Pyrolyzed Fuel Oil/Coal-tar 혼합원료의 열중합 반응에 따른 Pitch 제조 특성

이은별 ( Eunbyul Lee ),김형기 ( Hyeong Gi Kim ) 한국공업화학회 2020 공업화학 Vol.31 No.3

본 연구에서는 PFO와 Coal-tar의 구조와 열 중합 거동 분석을 통해 PFO와 Coal-tar으로 구성된 혼합 원료의 피치 합성 간 제조 특성을 확인하였다. 원소분석과 FT-IR 분석을 통해, PFO와 Coal-tar 각각 0.355, 0.818로 방향족화도 수치를 확인하였다. 또한, PFO와 Coal-tar의 열중량 분석을 통해 질량 감소곡선의 차이를 확인하였으며, 이러한 현상은 방향족 화도와 관능기 함량에 따른 구조적 안정성에 기인한 것으로 판단된다. 피치 제조 특성은 PFO를 원료로 사용한 피치가 혼합원료로부터 제조된 피치보다 평균적으로 낮은 수율과 높은 연화점을 보임을 확인하였다. 특히 유사한 연화점을 가지는 P360 (138.5 ℃)과 B420 (141.4 ℃)을 비교하였을 때, 두 피치의 탄화수율은 각각 29.89, 49.03 wt%로 Coal-tar가 혼합된 경우 약 20 wt% 향상됨을 확인하였다. 이러한 결과는 다량의 알킬기를 포함하여 높은 피치 중합 반응성을 가지는 PFO와 높은 열적 안정성을 가지는 Coal-tar의 혼합에 기인한 것으로 판단된다. In this study, blended feedstock derived pyrolyzed fuel oil (PFO) and coal-tar was prepared to produce a pitch by thermal polymerization reaction for manufacturing artificial graphite materials. The aromaticity value of 0.355 and 0.818 was obtained for PFO and coal-tar, respectively. In addition, PFO and coal-tar exhibited the difference tendency of weight loss curve for thermogravimetric analysis, which is related to the structural stability depending on the aromaticity and functional groups. The production characteristics confirmed that the pitch derived PFO showed lower production yield and higher softening point than that using blended feedstock. In particular, when comparing P360 (138.5 ℃) and B420 (141.4 ℃) having similar softening points, the production yields of both pitches exhibited 29.89 and 49.03 wt%, respectively. This is mainly due to the blending of PFO and coal-tar having high pitch polymerization reactivity including a large amount of alkyl groups and coal-tar having high thermal stability. This phenomenon indicated that the increased production yield is because of a synergic effect of both the high reactivity of PFO and thermal stability of coal-tar.

에너지자원의 환경관리전략 : 화력발전소 회처리에 따른 환경영향 최소화방안 연구(2)

