• Journal of the Korea Institute of Building Construction
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• v.18 no.4
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• pp.337-345
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• 2018

In this study, observations of oil leakage samples taken from the actual site were performed to identify the causes of the oil leakage phenomenon. As a result, the separation of the material components was determined as the main cause of the oil leakage phenomenon based on the changes in the surface conditions, and verification of this was conducted. The evaluation results confirmed that the filler component of the asphalt mastic subsided with the lapse of the settling time, and that the difference ratio of the filler contents of the upper and lower specimens was up to 23.8% after day 28. Based on these results, a hypothesis on the oil leakage mechanism of asphalt mastic was established, and then modeling of the entire process of oil leakage was performed.

• Journal of the Korea Institute of Building Construction
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• v.21 no.1
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• pp.51-59
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• 2021

In this study, the purpose of this study was to quantitatively grasp the specific correlation between the raw material and the occurrence of leakage by analyzing the characteristics of leakage by adjusting the type and content of the raw material constituting the asphalt mastic coating waterproofing material. To this end, two raw materials, CA (calcium carbonate) and ASE (anti-sedimentation), which are organic and mineral extender for asphalt mastic waterproofing membrane coating, were selected. viscosity and oil leakage stability (20 ℃, 40 ℃) was evaluated. As a result of the evaluation, the oil leakage stability and viscosity were inversely proportional to the CA average particle size, and it was quantitatively proven that a correlation in proportion to the ASE content was established. The results of this study are expected to be used as core data for basic mixing design in the future mixing studies to improve leakage of asphalt mastic waterproofing membrane coating.

• Journal of Ocean Engineering and Technology
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• v.11 no.4
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• pp.189-196
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• 1997

An oil tracking system that monitors the spilt oil trajectory by using GPS was developed. The system consists of a tracking buoy deployed on the oil spilt area and an onshore(or onboard) monitoring station. The tracking buoy is equipped with GPS, signal converter, handy radio and battery while the monitoring station includes a station radio, signal converter, antennas and PC. The hull shape of buoy is designed to effectively simulate the spilt oil movement at sea surface. Radio sets for HAM are used as a data transmitter and a data receiving station, and signal converter is also for amateur use. A field experiment was conducted and it was shown that the integrated system is relable and robust. The developed oil tracking system reveals reatively good performance at reasonable cost. In favorable environment the system may communicate in the distance more than 50km.

• Journal of the Korean Society for Marine Environment & Energy
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• v.1 no.2
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• pp.40-51
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• 1998

The interaction of contained oil slicks with current was investigated with a two-dimensional experimental setup in the circulating water channel facility. A vertical plate was used to contain the oils against the currents and the evolution of the oil slick, mainly focusing on the water/oil interface, was examined with an aid of a laser sheet. Two different oils - soy bean oil and diesel oil - were studied with varying the current speed (10 cm/sec to 35 cm/sec), the barrier depth (4 cm and 8 cm) and the volume of oil (2 liter to 12 liter). Different types of the interface behavior were observed according to the conditions and their mechanism was discussed based basically on the dimensional analysis. The critical speeds of two types of oil loss mechanism (entrainment failure and drainage failure) were also examined.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.568-569
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• 2019

20~30년 전부터 국내 지중송전선로에 OF(Oil Filled)케이블을 사용해 왔다. OF케이블은 오랜 시간동안 신뢰성을 화고하고 있으며, 전연파괴 사고를 미연에 방지할 수 있는 장점이 있지만 유지보수에 많은 어려움이 있고, 절연유에 의한 환경오염이 발생하며, 화재에 취약한 단점이 있다. 최근 20~30년 전에 설치된 OF케이블의 수명이 한계에 도달하면서 고장 위험성이 증가하고, 누유의 위험성이 도사리고 있다. 본 논문에서는 OF케이블 상태 진단방법에 있어서 절연유에 반응하는 필름센서를 활용하여 절연유 탱크의 연결부에서 누유현상을 감지하여 OF케이블 누유 관리시스템을 개발하자 한다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1399-1406
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• 2011

