气升式环流反应器在气液或气液固三相反应以及分离过程应用广泛,为提高气液分布和传质性能,在气升式多段环流反应器的第2段引入射流,开发一种气升-射流式多段环流反应器.在160 L的实验装置中,以水-空气体系,研究了气升-射流式多段环流反应器的流体力学和传质特性.射流可减小上升气泡的弦长,提高总体气含率,改善下降段气液分布,增加环流液速,并最终使气液体积传质系数显著提高.射流液体量、射流角度、空气量及其分配对射流效果影响不同,选择射流角不大于45°,射流通气量占总通气量的比例不大于40%,且在能耗经济范围内提高射流量和通气量,可获得更理想的流体力学特性和高传质速率.%Air-lift loop reactor (ALR) is widely used for the gas-liquid/gas-liquid-solid multi-phase reaction or separation. In order to improve the gas distribution and to enhance the mass transfer in ALR and based on the conventional multi-stage air-lift loop reactor (MALR), the jet associated multi-stage air-lift loop reactor (MJALR) was developed by introducing a jet into the second stage of the MALR in present study. The hydrodynamics and mass transfer characteristics of the proposed MJALR were studied by using a MJALR of 160 L with water/air as working system. The experimental results show that introduction of the jet associated air-lift loop leads to the decrease of the raising bubble size, the increase of the total gas hold-up, the promotion of gas-liquid distribution in downcomer and the acceleration of loop flow. It was found that all these effects depend on the jet volume, jet incidence angle, inlet gas volume and gas allocation. Under the conditions as follows, the jet incidence angle is not larger than 45 ° and the gas allocation to the jet is not more than 40％ of the total gas volume, the hydrodynamics and mass transfer characteristics of the MALR can be highly improved by introducing the jet into it and by increasing the total gas volume within the range of the economic energy consumption.
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