맹준호,김태윤,조한나,김은영 한국환경정책평가연구원 2015 사업보고서 Vol.2015 No.-

석탄화력발전소에서 매년 석탄회가 배출되고 배출량의 일부를 재활용하고 남은 석탄회는 회처리장에 매립되어 처리되고 있다. 현재 회처리장 용량에는 한계가 있고, 석탄회매립으로 인한 환경영향의 우려로 회처리장 신규 확보도 어려운 상황이어서, 환경영향 최소화라는 측면에서 석탄회 재활용 및 유효이용이 향후 장기적·국가적으로 시급하게 해결해야 할 문제로 인식되고 있다. 이러한 문제 인식에 토대하여 본 연구에서는 국내에서 적용 가능한 대규모 석탄회 유효이용의 확대방안으로 해안개발 및 연안재생사업과 광해복구사업의 석탄회 유효이용 및 환경관리방안을 제시하였다. 그리고 국내 석탄회 재활용확대를 가로막고 있는 문제점을 분석하여 친환경적 국토관리와 자원순환사회를 위한 석탄회 재활용 개선방안을 제안하였다. 대규모 석탄회 유효이용방안인 해안개발 및 연안재생사업은 국내 적용 시 현재 동해안에 운영 예정이거나 계획 중인 석탄화력 발전소 인접지역의 해안사업지에서 석탄회 재활용을 높이는 것이 바람직하다. 더불어 석탄회 혼합재료를 활용한 해양구조물에 대한 환경안전품질 기준을 수립하여 석탄회 유효이용 및 재활용 분야를 다변화할 필요가 있다. 석탄회를 이용한 연안재생사업은 우선적으로 지속적인 관리 및 모니터링이 용이한 발전소 호안을 대상지로 선정하는 것이 바람직하며, 지속적인 모니터링과 그 결과를 바탕으로 초기계획타당성 검증 및 관리계획을 지속적으로 수정·보완하는 과정을 거쳐 환경관리방안을 수립하는 것이 필요하다. 석탄회를 이용한 광해복구사업은 환경적으로 검증할 수 있는 용출방법 및 기준 마련이 요구되며, 석탄회에 따른 환경적인 영향을 파악하기 위해서 지하수 및 지표수의 수질,광산의 지반 형태 및 지각 특성, 대상지 현장 pH를 조사하여야 한다. 석탄회를 활용할 경우 가장 우려되는 부분은 석탄회로부터의 용출이며, 실제로 적용 시 발생하는 현상은 다양하고 복잡하기 때문에 석탄회 충전 후 지하수와 지표수의 흐름을 반영한 모니터링지점, 주기, 항목을 지정하여 필수적으로 실시해야 한다. 본 연구는 석탄회를 이용한 광해복구사업의 추진에 있어 석탄회 검증 및 석탄회 재활용 대상지의 적합성 여부를 파악하고, 최상의 안전성 확보방안으로 사후모니터링을 통해 환경성을 검증하는 친환경적인 관리체계를 제시하였다. 석탄회 유효이용 및 재활용 확대를 위한 제도적 방안으로 접촉매체(토양, 지하수, 지표수, 해수)에 따른 지침개발이 필요하며, 환경성 검토 내에 사후관리 규정을 포함하여 시행하는 것이 바람직하다. 환경성 검토, 작성, 협의, 검토 등의 과정에서 이·화학적 재활용기준 제정이 필요하며, 특히 석탄회 재활용 용도별 기준을 제정하여 환경성과 경제성을 동시에 충족할 수 있는 기준 제정이 요구된다. 석탄회 재활용 사업 시 환경단체, 주민, 이해관계자 등은 석탄회가 환경적으로 안전하지 않다는 인식으로 인해 빈번하게 갈등을 겪고 있다. 이에 연구기관, 정부기관, 발전사 등은 석탄회의 환경적 안전성에 관한 홍보 및 석탄회 위해성에 대한 다양한 연구를 진행하는 등 지속적인 노력을 해야하며, 재활용 시 접촉되는 매체에 따른 용출 특성에 관한 연구를 통해 재활용 수요처의 다양성 확대를 유도할 필요가 있다. 또한 기존의 석탄회 재활용사례에 대한 사후모니터링을 실시하여 석탄회 재활용이 환경적으로 안전하다는 인식을 우선적으로 규명해야 할 것이며, 사업진행 시에는 계획 수립단계의 투명성을 확보하고, 지역사회와의 적극적인 의사소통 및 정보제공을 통해 갈등을 해결하도록 노력하여야 한다. 발전사는 석탄회 재활용 확대를 위해 배출사업자 입장에서 오염자 부담원칙에 의거하여 석탄회에 대한 연구개발 및 홍보 등 환경적 무해성을 입증할 직접적인 책임이 있다. 현재진행되고 있는 환경적 안전성 검사의 결과정보가 지속적으로 공개되지 않고 있으므로 환경적으로 안전하다는 검사결과를 통해 석탄회의 안전성을 홍보하는 것이 필요하다. 또한 발전사는 석탄회 환경적 안전성 검사 시 석탄회 발생출처에 관한 상세한 이력을 공개하여 석탄회 재활용 용도분야를 확보하고 안전한 절차관리를 책임질 필요가 있다. Coal ash is generated from coal-fired thermal power plants every year. Except for the recycled portion, the remaining quantity of coal ash ends up in landfills. As the current ash pond capacity is limited and ash treatment system differ from plant to plant, most of the employed methods seem almost barbaric. Currently, the difficulties faced in building a new ash treatment plant are attributed to the concerns raised over the environmental impacts of landfills at individual plant facilities. In terms of minimizing environmental impact, the recycling and effective use of coal ash are recognized as urgent issues to tackle. In response to these needs, this study proposes coastal development, coastal regeneration projects and mine reclamation projects as the solution for expanding the effective uses of coal ash. Additionally, the obstacles in expanding the recycling of coal ash in South Korea are analyzed and solutions are proposed. In the study, coastal development, coastal regeneration projects and mine reclamation projects are proposed as effective use of coal ash in large scale. In case coastal development and coastal regeneration projects are carried out in South Korea, it is better to improve the recycling rate of coal ash in coastal sites that are adjacent to coal-fired thermal power plants whose operation or establishment is planned. In addition, the environmental safety quality standar ds for marine structures (that utilize coal ash mixed materials) must be establish ed to diversify the effective use and recycling of coal ash. In coastal regeneration projects that use coal ash, it is preferable to select a revetment which allows consistent management and monitoring as the target area. Based on continuous monitoring and their results, an environmental management plan should be established by verifying the feasibility of the initial plan and consistently modif ying and supplementing the management plan. In case of mine reclamation projects, the flow out method and standards should be formulated and the quality of ground and surface water, soil types of mines and pH must be investigated in order to identify the possible environ mental impact of coal ash. After the filling of coal ash, monitoring which reflects the flow of ground and surface water must be carried out by defining the monitoring points, monitoring cycle and monitored items. For mine reclamation projects that use coal ash, the study proposes to verify the coal ash, confirm the suitability of target area as coal ash recycling site and presents an environme ntally friendly management system through post EIA. In terms of the institution al approach in improving the effective use and recycling of coal ash, guideline needs to be developed according to the type of contact media (soil, ground water, surface water, sea water). In addition, it is advisable to conduct environ mental review by including post EIA regulations, define the criteria of recycling during the environmental review, report formulation, consultation and review processes and establish coal ash recycling criteria by use. Research institutions, government agencies, and power companies must exert efforts to promote the environmental safety of coal ash and conduct a wide range of studies on the hazard of coal ash. In addition, the perception of coal ash recycling as an environmental safe method must be established by monitori ng the existing cases of coal ash recycling. During projects, transparency must be ensured in the planning stage and conflicts with the local community must be resolved through active communication and provision of information. Power companies have a direct responsibility to prove the environmental har mlessness of coal ash through R&D and PR.

