• Proceedings of the Korea Water Resources Association Conference
• /
• 2022.05a
• /
• pp.338-338
• /
• 2022

2050년까지 탄소중립 사회구현을 위한 방안을 모색하기 위한 논의가 활발히 이루어지고 있으며, 이에 수소도시 실현을 통한 화석연료와 탄소배출을 줄이는 방법들이 주목받고 있다. 그린수소가스의 생산 및 운송, 저장과 가스형태의 수소를 액화 수소로 압축시키는데 드는 막대한 에너지가 소비되는 문제점에 대한 대안책으로 암모니아를 캐리어로 이용하여 운송 및 저장하고 수소를 생산하는 방식이 널리 이용되고 있으며, 효율 향상을 위한 추가 연구들이 진행되고 있다. 또한, 중국에 대한 우리나라의 요소수 수입 의존도가 높음에 따라 요소수 주요성분인 암모니아와 탄산가스를 합성한 요소수 생산 방식에 대한 연구가 이루어지고 있다. 하지만, 현재 산업계에서 석탄과 같은 석유자원에서부터 암모니아를 추출하는 방식이 가장 널리 적용되고 있다. 이와 같은 암모니아 생산에 대한 석유자원 의존도를 낮추기 위한 방안에 대한 도출 및 연구가 필요한 실정이다. 이와 같은 상황에 맞춰 본 연구에서는 생활하수로부터 암모니아를 추출하는 방법으로서 통합형 막증류 시스템에 연구하고자 한다. 분뇨, 음식물 폐기물 침출수 등 유기성 폐기물의 수집, 운송 및 처리에서 발생되는 생활하수에는 암모니아성 질소 및 탄소가 다량 포함되어 있어 이를 추출하여 순수한 암모니아 생산에 대해 석유자원을 대체할 수 있는 대안으로서의 효용성을 갖고 있다. 하지만, 이와같은 생활하수는 암모니아성 질소 이외 성분들이 고농도로 포함되어 있어 암모니아 생산에 대한 원료만을 선택적으로 분리하는데 많은 어려움이 있다. 본 연구에서는 생활하수에서 암모니아를 선택적으로 분리하는 방법으로서 막증류(Membrane Distillation, MD) 기반의 통합 암모니아 분리기술을 개발하고 이에 대한 적용 가능성과 효율 향상에 대해 평가 하였다. 또한, 암모니아와 탄산가스 합성을 통한 요소수 생산 방법에 대한 연구를 진행하였다.

• Proceedings of the Korea Society of Poultry Science Conference
• /
• 2002.11a
• /
• pp.90-91
• /
• 2002

In order to study the effect of dietary krill meal on the performance and the utilization of protein and energy, broiler chicks fed on the experimental diets containing 0.0%, 0.5% and 1.0% krill meal, respectively, and injected Salmonella typhimurium lipopolysacharide(LPS) (Immunological stress) in 2nd week of age during 3 weeks of experimental period. Dietary krill meal did not affect daily gain and feed efficiency but the immunological stress lowered daily gain and feed intake and nitrogen balance and increased liver and spleen weight and the energy utilization of bird. The uric acid excretion was accelerated by immunological stress.

• New & Renewable Energy
• /
• v.19 no.2
• /
• pp.13-22
• /
• 2023

With the increased interest in renewable energy, various hydrogen production technologies have been developed. Hydrogen production can be classified into green, blue, gray, and pink hydrogen depending on the production method; each method has different technical performance, costs, and CO₂ emission characteristics. Hence, selecting the technology priorities that meet the company strategy is essential to develop technologically and economically feasible projects and achieve the national carbon neutrality targets. In addition, in early development technologies, analyzing the technology investment priorities based on the company's strategy and establishing investment decisions such as budget and human resources allocation is important. This study proposes a method of selecting priorities for various hydrogen production technologies as a specific implementation plan to achieve the national carbon neutrality goal. In particular, we analyze key performance indicators for technology, economic feasibility, and environmental performance by various candidate technologies and suggest ways to score them. As a result of the analysis using the aforementioned method, the priority of steam methane reforming (SMR) technology combined with carbon capture & storage (CCS) was established to be high in terms of achieving the national carbon neutrality goal.

