Study On Two-phase Flow Characteristics Of Bubble Type Stirred Reactor

Structure of bubble type stirred reactor is designed by combining the characteristics of the bubbling tower and stirred tank.Gas distribution device is installed at the bottom of the reactor, and stirring device is installed near the liquid level. Gas bubbles into reactor through the gas distributor. Under the synergy of gas distributor and blender, it can not only increase the gas-liquid contact area, but also blend liquid with gas, thus the gas-liquid mixed more evenly.In this paper, the two-phase flow characteristics of Bubble type stirred reactor are qualitatively simulated based on ANSYS CFX. By analyzing different installation height of mixer blade and different gas velocity of flow field flow pattern, gas holdup contour, liquid velocity vector, shaft power, turbulent kinetic energy contour and turbulent kinetic energy dissipation contour, It can determines the best impeller installation height and the best gas velocity. The best impeller installation height is 280mm?h?320mm (1/3H?h?1/2H), and the best gas velocity is 0.03m/s.When the impeller speed is 400 r/min, it has the higher gas holdup and the ideal liquid velocity in the reactor. Gas-liquid mixing effect is more ideal.On the basis of numerical simulation, experimental study in the Bubble type stirred reactor was conducted emphatically from power and relative power consumption, gas holdup. And then through analyzing the data We can get the following conclusion:the numerical simulation results and experimental results are similar; the stirring power P gradually increased with the increase of stirring speed N In the form of index, which relation accord with P ? N3, and the power of mixing with gas is smaller than mixing without gas; when the stirring speed is a constant value,power consumption increased with increase of the density of mixing material; the relative consumed power reactor RPD< 1, relatively consumed power RPD gradually increased with increase of the speed of the impeller.