• Advances in Energy Research
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• 제7권2호
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• pp.101-121
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• 2020

Coal has made a wonderful contribution to the production of cheap electricity. Coal based power plants have been the backbone of world's electricity for a long time now. Coal while being cheap and easily available is also a source of various solid, liquid and gaseous effluents which are responsible for the environmental degradation. Environmental issues caused by coal need to be studied and analyzed, then a common global consensus must be formed. Efficient action must be taken against each and every type of pollutant that is produced by this particular industry. The research aims to provide a brief overlook of the environmental impact of India's coal-based power plants. The aim of this study is to introduce a novel environmentally feasible energy scenario for the future of Indian power sector which has been named as "OPES". OPES is mathematically simulated using the combination of GAMS and LEAP. OPES is simple to comprehend and can be reproduced easily for other case studies as well. Results show that OPES can help the Indian power sector to minimize its environmental impact without causing any problems in the energy supply.

• 대한안전경영과학회지
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• 제17권1호
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• pp.271-279
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• 2015

Global warming has pressured companies to put a greater emphasis on environment management which allows them to reduce environmental impact and costs of their operations. In Korea, the coal-fired power plants take a large account of electricity generation at 31.7% of the total electricity usage in 2014. Thus, environmental impact of coal-fired power plants is significant. This paper illustrated how to compute environmental impact and costs in electricity generation at a coal-fired power plant using MFCA methodology. Compared to the traditional accounting, an advantage of MFCA is to provide information on electricity generation costs and environmental wastes incurring throughout the production process of electricity. Based on MFCA, the coal-fired power plant was able to reduce production cost of electricity by 52.3%, and environmental wastes by 47.7%. As a result, MFCA seemed to be an effective tool in environmental management for power plants.

• Architectural research
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• 제18권2호
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• pp.59-64
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• 2016

Since the massive power outages that hit across the nation in September 2011, a growing imbalance between energy supply and demand has led to a severe backup power shortage. To overcome the energy crisis which is annually repeated, a policy change for deriving energy supply from renewable energy sources and a demand reduction strategy has become essential. Buildings account for 18% of total energy consumption and have great potential for energy efficiency improvements; it is an area considered to be a highly effective target for reducing energy demand by improving buildings' energy efficiency. In this regard, retrofitting buildings to promoting environmental conservation and energy reduction through the reuse of existing buildings can be very effective and essential for reducing maintenance costs and increasing economic output through energy savings. In this study, we compared the energy reduction efficiency of national power energy consumption by unit production volume based on thermal power generation, renewable energy power generation, and initial and operating costs for a building retrofit. The unit production was found to be 13,181GWh/trillion won for bituminous coal-fired power generation, and 5,395GWh/trillion won for LNG power generation, implying that LNG power generation seemed to be disadvantageous in terms of unit production compared to bituminous coal-fired power generation, which was attributable to a difference in unit production price. The unit production from green retrofitting increased to 38,121GWh/trillion won due to the reduced energy consumption and benefits of greenhouse gas reduction costs. Renewable energy producing no greenhouse gas emissions during power generation and showed the highest unit production of 75,638GWh/trillion won, about 5.74 times more effective than bituminous coal-fired power generation.

• 한국연소학회지
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• 제19권3호
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• pp.8-17
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• 2014

The aims of this research were to evaluate effects of biomass co-firing to pulverized coal power plants and the variation of co-firing ratios on the plant efficiency related to power consumption of auxiliary system and flue gas characteristics such as production and component by process simulation based on the existing pulverized coal power plant. In this study, four kinds of biomass are selected as renewable fuel candidates for co-firing: wood pellet(WP), palm kernel shell(PKS), empty fruit bunch(EFB) and walnut shell(WS). Process simulation for various biomass fuels and co-firing ratios was performed using a commercial software. Gas side including combustion system and flue gas treatment system was considering with combination of water and steam side which contains turbines, condenser, feed water heaters and pumps. As a result, walnut shell might be the most suitable as co-firing fuel among four biomass since when 10% of walnut shell was co-fired with 90% of coal on thermal basis, flue gas production and power consumption of auxiliary systems were the smallest than those of other biomass co-firing while net plant efficiency was relatively higher than those of other biomass co-firing. However, with increasing walnut shell co-firing ratios, boiler efficiency and net plant efficiency were expected to decrease rather than coal combustion without biomass co-firing.

• Advances in concrete construction
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• 제4권4호
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• pp.231-242
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• 2016

The major problem of a coal combustion-based power plant is that it creates large quantity of solid wastes. So, to achieve the gainful use of waste materials and to avoid other environmental problems, this study was undertaken. The quantity of coal ash by-products, particularly coal fly ash and coal bottom ash has been increasing from the coal power plants around the world. The other objective of this study was to explore the possibility of utilization of coal ash in the production of ash bricks. In 15 different mixes, Mix Designation M-1 to M-15, the varying percentages of lime and gypsum were used and sand was replaced with coal bottom ash. Further, it has been noticed that the water absorption and compressive strength of mix M-15 is 13.36% and 7.85 MPa which is better than the conventional bricks. The test results of this investigation show that the prism strength of coal ash masonry prisms was more than that of the conventional bricks.

