• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2015년도 제46회 하계학술대회
• /
• pp.1463-1464
• /
• 2015

This paper describes for the diagnosis insulating oil for transformers integrity assessment. The high-capacity oil transformer has several insulators are entered for the purpose of insulation, such as insulating oil, insulating paper and press board. Irradiated with a gas component dissolved in the insulating oil can analyze the status of the transformer, and can prevent a sudden accident in advance.

• Journal of Microbiology and Biotechnology
• /
• 제26권7호
• /
• pp.1320-1332
• /
• 2016

Light hydrocarbons accumulated in subsurface soil by long-term microseepage could favor the anomalous growth of indigenous hydrocarbon-oxidizing microorganisms, which could be crucial indicators of underlying petroleum reservoirs. Here, Illumina MiSeq sequencing of the 16S rRNA gene was conducted to determine the bacterial community structures in soil samples collected from three typical oil and gas fields at different locations in China. Incubation with n-butane at the laboratory scale was performed to confirm the presence of "universal microbes" in light-hydrocarbon microseepage ecosystems. The results indicated significantly higher bacterial diversity in next-to-well samples compared with background samples at two of the three sites, which were notably different to oil-contaminated environments. Variation partitioning analysis showed that the bacterial community structures above the oil and gas fields at the scale of the present study were shaped mainly by environmental parameters, and geographic location was able to explain only 7.05% of the variation independently. The linear discriminant analysis effect size method revealed that the oil and gas fields significantly favored the growth of Mycobacterium, Flavobacterium, and Pseudomonas, as well as other related bacteria. The relative abundance of Mycobacterium and Pseudomonas increased notably after n-butane cultivation, which highlighted their potential as biomarkers of underlying oil deposits. This work contributes to a broader perspective on the bacterial community structures shaped by long-term light-hydrocarbon microseepage and proposes relatively universal indicators, providing an additional resource for the improvement of microbial prospecting of oil and gas.

• 해양환경안전학회:학술대회논문집
• /
• 해양환경안전학회 2006년도 춘계학술발표회
• /
• pp.85-92
• /
• 2006

모든 원유(crude oil) 와 연료유(refined petroleum) 는 서로 구별되는 개별 탄화수소 특성을 가지고 있다. 원유의 경우 산지별로 고유한 특성을 지니고 있으며, 연료유의 경우 같은 유종이라 할지라도 그 원료가 되는 원유의 특성, 또는 생산공정, 생산시기 등에서 차이점이 발생하고 생산시기가 동일한 통일유종의 기름이더라도 선박의 연료탱크 내에 남아있는 잔류물과의 혼합 등에 의해 구별될 수 있는 특징을 가지게 된다. 유지문기법(oil fingerprint method)은 이러한 특성을 이용하여 해상유출유의 오염원을 밝히기 위한 감식 분석기법을 말한다. 현재의 유용한 유지문기법으로는 기체크로마토그래피 (GC)를 이용한 포화탄화수소류 방향족탄화수소류 황화합물 패턴분석방법과 적외선분광광도계(IR)를 이용한 적외선스펙트럼 측정방법 그리고 형광분광광도계(FL)를 이용한 방향족탄화수소류 스펙트럽분석방법 둥이 있으며 GC/MS를 이용한 EICs(Extracted Ion Chromatograms) 패턴분석방법이 있다.

• Corrosion Science and Technology
• /
• 제7권6호
• /
• pp.350-361
• /
• 2008

Canada's oil sands contain one of the largest reserves of oil in the world. According to recent estimates, there are nearly 180 billion barrels of oil in the Canadian oil sands trapped in a complex mixture of sand, water and clay. More than 40 companies have been currently operating or developing oil sands facilities since the first production in 1967. The process of oil sands upgrading is similar with down stream refinery, but the corrosion environment in upgrading refinery is often more severe than in the refinery because of high chlorides, mineral contents, carbonic acid, heavy viscosity and fouling, higher naphthenic acid [$NA-R(CH_{2})nCOOH$], and greater sulfur contents. Naphthenic acid corrosion (NAC) which is one of the most critical corrosion issues in up & downstream refinery plants was observed for the first time in 1920's in refinery distillation processes of Rumania, Azerbaizan (Baku), Venezuela, and California. As a first API report, the 11th annual meeting stated sources and mechanism of NAC in early 1930's. API has been developing the risk base standards, such as API RP580, 571, and Publication 581 which are based on the worst NAC damage in the world since 2000. Nevertheless not only the NAC phenomena and control in Canadian sands oil process are not much widely known but also there are still no engineering guidances for the Canadian sands oil in API standards. This paper will give NAC phenomina and materials selection guidance against NA environment in Canadian oil sands upgrading processes.