Research and Design of Coal PLC Control System in Coal-fired Power Plants

Yuheng Yin,Zhongzhe Yue 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.1

Coal handling system in thermal power plant is the important component of the auxiliary system of power plant, it takes on the power plant's power to produce fuel supply missions with other corresponding mechanical and electrical equipments. During the operation of thermal power plants, the improvement of working efficiency of coal handling system is the key factor to improve the work efficiency of the whole power plant, the whole process of remote monitoring of coal is also put forward higher requirements on the design of automatic control system, so we choose the most widely used PLC control system in coal handling system, it makes the dream a reality.

최근 3년간 수입 유연탄 분석 및 연소열성능 해석을 활용한 석탄화력 발전소 탄종 경제성 평가 연구

백세현(Sehyun Baek),박호영(Hoyoung Park),고성호(SungHo Ko) 한국연소학회 2013 한국연소학회지 Vol.18 No.3

In this study, the economic evaluation for imported coals was conducted for power plant based on thermodynamical performance analysis. The number of coal types considered was 1,755 imported by five power generation companies in Korea during the 2010-2012. The higher heating value (HHV) of the coals ranged 4,000-6,500 kcal/kg, mostly sub-bituminous. The 1D thermo-dynamical performance modeling was performed for a 500 MWe standard power plant using PROATES code. It was founded that the low rank coals had negative effects on the plant efficiency mainly due to the increased heat loss by moisture, hydrogen and flue gas. Based on the performance analysis, the economic performance of the coals was evaluated. The apparent price of low-rank coals tended to be significantly lower than design coal; for example, the unit price of coal with a HHV of 4,000 kcal/kg was 57% of the reference coal having 6,080 kcal/kg. Considering the negative effects leading to a decrease in the thermal performance, heating value compensation, and increased parasite load, the corrected unit cost for the coal with 4,000 kcal/kg was 90.7% of the reference coal. Overall, the cost saving by imported coals was not high as expected.

Behavior of mercury release during thermal decomposition of coals

Shaoqing Guo,Yong Xiao,Jianli Yang,Zhenyu Liu 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.2

The mercury release behavior during thermal decomposition of three Chinese coals with different types was studied under nitrogen, carbon dioxide and air at temperatures of 800, 900, 1,000 and 1,100℃. The thermal treatment experiments were carried out in a quartz tube reactor. Results showed that the release ratio of total mercury during thermal decomposition of coals increases with the increasing temperature. The order of the amount of mercury released under the three atmospheres is nitrogen<carbon dioxide<air for all three coals during thermal decomposition. This indicates that air and carbon dioxide can promote the mercury release due to their reactivity with coal. However, the order of amount of elemental mercury released under the three atmospheres is nitrogen>carbon dioxide>air for all three coals. The release behavior of the total mercury under air is independent of the coal type. Under the other two atmospheres the release behavior is distinguished by the coal type.

