多点供热对焦化过程影响的数值分析与优化

 针对多点供热式焦炉的结构特征以及工艺特点，建立了描述其内部流动、传热以及燃烧等过程的燃烧室-炭化室三维非稳态数理模型，并进行了数值求解；考察了多点供热方式下的高向加热均匀性以及NO的生成量，与传统下喷式单点供热方式进行了对比分析；并进一步针对装炉煤的水分、堆密度和初始温度，空气和高炉煤气分级数目，以及废气循环倍率等操作参数开展了正交试验模拟分析。研究结果表明：采用分级燃烧技术，有效提高了焦饼的高向温度均匀性，使其在大规模生产的同时，保证了焦炭的质量；同时，较之传统单点供热焦炉，有效改善了局部燃烧温度过高的现象，使NO体积分数明显减少；废气循环倍率、装炉煤堆密度对焦炉生产的影响最为显著。这对焦炉的大型化、高效节能以及清洁生产有一定的指导作用。

Numerical analysis and optimization of multiple-point heat supply and its influence on coking processes

According to the structure and process characteristics of large-capacity coke oven with multiple-point heat supply，a 3-D mathematical model was established to describe the flow，combustion and heat transfer process in coupled coking and combustion chambers. The numerical solution was obtained. The impacts of multiple-point heat supply on the coking process were analyzed and compared with the conventional coke oven. The comparison showed that the multiple-point heat supply plays a significant role in the coking process. The mass percent of moisture，the bulk density，the initial temperature，the number of flue air points and the circulating ratio of flue gas were analyzed by the orthogonal experiment. It indicates that the staged combustion technology can effectively improve gas temperature uniformity along the vertical direction，and the production as well as the quality of the coke is improved. Meanwhile the volume percent of NO of exhaust is reduced. The results can be applied to large-scale coke oven design，process optimization，and clean production in coke oven industry.