• 한국가스학회지
• /
• 제19권1호
• /
• pp.12-17
• /
• 2015

CNG(Compressed Natural Gas)충전소의 주요 핵심설비는 압축기이며, 대부분의 압축기는 윤활이 필요하다. CNG압축기의 윤활유(oil)는 충전 중에 압력 레귤레이터, 엔진 연료공급시스템 등에 전이(Carry-over)되어 천연가스차량의 성능에 부정적인 영향을 미친다. 따라서 이러한 문제를 사전에 방지하기 위해서는 전이되는 오일의 양을 정량적으로 측정하여 공급되는 압축천연가스의 품질관리를 강화하는 것이 필요하다. 본 연구에서는 CNG오일전이를 측정하기 위해 중량법(Gravimetric method)을 사용한 샘플링 튜브 및 샘플링 장비를 개발하였다. 또한, CNG 충전소 6개소를 대상으로 CNG를 채취하였으며, 오일전이를 정량적으로 분석하였다. 측정된 전체 오일전이양은 2.569에서 6.509ppm 이었으며, 측정된 결과를 선행연구 결과와 비교 검증하였다.

• 한국자동차공학회논문집
• /
• 제7권5호
• /
• pp.81-88
• /
• 1999

In order to understand the relationship between the phase angle of piston ring and oil consumption was measured by analyzing $CO_2$concentration in exhaust gas. The use of hydrogen fuel not gasoline makes this possible because all of the carbon component in exhaust gas can be assumed to be produced from oil. As a result of experiment, it is known that the oil consumption varies periodically and a specific location of ring end gap was found at each peak of oil consumption. Therefore, it was found that the oil consumption was not constant even at the same operating conditions and this is because the relative locations of top and 2'nd ring end gap change arbitrarily.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2008년도 동계학술발표대회 논문집
• /
• pp.113-118
• /
• 2008

For a R134a rotary vane compressor used for car air conditioners, characteristics of gas compression and oil supply have been studied. The compressor model under investigation has the low volume ratio of suction to discharge volumes so that there occur flow reversal from discharge port to compression chamber as the leading vane passes over the discharge port. As a result, the volumetric and adiabatic efficiencies turn out to be relatively low compared to other types of displacement compressors. Oil supply mechanism has been comprehended for mathematical modeling and oil flow rate has been calculated for the individual oil passages. This study on the gas compression and oil supply of a rotary vane compressor can be applied to a future design practice on a similar type of compressor.

• Natural Product Sciences
• /
• 제22권1호
• /
• pp.30-34
• /
• 2016

A simple and rapid method based on proton nuclear magnetic resonance spectroscopy was developed for determination of trans-anethole content in fennel essential oil. Spectra of pure trans-anethole, of the pure essential oil of fennel, and of the pure oil of fennel with thymol internal standard were recorded. The signal of $H-1^/$ was used for quantification of trans-anethole. This proton signal is well separated in the proton magnetic resonance spectrum of the compound. No reference compound is needed and cheap internal standard was used. The results obtained from spectroscopic analysis were compared with those obtained by gas chromatography. Additionally, the developed method was used for determination of the type of vegetable oil used as a carrier in commercial products, which cannot be quantified as such by gas chromatography. This study demonstrates the application of proton nuclear magnetic resonance spectroscopy as a quality control method for estimation of essential oil components.

• Tribology and Lubricants
• /
• 제12권4호
• /
• pp.28-34
• /
• 1996

The lubrication characteristics of high-speed ball bearings have been investigated empirically using 45mm bore split inner ring ball bearings employed in small industrial gas turbine engines with oil-jet lubrication method. For the close structural simulation, experiments carried out with bearing mounting supports of real engines, such as bearing housings and oil nozzle assemblies with squeeze film dampers. Thus the results of tests can be directly applied to the design and the development of gas turbine engines. Testing was done by varying operating speeds, axial load on bearings, and lubricant flow rates. During testing, the temperature of bearing at outer-ring face, the power consumption of the driving motor, and the rotating resistance of the bearing were measured. From this study, the representative factors for lubrication characteristics at high speed was found, and the most important one was not operating speed but axial load up to 1.95 million dmN speed and 2969 N axial load. Furthermore, the detailed variation of the rotational resistance of the bearing could be visualized by measuring the change of the radial load under the bearing supports. The rotational resistance consists of the frictional resistance and the bearing-cavity oil resistance.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제21권3호
• /
• pp.14-20
• /
• 2016

Remediation of crude oil contaminated soil is complicate and hard to apply traditional methods because of its persistency, durability, and high viscosity. Therefore, in this study, the efficiency of crude oil contaminated soil remediation was tested by developing a pilot-scale thermal desorption system using the indirect heating method with an exhaust gas treatment. Under optimal condition drawed by temperature and retention time, the remedial efficiency of crude oil contaminated soil and treatability of exhaust gas were analyzed. Total Petroleum Hydrocarbon (TPH) concentration of crude oil contaminated soil was decreased to 69.7 mg/kg on average and the remedial efficiency was measured at 99.60%. Through the exhaust gas, 86.0% of Volatile Organic Compounds (VOC) was degraded and 97.16% of complex malodor was reduced under the suggested optimum operation condition. This study provides important basic data to be useful in scaling up of the indirect thermal desorption system for the remediation of crude oil contaminated soil.