• Journal of Electrical Engineering and Technology
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• 제12권1호
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• pp.486-493
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• 2017

Refineries and chemical plants with isolated power systems that have a limited power supply are more susceptible to voltage changes from disturbances compared to power systems connected with a power company. Furthermore, most loads in such cases are induction motor loads, and therefore, transient voltage characteristics when starting a high-capacity motor must be examined. In general, high-capacity motors are customized appropriately to the load performance curve by the manufacturer during the construction of an industrial plant. Subsequently, when complying with the voltage drop permitted by international standards during the design process, power supply equipment such as transformers and generators is overdesigned. Therefore, a novel analysis is necessary on standards for startup and constraint voltage drops, as well as on identifying the voltage drop limitations for starting high-capacity motors in refineries and chemical plants with isolated power systems. In this study, field tests on an industrial plant were conducted, and simulations modeled under conditions identical to those of the field test system were performed using the general-purpose program ETAP in order to compare the results.

• 환경영향평가
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• 제19권3호
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• pp.259-270
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• 2010

We conducted human risk assessment for exposure to inhalation of chemical substances emitted from the storage tanks of petroleum refineries. To assess human risk, this study calculated chemical emissions from the external floating roofs on storage tank at petroleum refineries, as well as concentrations thereof in the ambient air using the K-SCREEN model, and then determined risk in accordance with the Reference Concentration (RfC) values and Inhalation Unit Risk criteria developed by the US Environmental Protection Agency. The results indicated that non-carcinogenic chemicals have a hazard quotient of less than 1, meaning they have an insignificant effect on human health for residential areas near the storage tanks. Among the known carcinogens, the hazard risk for benzene slightly exceeded $10^{-6}$, indicating the need for corrective reduction measures. The methodology for health impact assessment devised herein provides findings useful in decision making for policy makers and the general public with respect to construction of industrial complexes. However, the methodology proposed herein does have limitations, including discrepancy in results induced by use of U.S. data (due to the lack of usable domestic data). More systematic studies from related researchers will be needed to address these issues and produce more reliable outcomes.

• 한국항해항만학회지
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• 제27권3호
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• pp.289-295
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• 2003

The international oil majors have been reducing the size of their own oil tanker fleet since early 1980s. Like international oil majors, the Korean refineries are becoming more dependent on tanker chartering rather than tanker ownership for their oil transportation since the 1990s. They also prefer spot charter to time charter and this kind of trend has continued up to now. Consequently, this paper attempted to find the factors influencing changes in tanker fleet composition. To attain the object of the paper, an empirical study is adopted using the ten decision-making factors derived from preceeding studies. The findings are that MARPOL and OPA 90, and transportation costs are the most important factors influencing an oil tanker fleet composition.

• 방재기술
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• 통권12호
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• pp.21-30
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• 1992

This fire fighting systems engineering specification includes the design and installation requirements which normally adopted for petroleum refineries and petrochemical industries. Also, this shall be applied the Korean Fire Safety Law, in addition to the Korean Industry Safety & Health Law and NFPA Code.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.447-459
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• 2010

Bacterial diversity of two distinct wastewater treatment systems, conventional activated sludge (CAS) and membrane bioreactor (MBR), of petroleum refineries were investigated through 16S rRNA gene libraries. Sequencing and phylogenetic analysis showed that the bacterial community composition of sludge samples was distinct between the two wastewater treatment systems. MBR clones belonged predominantly to Class Betaproteobacteria, represented mainly by genera Thiobacillus and Thauera, whereas CAS clones were mostly related to Class Alphaproteobacteria, represented by uncultured bacteria related to Order Parvularculales. Richness estimators ACE and Chao revealed that the diversity observed in both libraries at the species level is an underestimate of the total bacterial diversity present in the environment and further sampling would yield an increased observed diversity. Shannon and Simpson diversity indices were different between the libraries and revealed greater bacterial diversity for the MBR library, considering an evolutionary distance of 0.03. LIBSHUFF analyses revealed that MBR and CAS communities were significantly different at the 95% confidence level ($P{\leq}0.05$) for distances $0{\leq}D{\leq}0.20$. This work described, qualitatively and quantitatively, the structure of bacterial communities in industrial-scale MBR and CAS processes of the wastewater treatment system from petroleum refineries and demonstrated clearly differentiated communities responsible for the stable performance of wastewater treatment plants.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2003년도 춘계공동학술대회논문집
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• pp.257-264
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• 2003

