• 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.

• 환경위생공학
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• 제14권2호
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• pp.1-7
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• 1999

In the tungsten industry as light source material, tungsten filament which used as light source material ould form after molybdenum wire which used as the center supporter for coil shape tungsten wire was removed. The purpose of this study is to develop new process named "hydrogen peroxide dissolution method". This process uses hydrogen peroxide, which is harmless to human body and oxidize molybdenum wire selectively. The results were as follows:1. The dissolution of molybdenum wire was proportion to a solution and contact surface of molybdenum wire. 2. The optimum $H_2O_2/H_2O$ were 1:0.5 ~ 1:1.75. 3. The time of dissolution was 65~70 minutes, and the PCS of sample were 20,800 PCS(1,820g). 4. Total cost($H_2O_2$, catalyst) was ￦19,088.

• 펄프종이기술
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• 제33권4호
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• pp.49-54
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• 2001

This study was carried out to acquire basic data for the bleaching of bamboo chemical pulp. Bamboo chemical pulps (alkaline sulfite (AS)-anthraquinone (AQ) pulp, Kraft pulp) were bleached with two kinds of multistage bleaching methods (CEDED, PDED) using the various kinds of bleaching agents. And, physical properties of bleached pulps were investigated. The conclusions obtained from the results were as follows; The yield of AS-AQ pulp bleached with four-stages bleaching method using the hydrogen peroxide and chlorine dioxide as a bleaching agents was higher than the other bleached pulps. The brightness of kraft pulp bleached with five-stages bleaching method using the chlorine and chlorine dioxide as a bleaching agents was higher than the other bleached pulps. The physical properties of kraft pulp bleached with four-stages bleaching method using the hydrogen peroxide and chlorine dioxide as a bleaching agents was higher than the other bleached pulps.

• 한국수소및신에너지학회논문집
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• 제28권6호
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• pp.649-656
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• 2017

At present, hydrogen is emerging as a future energy source based on environment-friendly aspect, creation of new industry, and enhancement of domestic energy security. In accordance with it, the world's leading automobile companies are focusing on the development and commercialization of hydrogen electric vehicle technology, and each country is strengthening its hydrogen fueling station deployment strategy for its own country. Furthermore, the supply of hydrogen fueling stations is actively promoting under national support. More than 500 hydrogen fueling stations are being constructed, operated and planned around the world. The introduction of hydrogen energy is also progressing in Korea, by announcing road-map to supply hydrogen electric vehicles and hydrogen fueling stations by year. However, there is insufficient discussion on the capacity of hydrogen fueling station in Korea. Therefore, this study suggests the optimum capacity of hydrogen fuelling station for domestic hydrogen economy.

• Nuclear Engineering and Technology
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• 제49권8호
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• pp.1748-1751
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• 2017

Reduced activation ferritic/martensitic (RAFM) steels are widely applied as structural materials in the nuclear industry. To investigate hydrogen's effect on RAFM steels' elastic properties and the mechanism of that effect, a procedure of first principles simulation combined with experiment was designed. Density functional theory models were established to simulate RAFM steels' elastic status before and after hydrogen's insertion. Also, experiment was designed to measure the Young's modulus of RAFM steel samples with and without hydrogen charging. Both simulation and experiment showed that the solubility of hydrogen in RAFM steels would decrease the Young's modulus. The effect of hydrogen on RAFM steels' Young's modulus was more significant in water-quenched steels than it was in tempering steels. This indicated that defects inside martensite, considered to be hydrogen traps, could decrease the cohesive energy of the matrix and lead to a decrease of the Young's modulus after hydrogen insertion.

• 신재생에너지
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• 제18권2호
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• pp.50-59
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• 2022

The Korean government announced the "1st Basic Plan for the Transition to Hydrogen Economy" in 2021 and declared the establishment of a hydrogen industry ecosystem by 2040. To build a low-carbon power system, resources that can efficiently accommodate renewable energy are required, and green hydrogen is considered a potential solution. This study analyzed the economic feasibility of green hydrogen-based sector coupling to reduce curtailment of renewable generation in the Jeju power system by 2025 under the scenario of with or without HVDC#3. The result showed that HVDC#3 significantly reduced the frequency of curtailment from 16.1% to 3.0%. In addition, green hydrogen-based sector coupling was an economically feasible option as result showed an IRR of 4.86% when HVDC#3 was connected and 11.45% when it was not under the condition of achieving 50% curtailment reduction. This study shows that the higher the level of renewable energy deployment, the more delayed the HVDC connection between Jeju and the main land, and the lower the SMP, the more economically feasible the green hydrogen-based sector coupling is. Furthermore, this study suggests that the policy goal of completely reducing curtailment is not economically efficient.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 추계학술발표논문집
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• pp.161-169
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• 2006

