针对催化裂化汽油辅助反应器改质降烯烃工艺,在组合式气固环流反应器大型冷模实验装置上,研究分布器型式对环流反应器流体力学特性的影响.结果表明,在分布器上方0.50 m高度范围内分布器型式的影响较为明显,经过分布器的气体和颗粒对环流反应器内颗粒(团)的作用范围为:采用凹形球面板时主要作用于凹面上方中心区域,采用平面直孔板时主要作用于分布器上方投影区域,采用凸形球面板时主要作用于凸面上方及周围临近区域,受此影响的区域固含率较低,颗粒速度较高;采用三种分布器时,颗粒环流速度从大到小的顺序为平面直孔板>凹形球面板>凸形球面板,固含率的径向分布均匀性从好到差的顺序为凸形球面板>平面直孔板>凹形球面板.综合考虑流场均匀性及环流速度调节范围,认为平面直孔板分布器型式更适用于组合式气固环流反应器.%A large scale cold model experimental sotup of a compound gas-solid airlift loop reactor was established according to olefin reduction technology with auxiliary rcactor for FCC naphtha upgrading The effect of distributor typcs on hydrodynamics behavior in the airlift loop reactor was cxperimentally measured, and three types of distributor were involved including concave spherical perforated plate (concave SPP), plane perforated plate(PPP) and convex spherical perforated plate(convex SPP). The experimental results show that the effect of distributor types on the hydrodynamics behavior within 0. 50 m height upon the distributor is significant. The action scopes of gas and particle through the distributor on the particles(or clusters)in the reactor mainly locate in the central region above the concave surface for concave SPP distributor,in the projection region above the distributor for distributor,and in the upper region of convex surface and around neighboring region for convex SPP distributor. Furthermore,in these action scopes,the solid holdup is lower and the particle velocity is higher than that in the other scopes of the reactor. While adopting such three types of distributors, the descending order of particle circulating velocity is as follows:PPP＞concave SPP＞convex SPP; the descending order of radial uniformity of solid holdup is as follows: convex SPP＞PPP＞concave SPP. Therefore, combined the flow field uniformity with the adjustable range of circulating velocity, the adoption of plane perforated plate distributor is more feasible than the other two distributors in the compound gas-solid airlift loop reactor.
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