• International Journal of Naval Architecture and Ocean Engineering
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• 제2권3호
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• pp.155-170
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• 2010

Availability of economic and efficient energy resources is crucial to a nation's development. Because of their low cost and advancement in drilling and exploration technologies, oil and gas based energy systems are the most widely used energy source throughout the world. The inexpensive oil and gas based energy systems are used for everything, i.e., from transportation of goods and people to the harvesting of crops for food. As the energy demand continues to rise, there is strong need for inexpensive energy solutions. An offshore platform is a large structure that is used to house workers and machinery needed to drill wells in the ocean bed, extract oil and/or natural gas, process the produced fluids, and ship or pipe them to shore. Depending on the circumstances, the offshore platform can be fixed (to the ocean floor) or can consist of an artificial island or can float. Semi-submersibles are used for various purposes in offshore and marine engineering, e.g. crane vessels, drilling vessels, tourist vessels, production platforms and accommodation facilities, etc. The challenges of deepwater drilling have further motivated the researchers to design optimum choices for semi-submersibles for a chosen operating depth. In our series of eight papers, we discuss the design and production aspects of all the types of offshore platforms. In the present part I, we present an introduction and critical analysis of semi-submersibles.

• 자원환경지질
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• 제44권2호
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• pp.153-159
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• 2011

본 연구에서는 포괄적 역학모델을 이용하여 석유 생산 시스템의 파이프 내 가스-오일 2상유동에 대한 유동패턴을 결정하였다. 2상의 유체는 운영 인자, 기하학적 변수, 유체 물성 등에 따라 특정의 유동패턴을 나타냈다. 광범위한 기액 겉보기 속도에 대하여 시스템의 인자들을 변화시키면서 유동패턴을 비교하였다. 다양한 인자들 중 경사각과 겉보기 속도가 파이프 내 가스-오일 2상유동의 유용패턴을 결정하는데 가장 지배적인 인자로 나타났다. 파이프 직경, 유체 물성 등의 인자들은 전이 경계선 부근을 제외하면 유동패턴 변화에 제한적인 영향 만을 미쳤다. 역학모델은 실험실 평가나 신뢰성있는 상관식 이용이 불가능할 때 유동패턴을 결정할 수 있는 유용한 도구이다.

• 한국유체기계학회 논문집
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• 제16권1호
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• pp.56-60
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• 2013

Non-conventional oil resources such as shale gas are becoming increasingly important and have drawn the attention of several major oil companies all over the world. Nevertheless, the market-changing growth of shale gas production in recent years has resulted in the emergence of environmental and water management challenges. This is because the water used in the hydraulic fracturing process contains large amount of pollutants including ions, organics, and particles. Accordingly, the treatment of this flowback water from shale gas plant is regarded as one of the key technologies. In this study, we examined the feasibility of membrane distillation as a treatment technology for the water from shale gas plants. Direct contact membrane distillation (DCMD) is a thermally-driven process based on a vaper pressure gradient across a hydrophobic membrane, allowing the treatment of feed waters containing high concentration of ions. Experiments were carried out put in the lab-scale under various conditions such as membrane types, temperature difference, flow rate and so on. Synthetic feed water was prepared and used based on the data from literature. The results indicated that DCMD is suitable for treating not only low-range flowback water but also high-range flowback water. Based on the theoretical calculation, DCMD could have over 80% of recovery. Nevertheless, organic pollutants such as oil and surfactant were identified as serious barriers for the application of MD. Further works will be required to develop the optimum pretreatment for this MD process.

• Journal of Microbiology and Biotechnology
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• 제27권5호
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• pp.990-994
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• 2017

Polyhydroxyalkanoates (PHAs) are biodegradable plastics produced by bacteria, but their use in diverse applications is prohibited by high production costs. To reduce these costs, the conversion by Pseudomonas strains of PHAs from crude sludge palm oil (SPO) as an inexpensive renewable raw material was tested. Pseudomonas putida S12 was found to produce the highest yield (~41%) of elastomeric medium-chain-length (MCL)-PHAs from SPO. The MCL-PHA characteristics were analyzed by gas-chromatography/mass spectrometry, gel permeation chromatography, and differential scanning calorimetry. These findings may contribute to more widespread use of PHAs by reducing PHA production costs.