• 한국수소및신에너지학회논문집
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• 제17권1호
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• pp.98-108
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• 2006

본 연구에서는 이 단계 연속 바이오 수소/메탄 생산공정의 경제성을 조사하였다. 경제적 관점에서 다양한 수소 및 메탄 발효용 생물반응기를 비교 평가하였다. 이를 바탕으로 포도당으로부터 일 단계 수소발효를 위해 고온 trickling biofilter 반응기 (TBR, $100\;m^3$ 규모)를, 일 단계 반응의 부산물로 생성된 유기산과 알콜류의 이 단계 메탄전환을 위해 고온 upflow anaerobic sludge 반응기 (UASB; $700\;m^3$ 규모)를 선정하였다. 본 이 단계 공정의 수소생산 비용은 $$\;0.26/Nm^3$으로 계산되었고, 이는 고온 TBR 반응기만을 이용한 경우보다 약 30 % 낮았다. 이 단계 공정의 낮은 수소생산 비용은 높은 에너지 회수율과 낮은 슬러지 처리비용에 의한 것이었다. 생물학적 수소 생산공정의 경제성은 탄소원의 종류, 생물반응기의 형태 등 여러 인자에 의해 변경될 수 있으나, 본 연구결과는 향후 연구를 위한 유용한 기준으로 고려될 수 있다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2010년도 춘계학술발표회 논문집
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• pp.195-206
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• 2010

Xylan can be applied to improve the strength properties of paper; however the optical properties, such as brightness, are decreased significantly. To solve that problem, an applicable bleaching process is therefore desired. The aim of this research was to investigate the impact of hydrogen peroxide bleaching on hardwood kraft pulp pretreated with birchwood xylan by measuring optical properties (whiteness, brightness, opacity) as well as physical properties (tensile index, tearing index, bulk) of handsheets made from the bleached pulp. Hydrogen peroxide bleaching, as a kind of totally chlorine free (TCF) bleaching method, is quite important industrially for chemical pulp. In our work, the process variables of peroxide bleaching including bleaching temperature, time, initial pH and $MgSO_4$ dosage were studied. The results showed that both good mechanical properties and optical properties could be achieved when the operating parameters were controlled properly and therefore hydrogen peroxide bleaching was proved to be a suitable method for bleaching hardwood kraft pulp with adsorption of birchwood xylan.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.381-386
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• 2006

Many different types of bleaching chemicals and processes have been globally used for deinked pulp. Besides chlorine-free bleaching chemicals, hydrogen peroxide, and sodium dithionite that could be used without restriction for almost all types of fibers, chlorine-containing chemicals such as chlorine dioxide and sodium hypochlorite have also used throughout the world. Even though hydrogen peroxide is commonly used in newsprint, it could not effectively increase brightness. Experimental evaluation on the possibility of using formamidine sulfinic acid (FAS), a reducing agent, for bleaching a wood-containing deinked pulp has been carried out in this study. The effect of bleaching efficiency for FAS on operational conditions and chemical concentrations compaired to hydrogen peroxide in one and two stages was studied. FAS bleaching showed higher brightness at high temperature and low consistency, and vice versa for peroxide one. Bleaching with sodium silicate and DTPA in FAS and peroxide stage showed better results than cases without them. Sodium silicate and chelant seemed minimize the influence of transition metal ions, including manganese and iron ions, which induce both bleaching agents to decompose. As a result, FAS as a reducing agent seems more effective than hydrogen peroxide for increasing brightness and reducing yellowness. FAS and FAS sequence seemed more efficient than the other two stages of bleaching sequences with regard to the best brightness level obtained. When bleaching was conducted with FAS, COD load was just about one-third compared to peroxide, and brightness stability of the bleached pulp appeared better than peroxide after UV light irradiation.