Abstract: The two-stage gasifier with heat recovery via chemical energy can improve heat recovery of high-temperature syngas effectively. In order to understand the flow pattern in the new two-stage gasifier, a cold model experimental device was set up. The pressure drop of second stage and velocity distribution in the gasifier were examined. The results showed that Montiller empirical equation could accurately predict the pressure drop of the second stage. When gas reached the bed surface of the second stage, an impact region was formed. The axial velocity attenuation equation of single nozzle on the top and downward radial velocity attenuation equation of four nozzles impacting were fitted out. Regarding the radial distribution of axial velocity, the center axial velocity appeared to be the largest and decayed the fastest. The distance of axial position from pipe flow region of four nozzles impacting was shorter than single nozzle on the top by 1.8D.

Key words: two-stage gasifier, pressure drop, velocity distribution

摘要： 化学热回收两段组合式气化炉有效地提高了高温合成气的显热回收。为进一步了解该新型两段炉内气体的流动规律，在自行搭建的冷模实验装置上，考察了该组合式两段炉内的二段床层压降以及速度分布情况。研究表明,采用Montiller经验公式能够准确预测二段固定床的床层压降，当气体达到二段床层表面时，将产生一个冲击区。拟合得到单喷嘴顶喷的轴向速度衰减公式以及四喷嘴撞击后的向下径向射流速度衰减公式。轴向速度的径向分布中，中心气速最大并且衰减最快，采用四喷嘴对喷的形式达到管流区所需的轴向距离较单喷嘴顶喷小1.8D。

关键词: 两段炉, 压降, 速度分布