• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.10a
• /
• pp.611-612
• /
• 2012

• 전기의세계
• /
• v.28 no.10
• /
• pp.3-8
• /
• 1979

정확하게 예측할 수는 없지만 현상태대로 나간다면 적어도 20년 후에는 석유생산의 피이크를 맞이하고 30년후에는 고갈될 것이라고 내다보는 전문가가 많다. 그렇다면 우리는 하루라도 빨리 석유를 대신할 수 있는 신에너지원을 찾아야만 할 것이다. 우리가 사용하고 있는 에너지는 크게 나누어 전기와 연료의 두가지로 된다. 전기에 대해서는 새삼스럽게 이야기 할것 없고 연료라는 에너지는 자동차를 달리게 하고 공장을 움직이고 빌딩의 온방에 쓰이는 등 이것역시 문명사회에 불가결한 것이다. 이중 문제가 되고 있는 것이 석유에 의한 발전 곧 확력발전부문의 전망디다. 한편 연료에 대해서는 종래 주종을 이루어왔던 석유를 대신해서 석탄의 액화, 가스화 물의 분해에 의해서 만들어지는 수소연료 등이 생각되고 있는데 과연 고갈된지 않는 새로운 에너지로서는 어떤 것이 있는가 또 현재 이들이 어느정도 개발되고 있는가를 알기쉽게 2-3회로 간추려서 소개해 보기로 한다.

• 전기의세계
• /
• v.28 no.9
• /
• pp.30-34
• /
• 1979

정확하게 예측할 수는 없지만 현상태대로 나간다면 적어도 20년 후에는 석유생산의 피이크를 맞이하고 30년후에는 고갈될 것이라고 내다보는 전문가가 많다. 그렇다면 우리는 하루라도 빨리 석유를 대신할 수 있는 신에너지원을 찾아야만 할 것이다. 우리가 사용하고 있는 에너지는 크게 나누어 전기와 연료의 두가지로 된다. 전기에 대해서는 새삼스럽게 이야기 할것 없고 연료라는 에너지는 자동차를 달리게 하고 공장을 움직이고 빌딩의 온방에 쓰이는 등 이것역시 문명사회에 불가결한 것이다. 이중 문제가 되고 있는 것이 석유에 의한 발전 곧 확력발전부문의 전망디다. 한편 연료에 대해서는 종래 주종을 이루어왔던 석유를 대신해서 석탄의 액화, 가스화 물의 분해에 의해서 만들어지는 수소연료 등이 생각되고 있는데 과연 고갈된지 않는 새로운 에너지로서는 어떤 것이 있는가 또 현재 이들이 어느정도 개발되고 있는가를 알기쉽게 2-3회로 간추려서 소개해 보기로 한다.

• Transactions of the Korean hydrogen and new energy society
• /
• v.31 no.4
• /
• pp.363-371
• /
• 2020

Recently, the technologies to utilize the cold energy of liquefied natural gas (LNG) have attracted significant attention. In this paper, thermodynamic performance analysis of combined cycles consisting of ammonia Rankine cycle (AWR) and organic Rankine cycle (ORC) with LNG Rankine cycle to recover low-grade heat source and the cold energy of LNG. The mathematical models are developed and the effects of the important system parameters such as turbine inlet pressure, ammonia mass fraction, working fluid on the system performance are systematically investigated. The results show that the thermal efficiency of AWR-LNG cycle is higher but the total power production of ORC-LNG cycle is higher.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 1999.02a
• /
• pp.194-197
• /
• 1999

Thermodynamic cycle analysis has been performed to maximize the liquid amount for two hydrogen liquefaction systems using two-stage GM(Gifford-McMahon) refrigerator. the optimal operating conditions have been analytically sought with real properties of normal hydrogen for the two-stage GM direct contact system and the two-stage GM precooled L-H (Linde-Hampson) system. In the precooled system, there existed optimal values for compressed mass flow and compressed pressure to maximize the liquefied mass. It was recommended to use a cryocooler, which had a large precooling capacity between 70 and 100K.

• Journal of the Korean Wood Science and Technology
• /
• v.18 no.4
• /
• pp.79-85
• /
• 1990

Many kinds of acetosolv lignin including ricestraw and spruce lignin were pyrolyzed. and liquefied in the autoclave reactor using 50% tetralin and m-cresol solution respectively as soluble solvent and Co-Mo as catalyst. In order to promote deoxyhydrogenolysis reaction $H_2$ gas was supplied into the reactor. The ratio between lignin and the soluble solvent are lg and 10cc. The reaction conditions are $200^{\circ}-700^{\circ}C$ of reaction temperature, 10-50 atms of reaction pressure and 100-500rpm of the reactor stirrer. By the deoxyhydrogenolysis liquefaction reaction, the main chemical structures of lignin which are aryl-alkyl-${\beta}$-0-4 ether, phenylcoumaran and biphenyl etc. are easily destroyed into liqufied aromatic compounds and aliphatic compunds linked with aromatic compounds. The percent yield of monomeric phenols on the weight bvase of lignin reacted reached to 12-14% by the chemical analytic GC-MS etc.

• Transactions of the Korean hydrogen and new energy society
• /
• v.31 no.2
• /
• pp.259-264
• /
• 2020

In this study, comparison study has been performed between two-stage compression and a vapor-recompression refrigeration cycle and a liquefaction using LNG cold heat. When using a first method using two-stage compression and a refrigeration cycle, at least three compressors are required, however when using LNG cold heat, no compressor is required since carbon dioxide can be pumped after condensing with the heat exchange with -160℃ of LNG. Through this study, we can save more than one hundred million KRW annually by using LNG cold heat instead of using gas compression and refrigeration cycle.

• Journal of the Korean Professional Engineers Association
• /
• v.12 no.4
• /
• pp.26-31
• /
• 1979

The Natural Gas and petroleum have the same Origin, Namely, Ocean bottom deposits of the marine plant, plankton which are subdued to the biological action of the bacterium under the anaerobic circumstance, and changed to the hydrocarbon gas and oils. and such resources are appeared in the aqueous sedimentary rocks in the tertiary. There are three types of gas field, which are oil well gas field, structural gas field and water soluble gas field.

• Transactions of the Korean hydrogen and new energy society
• /
• v.30 no.4
• /
• pp.297-302
• /
• 2019

In this paper, the power generation efficiency increase has been studied for a Rankine cycle using both supercritical carbon dioxide as a working fluid and LNG as a coolant with PRO/II with PROVISION release 10.0 from Aveva company. Peng-Robinson equation of the state model with Twu's alpha function was selected for the modeling of the power generation cycle using LNG cold heat. Power generation efficiency was increased from 24.82% to 57.76% when using LNG as a coolant for supercritical carbon dioxide power generation cycle.

• Transactions of the Korean hydrogen and new energy society
• /
• v.34 no.5
• /
• pp.549-554
• /
• 2023

In this paper, three kinds of studies have been completed to obtain highly purified carbon dioxide having more than 7N purity as an electronic grade quality. PRO/II with PROVISION release January 2023 from AVEVA company was used, and Peng-Robinson equation of the state model with Twu's alpha function was selected for the modeling of the cryogenic distillation process. When using LN2 cold heat, we can obtain highest recovery of carbon dioxide as a bottom product for a cryogenic distillation column.