우리나라 정유회사는 1980년대부터 오일운송을 소유 오일탱커보다도 용선에 의존하는 비율이 높아지고 있으며, 용선중에서도 정기용선보다는 스팟(spot)용선을 선호하고 있다. 그러면 국내 정유회사가 어민 의사결정요인에 의하여 자사 소유 탱커선보다도 용선에 의존하여 오일운송을 하는지, 혹은 전적으로 용선에만 의존하여 오일운송을 하는지를 규명하고자 하는 것이 본 연구의 목적이다. 따라서 연구의 목적을 달성하기 위하여 선행연구에서 3가지 절차, 즉 선행연구, 설문조사 그리고 전문가 의견조사를 거쳐 도출된 10개의 의사결정요인을 활용하여 본 논문에서는 어떠한 요인들이 정유사의 선대구성에 영향을 미쳤는지를 설문과 면접법에 의하여 실증분석하였다. 연구 대상인 국내 정유회사는 모집단인 현대 및 인천정유, LG-Caltex, S-oil 그리고 SK 등 4개이며 분석의 초점은 각 요인이 정유회사의 탱커선대의 구성에 미치는 영향 즉, 탱커 소유와 용선의 증감 추이와 용선형태의 변화에 두었다. 분석결과 운송비용상승요인과 국제규정인 MARPOL과 OPA 90요인이 탱크선대구성에 가장 큰 영향을 미치고 있었다.

• 자원ㆍ환경경제연구
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• 제24권2호
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• pp.311-342
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• 2015

본 논문에서는 경제이론과 실증분석을 통하여 이명박 정부가 석유제품 시장에 개입한 논거를 평가하였다. 한국을 포함하여 세계적으로 정제산업은 과점이 보편적이며, 역차별적인 수준의 대외 시장개방에도 불구하고 석유제품 시장에서 국내 정유4사의 시장점유율이 높게 지속되는 이유는 정유4사가 국제적인 가격경쟁력을 보유하고 있고 MOPS 가격을 기준으로 경쟁적인 가격책정을 하고 있기 때문이다. 국내 세전 소비자가격은 일본의 가격과 '27개 EU권 국가의 가격들을 가중평균한 값'보다 통계적으로 유의하게 현저히 낮았다. 한국, 일본, 14개 EU권 국가들을 대상으로 가격 비대칭성의 존재여부와 상세내역을 분석한 결과, 휘발유의 경우 한국과 11개 EU권 국가, 경유의 경우 한국과 8개 EU권 국가에서 비대칭성이 있는 것으로 판별되었다. 가격 비대칭성은 다양한 경제 경영적 원인에 의해 다양한 제품과 시장구조에서 발생한다. 소비자 복지의 관점에서는 한국의 세전 소비자가격이 현저히 낮다는 점이 제일 중요하다.

• 분석과학
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• 제11권6호
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• pp.469-473
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• 1998

자동차용 휘발유 제조사의 확인 또는 판별은 석유류의 정상적인 유통관리 및 오염사고시 오염원의 추적을 위해 필요하다. 일반적으로 휘발유의 화학적 조성은 가스크로마토그래피(GC)로 분석이 가능하며, 제품별로 얻어진 크로마토그램의 차이로부터 각 제품을 구분할 수 있으나 제조기준의 세분화로 휘발유의 조성이 유사해져 GC분석에 의한 판별이 더욱 어렵게 되었다. 본 연구에서는 보다 신속하고 정확하게 휘발유 제품을 판별하기 위하여, 분산제의 적외선 분광스펙트라를 비교하여 제조사(A, B, C, D, E사로 구분)를 구분하는 방법을 도식화하였다. IR spectra는 휘발유를 검시험기(gum tester)로 증발시키고, 잔여물을 n-pentane으로 녹여 ATR(Attenuated Total Reflectance) cell로 옮기고 다시 용매를 증발시킨 후에 얻었다. 'A', 'B', 및 'C'정유사에서 사용하는 첨가제들은 에테르(ether)의 C-O 신축진동에 의한 넓고 강한 피크가 $1,096cm^{-1}$에서 나타나 'D'와 'E'정유사의 첨가제들과 뚜렷하게 구별이 가능하였고, 또 다른 특징적인 피크들로써 각 정유사 제품의 구분이 모두 가능하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2002년도 춘계학술대회논문집
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• pp.73-87
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• 2002

• Interaction and multiscale mechanics
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• 제5권3호
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• pp.211-228
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• 2012

This paper reports the development of a generalized inverse analysis formulation for the parameter estimation of four-parameter Burger model. The analysis is carried out by formulating the problem as a mathematical programming formulation in terms of identification of the design vector, the objective function and the design constraints. Thereafter, the formulated constrained nonlinear multivariable problem is solved with the aid of fmincon: an in-built constrained optimization solver module available in MatLab. In order to gain experience, a synthetic case-study is considered wherein key issues such as the determination and setting up of variable bounds, global optimality of the solution and minimum number of data-points required for prediction of parameters is addressed. The results reveal that the developed technique is quite efficient in predicting the model parameters. The best result is obtained when the design variables are subjected to a lower bound without any upper bound. Global optimality of the solution is achieved using the developed technique. A minimum of 4-5 randomly selected data-points are required to achieve the optimal solution. The above technique has also been adopted for real-time settlement of four oil refineries with encouraging results.