【作者】 刘晓；

【导师】 韩吉田；

【作者基本信息】 山东大学 ， 动力工程（专业学位）， 2018， 硕士

【摘要】 作为一种高效、低排放的电化学发电装置,固体氧化物燃料电池(Solidoxide fuel cell,SOFC)对解决全球能源危机与环境污染问题具有重要意义。它不仅具有发电效率高、余热利用价值高、燃料种类丰富、污染物排放少以及易于C02的富集与分离等优点,还可应用于天然气发电和洁净煤发电技术,也特别适合与燃气轮机(Gas turbine,GT)构成高效清洁的SOFC/GT混合发电系统。SOFC/GT作为实现Vision 21计划目标的关键技术之一,其排放的尾气仍具较高的余热利用价值。因此,通过引入余热锅炉-蒸汽轮机系统(Heat recovery steam generator-Steam turbine,HRSG-ST)对SOFC/GT系统尾气进行余热利用,可以有效提高整个系统的能源利用效率,具有重要的理论意义和工程应用价值。压缩空气储能(Compressed air energy storage,CAES)技术可有效解决间歇性可再生能源发电并网难和低谷电能得不到充分利用等问题。为了保证SOFC/GT的稳定可靠运行,有效避免在变负荷运行时由于系统参数变化导致的材料热应力变化等问题对SOFC/GT系统的稳定可靠性造成不利影响,论文通过将CAES和C02捕集系统引入SOFC/GT而构成了一种具有C02捕集(Carbon Capture and Storage,CCS)的SOFC/GT与压缩空气储能混合发电系统。该系统可充分发挥SOFC/GT发电系统的高效、清洁与CAES的削峰填谷、负荷跟踪等优点,可有效保障整个混合发电系统的安全可靠稳定运行。本文主要研究内容:1.通过Aspen Plus软件对管式固体氧化物燃料电池进行建模和模拟研究,并将模拟结果与参考文献中的实验数据对比分析,验证该SOFC模型的准确可靠性,为整个混合发电系统的模拟研究创造条件。2.基于Huntorf的CAES电站运行参数,通过Aspen Plus分别建立典型CAES系统、带回热器的CAES系统和AA-CAES系统的模型,在保持系统设备和工质初始参数不变的情况下,研究不同CAES系统的性能参数,通过分析对比选择适合与SOFC/GT混合发电集成的压缩空气储能系统。3.建立1MW级的SOFC/GT/ST零排放混合发电系统模型,模拟计算系统状态参数和系统性能,并分别研究SOFC的运行压力、燃料利用率、蒸汽碳比以及电流密度等参数变化对系统性能的影响,以便确定混合发电系统的最优运行参数。4.基于南京某高校校区的日用电负荷变化情况,针对该校区设计并建立具有C02捕集的SOFC/GT和CAES混合发电系统。根据负荷的变化,进行各个动力设备的负荷分配,使系统能够逐时跟踪负荷变化并满足负荷需求。在此基础上,分析并比较四个不同配置的混合发电系统的性能参数,研究CAES和CCS的引入对整个混合发电系统性能的影响。通过上述研究,论文得到了如下主要结论:1.SOFC模型的模拟结果准确可靠,可以满足SOFC本体模拟要求,为混合发电系统的模拟计算提供了基础;2.三代CAES系统中,带回热的CAES系统输出功率高,且储能效率高于传统CAES系统,更适合与SOFC/GT进行耦合集成,可在较宽负荷变化范围内稳定可靠的运行,为后续SOFC/GT和CAES混合发电系统的研究提供了基础;3.构建的1MW级C02近零排放的SOFC/GT/ST混合发电系统的发电效率可高达73.5%,提高SOFC的工作压力、燃料利用率以及减小电流密度有助于提高整个混合发电系统的发电功率与效率;4.构建的具有C02捕集的SOFC/GT和压缩空气储能的混合发电系统,有效提高了整个系统的能源综合利用效率和大范围变负荷运行的安全可靠性,并实现了 C02的有效捕集,具有高效、运行安全可靠和环境友好等优点。更多还原

