【作者】 赵斌；

【导师】 徐鸿； 杜小泽；

【作者基本信息】 华北电力大学 ， 热能工程， 2012， 博士

【摘要】 我国将节能减排定为钢铁工业重点研究目标之一,而高效回收和充分利用钢铁工业余热是未来钢铁生产深层次节能的突破口。随着国家大型钢铁项目的立项和节能减排的迫切要求,烧结工序中烧结机尾风箱烟气和烧结矿显热的高效回收与发电是亟待攻克的难题。论文以钢铁工业中烧结工序为研究对象,根据场协同原理和能量梯级利用方法,进行了烧结余热高效回收理论研究、烧结矿显热梯级回收实验研究、烧结余热高效回收装置及工艺研发和烧结余热电站优化选型与优化调度。四部分内容既相互独立又相互支撑、相互印证。主要科学问题涉及：1.建立烧结矿输送和冷却两个过程的换热模型,基于烧结能流图,揭示输送通道和冷却机内热质输运效应；根据对流传热优化的场协同原理,进行烧结矿气固换热机理分析,研发了立式冷却机和双螺旋冷却机,揭示中低温余热能传递中品位提升的科学本质。2.利用正交实验法进行烧结矿显热梯级回收实验,研究不同粒径、料厚、冷却凤量和进口风温下冷却机的换热特性,揭示烧结矿操作工艺和设备参数等因素对冷却机废气冷却速率和热源参数的影响,为冷却机的优化操作、设计和改进提供依据。3.根据协同回收和梯级利用方法,研发三进气余热锅炉和双工质热源余热锅炉,以期全面提升烧结余热回收装置的性能和效率,达到烧结余热热耗散最小的目标。进行烧结机及冷却机-余热锅炉-汽轮机热功转换的科学基础与循环协同规律研究,提出了烧结双余热源集成发电和旋冷机梯级发电先进工艺方案。4.以净发电功率为优化目标值,依据梯级利用方法,建立烧结余热电站热力计算和优化模型,进行热力系统及设备的优化选型。研究废气系统与汽水系统的耦合机制及冷却机适应烧结机制变化的响应策略,提出了单位烧结矿余热发电指标优化调度的方法,以达到对烧结余热电站运行的优化调度。论文从热能传递和转换的角度开展了烧结余热高效发电应用基础研究,开发了冷却机强化换热技术、烧结矿显热提取技术、烧结余热梯级回收技术和烧结余热电站优化选型四项关键技术。其研究成果为中低品位工业余热高效回收基础科学问题的研究提供了理论参考,也为钢铁工业节能减排提供了技术保障。更多还原

【Abstract】 Energy-efficient and emission-reducing has been taken as one of the important research targets in iron and steel industry in China, and efficient recovery and full use of the waste heat in iron and steel industry will be as the breakthrough of deep-level energy conservation in iron and steel production. With project selection of major iron and steel project and urgent demand in energy-efficient and emission-reducing in China, efficient recovery and power generation of sensible heat of flue gas from sintering machine tail bellows and sinter ore in sintering process is an urgent problem to overcome. In this dissertation, the sintering process in iron and steel industry is taken as the research object. And based on field synergy principle and energy cascade utilization method, lots of work including theoretical study on efficient recovery of sintering waste heat, experimental study on sensible heat cascade recovery of sinter, development of efficient recovery device and process about sintering waste heat and optimal selection and scheduling of sintering waste heat power station is done. Above four parts, they are independent of each other, support each other and prove each other. The major scientific issues involved are as follows:1. Heat transfer model of two processes including sinter conveying and sinter cooling is established. Based on the sintering energy flow diagram, thermomass transport effect on transport pathways and in cooler is revealed. According to field synergy principle of convective heat transfer optimization, the mechanism of sinter gas-solid heat transfer is analyzed, vertical sinter cooler and double-helix sinter cooler are developed, and the scientific essence of improvement of medium-low temperature waste heat grade is revealed.2. Combined with orthogonal experimental method, the experiment of sinter sensible heat cascade recovery is done. Heat transfer characteristic in different particle size, material thickness, cooling air volume and air temperature of the cooler inlet is discussed. The influence of sinter operation process and equipment parameters and other factors on cooling rate of cooler exhaust gas and heat source parameters is revealed. Above work can provide basis for the optimization operation, design and improvement of the cooler.3. According to the method of collaborative heat recovery and cascade utilization, the three-inlet HRSG and dual-source HRSG are developed to enhance comprehensively the performance and efficiency of the sintering waste heat recovery device, and to achieve the goal of minimizing the sintering waste heat dissipation. The dissertation researches scientific basis and circulation collaborative law of convertion from heat to mechanical energy among sintering machine and cooler, waste heat boiler and steam turbine, then puts forward advanced progress program about sintering double waste heat source integrated power generation and helical cooler cascade power generation.4. Net power output is taken as the optimization target. According to the method of cascade utilization, this dissertation builds thermodynamic calculation and optimization model of sintering waste heat power station, and makes optimized selection of thermal system and equipment, at the same time, researches coupling mechanism of exhaust system and steam-water system and response strategy of cooler adapting to sintering mechanism change, then provides the optimal dispatch method about unit sinter waste heat power generation indicators to achieve optimized scheduling to sintering waste heat power station operation.At the view of heat transfer and conversion, this dissertation carries out applied basic research on efficient power generation of sintering waste heat, and develops four key technologies includes the technology of cooler heat transfer enhancement, technology of sinter sensible heat extraction, technology of cascade recovery of sintering waste heat, technology of optimizated selection of sintering waste heat power station. The research results provide theoretical reference for basic science problem research about low-medium grade industrial waste heat efficient recovery, and also offer technical assurance for energy-efficient and emission-reducing in the iron and steel industry.更多还原