【作者】 徐玉杰；

【导师】 金红光； 蔡睿贤；

【作者基本信息】 中国科学院研究生院（工程热物理研究所） ， 工程热物理， 2008， 博士

【摘要】 能源、环境与经济的相容协调发展是21世纪能源科学研究的重要发展方向,以CO₂为主的温室气体引起的全球气候变暖是能源环境问题中的焦点和难点。煤基能源动力系统中控制CO₂已成为能源领域的重要研究课题,清洁能源载体氢气的制取也是能源系统发展的前沿课题。本文依托国家自然科学基金和国家高科技研究计划等重要科研项目,在关键过程机理、系统集成和技术路线的多层面上,开展了煤气化系统与双燃料重整系统的集成理论研究,提出了控制CO₂的部分煤气化系统和双燃料互补的氢电联产系统,预测了新系统的经济环境效益,并探索了适合中国的能源技术路线。为开拓高效环保的洁净煤发电系统,开展了煤气化系统中燃料转化过程整合机理以及CO₂分离一体化机理的研究。建立了煤气化、合成气燃烧和半焦燃烧过程整合的化学能与物理能梯级利用关系式;揭示组分和品位对燃料转化过程中能量匹配的影响;发现存在最佳的气化炉碳转化率,使燃料转化过程不可逆损失最小;分析燃料转化过程与CO₂分离过程的整合关系,揭示纯氧燃烧分离CO₂的部分煤气化系统实现了燃料转化过程与CO₂分离过程一体化。针对IGCC系统投资成本高的科技难题,本研究从“组分对口、分级转化”思路出发,基于燃料化学能与物理能综合梯级利用原理以及CO₂分离一体化的整合机理,提出控制CO₂的部分煤气化联合循环系统;揭示系统性能曲线簇具有包络线的特性规律,发现系统热效率在变量可行域内具有最佳值的特性。从热力性能、经济性能和环保性能等多方面与IGCC系统进行比较分析,指明新系统具有高发电效率、低投资成本和低能耗分离CO₂的优势。面临我国“煤多气少”的能源特点,以及针对传统天然气重整过程消耗大量优质燃料的问题,本研究提出了煤与天然气互补制氢联产系统。基于能的品位概念,建立煤与天然气互补的能量转化过程品位关系式;揭示双燃料化学能释放过程中能的梯级利用特性;采用图像（火用）分析方法,并通过与传统制氢系统比较,阐明煤与天然气互补制氢联产系统热力性能提高的根本原因。结合中国能源可持续发展战略,采用MESSAGE模型,对本文提出的部分煤气化系统和双燃料互补系统在中国电力和交通两大耗能领域的发展进行情景分析。通过对电力行业中控制CO₂的不同技术路线的发展情景比较,指出发展诸如本文提出的洁净煤发电系统能满足能源、经济、环境的协调发展,是适合中国的先进洁净煤发电技术路线。另外,交通燃料的剧增是导致中国石油对外依存度越来越大的一个主要原因。本研究以双燃料互补系统制甲醇代替交通燃料作为典型案例,预测新型交通燃料替代技术在中国未来交通领域发展情景,指出发展经济可行的煤代油技术路线是非常必要和迫切的。更多还原

【Abstract】 Harmonious development of energy resource, environment and economy is the important forward direction of energy research in 21^st century. Global warming climate brought by main greenhouse gas CO₂ has been the focus and difficulty of energy science. CO₂ control of coal-based energy power system has been the topic of energy field, and the production of hydrogen that is clean energy carrier has been also paid attention. Supported by the National Natural Science Foundation of China and the Hi-tech Research and Development Program of China, from the aspects of key process mechanism, system integration and technology pathway, integration theories of coal gasification system and dual fuel reforming system are studied, and partial coal gasification system with CO2 capture and dual-fuel system with hydrogen and electricity production are proposed, and also, economic and envirmental benefits brought by the new systems are predicted, technology pathway suitable for China is suggested.To exploit high-efficiency and friendly-environment clean coal power system, integration mechanism of fuel conversion processes and integrative mechanism of CO₂ control in coal gasification system are developed. The equation of cascaded utilization of chemical energy and physical energy for integration of processes that include coal gasification, syngas combustion and char combustion is built. The equation reveals that the relation of composition and energy level to energy matching during the integration of the fuel conversion processes. This investigation shows there is an optimized GCCR （gasification carbon conversion ratio） to make irreversibility of fuel conversion processes minimal. Furthermore, integration relation between fuel conversion process and CO₂ separation process is analysized. It was revealed that partial coal gasification system adopting oxy-fuel combustion realizes integration of fuel conversion and CO₂ control.Aiming at high invest cost of IGCC system, based on cacaded conversion of fuel, the principle of cascaded utilization of chemical energy and physical energy, and integration mechanism of CO₂ control, partial coal gasification combined cycle with CO₂ capture is proposed. The performance characteristics of the system are revealed. Within the feasible range of variables, thermal efficiency of the system has maximal value. From the aspects of thermodynamic, economic and environmental performances, the new system is compared with IGCC system. The comparison shows the new system realizes higher thermal efficiency, lower investment cost and lower CO₂ separation energy consumption.In the face of China’s energy resource structure with more coal and less natural gas, and aiming at a large of high quality fuel is consumed in the conventional reforming process of natural gas, dual fuel （natural gas and coal） energy system with hydrogen and electricity production is proposed. Based on the conception of energy level, the level equation of fuel conversion process, which describes the complementary utilization of coal and natural, is deduced. By the use of the equation, the characteristic of cascaded utilization of energy during chemical energy release of dual fuel is revealed. By the use of EUD, and compared with conventional systems with hydrogen production, the reasons of higher thermodynamic performance of the new system is explained.Based on sustainable energy development strategy of China, by the use of the MESSAGE model, scenarios of energy supply system of electricity and transportation are investigated, which include partial coal gasification system and dual fuel system with methanol production proposed by this thesis. Through comparison of different CO₂ control tenology pathways in electricity industry, it was pointed out that the clean coal technology such as the partial coal gasication system can meet harmonious development of energy, ecnomy and envirment. It is expected to be promised pathway suitable for China for CO₂ mitigation. Furthermore, speedy increasing fuel for transportation is an important reason that oil import increase speedily. This study use dual fuel system with methanol production as typical case, and predict scenario development of the new-type fuel for transportation substituting for oil, and point out that techonology patyway of economic feasible coal substituting for oil is necessary.更多还原