CO2 capture from combined cycles integrated with Molten Carbonate Fuel Cells
CO2 capture from combined cycles integrated with Molten Carbonate Fuel Cells
复制标题
DOI：
10.1016/j.ijggc.2009.11.007
复制
发表时间：
2010-05
影响因子：
3.9
通讯作者：
S. Campanari;P. Chiesa;G. Manzolini
中科院分区：
文献类型：
--
作者：
S. Campanari;P. Chiesa;G. Manzolini
熔融碳酸盐燃料电池(MCFCs)在天然气联合循环中具有潜在的二氧化碳分离应用前景。MCFC在阳极侧通过CO32−离子对天然气进行电化学氧化，就碳捕获而言，这有两个好处：电池在阴极去除CO2Feed，以促进碳酸盐离子在电解液中的传输，并避免对氧化产物的任何稀释。MCFC可以“改装”成联合循环，使燃气轮机废气在进入热回收蒸汽发生器(HRSG)之前就有机会去除其中的大部分二氧化碳，并允许在高效的“混合”燃料电池+汽轮机配置中开发热回收蒸汽循环。用残渣纯氧燃烧、余热锅炉燃烧产物冷却、水分离后，可很容易地从电池阳极废气中回收二氧化碳。由此产生的动力循环有可能使整个循环的电效率与最初的联合循环基本保持不变，同时分离80%的以其他方式排放的二氧化碳，并限制燃料电池的尺寸，燃料电池约占总功率输出的17%，因此大部分功率容量依赖于传统的低成本涡轮机械。计算得到的二氧化碳比能量比常规燃烧后捕集技术的平均值低约4倍。灵敏度分析表明，积极的结果也明显改变了许多MCFC和工厂设计参数。
In this paper Molten Carbonate Fuel Cells (MCFCs) are considered for their potential application in carbon dioxide separation when integrated into natural gas fired combined cycles. The MCFC performs on the anode side an electrochemical oxidation of natural gas by means of CO32−ions which, as far as carbon capture is concerned, results in a twofold advantage: the cell removes CO2fed at the cathode to promote carbonate ion transport across the electrolyte and any dilution of the oxidized products is avoided. The MCFC can be “retrofitted” into a combined cycle, giving the opportunity to remove most of the CO2contained in the gas turbine exhaust gases before they enter the heat recovery steam generator (HRSG), and allowing to exploit the heat recovery steam cycle in an efficient “hybrid” fuel cell+steam turbine configuration. The carbon dioxide can be easily recovered from the cell anode exhaust after combustion with pure oxygen (supplied by an air separation unit) of the residual fuel, cooling of the combustion products in the HRSG and water separation. The resulting power cycle has the potential to keep the overall cycle electrical efficiency approximately unchanged with respect to the original combined cycle, while separating 80% of the CO2otherwise vented and limiting the size of the fuel cell, which contributes to about 17% of the total power output so that most of the power capacity relies on conventional low cost turbo-machinery. The calculated specific energy for CO2avoided is about 4 times lower than average values for conventional post-combustion capture technology. A sensitivity analysis shows that positive results hold also changing significantly a number of MCFC and plant design parameters.