(1. 中南大学 冶金与环境学院,长沙 410083;
2. 中南大学 难冶有色金属资源高效利用国家工程实验室,长沙 410083)
摘 要: 建立24罐8层火道顺流式罐式炉温度场、残余挥发分浓度场的二维数学模型,模型中包含多孔介质渗流传热模型、固相活塞流模型、异相热解反应动力学模型及等效热流密度边界模型4个部分,并通过该模型研究罐式炉中石油焦热解传质传热过程。结果表明:在给定工况下,石油焦挥发分热解反应主要在二至五层火道高度对应的料罐内进行;在六至八层火道高度对应的料罐内,形成长度约为2.0 m的高温煅烧带(T>1423 K),满足石油焦进一步聚合并实现碳结构重排的煅烧温度要求。经生产数据对比验证表明:该模型基本能够反映炉内温度的分布情况,可为罐式炉的温度自动化调控提供一定的理论依据。
关键字: 罐式炉;温度场;二维;高温煅烧带
(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. Central South University, National Engineering Laboratory of Efficient Utilization of
Refractory Nonferrous Metal Resources, Changsha 410083, China)
Abstract:The two-dimensional model for temperature field and residual volatile concentration field of petroleum coke calcination in vertical shaft calciner with 24 pots and 8 flues was developed. The model was mainly comprised of four parts, such as the model of seepage heat transfer in porous medium, solid phase plug flow model, heterogeneous pyrolysis reaction kinetics model and equivalent heat flux boundary model. In addition, the model was applied to research the heat and mass transfer process of petroleum coke pyrolysis. The results show that the volatile pyrolysis reaction mainly takes place in the pot at the heights of layers 2, 3, 4 and 5. A partial high-temperature zone with length of about 2.0 m (T>1423 K) is formed at the heights of layers 6, 7 and 8, which will further promote green coke polymerization and achieve carbon structure rearrangement. The model is validated based on measurement data, which can provide a theoretical basis for temperature automatic regulation of petroleum coke calcination in vertical shaft calciner.
Key words: vertical shaft calciner; temperature field; two-dimensional; high-temperature zone