• 플랜트 저널
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• 제6권2호
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• pp.70-77
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• 2010

This study investigated the characteristics of co-combustion of mixed anthracite (domestic and Vietnam) and bituminous coal (Sonoma, Australia) at circulating fluidized bed boiler in Donghae thermal power plant when mixing ratio of bituminous coal is variable. Co-combustion of bituminous coal contributes to improvement in general combustion characteristics such as moderately retaining temperature of furnace and recycle loop, reducing unburned carbon powder, and reducing discharge concentration of NOx and limestone supply owing to improvement in anthracite combustibility as the mixing ratio was increased. However, bed materials were needed to be added externally when the mixing ratio exceeded 40% because of reduction in generating bed materials based on reduction in ash production. When co-combustion was conducted in the section of 40 to 60% in the mixing ratio while the supplied particles of bituminous coal was increased from 6 mm to 10 mm, continuous operation was shown to be possible with upper differential pressure of 100 mmH2O (0.98 kPa) and more without addition of bed materials for the co-combustion of mixed anthracite and bituminous coal (to 50% or less of the ratio) and that of domestic coal and bituminous coal (to 60% of the ratio).

• 자원환경지질
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• 제57권3호
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• pp.281-292
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• 2024

북한에서 석탄은 전력 생산은 물론 산업용, 가정상업용 등 수송부문을 제외한 모든 에너지 수요부문에서 중추적 역할을 담당하는 주종에너지원이다. 북한은 전체 전력의 절반 정도를 석탄발전을 통해 생산하며, 모든 산업체의 열과 동력을 석탄에 의존하고 있다. 아울러 장기간 동안 대중 수출품목으로서 외화 획득에 지대한 기여를 하여 왔다. 그러나 1980년대 이래로 장기간 동안 무분별한 채탄으로 인해 대부분의 광산은 심부화가 급속도로 진행 되었고 광산설비의 노후화, 신규설비의 투자부족, 유류와 전력의 부족, 자재 공급 곤란, 잦은 수해로 인한 피해까지 겹치면서 1980년대 후반부터 석탄 생산량은 뚜렷하게 감소 추세를 보이고 있다. 북한의 석탄광상은 원생대로부터 신생대에 이르기까지 다양한 지질시대 지층에 배태되어 있으나, 가장 중요한 탄전지대는 평남분지 내에 분포하는 후기 고생대 퇴적층인 평안초군층의 립석주층 및 사동주층 함탄층이며, 이들은 평남북부탄전과 평남남부탄전을 이룬다. 북한 석탄의 약 90% 이상을 이 탄전에서 생산한다. 북한에서 석탄 분류는 탄화 정도에 따라 분류한 국제적 분류(토탄, 갈탄, 아역청탄, 역청탄과 무연탄)와는 다르게 산업적 견지에서 유연탄, 무연탄, 초무연탄으로 분류하고, 유연탄은 수탄(아갈탄), 갈탄, 역청탄으로 분류하며, 발열량 기준으로 고열탄, 보통탄, 저열탄으로 분류하기도 한다. 북한에서 지칭하는 초무연탄은 우리나라 뿐만 아니라 세계적으로도 분류되지 않은 석탄 등급이며, 북한에서만 유일하게 사용하고 있는 부니질 저급 석탄이다. 이 기고에서는 석탄의 국제적 분류와 북한 분류를 비교하고, 북한 석탄의 지질학적 부존특성 및 부존량, 활용분야 및 연구동향을 파악하여 북한 석탄 자원을 보다 정확하고 심도 깊게 이해할 수 있는 내용으로 구성하고자 하였다. 이 연구는 남북 광물자원 협력이 가시화 되었을 때 석탄과 관련된 과학적 및 산업적 협력 아젠다를 준비하는데 지침으로 활용 될 수 있을 것이다.

• Korean Chemical Engineering Research
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• 제52권6호
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• pp.796-806
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• 2014

