水煤浆气化炉气化过程的三区模型

THREE-REGION MODEL FOR GASIFICATION PROCESS IN COAL-SLURRY-GASIFIER

本文提出了水煤浆气化过程的三区模型,即燃烧区、二次反应区、回流化学反应区。在燃烧区中,首先进行反应的是回流流股中的可燃组分,其次是煤中的挥发分及碳等;二次反应区主要是燃烧产物的均相或非均相反应;回流区的化学反应则与喷咀结构,射流速度密切相关。各区的反应既不受热力学限制,也不为动力学控制,反应结果完全依赖于喷咀与炉体匹配形成的流场;其中回流是一个重要的工程因素,适当的回流量有利于二次反应的进行。

In this paper the three-region model for gasification in coalslurry-gasifier has been presented. They are regions of combustion9 secondary chemical reaction and recireulation chemical reaetiono In the combustion region, combustible constituents of reeireulating stream combust firstly, Combustion of volatile matter is only secondly. In the secondary chemical reaction region the key reactions are either, homogeneous or heterogeneous reactions of combustion products. Reactions in recirculation reaction region are closely related to the configuration of the burner and the jetting velocity. None of the reactions in the three regions is limited by thermodynamics or by kinetics. Results of reactions depend totally on the flow-field formed by the combinations of burner and gasifier. Recirculation is an important engineering factor. Appropriate recirculation is favourable to the,of secondary reactions.