• 한국입자에어로졸학회지
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• 제18권4호
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• pp.97-107
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• 2022

The geometry of popular wave plate type mist eliminator for the wet flue gas desulfurization process was improved, fabricated, and experimentally evaluated. A Mist eliminator is a type of inertial particle collector which collection efficiency is proportional to the velocity of the gas phase. However, as the amount of re-entrainment is also proportional to the gas phase velocity, there is a limitation for the gas phase flow rate. Re-entrainment is one of the most important issues in a mist eliminator and is likely to occur as the input of the liquid phase and flow rate of the gas phase increase. In order to resolve this problem, the projection angle of the improved mist eliminator is set to 30° from the conventional one while maintaining the cross-section. With low flow rate conditions, the modified mist eliminator showed a similar pressure drop and overall collection efficiency. However, with conditions in which re-entrainment is obviously occurring, the modified mist eliminator showed better performance in draining droplets than the conventional one. As a result, the modified mist eliminator showed higher overall collection efficiency.

• 한국입자에어로졸학회지
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• 제14권3호
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• pp.73-80
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• 2018

Recently, there has been much research on the effect of ultrafine dust on human body with increasing interest in the ultrafine dust. In the Republic of Korea, there are many old thermal power plants, and the amount of ultrafine dust emitted from the thermal power plants is reported to be about 14% of the total amount of domestic fine dust. Therefore, the amount of fine dust from the flue gas desulfurization facility in the thermal power plant needs be reduced. In this study, we made an experimental setup to simulate a flue gas desulfurization facility and analyzed the physical characteristics of the particles passing through a mist eliminator. Experiments were carried out to investigate the collection efficiency of the mist eliminator by using the Arizona Test Dust in a dry environment, and then spraying limestone slurry into the flue gas desulfurization system equipped with the mist eliminator to examine the size and morphology of limestone particles upstream and downstream of the mist eliminator. Cut-off size of the mist eliminator was formed at about $6{\mu}m$. The result of this study is expected to be helpful for designing an electrostatic precipitator for removing particles passing through the mist eliminator.

• 한국안전학회지
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• 제29권6호
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• pp.49-54
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• 2014

Electrostatic eliminators are essential in various areas of manufacturing industries to protect electrostatic hazards and to reduce inferior products. For ion sources used in the charge neutralizers, there are corona discharge, soft X-ray, and ultraviolet and glow discharge. Among them, corona discharge is generally used, because the corona discharge can easily and economically produce positive and negative ions including electrons in air at atmospheric pressure. But it is necessary to equip explosion-protection electrostatic eliminators wherever hazardous atmosphere. The electrostatic eliminators and their testing method of explosion-protection type have been developed in this research. The contents and scope of the research as follows; developing the type 'Ex s IIB T4' electrostatic eliminator of explosion-protection; developing the type 'Ex s d IIB T4' electrostatic eliminator of explosion-protection; developing the explosion-protection performance testing method of electrostatic eliminator for using AC power source.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 추계학술논문집 1부
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• pp.370-372
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• 2011

Mist Eliminator(ME)는 화학 공정플랜트 요소부품으로 석유화학공정에서 vapor stream에 존재하는 미세액적의 제거를 위해 많이 사용된다. 하지만 mist eliminator의 설계를 위한 기술접근이 어려워 국내 기술수준은 아주 낮은 상태이다. 본 연구에서는 CFD 소프트웨어를 이용하여 단일 재질(stainless)로 구성된 mist eliminator의 밀도 및 크기 변화에 따른 유동장 내부의 압력, 유속, 유선결과의 예측하였으며, 동일하게 설계된 실험값을 이용하여 Souders-Brown 계수 K를 예측하였다.

• 한국입자에어로졸학회지
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• 제12권4호
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• pp.135-143
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• 2016

Removal of water contents in a gas is needed in industrial field of gas processing related on energy production/conversion, and environmental treatment. Inertial separators are economic devices for separating droplets from the gas stream. For accurate understanding of removal process in a curved vane mist eliminator, a numerical model including turbulent dispersion, evaporation and condensation of water vapor at surface of droplets is required. A two-stage curved vane mist eliminator has been modeled, and fluid flow of mixture of air and water vapor and droplet trajectories were solved simultaneously with taking into account two-way coupling. Removal efficiency of droplets with various inlet condition of relative humidities (RH, 40%, 90%, and 100%) were compared. As RH increased, the effect of evaporation decreased and inertial separation efficiencies of droplets obtained increased especially for droplets of diameter below 10 micrometers.