석탄가스화를 기반으로 한 발전(IGCC 발전) 및 화학원료 제조공정의 상업화 관건은 화석연료인 원유 또는 천연가스를 기반으로 생산되는 경우와 비교하여 경제성을 확보할 수 있는지 여부이다. 경제성 확보를 위한 가장 현실적인 방법으로는 석탄 가스화를 통해 얻어진 합성가스로부터 2개 이상의 생산물(예: 발전과 화학원료를 동시 생산)을 병산(coproduction 또는 poly-generation)하는 것이다. 본 연구에서는 석탄 가스화를 기반으로 하여 발전과 수송용, 발전용 및 가정용 연료로 사용이 가능한 DME(dimethyl ether)를 병산하는 공정에 대한 경제성 분석을 실시하였다. 경제성 분석을 위한 병산 공정에서는 250 MW 전력생산 연간 30만 톤의 DMZ 생산을 기준으로 하였다. 병산 공정에서 DME 판매가격이 50만원/ton인 경우, 전기 생산원가는 34.8~58.4원/kWh으로 SMP(계통한계가격) 가중평균인 150.69원/kwh(2013년 1월~12월까지의 평균값)의 33~58% 수준으로 산정되었다. 따라서, DME 판매가격이 적정하게 유지될 경우 석탄 IGCC+DME 병산공정은 IGCC 단독 발전과 비교하여 경제성을 확보할 수 있을 것으로 판단된다. 현재 중국에서 DME 판매가격이 900,000원/톤 내외이므로, 전력과 DME를 병산할 경우, IGCC 단독으로 전력을 생산할 경우와 비교하여 전력 생산 원가를 월등하게 낮출 수 있음을 알 수 있다. 이와 같이 석탄 가스화를 기반으로 한 병산 공정을 통해 전력과 DME를 병산하는 시스템에서, 시장 여건에 따라 전력과 DME 생산비율 제어가 가능하고, 석탄 가스화기 및 정제 시스템을 공통 설비로 활용함으로써, 개별적으로 생산하는 것보다 생산 원가를 낮출 수 있다는 결과를 얻었다.

• 한국시스템다이내믹스연구
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• 제2권2호
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• pp.25-40
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• 2001

This paper describes the forecast of power plant construction in a competitive korean electricity market. In Korea, KEPCO (Korea Electric Power Corporation, fully controlled by government) was responsible for from the production of the electricity to the sale of electricity to customer. However, the generation part is separated from KEPCO and six generation companies were established for whole sale competition from April 1st, 2001. The generation companies consist of five fossil power companies and one nuclear power company in Korea at present time. Fossil power companies are scheduled to be sold to private companies including foreign investors. Nuclear power company is owned and controlled by government. The competition in generation market will start from 2003. ISO (Independence System Operator will purchase the electricity from the power exchange market. The market price is determined by the SMP(System Marginal Price) which is decided by the balance between demand and supply of electricity in power exchange market. Under this uncertain circumstance, the energy policy planners such as government are interested to the construction of the power plant in the future. These interests are accelerated due to the recent shortage of electricity supply in California. In the competitive market, investors are no longer interested in the investment for the capital intensive, long lead time generating technologies such as nuclear and coal plants. Large unclear and coal plants were no longer the top choices. Instead, investors in the competitive market are interested in smaller, more efficient, cheaper, cleaner technologies such as CCGT(Combined Cycle Gas Turbine). Electricity is treated as commodity in the competitive market. The investors behavior in the commodity market shows that the new investment decision is made when the market price exceeds the sum of capital cost and variable cost of the new facility and the existing facility utilization depends on the marginal cost of the facility. This investors behavior can be applied to the new investments for the power plant. Under these postulations, there is the potential for power plant construction to appear in waves causing alternating periods of over and under supply of electricity like commodity production or real estate production. A computer model was developed to sturdy the possibility that construction will appear in waves of boom and bust in Korean electricity market. This model was constructed using System Dynamics method pioneered by Forrester(MIT, 1961) and explained in recent text by Sternman (Business Dynamics, MIT, 2000) and the recent work by Andrew Ford(Energy Policy, 1999). This model was designed based on the Energy Policy results(Ford, 1999) with parameters for loads and resources in Korea. This Korea Market Model was developed and tested in a small scale project to demonstrate the usefulness of the System Dynamics approach. Korea electricity market is isolated and not allowed to import electricity from outsides. In this model, the base load such as unclear and large coal power plant are assumed to be user specified investment and only CCGT is selected for new investment by investors in the market. This model may be used to learn if government investment in new unclear plants could compensate for the unstable actions of private developers. This model can be used to test the policy focused on the role of unclear investments over time. This model also can be used to test whether the future power plant construction can meet the government targets for the mix of generating resources and to test whether to maintain stable price in the spot market.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.113.1-113.1
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• 2010

IGCC(Integrated Coal Gasification and Combined Cycle) plants can be among the most advanced and environmental systems for electric energy generation from various feed stocks and is becoming more and more popular in new power generation fields. In this work, the performance of IGCC plants employing Shell gasification technology and a GE 7FB gas turbine engine was simulated using IPSEpro open-equation modeling environment for different operating conditions. Performance analyses and comparisons of all operating cases were performed based on the design cases. Discussions were focused on gas composition, syngas production rate and overall performance. The validation of key steady-state performance values calculated from the process models were compared with values from the provided heat and material balances for Shell coal gasification technology. The key values included in the validation included the inlet coal flow rate; the mass flow rate, heating value, and composition of major gas species (CO, H2, CH4, H2O, CO2, H2S, N2, Ar) for the syngas exiting the gasifier island; and the HP and MP steam flows exiting the gasifier island.