A Study On Liquid Flowing Inside The Higee Rotor

Higee, which exerts centrifugal force as high-gravitec force to intensify mass transfer and chemical reaction between gas and liquid phases, is a new type of machine in chemical industry. The purpose of this dissertation is to study how liquid flows inside the higee rotor. For the purpose, two experiments are employed. Based on results of experiments, a mathematical model is built. The dissertation also includes a study of mass transfer coeffecients and applications of conclusions.The first experiment is to study liquid flowing inside the rotor by visual investigation, and try to measure the thickness of liquid film on the surface of the packing. With a video camera, which is fixed on the rotor and naturally, goes with the rotor synchronously, one can see liquid flowing inside the rotor packing .The video image gives direct evidence of flow patterns. By this method, we know that when the centrifugal acceleration is less than 200 times of gravity, in most of packing, most of liquid flows in films except in the zone closed to the inner edge for a few millimeters. Furthermore, its peripheral speed is almost as same as the rotor's. Having seen phenomena, we use image analytic method to measure film thickness on packing surface. On the foam metal packing, it is about 30-80 microns. These numbers are clearly higher than that on wire mesh packing, it is about 10 microns. The difference may be related to the structure and the roughness of packing surface.Close to the inner edge of the packing, the liquid flowing is rather complex. The liquid which comes from nozzles dashes against rotating packing violently, then breaking, reforming, making huge amounts of fresh surfaces. In this section, two flowing directions are observed. One is the radial flow that comes from the nozzle; the other is peripheral flow that comes from resisted radial flow having changed its flowing direction. The two flow directions make extremely high mixing in just a few millimeters.The second experiment is to measure the liquid residence time distribution in the packing. There are two conductivity sensors fixed on the rotor. When the tracer is injected into the packing, the two sensors give out relationships between conductivity and time. Aided by a computer, the residence time distributions are gotten under a series operating conditions. The results show that the rough range of mean residence time is about several hundred milliseconds, and it does not change with the countercurrent gas flow rate. The results also...