【Abstract】 As an efficient and clean electrochemical power generator,Solid oxide fuel cell(SOFC)is of great significance to solve the global energy crisis and environmental pollution issues.SOFC not only has advantages such as high power generation efficiency,multiple-fuel feeding,high utility value of waste heat,easy to enrich and separate carbon dioxide,but also is suitable to construct a highly efficient and clean SOFC/GT hybrid power system with the Gas turbine(GT).The SOFC/GT hybrid system is regarded as one of the key technologies to achieve the aim of Vision 21,and the exhaust gas of the system has a high utility value of waste heat.Thus,the overall energy utilization efficiency of the entire system would be improved by adding a heat recovery steam generator-Steam turbine(HRSG-ST)system to recover the waste heat,and there is an important theoretical significance and engineering application value.Compressed air energy storage(CAES)system plays an important role in solving the grid connection problem of intermittent renewable energy generation.To ensure the stable and reliable operation of the SOFC/GT hybrid system and avoid the problems such as the impact of the stress change of materials on the stable and reliable operation of the system because of the variable parameters of the system during the variable load operation period.The CAES and Carbon Capture and Storage(CCS)systems are added to the SOFC/GT hybrid system and a novel SOFC/GT hybrid power generation system with CO2 capture and compressed air energy storage is conducted in this thesis.The novel system can realize clean and high efficiency of the SOFC/GT hybrid power generation system and the advantages such as power peak load shifting and load following of the CAES system,and the safe,reliable and stable operation of entire hybrid power generation system could be guaranteed.The main research contents of this thesis are as follows:1.Aspen Plus software is used to model and simulate the tubular solid oxide fuel cell.The results of simulation are compared with the experimental data in references,which verify that the SOFC model is accurate and reliable to simulate the hybrid system.2.Based on the operating parameters of the Huntorf CAES power plant,models of a typical CAES system,a CAES system with a regenerator and an AA-CAES system are developed by using Aspen Plus software respectively.While maintaining the initial parameters of equipment and the working medium in the system unchanged,the performance of different CAES systems is analyzed and compared to select a compressed air energy storage system suitable for integration with SOFC.3.The model,1MW SOFC/GT/ST zero-emission hybrid power system,is simulated to calculate the parameters of each state point of the system.Besides,by studying the impact of changes in operating pressure,fuel efficiency,steam-to-carbon ratio and current density of the SOFC on the system performance,the appropriate operating parameters could be found to optimize the system operation.4.Based on the trend of daily electrical load of a university campus in Nanjing,a SOFC/CAES hybrid power generation system with CO2 capture and compressed air energy storage is designed and established for the campus.According to the load trend,the output power would be distributed to each power equipment,thus the system can meet the load demand hourly when tracking the load changes.Then,by analyzing and comparing the performance of four different hybrid power generation systems,the impact of CAES and CCS on the system performance of the entire system is studied.According to the research content of this thesis,the main conclusions can be summarized as follows:1.The simulation results of the SOFC model are reliable,which can satisfy the requirements to simulate the SOFC stack.The results provide bases for the simulation of the hybrid power generation system.2.In the three kinds of CAES systems,the system with regenerator has more power output than others,whose efficiency of energy storage is higher than that of the traditional CAES system.The system with regenerator is more suitable to be integrated with SOFC/GT and can operate stably and safely in a wide range of load variations.The results provide research bases for further study of the hybrid power generation system based on SOFC/GT and CAES.3.The power generation efficiency of the integrated 1MW CO2 near-zero-emission SOFC/GT/ST hybrid power system can reach up to 73.5%.The power generation efficiency would be improved by increasing the SOFC operating pressure and the fuel utilization and decreasing the current density.4.Compared with the former system,the overall energy efficiency,the safety and reliability of large-scale variable load operation of the constructed SOFC/GT hybrid power generation system with CO2 capture and compressed air energy storage is improved significantly.Meanwhile,the CO2 is captured effectively and this system has the advantages of high efficiency,safe and reliable operation and environmental friendliness.更多还原