Molten Carbonate Fuel Cells for Retrofitting Postcombustion CO2 Capture in Coal and Natural Gas Power Plants

Author(s):  
Maurizio Spinelli ◽  
Stefano Campanari ◽  
Stefano Consonni ◽  
Matteo C. Romano ◽  
Thomas Kreutz ◽  
...  

The state-of-the-art conventional technology for postcombustion capture of CO2 from fossil-fueled power plants is based on chemical solvents, which requires substantial energy consumption for regeneration. A promising alternative, available in the near future, is the application of molten carbonate fuel cells (MCFC) for CO2 separation from postcombustion flue gases. Previous studies related to this technology showed both high efficiency and high carbon capture rates, especially when the fuel cell is thermally integrated in the flue gas path of a natural gas-fired combined cycle or an integrated gasification combined cycle plant. This work compares the application of MCFC-based CO2 separation process to pulverized coal fired steam cycles (PCC) and natural gas combined cycles (NGCC) as a “retrofit” to the original power plant. Mass and energy balances are calculated through detailed models for both power plants, with fuel cell behavior simulated using a 0D model calibrated against manufacturers' specifications and based on experimental measurements, specifically carried out to support this study. The resulting analysis includes a comparison of the energy efficiency and CO2 separation efficiency as well as an economic comparison of the cost of CO2 avoided (CCA) under several economic scenarios. The proposed configurations reveal promising performance, exhibiting very competitive efficiency and economic metrics in comparison with conventional CO2 capture technologies. Application as a MCFC retrofit yields a very limited (<3%) decrease in efficiency for both power plants (PCC and NGCC), a strong reduction (>80%) in CO2 emission and a competitive cost for CO2 avoided (25–40 €/ton).

Author(s):  
Maurizio Spinelli ◽  
Stefano Campanari ◽  
Matteo C. Romano ◽  
Stefano Consonni ◽  
Thomas G. Kreutz ◽  
...  

The state-of-the-art conventional technology for post combustion capture of CO2 from fossil-fuelled power plants is based on chemical solvents, which requires substantial energy consumption for regeneration. Apromising alternative, available in the near future, is the application of Molten Carbonate Fuel Cells (MCFC) for CO2 separation from post-combustion flue gases. Previous studies related to this technology showed both high efficiency and high carbon capture rates, especially when the fuel cell is thermally integrated in the flue gas path of a natural gas-fired combined cycle or an integrated gasification combined cycle plant. This work compares the application of MCFC based CO2 separation process to pulverized coal fired steam cycles (PCC) and natural gas combined cycles (NGCC) as a ‘retrofit’ to the original power plant. Mass and energy balances are calculated through detailed models for both power plants, with fuel cell behaviour simulated using a 0D model calibrated against manufacturers’ specifications and based on experimental measurements, specifically carried out to support this study. The resulting analysis includes a comparison of the energy efficiency and CO2 separation efficiency as well as an economic comparison of the cost of CO2 avoided under several economic scenarios. The proposed configurations reveal promising performance, exhibiting very competitive efficiency and economic metrics in comparison with conventional CO2 capture technologies. Application as a MCFC retrofit yields a very limited (<3%) decrease in efficiency for both power plants (PCC and NGCC), a strong reduction (>80%) in CO2 emission and a competitive cost for CO2 avoided (25–40 €/ton).


Energies ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 543 ◽  
Author(s):  
Manuele Gatti ◽  
Emanuele Martelli ◽  
Daniele Di Bona ◽  
Marco Gabba ◽  
Roberto Scaccabarozzi ◽  
...  

The objective of this study is to assess the technical and economic potential of four alternative processes suitable for post-combustion CO2 capture from natural gas-fired power plants. These include: CO2 permeable membranes; molten carbonate fuel cells (MCFCs); pressurized CO2 absorption integrated with a multi-shaft gas turbine and heat recovery steam cycle; and supersonic flow-driven CO2 anti-sublimation and inertial separation. A common technical and economic framework is defined, and the performance and costs of the systems are evaluated based on process simulations and preliminary sizing. A state-of-the-art natural gas combined cycle (NGCC) without CO2 capture is taken as the reference case, whereas the same NGCC designed with CO2 capture (using chemical absorption with aqueous monoethanolamine solvent) is used as a base case. In an additional benchmarking case, the same NGCC is equipped with aqueous piperazine (PZ) CO2 absorption, to assess the techno-economic perspective of an advanced amine solvent. The comparison highlights that a combined cycle integrated with MCFCs looks the most attractive technology, both in terms of energy penalty and economics, i.e., CO2 avoided cost of 49 $/tCO2 avoided, and the specific primary energy consumption per unit of CO2 avoided (SPECCA) equal to 0.31 MJLHV/kgCO2 avoided. The second-best capture technology is PZ scrubbing (SPECCA = 2.73 MJLHV/kgCO2 avoided and cost of CO2 avoided = 68 $/tCO2 avoided), followed by the monoethanolamine (MEA) base case (SPECCA = 3.34 MJLHV/kgCO2 avoided and cost of CO2 avoided = 75 $/tCO2 avoided), and the supersonic flow driven CO2 anti-sublimation and inertial separation system and CO2 permeable membranes. The analysis shows that the integrated MCFC–NGCC systems allow the capture of CO2 with considerable reductions in energy penalty and costs.