• Transactions of the Korean hydrogen and new energy society
• /
• v.34 no.5
• /
• pp.389-397
• /
• 2023

This study compares domestic and foreign research on renewable energy-based water electrolysis clean hydrogen. Domestic studies from 2010 to 2023 focused on technological efficiency, energy efficiency, and system efficiency, with few analyzing infrastructure and technology trends. Overseas research initially focused on technological efficiency and stability, but has since shifted to economic and environmental impact, policy effectiveness, industry-university-research cooperation, and sustainability. To improve water electrolysis technology production, this study suggests prioritizing technology stability over efficiency, resolving government regulations and resident acceptance issues, promoting industry-university-institute cooperation for rapid commercialization of research results, and developing a strategy for sustainable development of renewable energy-based water electrolysis technology.

• Transactions of the Korean hydrogen and new energy society
• /
• v.34 no.3
• /
• pp.235-245
• /
• 2023

Techno-economic analyses on a 5-MW water electrolysis system for hydrogen production, operated in Jeju Island where the portion of renewable energy in the power grid is the highest in Korea, have been performed. The cost of hydrogen production and the economic feasibility of the hydrogen production system have been mainly analyzed based on the levelized-cost-of-hydrogen model. The effects of carbon emission trading and renewable power purchase method have been considered to reduce the cost of green hydrogen production in the case studies. This economic analysis model is expected to be used to derive a business model for green hydrogen production.

• Journal of the Korean Institute of Gas
• /
• v.23 no.3
• /
• pp.7-19
• /
• 2019

In this study, a model was developed for estimating deliverability considering the pressure dependent permeability and predicting production profile with Material Balance Equation(MBE) for Coalbed Methane(CBM) fields. The estimated deliverability was compared with the conventional deliverability based on CBM well testing data with coefficient of determination($R^2$). As a result, the former was 0.76 and the latter was 0.69. It was confirmed that the deliverability which consider the pressure dependent permeability is more adoptable when representing the productivity of CBM fields. Through this process, in order to calculate pressure dependent permeability when well testing data exist, a method to infer reservoir pressure within the radius of investigation was proposed. The production profile of 31 gas wells was predicted for 15 years, using the estimated deliverability and the MBE. After that, the results was compared with simulation results of the literature. The simulation results did not account the pressure dependent permeability and the developed model results considered that. As the applied field permeability rised 1.17 times, field production rate was increased approximately 15% than the literature results. According to other researches, the permeability of CBM fields can be rise 6 ~ 25 times. For these cases, the production profiles may have significant difference with conventional gas fields.

• Journal of Energy Engineering
• /
• v.17 no.3
• /
• pp.145-152
• /
• 2008

Approaching to the era of high energy price and energy sources scarcity, the demand for governmental intervention to mitigate the short-term shocks is highly increasing. When any energy policy is implemented, double-side effects would be derived. To begin with positive aspect, by decreasing energy import, unnecessary currency outflow can be prevented and the resultant saved money will be appropriately allocated. Furthermore, industrial competitiveness will be assured by reducing use of expensive energy. On the contrary, inappropriate energy saving policy may lead to unexpected negative effects that would hinder improvement in productivity due to indiscreet replacing energy by equipments. In order to enhance effectiveness of energy policy, efforts should be made in advance to understand the energy use pattern of each industry sector which composes the economy. Therefore, in this study, an energy input-output method, one of the macroscopic approaches, is applied to analyze energy use patterns of each industry sector in Korea. Using this method, a quantitative assessment is performed to obtain the energy use intensity and the amount of energy uses with respect to energy types.

