基于氧解耦煤化学链气化的新型低碳发电系统质量／能量深度协同与优化

At present, Coal fired plant or coal gasification power plant pays much energy penalty and the cost of oxygen preparation for CO2 capture. Coal chemical looping gasification divides the traditional coal gasification reaction into two steps, which reduces the irreversible exergy loss in the combustion process and realizes fuel energy cascaded utilization, and averts the expensive investment and energy consumption of oxygen preparation. Besides, the composition of coal gasified gas can be adjusted orientedly and controlled in the coal chemical looping gasification process by adjusting the gasification parameters and conditions (such as temperature, pressure, gasification agent and oxygen carrier, etc.), which is beneficial to restraining CO2 formation. All those advantages of coal chemical looping gasification mentioned above will realize low cost, low energy penalty and low carbon emission conversion of coal from source. .This project will investigate the effective coupling of low carbon emission power system, which combines coal chemical looping gasification technology with methods of CO2 reduction and control. It is an interdisciplinary investigation, involving coal chemical engineering, chemical system engineering and engineering thermophysics. Although coal chemical looping gasification-based power system provides a technical platform for synergistic reduction and control of CO2 emissions, it changes the system matching manners of skills and techniques due to the redistribution of energy flow and substances flow from the coal chemical looping gasification process. Understanding the interaction mechanism amongst these functional units and integrating them via system optimization is pivotal for developing efficient, clean, and economical coal-to-electricity technologies. .A design theory and method for oxygen carrier will be investigated aiming to proactive control composition and quality of coal gasified gas, and the evolution law of C element and the regulation mechanism of components in coal chemical looping gasification under the complex atmosphere will also be disclosed. Furthermore, by explaining the rules of conversion, transfer, and enrichment of Cx-containing components in different coal chemical looping gasification-based power system, the coupling principle of cascaded utilization of chemical and physical energy, CO2 separation and recycle will be revealed. Finally, we will establish an integration theory and method for coal chemical looping gasification-based power system integrated with CO2 control, in which energy, environmental impact, and economics are inherently linked. All those studies will help to save coal and water, increases economic profits and reduces CO2 emission of the whole production process of a coal chemical looping gasification-based power plant.

现有燃煤发电/煤气化发电-捕集CO2技术，由于烟气CO2浓度低或需要纯氧作为气化剂，需要付出巨大的捕集能耗和昂贵的制氧成本。煤化学链气化技术利用载氧体供氧、载热和催化特性将传统煤气化反应解耦成两步反应，实现了燃料化学能梯级利用，避免了制氧过程昂贵投资和能耗代价，而且能定向调控煤气组分抑制CO2的生成，从源头实现了煤炭低成本、低能耗和低排放转化。本项目立足煤化学链气化技术与发电系统-CO2减排控制的有机耦合，研究煤气化产物品质主动调控的载氧体颗粒裁剪设计理论和方法，复杂气氛下载氧体解耦煤化学链气化过程中碳素演化规律与组分调控机制，阐明系统中化学能与物理能梯级匹配利用与碳素迁移、富集与分离耦合原理，构建煤化学链气化发电系统集成理论与方法和多维度评价体系框架，分析元素-能效-经济-碳排放之间竞争博弈平衡，最终实现煤化学链气化发电全过程源头节煤、节水、终端产品提值、CO2减排的多元平衡和优化。

通过多尺度分子裁剪设计，构建了适用于煤化学链气化反应特性的高活性铁矿石基载氧体，探究载氧体中不同活性组分及外源异质离子（Ni, Ce，Co，Ca，Mn）的协同促进作用，发展了载氧体优化制备方法和改性提质工艺，研究了不同水/载氧体条件下载氧体解耦煤化学链气化反应特征行为，阐明复杂气氛下载氧体解耦煤化学链气化过程中活性元素演化规律与组分调控机制，获得了不同温度场、流体场条件下煤化学链气化反应特性与组分定向调控方法，实现了载氧体解耦煤化学链气化高效转化。建立了包含煤化学链燃烧、煤化链气化、气体净化、CO2捕集、发电单元等在内的煤化学链燃烧/气化发电系统，构建了基于“经济-环境-能效”的多维度综合性能评价方法；研究了系统关键参数、工艺条件等对系统的性能影响，探究了系统的能量集成利用方法与路径，实现了煤化学链燃烧/气化发电系统的集成优化。建立了化学链燃烧/气化发电系统全生命周期评价方法，对比分析了煤化学链燃烧/气化发电系统与IGCC和传统火电厂的综合性能。项目相关研究成果共发表论文20篇，SCI论文20，申请/授权专利7件。培养硕士研究生7名。