【作者】 高建强；

【导师】 宋之平； 王兵树；

【作者基本信息】 华北电力大学（河北） ， 热能工程， 2005， 博士

【摘要】 我国能源生产以煤为主的,为了克服燃煤带来的环境污染问题,实现能源生产的可持续发展,循环流化床(CFB)煤燃烧作为一项洁净煤发电技术,在我国电站锅炉中已开始得到推广应用。随着我国环保法律和法规的健全与实施,对火电站的排放要求在不断提高,监督力度不断加强,大型CFB 锅炉在我国电站中的应用也将越来越普遍。我国目前投入运营的大型CFB 机组还很少,其设计和运行经验均不足。借助计算机仿真技术,建立包含CFB 锅炉机组所有主辅系统在内的全工况实时仿真模型,用于分析预测CFB 锅炉整体性能、研究机组设计和运行中存在的问题,具有重要意义。基于先进的STAR-90 仿真系统,提出了通过系统分解和子系统集成的方法,解决复杂大系统的建模过程中遇到的困难,首次将工程模块化建模方法用于大型CFB锅炉机组仿真模型的建立,成功地研制完成了涵盖CFB 锅炉所有辅助系统在内的我国首台450t/h循环流化床锅炉机组实时仿真模型。重点研究并建立了CFB 锅炉机组特有设备和过程的动态数学模型,研究开发了其实时仿真新算法,并对各新算法进行了通用模块化设计,为系统整体模型的建立和模型精度的提高创造了有利条件。新算法主要包括燃烧室、旋风分离器、回料器、点火风室、风水混冷多仓室冷渣器、单相介质换热器等仿真算法。深入研究了模块化建模方法在单相、汽液双相和气固双相等各类流体网络系统建模中的应用,提出了一种通过系统分解和集成的方法,有效地解决了各类复杂流网系统建模困难的问题,即:将复杂流网系统分解为若干个典型子网络,再通过网络节点集成为整个流网系统模型。首次将工程模块化建模方法与流体网络模型的矩阵法求解有机结合,对流网模型进行了改进,开发了流网模型自动生成软件,实践表明,这既提高了流网模型的建模效率,又提高了模型的仿真精度。以机组的运行数据为基础,对我国首台450t/h CFB 锅炉机组的流化效果,以及床压、床温等主要运行参数的变化规律进行了分析总结。为大型CFB 锅炉机组仿真模型的校验和完善提供了数据依据。通过仿真试验,研究了大型CFB 机组的整体动态和静态特性,并用实际机组运行数据对模型的仿真结果进行了验证,结果表明所建模型可以正确模拟CFB 机组运行特性。本文所建立的450t/h CFB锅炉机组实时仿真模型,已在我国首台125MWe CFB单元火电机组和200MWe 母管制CFB 火电机组仿真机中得到了成功应用。更多还原

【Abstract】 Coal is the primary energy source in China, but coal combustion brings to serious environment pollution. To maintain the sustainable development of energy industry, circulating fluidized bed (CFB) combustion has already begun to be a popular technology of clean coal combustion in power plant boilers in China. With the development of supervision mechanism and implementation of stricter environment protection rules and laws, it can be imagined that the large-scale CFB boilers will be more widely used in coal fired power plants. At present, there are few large-scale CFB boiler units, which have already been put into use in China, so it is scare of experiences in design and operation. At the same time, people understanding of working process mechanisms in CFB is far from satisfied because of its complex nature. With the support of computer simulation technology, the real-time simulation models of full working scope which contain the main systems and auxiliary systems can be set up, it has an important significance to analyze the overall performances of CFB boiler and solve the problems existing in its design and operation. Based on the STAR-90 simulation system, the method of decomposing and integrating models of CFB boiler unit is studied, and the difficulties in modeling of the large and complex system can be well settled, by properly decomposing and integrating the systems. The engineering modular modeling method is firstly used in developing the real time dynamic simulation model of large scale CFB boiler unit, and the real-time engineering modular simulation model of the 450t/h CFB boiler unit which is the first of its kind made in China is successfully set up, including all its auxiliary systems. According to the mass and energy balance principles, the math models of the equipment and process in CFB boiler unit are founded, and its modular simulation algorithms are set up, mainly include combustor, cyclone separator, the firing gas duct, ash cooler, J-type loop seal valve, one-phase medium heat exchanger and so on. The modular modeling method is also introduced to fluid network model development of CFB boiler unit. The system model integration methods of all kinds of fluid networks, such as one-phase, steam-water and gas-solid two-phase fluid networks etc., are discussed. By combining matrix solving the math models of fluid network with modular modeling method, the model precision and the efficiency of modeling are greatly improved. On the basis of actual operation data of the 450 t/h CFB boiler unit, the dynamic characteristics of the process parameters of the unit such as gas-solid pressure, bed temperature etc., is systematically studied. It provides a basis for verifying and improving the fidelity of the simulation model. With the test results of the real-time simulation model of CFB boiler, the dynamic and static characteristics of the CFB power unit is studied, simulation results show that the models can correctly simulate the operation performance of CFB boiler unit, and it is good for understanding and mastering the skills in operation and regulation of the large-scale CFB power unit. With the support of STAR-90 simulation system, the author develops the first real-time simulation model of the 450t/h CFB boiler unit, which is successfully put into use in the first 125MW CFB power unit simulator and 200MW header style CFB power unit simulator in China. It concludes that the engineering modular modeling method is suitable for complex system modeling and model debugging, and it is convenient for accumulating and reusing the model knowledge as well.更多还原