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2005년도 추계정기총회 및 제26회 학술발표대회 고분자리싸이클링기술 특별심포지엄
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• pp.47-58
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• 2005

온도변화에 따른 볏짚의 열분해 생성물의 분포와 생성물의 화학적 구성을 알아보기 위하여 볏짚의 열분해 실험을 진행하였다. 열분해 온도는 약 466, 504, $579^{\circ}C$사이에서 진행하였다. 유동화 가스로는 생성가스를 사용하였으며 유량은 30L/min을 사용하였다. 볏짚의 열분해 결과 기체, 액체, 고체 물질을 얻을 수 있었다. 기체물질은 GC(TCD, FID)를 이용하여 성분 조성을 분석하였다. 액체물질은 상등액과 tar로 분리하여 발열량, 원소분석, 수분, GC/MS를 통해 화학구성성분을 분석하였다. 고체물질은 원소분석, 발열량을 측정하였다. 액체물질의 화학특성 분석결과 연료뿐만 아니라 화학 원료물질로서의 사용가능성을 볼 수 있었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.717-720
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• 2011

석유자원 고갈, 높은 원유가격 문제 그리고 온실가스인 $CO_2$ 에 의한 지구온난화 문제 때문에 바이오 매스를 이용한 GTL(Gas To Liquid) 공정으로 제조하는 청정 합성연료에 대한 관심이 크게 증가하고 있다. 본 논문에서는 GTL 기술의 3가지 핵심인 천연가스 개질반응, 피셔-트롭스 합성 그리고 물성조절 공정에 관한 기술을 설명하고 각국의 개발현황을 비교하였다.

• 한국세라믹학회지
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• 제49권6호
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• pp.561-565
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• 2012

Due to their unique combination of properties, Si-based ceramics, such as silicon carbide (SiC), silicon nitride ($Si_3N_4$) and silicon oxide ($SiO_2$ as fused silica), have a range of industrial applications in fields such as the chemical industry, aluminum manufacturing, oil and gas production and solar cell production. For each materials group, examples of typical applications from various industry sectors are presented while taking into account the property fingerprint.

• 융복합기술연구소 논문집
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• 제11권1호
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• pp.13-18
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• 2021

It is widely accepted that the prevention of global warming requires significant reductions in greenhouse gases, particularly CO₂ emissions. Although fossil fuel-based power plants account for the majority of CO₂ emissions, it is urgent to reduce CO₂ emissions in industries that emit large amounts of CO₂ such as steel, petrochemical, and oil refining. This paper examines the current status of CO₂ emission in the domestic oil refining industry and CO₂ emission sources in each unit process in the oil refining industry. Focusing on the previously developed CO₂ capture process, cases and applicability of greenhouse gas reduction in FCC and hydrogen manufacturing processes, which are major processes constituting the oil refining industry, are reviewed.

• Journal of Advanced Marine Engineering and Technology
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• 제39권6호
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• pp.662-669
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• 2015

해저 석유생산시스템에서 빈번히 발생하는 왁스집적 문제는 안정적인 석유 생산을 방해하고 높은 비용을 발생시키므로 왁스집적 제어에 대한 관심이 증가하고 있다. 왁스집적 제어를 통한 석유의 유동안정성 확보를 위해서는 왁스집적거동을 신뢰성 있게 예측해야 한다. 이 연구에서는 왁스집적 거동에 큰 영향을 미치는 분자확산, 전단응력효과, 왁스경화 메커니즘을 시뮬레이션 기술에 적용하여 불확실도가 높은 변수인 전단응력계수, 왁스고형물의 공극률, 왁스 열전도도, 분자확산계수와 물과 가스 양이 왁스집적 거동에 미치는 영향에 대한 분석을 단상과 다상 유동 시 층류 유동 조건에서 수행하였다. 그 결과 왁스고형물의 공극률과 분자확산계수가 높아질수록, 전단응력계수가 낮아질수록 왁스집적 두께가 두꺼워지는 것을 확인할 수 있었고 석유의 온도가 왁스집적 위치에 주요하게 영향을 미치는 것으로 판단된다. 물의 양에 따른 왁스집적 시뮬레이션 결과 기존 연구에서 다소 다른 결과들이 존재하나 이 연구 조건에서는 물의 양 40%까지 왁스집적량이 증가하다 감소하는 것을 확인하였고 가스 양이 많아질수록 유체의 액상 내 가벼운 탄화수소 농도 감소로 인해 왁스집적량이 증가하는 것을 파악하였다. 이 연구결과는 향후 현장 또는 현장을 모사한 실험시스템에서의 결과와 시뮬레이션 결과를 매칭하여 해저 유동관에서 왁스집적 거동을 예측하는데 효과적으로 적용될 수 있을 것으로 사료된다.

• 한국입자에어로졸학회지
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• 제13권3호
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• pp.119-125
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• 2017

A novel two stage cylindrical cyclone was developed for a 3 phase separator in shale oil production industry. The cyclone performance was compared with a cone type cyclone and multi cyclone at the same experimental condition using water and oil mists generated by a humidifier and atomizer at the flow rate 1 to $2m^3/min$. The removal efficiency of total suspended water droplets by the novel cyclone, calculated using inlet and outlet concentrations measured by an optical particle counter, was 99% which is higher than 90% of oil droplet removal efficiency at $2m^3/min$. It might be due to the evaporation of small water droplets during the tests. The water and oil droplet removal performance of the novel cyclone based on the quality factor which is a function of pressure drop and removal efficiency was the highest among three cyclones. The results indicate that the cyclone could be an economical device to remove water and oil mists from shale gas generation processes where a huge three phase separator is commonly used.