Author(s):  
Suping Peng

AbstractCoal has been the main energy source in China for a long period. Therefore, the energy industry must improve coal power generation efficiency and achieve near-zero CO2 emissions. Integrated gasification fuel cell (IGFC) systems that combine coal gasification and high-temperature fuel cells, such as solid oxide fuel cells or molten carbonate fuel cells (MCFCs), are proving to be promising for efficient and clean power generation, compared with traditional coal-fired power plants. In 2017, with the support of National Key R&D Program of China, a consortium led by the China Energy Group and including 12 institutions was formed to develop the advanced IGFC technology with near-zero CO2 emissions. The objectives of this project include understanding the performance of an IGFC power generation system under different operating conditions, designing master system principles for engineering optimization, developing key technologies and intellectual property portfolios, setting up supply chains for key materials and equipment, and operating the first megawatt IGFC demonstration system with near-zero CO2 emission, in early 2022. In this paper, the main developments and projections pertaining to the IGFC project are highlighted.


Author(s):  
G. Manzolini ◽  
S. Campanari ◽  
P. Chiesa ◽  
A. Giannotti ◽  
P. Bedont ◽  
...  

This paper presents an analysis of advanced cycles with limited CO2 emissions based onthe integration of molten carbonate fuel cells (MCFCs) in natural gas fired combined cycles (NGCC) in order to efficiently capture CO2 from the exhaust of the gas turbine. In the proposed cycles, the gas turbine flue gases are used as cathode feeding for a MCFC, where CO2 is transferred from the cathode to anode side, concentrating the CO2 in the anode exhaust. At the anode side, the MCFCs are fed with natural gas, processed by an external reformer which is thermally integrated within the FC module; the corresponding CO2 production is completely concentrated at the anode. The resulting anode exhaust stream is then sent to a CO2 removal section which is based on a cryogenic CO2 removal process, based on internal or external refrigeration cycles, cooling the exhaust stream in the heat recovery steam generator and recycling residual fuel compounds to the power cycle. In all cases, a high purity CO2 stream is obtained after condensation of water and pumped in liquid form for subsequent storage. The possibility to arrange the MCFC section with different configurations and operating parameters of the fuel cell modules is investigated, and the option to include two fuel cell modules in series connection, with intermediate cooling of the cathode stream, in order to enhance the plant CO2 separation effectiveness, is also examined. The MCFC section behavior is simulated taking into account Ansaldo Fuel Cells experience and reference data based on a dedicated simulation tool. Detailed energy and material balances of the most promising cycle configurations are presented; fuel cell and conventional components’ working parameters are described and discussed, carrying out a sensitivity analysis on the fuel cell CO2 utilization factor. The plant shows the potential to achieve a CO2 avoided fraction approaching 70–80%, depending on the CO2 concentration limit at cathode outlet, with overall electric efficiency only 1–2% points lower than the reference combined cycle. The plant power output increases by over 40%, thanks to the contributions of the MCFC section which acts as an active CO2 concentrator, giving a potentially relevant advantage with respect to competitive carbon capture technologies.


2003 ◽  
Vol 125 (12) ◽  
pp. 42-44 ◽  
Author(s):  
Jeffrey Winters

This article focuses on coal mining that is incredibly disruptive, and coal is heavy and bulky, involving rumbling freight trains to transport it. The idea that fuel cells are every bit as clean as coal is dirty is just as widespread. Fuel cells, after all, take hydrogen and oxygen, and combine those elements to make electricity and water. The program, called the Clean Coal Technology Program, was, in part, an effort to promote commercial-scale integrated gasification combined-cycle (IGCC) coal power plants in the United States. Molten carbonate fuel cell stacks routinely weigh in at 250 kW. For the Wabash River demonstration, eight stacks will be combined for 2 MW. It will be the largest carbonate fuel cell power plant operating on coal in the world. FuelCell Energy has been planning for this sort of project for more than 20 years.


Author(s):  
Umberto Desideri

This paper presents the state of the art and the perspectives of the use of molten carbonate fuel cells with renewable energy sources. The molten carbonate fuel cell is the only technology that can use fuels containing carbon monoxide and carbon dioxide in the anode gas. It has been even shown in experimental tests in single cells that carbon monoxide can be considered as a fuel in this type of fuel cell. The fuels that can be used in MCFC are landfill gas, biogas from anaerobic digestion processes and syngas from gasification of biomass and waste. The commercial size of MCFC stacks (125 to 250 kW) is the right size for use with such fuels which are generally not available for power plants with output larger than some MW. All the above fuels are characterized by the presence of contaminants that need be removed before their use in the fuel cell. Among the contaminants hydrogen sulfide and chlorine compounds seem to cause the worst damage. To be used with such fuels, MCFC still need to be deeply investigated and duration tests are needed to determine the highest tolerable concentrations in the anode gases.


2020 ◽  
Vol 167 (6) ◽  
pp. 064505 ◽  
Author(s):  
Jonathan Rosen ◽  
Timothy Geary ◽  
Abdelkader Hilmi ◽  
Rodrigo Blanco-Gutierrez ◽  
Chao-Yi Yuh ◽  
...  

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