• Journal of Ocean Engineering and Technology
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• v.36 no.3
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• pp.168-180
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• 2022

The IMO has decided to proceed with the early introduction of EEDI Phase 3, a CO₂ emission regulation to prevent global warming. Measures to reduce CO₂ emissions for ships that can be applied immediately are required to achieve CO₂ reduction. We set six different CO₂ emission scenarios according to the type of ship and fuel, and designed a monoethanolamine-based CO₂ capture process for ships using a rate-based model of Aspen Plus v10. The simulation model using Aspen Plus was validated using pilot plant operation data. A ship inevitably tilts during operation, and the performance of a tilted column decreases as its height increases. When configuring the conventional CO₂ capture process, we considered that the required column heights were so high that performance degradation was unavoidable when the process was implemented on a ship. We applied a parallel column concept to lower the column height and to enable easy installation and operation on a ship. Simulations of the parallel column confirmed that the required column height was lowered to less than 3 TEU (7.8 m).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.1
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• pp.9-22
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• 2023

Spin-off pyroprocessing technology and inert anode materials to replace the conventional carbon-based smelting process for critical materials were introduced. Efforts to select inert anode materials through numerical analysis and selected experimental results were devised for the high-throughput reduction of oxide feedstocks. The electrochemical properties of the inert anode material were evaluated, and stable electrolysis behavior and CaCu generation were observed during molten salt recycling. Thereafter, CuTi was prepared by reacting rutile (TiO₂) with CaCu in a Ti crucible. The formation of CuTi was confirmed when the concentration of CaO in the molten salt was controlled at 7.5mol%. A laboratory-scale electrorefining study was conducted using CuTi(Zr, Hf) alloys as the anodes, with a Ti electrodeposit conforming to the ASTM B299 standard recovered using a pilot-scale electrorefining device.

• Journal of Hydrogen and New Energy
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• v.34 no.6
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• pp.689-697
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• 2023

The high-pressure hydrogen valve is intended to supply hydrogen charged at high pressure in the hydrogen tank to the fuel cell stack, which decompresses high-pressure hydrogen gas to low pressure and primarily limits the excessive flow. It consists of a pilot valve, a main valve, and a excessive flow valve to operate in a wide pressure range from 2 to 70 MPa of charging pressure. The opening characteristics of the valve were confirmed by computation fluid dynamics applying the moving grid technique. The behavior of the valve was predicted by predicting the force acting on the valve over time. In addition, the difference in behavior according to supply pressure was compared.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.1-11
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• 2006

The aim in this study is to develop the combined EGR system with a non-thermal plasma reactor for reducing exhaust emissions and improving fuel economy in turbo intercooler ECU common-rail diesel engines. In this study, the characteristics of soot, CO and $CO_2$ emissions under four kinds of engine loads are experimentally investigated by using a four-cycle, four-cylinder, direct injection type, water-cooled turbo intercooler ECU common-rail diesel engine with a combined plasma exhaust gas recirculation(EGR) system operating at three kinds of engine speeds. The EGR and non-thermal plasma reactor system are used to reduce $NO_x$ emissions, and the non-thermal plasma reactor and turbo intercooler system are used to reduce soot and THC emissions. The plasma system is a flat-to-flat type reactor operated by a plasma power supply. The fuel is sprayed by pilot and main injections at the variable injection timing between BTDC $15^{\circ}$ and ATDC $1^{\circ}$ according to experimental conditions. It is found that soot emissions with increasing EGR rate are increased, but are decreased as the applied electrical voltage of the non-thermal plasma reactor is elevated at the same engine speed and load. Results also show that CO and $CO_2$ emissions are increased as EGR rate is elevated, and CO emissions are increased, but $CO_2$ emissions are decreased as the applied electrical voltage of the non-thermal plasma reactor is elevated at the same engine speed and load.

• Resources Recycling
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• v.15 no.1 s.69
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• pp.37-45
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• 2006

For treating a huge amount of plastic waste with the environment problem, pyrolysis of plastic waste into alternative fuel oil is one or important issue in recycling methods. This study was introduced over the trend or generation of plastic waste, in Korea pyrolysis technology in domestic and foreign countries, basic technology in pyrolysis process and new technology of pyrolysis developed in KIER (Korea Institute of Energy research). The characteristics of process developed in KIER are the continuous loading treatment or mixed plastic waste with an automatic control system, the minimization of wax production by circulation pyrolysis system in non-catalytic reactor, the reuse of gas produced and the oil recovery from sludge generated in pyrolysis plant, which have greatly the advantage economically and environmetally. The experiment result data in 300 ton/yr pilot plant showed about $81\;wt\%$ liquid yield for 3 days continuous reaction time, and also the boiling point distribution of light oil (LO) and heavy oil (HO) produced in distillation tower was a little higher than that of commercial gasoline and diesel, respectively.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.34-46
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• 2005

For treating a huge amount of plastic waste with the environment problem, pyrolysis of plastic waste into alternative fuel oil is one of important issue in recycling methods. This study was introduced over the trend of generation of plastic waste, pyrolysis technology in domestic and foreign countries, basic technology in pyrolysis process and new technology of pyrolysis developed in KIER (Korea Institute of Energy Research). The characteristics of process developed in KIER are the continuous loading treatment of mixed plastic waste with an automatic control system, the minimization of wax production by circulation pyrolysis system in non-catalytic reactor, the reuse of gas produced and the oil recovery from sludge generated in pyrolysis plant, which have greatly the advantage economically and environmetally. The experiment result data in 300 ton/yr pilot plant showed about 81 wt% liquid yield for 3 days continuous reaction time, and also the boiling point distribution of light oil (LO) and heavy oil (HO) produced in distillation tower was a little higher than that of commercial gasoline and diesel, respectively.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.546-555
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• 2019

