| 摘要: | 本研究旨在研究質子陶瓷燃料電池 (PCFC) 與微型燃氣輪機 (MGT) 和有機朗肯循環 (ORC) 混合系統相結合，外部重整器由各種燃料提供燃料。 本研究使用乙醇、甲醇、氨、丙烷和辛烷分析了五種優化系統配置。 燃料類型的選擇是根據其重整溫度級別確定的。 每個優化系統配置的想法主要集中在煙道氣利用作為重整器組件的主要熱源，因此可以優化氫氣生產。 熱電聯產 (CHP) 系統在本研究中也作為系統靈活性的代表進行了評估。 接下來，還分析了空氣和燃料流量、燃料利用率 (Uf) 和陽極廢氣再循環率 (AOGR) 等幾個參數。 Thermolib 用於使用從參考文獻中獲得的輸入參數構建系統。
與其他配置相比，氨系統（配置 3）的結果顯示出最出色的系統性能。 達到的最大系統能量和㶲效率分別為 81.44% 和 77.24%，總㶲損失為 36.62 kW，這是最低的㶲損失百分比，從初始㶲輸入開始，整個循環中只有 22.76% 的㶲被破壞。 事實證明，熱電聯產系統可以將氨系統的整體系統能效提高高達 85.55%。 同時，與 ORC 系統相比，使用 CHP 系統的所有系統配置的㶲效率往往降低 2%。 氨系統熱回收蒸汽產生器（HRSG）的㶲效率最高可達68.5%。
參數變化結果表明，當 AOGR 比增加時，PCFC 功率輸出也會增加。 它從根本上與流入陽極的大量氫氣有關。 相反，當渦輪進口溫度和燃燒室反應物降低時，相應地降低 GT 功率輸出。 結果表明，與燃料電池功率的增加相比，GT 功率的減少相對較小； 因此，系統效率隨著 AOGR 比率的增加而增加。 此外，安裝 AOGR 可以使 PCFC-MGT-ORC 混合系統在各種 Uf 變化下以最大功率工作。
對 Uf 變化的研究表明，該參數對於 PCFC、MGT 和 ORC 的能量分配至關重要，其中電池功率輸出增加，但 MGT 功率輸出隨著 Uf 的增加而下降。 結果還表明，混合 PCFC-MGT-ORC 系統可以在具有高 AOGR 率的低 Uf 下產生最大功率，而混合系統可以在沒有 AOGR 的情況下在高 Uf 下產生峰值功率。
這項工作通過 (i) 確定使用各種燃料的 PCFC-MGT-ORC 混合系統中的適當配置，(ii) 了解基於熱量或電力需求的系統靈活性，(iii) 了解陽極關閉的影響，使科學界能夠 氣體再循環 (AOGR) 對系統性能的影響，以及 (iv) 選擇合理的燃料、S/C、Uf、空氣流量、燃料流量。
;This study aims to investigate protonic ceramic fuel cell (PCFC) combined with micro gas turbine (MGT) and Organic Rankine Cycle (ORC) hybrid systems with external reformer fueled by various fuels. Five optimized system configuration has analyzed in this study using ethanol, methanol, ammonia, propane, and octane. The fuel type selection was determined based on its reforming temperature level. The idea of each optimized system configuration is mainly focus on flue gas utilization as primary heat source for reformer component so the hydrogen production can be optimized. The combine heat and power (CHP) system is also been evaluated in present study as the representation of system flexibility. Next, several parameters such as air and fuel flow rate, fuel utilization factor (Uf), and anode off-gas recycling ratio (AOGR) are also analyzed. Thermolib is employed to build the system with input parameters obtained from references.
The results in ammonia system (configuration 3) show most outstanding system performance compared with other configuration. The maximum system energy and exergy efficiency achieved is 81.44% and 77.24%, respectively with a total exergy destruction of 36.62 kW which is the lowest exergy destruction percentage, with only 22.76% of exergy destroyed across the whole cycle from its initial exergy input. The CHP system proven can enhanced the overall system energy efficiency for up to 85.55% for ammonia system. Meanwhile, the exergy efficiency tends to decrease by 2% for all system configuration using CHP system compared with ORC system. The ammonia system heat recovery steam generator (HRSG) exergy efficiency is the highest up to 68.5%.
The parameter variation results reveal that when the AOGR ratio increases, so does the PCFC power output. It is fundamentally related to massive hydrogen flowing into the anode. In contrast, when turbine inlet temperature and combustor reactant decrease, correspondingly decreases MGT power output. The results indicate that the increase in fuel cell power is dominant than the decrease of MGT power; hence, system efficiency increases as the AOGR ratio grows. Furthermore, installing AOGR can keep a PCFC-MGT-ORC hybrid system working at maximum power under various Uf variations.
The investigation of Uf variations reveals that this parameter is critical in energy distribution into PCFC, MGT, and ORC, in which cell power output increases but MGT power output drops as Uf increases. The results also show that a hybrid PCFC-MGT-ORC system can generate maximum power at low Uf with a high AOGR rate, and a hybrid system can produce peak power at high Uf without AOGR.
This work enables the scientific community by (i) determining an appropriate configuration in a PCFC-MGT-ORC hybrid system using various fuels, (ii) understanding system flexibility based on heat or power demand, (iii) understanding the effect of anode-off gas recycling (AOGR) on system performance, and (iv) selecting a reasonable fuel, S/C, Uf, air flow rate, fuel flow rate. |
