چكيده به لاتين
Abstract:
Bubble column reactors are widely used in various chemical, petrochemical and waste water treatment industries. These reactors have many advantages such as high heat and mass transfer rate and low operating and maintenance costs. According to research conducted on the bubble column reactors, more research was done on the investigation of operational parameters such as; the bubble properties, flow regimes, heat and mass transfer coefficient and gas holdup in particular.
In this research, experimental studies in the field of gas holdup for bubble columns of gas - liquid for three liquid (water, gasoline and Behran motor oil) with considering of investigation the effect of stirrer agitation on gas holdup was done.
First, aims and steps of the study was discussed, second, effective parameters on gas holdup in bubble column reactor such as, liquid properties, operating conditions, superficial gas velocity, dimensional of the column and the kind of sparger was studied. Then the setup was designed was built.
For the system and operating conditions analyzed in the present work, by increasing viscosity and surface tension, gas holdup decreased, because of increasing coalescence and size of bubbles, which produced from sparger, in high viscosity and surface tension. So, the most gas holdup was obtained for gasoline. Because of liquid vortex and air channelling by stirrer, in material with low viscosity, gas holdup was decreased than low speed of stirrer, but in high viscosity materials because of decreasing liquid vortex and break down of bubbles by stirrer, gas holdup was increased in all speeds. In conclusion, the best stirrer speed for increasing of gas holdup in water and gasoline was 150 rpm and for Behran motor oil was 400 rpm.
Keywords: Bubble column, gas holdup, viscosity, surface tension, stirrer
