DESIGN CORRELATIONS OF AN AIRLIFT TUBE REACTOR

Air-lift reactors are important gas-liquid contactors for gas separati on, purification, fermentation and waste water treatment on account of their simple construction and low energy consumption together with hi gh mass and heat transfer rates. Apart from the improved liquid mixing , air-lift reactors have no moving elements and the power requirement comes only from the air supply. A new air-lift tube (ALT)-type reactor was investigated in laboratory and pilot scale. A study was conducted to measure the effects of liquid properties (such as viscosity and de nsity) on the hydrodynamics of the ALT reactor. The systems used for t his study were: air/water, air/sodium hydroxide solution, air/sodium c itrate buffer solution and air/glycerine. Pressure drop in the reactio n tube, minimum and maximum gas velocities, pressure frequency and rec ycle liquid velocity in the recycle tube were measured under different experimental conditions using different tube diameters for the recycl e and reaction tubes. Design correlations for the above-mentioned para meters were developed by computer program in order to design an ALT re actor for gas-liquid reactions. The correlations are valid in the rang e 0.1-1400 m3 h-1 of the gas stream.