• Electronics and Telecommunications Trends
• /
• v.29 no.5
• /
• pp.72-85
• /
• 2014

현대 산업사회는 시장의 불확실성과 기술의 불확실성이 공존하면서, 글로벌 경제의 저성장에 대한 우려, 불확실성의 증대가 더욱 크게 산업 전반의 스트레스로 작용하고 있다. 이는 R&D-생산-마케팅 자원의 낭비를 초래하게 되고, 시대/경제/산업의 변화는 더욱 이러한 환경을 가속화시키고 있다. 에너지 분야에서도 환경 위기, 지속가능 에너지, 화석연료 고갈, 기후변화 등의 당면 문제를 해결하지 못한다면, 인류 공멸의 위기에 직면할 것이다. 정부에서는 창조경제의 주요 아젠다로 에너지 분야의 다양한 정책과 기술개발을 드라이브하고 있으며, 에너지 ICT 융합을 통해 이를 실현하고자 하고 있다. 본고에서는 에너지 ICT 기술의 개발동향과 발전방향 및 트렌드를 분석해 보고, 현재 진행 중인 국내(ETRI)의 기술개발 사례를 소개하고자 한다.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
• /
• v.29 no.1
• /
• pp.57-67
• /
• 2000

최근 국민소득수준의 향상을 따라 여름철 전력 수요가 폭증하므로 전력안정 공급을 위한 특별 대책이 필요한 실정이고 환경적인 측면이나 수용가 입장에서 만족스러운 새로운 냉·난방, 전기 공급시스템의 개발·적용이 필요하다. 선진국의 경우, 소규모의 집단에너지 공급이 주류를 이루고 있으며 특히 소규모 열병합 발전시 생산되는 전기, 지역난방열 이외에 냉방에 필요한 냉수를 중앙열원에서 동빌딩을 중심으로하는 구역형 집단에너지 시스템(Community Energy Supply System)등 소규모지역 난냉방 공급방식이 활성화되어 있으므로, 우리나라에서도 냉방/난방/전기부하 패턴 및 하절기 피크부하 경감에 대한 기여도 등을 고려한 경제성있는 최적시스템 구성이 가능한지 검토할 필요가 있다. 소규모 집단에너지사업은 대규모 사업과는 달리 적정 수요예측이 가능하므로 효율적인 초기 투자가 이루어질 수 있으며, 상업용 및 사업용 빌딩 등을 중심으로 부하밀도가 높은 구역을 대상으로 하명서 해당 부하패턴에 적합한 효율적인 시스템의 구성을 통해 수익성이 확보된다면 국가 에너지절약 및 한전의 여름철 전력 피크부하 경감, 대기 환경공해 감소, 도심 도시미관 향상 등의 사업효과가 기대된다. 본문에서는 이러한 소규모 집단에너지시스템 개요 및 국내외 공급 현황, 국내 적용환경, 적용 가능에너지 검토 열원시스템의 기본방향 등에 대하여 언급하고자 한다.

• Korean Journal of Poultry Science
• /
• v.20 no.2
• /
• pp.73-92
• /
• 1993

This study was conducted to investigate the effect of dietary metabolizable energy and crude protein levels on the performance and abdominal fat pad of broiler chicks. A total of 702, a day-old chicks were alloted into nine groups differing in dietary metabolizable energy (2,800, 3,000 and 3, 200kcal/kg) and crude protein(16, 18 and 20%) level from July 10 to September 4, 1990 for 8 weeks. The results obtained were summarized as follows. 1. Body weight gain was significantly increased by increasing of metabolizable energy level (p＜0.05), but there was no significant difference between 2,800kcal/kg and 3,000kcal/kg, or 3,000 kcal/kg and 3,200kcal/kg of metabolizable energy, and there was no significant difference among crude protein levels. 2. Feed consumption tended to decrease by increasing of metabolizable energy and crude protein levels, but there was no significant difference among treatments. 3. Feed conversion was significantly improved by increasing of metabolizable energy level (p＜0.01), and it was showed a tendency to improve by increasing crude protein level(p＜0.05), but the difference between 18% and 20% of crude protein level was not significant. 4. Eviscerated yield was not different significantly among treatments. 5. Abdominal fat pad was significantly increased by increasing of metabolizable energy level (p＜0.01), but there was no significant difference between 2,800kcal/kg and 3,000kcal/kg, or 3,000kcal/kg and 3,200kcal/kg of metabolizable energy. On the other hand, abdominal fat pad in 20% of crude protein level was significantly lower than those in 16% and 18% of crude protein level (p＜0.01). 6. The feed cost per kilogram body weight gain tended to decrease by increasing of metabolizable energy level, and that in 18% of crude protein level was slightly lower than those in 16% and 20% of crude protein level, but there was no significant difference among treatments.