基于化学链制氧的富氧燃烧机组性能研究

发布时间：2018-03-11 10:49

  本文选题：化学链　切入点：模拟　出处：《东南大学》2015年硕士论文　论文类型：学位论文

【摘要】：化石能源开发利用过程中,大量排放出的CO2是最主要的温室气体。减排CO2已经成为化石能源利用的主要研究方向。化学链高温空分制氧技术作为一种新颖的制氧技术,能有效实现空气中氧气和氮气的分离,制取02/C02混合气,结合常规燃煤锅炉,能高效地实现二氧化碳的零排放。基于Aspen Plus软件,本文主要开展三方面工作：1)分别对化学链高温制氧流程、传统燃煤电厂热力系统和烟气冷却压缩流程进行模拟计算,并将上述三种流程进行集成。2)针对集成后的富氧燃烧系统进行过程分析与优化,找出最佳运行参数,考察其能耗和效率,并与传统燃煤电厂进行比较。3)基于将传统燃煤电厂改造为富氧燃烧系统中存在的局限性,本文结合化学链高温制氧流程的特点,设计出一种新型的富氧燃烧热力系统,对其性能及运行参数进行初步分析。基于新型化学链高温空分制氧(CLAS)技术,针对现有的1000MW常规燃煤机组进行改造,初步提出了一套改造方案。采用载氧体Mn3O4-Mn2O3,氧化反应器温度为787℃,还原反应器温度为762.4℃,制氧浓度为12.2%。排烟进过冷却压缩后,CO2浓度超过97%,可以用于大规模运输和储存,实现了碳零排放。CLAS富氧燃烧系统净效率38.92%,非常接近于常规电厂的净效率,仅低3.28%。对CLAS富氧燃烧系统的CLAS系统、发电燃烧系统和烟气冷却压缩系统进行耦合优化。采取优化措施后,CLAS富氧燃烧系统净效率可以提高1.52%,达到40.44%。考察了CLAS系统反应器温度、过量空气系数以及不同载氧体对CLAS富氧燃烧系统的影响,结果表明反应器温度为790℃(氧化反应器)、765℃(还原反应器),排烟含氧量为2%和以Mn3O4-Mn2O3为载氧体的系统性能较优。本文提出CLAS单压再热式富氧燃烧系统。模拟结果表明该系统的净效率为43.32%。通过对比其他二氧化碳捕集技术,如IGCC-CCS?传统低温空分制氧富氧燃烧技术等,CLAS单压再热富氧燃烧方式热利用率较高,热损失小。因此基于CLAS得单压再热式富氧燃烧电厂具有进一步研究和发展的潜力。
[Abstract]:During the development and utilization of fossil energy, the CO2 emitted from large quantities is the most important greenhouse gas. CO2 emission reduction has become the main research direction of fossil energy utilization. As a novel oxygen generation technology, the chemical chain high-temperature air separation technology is used to produce oxygen. It can effectively realize the separation of oxygen and nitrogen in the air, produce 0.2 / C02 mixture, and combine with conventional coal-fired boiler to achieve zero carbon dioxide emission efficiently. Based on Aspen Plus software, This paper mainly carries out three aspects of work: (1) to simulate the chemical chain high temperature oxygen production process, the traditional coal-fired power plant thermal system and the flue gas cooling compression process, respectively. The process analysis and optimization of the integrated oxygen-enriched combustion system are carried out to find out the best operation parameters, and to investigate the energy consumption and efficiency. Compared with traditional coal-fired power plant, based on the limitation of transforming traditional coal-fired power plant into oxygen-enriched combustion system, this paper designs a new oxygen-enriched combustion thermodynamic system based on the characteristics of chemical chain high-temperature oxygen production process. On the basis of the new chemical chain high temperature air separation oxygen production process (CLASS) technology, the existing 1000MW conventional coal-fired units were retrofitted. A set of retrofit scheme was put forward. The oxygen carrier Mn3O4-Mn2O3 was used, the temperature of oxidation reactor was 787 鈩，

本文编号：1597837