The purpose of this study was to improve the performance of the bogie-type crematory, which is the mainstream of domestic crematory equipment. A field scale technology was investigated via increasing the volume by changing the shape of the furnace and reducing the cremation time and saving the energy usage through the optimization of burner combustion control. First, the optimized structural design through thermal flow analysis increases the volume of the main combustion chamber by about 70%, which increases the residence time of the combustion flue gas. A designed pilot crematory was then installed and the combustion behavior was tested under various operating conditions and the optimum operating plan was derived from for each furnace shape. Based on the results, the practically applicable crematory was designed and installed at Y crematorium in the P City. Optimal combustion conditions could be derived through operating the demonstration crematory furnace. The crematory time and fuel consumption could be minimized by increasing the energy efficiency by increasing the residence time of high temperature combustion flue gas. In other words, the crematory time and fuel consumption were 38 min and $21.8Nm^3$, respectively which were shortened by 44.1 and 54.4% lower than that of the existing crematory, respectively.

• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.400-407
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• 2019

Oxy-combustion with a circulating fluidized bed (Oxy-CFBC) technology has been paid attention to cope with the climate change and fuel supply problem. In addition, Oxy-CFBC technology as one of the methods for carbon dioxide capture is an eco-friendly that can reduce air pollutants, such as $SO_2$, NO and CO through a flue gas recirculation process. The newly developed $100kW_{th}$ pilot-scale Oxy-CFBC system used for this research has been continuously utilizing to investigate oxy-combustion characteristics for various fuels, coals and biomasses to verify the possibility of fuel diversification. The anthracite is known as a low reactivity fuel due to a lot of fixed carbon and ash. Therefore, this study aims not only to improve combustion efficiency of an anthracite, but also to capture carbon dioxide. As a result, compared to air-combustion of sub-bituminous coal, oxy-combustion of anthracite could improve 2% combustion efficiency and emissions of $SO_2$, CO and NO were reduced 15%, 60% and 99%, respectively. In addition, stable operating of Oxy-CFBC could capture above 94 vol.% $CO_2$.

• Journal of Science Education
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• v.46 no.1
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• pp.93-108
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• 2022

The purpose of this study is to develop a STEAM program that can be used in the high school credit system to be fully implemented in 2025, and to examine its validity and effectiveness. The STEAM program analyzed the 2015 revised curriculum centering on science, technology, and engineering through the 2015 revised curriculum analysis, and then selected the five latest issues: hydrogen fuel, climate crisis, data science, appropriate technology, and barista. In accordance with this self-developed program development format (frame), it was developed for seven months through a process of group deliberation. The draft of the STEAM program for 29 sessions of five types, developed to indirectly experience the career path and occupation of high school students, was verified through consultation with 2 STEAM education experts. It was applied at five different high schools for a pilot implementation. As a result of the pilot application, it was confirmed that the students' STEAM attitude significantly improved in the post-test than the pre-test, and the students' high satisfaction with the program was confirmed. In addition, through an interview with the pilot application teacher, it was positively evaluated that 'the content and level of the program are suitable and through experience solving real-life problems, you can apply the content knowledge of related subjects and have an opportunity to experience careers.' Based on the results of the pilot application, the high school credit system STEAM program for students and teachers was finally completed in 29 lessons of five types. Through this study, the development and operation of the next-generation STEAM program that can be applied in the high school credit system should be actively developed, and a plan to improve teachers' professionalism so that the high school credit system can be established and operated properly for blended classes triggered by COVID-19. The necessity of design was suggested. This study is expected to be used as basic data for the development and operation of STEAM programs in the high school credit system, which will be fully implemented in 2025.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.1
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• pp.65-78
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• 2007

The pollutants (Rn, CH, CO, HS, radioactive gas from radiolysis) were generated from the process of construction and operation of underground repository, and after disposal of low-intermediate radioactive waste inside there must be controlled by a ventilation system to distribute them in area where enough air is supported. Therefore, a suitable technical approach is needed especially at an underground repository that is equipped with many entry tunnels, storage tunnels, exhaust-blowing tunnels, and vertical shafts in complicated network form. For the technical approach of such a ventilation system, WIPP (Waste Isolation Pilot Plant) in U. S and SFR (Slutforvar for Reaktorafall) low-intermediate radioactive waste repository in Sweden were selected as the models, for calculating the required air quantity, organizing a ventilation network considering cross section, length, surface roughness of the air passage, and describing a calculation of resistance of each circuit. Based on these procedures, a best suited ventilation system was completed with designing proper capacity of fans and operating plan of vertical shafts. As a result of comparing the two repositories based on the geometry dimensions and ventilation facility equipment operation, more parallel circuit as in WIPP, brought decrease in resistance for entire system leading to reduce of operating costs, and the larger cross-sectional area of the SFR, the greater the percentage of disposal capacity. Accordingly, the mixture of parallel circuit of WIPP repository for reducing resistance and SFR repository formation for enlargement of disposal capacity would be the most rational and efficient ventilation system.