화력발전소 회처리장 조성에 따른 환경영향 최소화를 위한 석탄회 재활용 확대방안에 관한 연구

서동환 ( Dong Hwan Suh ),맹준호 ( Jun Ho Maeng ) 한국환경영향평가학회 2015 환경영향평가 Vol.24 No.5

More than 8M tons of coal ashes are generated from coal-fired thermal power plants every year in Korea. Excluding the recycled portion (Current recycling rate: approximately 70%), all of the generated coal ashes end up in coastal landfills. Currently, the difficulties faced in establishing new ash treatment fields are attributed to the concerns raised over the environmental impacts caused by the landfills at individual plant facilities. Given the number of coal-fired thermal power plants to be built in the future (reflected in the 7th Basic Plan for Long-term Electricity Supply and Demand), building new ash treatment fields or seeking a new treatment plan seems unavoidable. Based upon a review of coal ash and its management, this study concluded that the most effective and fundamental strategy to minimize the environmental impacts resulting from coal ash landfills is to avoid constructing new coal-fired powerplants and furthermore, suggests that the practice of beneficial use and recycling the produced coal wastes should be encouraged.

The relationship between the molecular composition of coal and the conversion of its organic matter during thermal dissolution

Safin V. A.,Kuznetsov P. N.,Avid B.,Kuznetsova L. I.,Fan Xing,Ismagilov Z. R. 한국탄소학회 2022 Carbon Letters Vol.32 No.4

The team has studied the relationship between the ability of the coals to be dissolved in crude anthracene oil and their composition. The coal samples taken from different deposits in Russia and Mongolia were characterized by different stages of metamorphism and tested by the Fourier transform infrared spectroscopy and Carbon-13 nuclear magnetic resonance. The data of a correlation analysis enabled us to find out that an amount of aromatic structures in coal macromolecules provided the main influence on the thermal dissolution of the coals. The middle-rank coals had the highest rates of coal organic matter transfer to liquid products. The data showed that the dissolution process was accompanied by destruction of weak bonds among aliphatic groups. The amount of methylene groups in the aliphatic part of coal macromolecules had a direct impact on conversion of the coal organic matter into soluble products.

Preparation of tungsten carbide from mixtures of natural wolframite and carbon-containing solid fuels with assistance of mechanical activation

L.Telmenbayar,J. Temuujin 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.5

Mechanically milled mixtures of wolframite and coke, coking coal or thermal coal have been characterized with DTA-TG,XRD and SEM techniques. Mixtures were milled with a planetary ball mill for 4 h and heated at 1000 oC or 1100 oC for 1 hrunder argon gas. The mixtures with coke and coking coal contained WC and Fe3W3C whilst the mixture with thermal coalconsisted of only Fe3W3C phase even after 1 hr calcination at 1100 oC. The amount of WC in the product from coke was higherthan with coking coal. Thermal coal was not a suitable carbon source for forming WC by this route. Coke is considered themost preferable carbon source on preparation of WC in the carbothermic reduction of the wolframite

An Exploratory Study of Material Flow Cost Accounting: A Case of Coal-Fired Thermal Power Plants in Vietnam

To Tam NGUYEN 한국유통과학회 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.5

The purpose of this paper is to examine the use of material flow cost accounting (MFCA) in Vietnam’s coal-fired thermal power plants. This study is based on the contingency and system theories to explain the application of management tools and analyze steps of input, output, and process in manufacturing. Costs in producing process-based MFCA include material cost, energy cost, system cost, and waste management cost. The exploratory case study methodology is used to describe and answer two questions, namely “How coal flow cost is recognized?” and “Why waste in material consumption can be harmful to the environment?”. By analyzing the Quang Ninh and Pha Lai coal-fired thermal power plants that are the typical plants, this paper identifies the flow of primary material in these plants as a basis for determining losses for the business. The material flow of coal-fired thermal power plants provides the basis for the use of the MFCA. The manufacturing of electrical items in these plants is divided into four stages, each with its own set of losses. As a result, some phases in the application of MFCA are suggested, as well as some other elements required for MFCA application in coal-fired thermal power plants.

저급석탄 사용 가능 이중 선회형 컴팩트 석탄가스화기의 열응력 평가

김슬찬(Seul-Chan Kim),박창용(Chang-Young Park),정웅락(Ung-Rak Jeong),유승현(Seung-Hyun Yoo) (사)한국CDE학회 2011 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2011 No.1

Coal is being used for power generation but there are many applications if coal became gas. Core technology of Coal gasification technology is gasifier technology. Double swirler compact gasifier using low rank coal is developed to make alternative fuel materials. Developing gasifier is composed four parts cap section, middle section, gasifier section and quencher. Synthesis gas(CO+H2)is made in gasifier using low rank coal. Gasifier section internal maximum temperature is 1500℃ and internal maximum pressure is 20 atm. Gasifier section experience thermal stresses and significant dimensional changes by internal high temperature. In this paper, full scale finite element analysis of casifier section was carried out in high temperature and high pressure conditions to examine structural safety.