process in terms of investment, running cost and NOx removal efficiency.

• 한국지형학회지
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• 제28권1호
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• pp.35-50
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• 2021

In this study, we analyzed the changes in the topographical landscape and the sedimentary environment to evaluate the ecological value of the Dongcheon Estuary and protect the wetland, and presented the conservation management method of the Dongcheon Estuary. Based on the result of topographical landscape analysis, agricultural land tended to decrease continuously, and artificial structures gradually increased. Moreover, in sediment analysis, the Dongcheon Estuary showed both the characteristics of river sediments and coastal sediments, and in some areas problems such as acidification and nutritional imbalance appeared. Therefore, in order to protect and manage the Dongcheon Estuary with high ecological value, it is necessary to limit the development around micro topography and minimize the artificial damage in the Dongcheon Estuary. In addition, efforts such as securing facilities for reducing pollutants and freshwater wetlands for pollutants, that flow in from nonpoint pollutants are required.

• Archives of Pharmacal Research
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• 제4권2호
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• pp.141-153
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• 1981

In Japan, rapid development of economy during the 1960s caused the problems of environmental pollution, and hazards occurred in many places of Japan, water pollution had increased in those days, and water used for drinking, agriculture, fishing, industry nd recreation were demaged. By water-born diseases like as Minamata and Itai-Itai diseases, many patients suffered as you know well. In 1967, Japanese Government set up Basic Law for Environmental Pollution Control and in 1970 Water Pollution Control and in 1970 Water Pollution Control Law.

• 상하수도학회지
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• 제27권6호
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• pp.797-803
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• 2013

Recently, a number of countries are now considering the reuse of effluents from wastewater treatment for various water applications. To improve the reuse of wastewater effluent, the development of appropriate micro-pollutant removal technology is necessary. Although several researche have been studied for removing micro-pollutants in water, little study has been conducted for the removal of emerging contaminant such as antibiotic resistant genes (ARGs) by disinfection processes. Therefore, the aim of this study is to compare the capacity of disinfection technologies such as chlorination, ozone, and electron beam, for removing antibiotic resistant bacteria (ARB) and ARGs. Based on this study, better ARG removal can be achieved by ozonation and electron beam. Relatively, high CT values of chlorination or ozonation are needed to remove ARB and ARG compared to conventional pathogens.

• International Journal of Computer Science & Network Security
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• 제22권6호
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• pp.91-96
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• 2022

The photocatalytic degradation of salicylic acid takes place in several stages involving coupled phenomena, such as the transport of molecules and the chemical reaction. The systems of transport equations and the photocatalytic reaction are numerically solved using COMSOL Mutiphysics (CM) simulation software. CM will make it possible to couple the phenomena of flow, the transport of pollutants (salicylic acid) by convection and diffusion, and the chemical reaction to the catalytic area (bauxite or TiO2 doped by nanoparticles). The simulation of the conversion rate allows to correctly fit the experimental results. The temporal simulation shows that the reaction reaches equilibrium after a transitional stage lasting over one minute. The outcomes of the study highlight the importance of diffusion in the boundary layer and the usefulness of injecting micro-agitation into the microchannel flow. Under such conditions, salicylic acid degrades completely.

• 멤브레인
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• 제27권1호
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• pp.104-107
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• 2017

역삼투막 운영에 있어서 유기물 오염에 대한 문제들을 해결하기 위해 많은 연구를 하고 있다. 현재 가성소다(NaOH)를 사용하여 유기물 오염 제거를 하고 있다. 본 연구는 지속적인 막오염 증가 문제를 해결하기 위한 물리/화학적 세정 기법으로서 기존에 사용하던 가성소다와 Micro-bubble를 이용하여 유기물 오염 제거 실험을 수행되었다. 멤브레인 강제 오염을 위해 Humic acid sodium, Bovine serum albumin, Sodium alginate 약품을 사용하여 유기물 오염을 시켰다. 유기물 오염에 따른 Flux를 관찰하였고, 가성소다와 Micro-bubble를 이용한 유기물 오염 제거 실험은 가성소다로만 사용했을 때보다 향상된 것을 관찰했다.