The reducer of the mixer is one of the main parts of the processor used for water and wastewater treatment. In this study, an advanced reducer with a drywell structure was developed in order to prevent oil leakage during operation in the field. During the development of the advanced reducer prototype, a mockup, a metal mold, and a cast were made using CAD and a CNC machine. The structural safety of the reducer prototype's lower housing (drywell structure) was checked using the ALGOR commercial FEM analysis code, which yielded a von Mises stress of about 123 N/mm2, which is below the yield stress of 250 N/$mm^2$, and a natural frequency of about 650-700 Hz. In addition, the torque transmission efficiency for the advanced prototype was 95.87%, which is about 8% more than that found in a previous study, 88.45%, and the sound level was below 75 dB. Furthermore, no oil leakage or abnormal sound or vibration occurred. Therefore, an optimally designed advanced reducer prototype has been successfully developed.

• Journal of Soil and Groundwater Environment
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• v.9 no.4
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• pp.62-73
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• 2004

The current status and problems of UST management in gas stations were reviewed, and suggestions were made for possible improvement of UST management. Regulations and programs relevant through the whole life cycle of the UST, such as construction, installation, operation, and disclosure are insufficient to prevent oil release. The UST requirements are less stringent compared to those of the U.S. and EU members. Current soil test does not seem to be practically effective in detecting soil contamination caused by oil release. The potential for subsurface contamination due to oil release from the UST is estimated from available data other than soil test results. Much higher following future directions and suggestions are made to improve current unsatisfactory UST management: Firstly, increasing the UST requirements - establishing more stringent standards for new UST facilities, and adding new regulatory requirements for existing UST facilities; secondly, replacing current soil test with the tank and piping tests; thirdly, reinforcing programs for supervising the tank construction and installation; fourthly, constructing a system in which independent gas stations can properly manage the USTs; and lastly, educating UST owners and operators, and constructing DB of UST facilities.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.162-163
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• 2002

기름의 하역 및 선적작업이 이루어지는 유조선의 입ㆍ출항이 빈번한 정유시설 인접항은 누유사고의 위험성이 매우 크므로 사고에 대비한 효과적인 방제장비의 확보가 절실히 요구된다. 또한 이러한 유출사고는 어민의 경제활동에 영향을 미치어 그들의 생계를 위협할 수 있으므로 유출기름은 신속하게 방제되어야 한다. (중략)

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.12
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• pp.1702-1714
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• 1998

Removal of spilled oil over the sea and the river has become one of the urgent problems in these days. Removing oil using mechanical devices was recommended because chemical dispersion could cause the secondary contamination in the environment. In the present study a series of experiments were carried out to study the effect of operating conditions, especially, the angle between the belt and the fluid surface on the rate of recovery for the spilled oil using a belt skimmer. Three different types of operation, namely, upward pickup, downward pickup and up-and-downward pickup situations have been investigated for various contact angles, belt speeds and oil thicknesses to find the effects on the recovery rate. The highest rate of oil recovery was found in the case of a contact angle of $45^{\circ}$ and downward pickup. Furthermore, an optimal belt speed was found to reach the saturated recovery rate for a given oil thickness.

• Journal of Navigation and Port Research
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• v.27 no.2
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• pp.239-246
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• 2003

When oil is spilled at sea, the oil boom is commonly used to tackle the movement and spreading of oil in an early stage of oil spill combat. But the retaining capability of oil boom is affected by various factors, such as water velocity, viscosity and density of oil, water depth, oil volume and the length of boom draft. In this study, a computer modelling was peformed to investigate how these factors influence the oil retaining process. The Fluent, most popular one of many CFD(computational fluid dynamics) programs is chosen for modelling and modelling results were verified using the empirical data. It is expected that results of this study will be useful data for oil boom designer and oil spill response commander.