甲醇制丙烯反应器喷嘴雾化性能的研究

雾化喷嘴系甲醇制丙烯（MTP）反应器内的关键反应物料分配构件，其雾化性能的优劣直接影响着对应催化床层覆盖区域内的传质和传热，从而影响到床层出口反应产物的分布。以反应器六级床层对应的雾化喷嘴为研究对象，分别以氮气（N₂）和水（H₂O）作为气相和液相模拟介质，通过“冷模”实验，考察了喷嘴气（液）流量与入口压力之间的关系，研究了喷嘴在不同气液比（G/L）下雾化粒径、雾化角度及雾化覆盖直径的变化规律。实验结果表明，喷嘴液相质量流量随着入口压力增大而逐渐增加，气相质量流量随着入口压力增加而迅速增加；当保持液相进料量为43.54 kg/h时，喷嘴由一次雾化变为二次雾化后，雾化角度由96.1°降至15.6°；当气液质量比G/L达到12.19时，雾化覆盖直径达到720mm，且雾滴的索泰尔平均粒径为16.3μm。

Investigations on the spraying properties of spraying nozzles distributed in Methanol-to-Propylene (MTP) reactor

Spraying nozzles designedly arranged in Methanol-to-Propylene (MTP) reactor are crucial distributors for the feedings of reactants.The atomizing properties of the nozzles take a direct effect on heat and mass transfer occurred in the nozzle-controlled areas correspondingly to catalytic bed, and thereby, the components of reaction products coming from the outlet of the catalytic bed is definitely affected by the heat-mass transfer.The nozzle of sixth catalytic-bed chosen as an experimental example was investigated by a cold model experiment.Nitrogen and water were taken as gas and liquid reactants respectively for testing the spraying properties.The relationships between gas (liquid) mass-flow and inlet pressure were investigated.Simultaneously, sauter mean diameter (SMD), atomizing angles and droplet-covered diameters (DCD) were also analyzed under different gas-liquid ratios (G/L).The experimental results show that the liquid mass-flow increases gradually with the inlet pressure, but the gas mass-flow increases rapidly with the inlet pressure; while the liquid feeding of the nozzle maintaining at 43.54kg/h, the atomizing angle decreases from 96.1° to 15.6° after changing from primary atomization to secondary one.When the gas-liquid ratio G/L varies to 12.19, SMD reaches to 16.3μm, and meanwhile, DCD of the nozzle is 720mm.