热风炉蓄热设计及优化

Design and optimization of regenerator for hot blast stove

随着工程设计要求不断提高、数值计算手段不断增强,当前已可以采用计算形式明确热风蓄热体换热过程的细节,对设计工作进行优化指导。对5座高炉热风炉蓄热体进行分析,讨论热风炉蓄热体设计优化条件、优化目标、优化变量间的关系,为蓄热体设计提供指导。在优化条件限制下,通过不同变量的目标比较,提出最优变量。以工程实际常用的耐火材料物理特性、工艺需求、煤气参数、操作为优化条件,以格子砖几何尺寸、蓄热体几何尺寸、不同耐材段蓄热体高度作为优化变量,通过数值计算的方法分析5座高炉热风炉蓄热体的传热过程,获得蓄热体传热过程参数。对比数值分析结果并分析其与投资、送风期热风温降等优化目标关系。5座高炉热风炉蓄热体数值分析结果表明,影响蓄热体高度方向温度分布的主导因素是蓄热体高度,不同耐材段蓄热体的高度受耐材使用温度限制;传热流量的主导因素是作业制度,热辐射传热与蓄热体表面黑度相关度较低,而结构格子砖几何尺寸不是蓄热体阻损的主导因素。结合分析结果给出5座高炉热风炉的优化建议,由优化条件、变量构成的准数可用于定量确定送风期热风温降,同时给出了蓄热体适宜的高径比以及热风炉数量、作业制度与格子砖几何尺寸的关系建议,可为今后的设计工作提供指导。

With the continuous improvement of engineering design requirements and the enhancement of numerical calculation methods,it is currently possible to use computational methods to clarify the details of heat transfer process for hot blast stove regenerator and provide optimization guidance for design work.The regenerators of 5 blast furnace hot blast stoves were analyzed,and the relationship between optimization conditions,optimization objectives and the optimization variables was discussed for the design guidance of regenerators.Under optimization conditions,the optimal variable was proposed by comparing different variables objectives.Taking physical properties,process requirements,gas parameters,and operations of commonly used refractory materials in engineering practice as optimization conditions,the geometric dimensions of checker bricks,geometric dimensions of regenerator and the height of regenerator in different refractory sections as optimization variables,the heat transfer process of regenerator for 5 blast furnace hot blast stoves was analyzed using numerical calculation methods,then obtained the heat transfer process parameters of regenerator.Compared the numerical analysis results and analyzed their relationship with optimization objectives such as investment and hot air temperature drop during the air supply period.The numerical analysis results of regenerator for 5 blast furnace hot blast stoves show that the dominant factor of temperature distribution in the height direction of regenerator is the height of regenerator,and the regenerator height in different refractory sections is limited by the usage temperature of refractory.The dominant factor in heat transfer flow is operating system.The correlation between thermal radiation heat transfer and surface blackness of regenerator is relatively low,while geometric size of structural checker bricks is not the dominant factor in the resistance loss of regenerator.Based on the analysis results,optimization suggestions for 5 blast furnace hot blast stoves are provided.The standard number composed of optimization conditions and variables can be used for quantitatively determining the temperature drop of hot air during the air supply period.The appropriate height to diameter ratio for regenerator and the relationship between the number of hot blast stove,operating system and geometric dimensions of checker bricks are also suggested.These conclusions can serve as guidance for future design work.