• 한국안전학회지
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• 제24권6호
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• pp.50-54
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• 2009

Ionizer is used for improving manufacturing process and reducing inferior goods in the clean room. As a general rule, neutralization of the electrostatic charge is most important to make TFT-LCD, PDP and OLED. Pulse AC-static eliminator with output voltage of about 10.5kV has been used these days as neutralization device. But this device has a problem with lower performance which was caused by particles-adhesion on the electrode when it has been used for a long time. So we studied to solve the problem with lower performance using high Frequency(72kHz) static eliminator which was produced by Piezo transformer device, and compared Pulse-AC type with Piezo-electronic device such as decay time and ion balance for 10 weeks periods. As a result of this study, we found that Piezo transformer device has been maintained normal condition for 10 weeks. Also, we made the rule by this study, normally Piezo transformer device has to clean the electrode during every 11th weeks.

• KIEE International Transactions on Electrophysics and Applications
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• 제5C권6호
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• pp.228-232
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• 2005

The effects of the pressure and temperature of airflow were experimentally investigated to improve the performance of a nozzle-type electrostatic eliminator. The pressure ($A_P$) and the temperature ($A_T$) of the airflow toward the needle electrode were controlled in the ranges of 0 Mpa to 0.3 Mpa and of $25^{\circ}C$ to $125^{\circ}C$, respectively. It was confirmed that the ion-generation ability was increased depending on the magnitude of the $A_P$ and the $A_T$ of the airflow provided to the surrounding region of the needle electrode in the nozzle-type electrostatic eliminator. In addition, it was clear that the mixed effect of the $A_P$ and the $A_T$ of the airflow was large. These results were attributed mainly to (1) the activation of the corona discharge by the $A_T$, (2) the change of the decomposition and production of a suppression gas by the $A_T$, (3) the blow-off of the suppression gas near the needle electrode by the $A_P$, and (4) the change of the distribution of the current densities on the needle electrode by the $A_P$.

• 한국입자에어로졸학회지
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• 제15권2호
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• pp.57-65
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• 2019

Recently, there has been much research on the effect of fine dust on human body with increasing interest in the fine dust. Thermal power plant, which is considered as one of the main sources of fine dust, is reported to be responsible for 14% of the total amount of domestic fine dust in the Republic of Korea. Therefore, dust collecting devices in the thermal power plant need to be improved. In this study, the electrostatic precipitator (ESP) was considered to substitute for a mist eliminator used in flue gas desulfurization facility. By considering real situation in the flue gas desulfurization facility, the collection efficiency of the ESP was evaluated by using the sprayed limestone slurry particles. The collection efficiency of the ESP was higher than that of the mist eliminator, showing the possibility of replacing the mist eliminator with the ESP in flue gas desulfurization facility.

• 한국화재소방학회논문지
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• 제18권4호
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• pp.22-26
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• 2004

정전기 방전에 의하여 주위의 가연성 가스에 폭발을 일으킬 수 있는 가스관련시설, 석유화 학 공장, 화약공장, 필름생산공장, 반도체 공장 등과 같은 가연성 가스를 주로 취급하는 장소에서는 정전기를 제거하기 위해 제전기를 사용하고 있다. 본 연구에서는 이들 장소에서 주로 사용되고 있는 전압인가식제전기(static eliminator)의 Bar에서 발생하는 방전에 의한 가연성 가스의 폭발현상을 고찰하였다. 가연성 가스는 수소, 에틸렌, 프로판, 메탄 가스 등을 사용하였으며, 제전기의 이온발생 Bar의 길이, 이온발생 전극의 수 및 이온발생 전극에 인가되는 전압의 변화에 따른 점화 현상을 연구하였다. 연구결과 Bar의 길이가 짧을수록 폭발의 위험성이 증가됨을 확인할 수 있었으며 또한 900㎜이상의 Bar에서 전극의 수가 1개인 경우 일반적으로 사용하는 가연성 가스에서는 점화가 되지 않음을 알 수 있었다.

• 한국안전학회지
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• 제21권3호
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• pp.22-30
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• 2006

On this study, we developed the electrostatic eliminator for charged particles in manufacturing process. The characteristics of the electrostatic eliminator were investigated, which is two kinds. The first one is Electrical Corona Discharged Type Ionizer. The second one is Photo Ionizer in using soft X-ray. From the experiment, we have obtained the following results. In case of Electrical Corona Discharged Ionizer, neutralization efficiency of charged particles were approximately saturated to 98% over 6.0kV, but as it is non-explosion proof, can not be used in flammable particle treatment process. While in case of photo Ionizer in using soft X-Ray, neutralization efficiency of charged particles were approximately 95%, and more its structure is explosion proof, could be used in flammable particle treatment process.