An experimental study has been carried out to characterize bubble formation, growth, and detachment mechanisms in a stagnant liquid column. Both bubble frequency and bubble detachment size were measured in different gas flow rates, injector diameters and orientations, submergence height, and liquid properties. Experiments were performed for air injection flow rate ranges between 200 mlph and 12...

A characteristic length scale and a time scale are proposed to describe the dynamic growth and departure process of bubbles. A correlation between bubble departure diameter and bubble growth time is established thereby, and a predication formula for bubble departure diameter is suggested by considering the analogue between nucleate boiling and forced convection. # 1999 Published by Elsevier Sci...

Digital Image Analysis (DIA) has been employed to characterize the time evolution of a bubble injected from a single orifice into a pseudo 2-dimansional gas-solid fluidized bed. The injected bubble diameter increased with the square root of time before detachment. During bubble free flight in the bed, its diameter remains approximately constant. The center of mass of the bubble increases with t...

bubble columns are gas- liquid contactors that are widely used in chemical and bio- chemical industries. high mixing that result in high heat and mass transfer rates are amongst their advantages. heat transfer in a bubble column having a bundle of heaters investigated and the variation of heat transfer coefficient with variation in heaters pitch to diameter ratios in a bundle of heaters reporte...

Bubble columns are gas- liquid contactors that are widely used in chemical and bio- chemical industries. High mixing that result in high heat and mass transfer rates are amongst their advantages. Heat transfer in a bubble column having a bundle of heaters investigated and the variation of heat transfer coefficient with variation in heaters pitch to diameter ratios in a bundle of heaters reporte...

The success of flotation operation depends upon the thriving interactions of chemical and physical variables. In this work, the effects of particle size, bubble size, and collector dosage on the bubble loading in a continuous flotation column were investigated. In other words, this work was mainly concerned with the evaluation of the true flotation response to the changes in the operating varia...

This paper develops a procedure for estimation of the rise velocity of a swarm of large gas bubbles in a bubble column operating in the churn-turbulent flow regime. The large bubble swarm velocity is estimated by introducing two correction factors into the classical Davies—Taylor (1950) relation for rise of a single spherical cap bubble in a liquid » b "0.71Jgd b (SF) (AF) . The scale correctio...

frothers havea profoundeffectonbubble size and also flotation efficiency. in present study the effect of type and dosage of frothers on the flotation response of coarse particles of quartz was investigated.  therefore, flotation response of coarse particles using frothers such as mibc, pine oil, poly propylene glycol with concentration of 0, 25, 50 and 75 g/t, was obtained respectively. for all...

Frothers havea profoundeffectonbubble size and also flotation efficiency. In present study the effect of type and dosage of frothers on the flotation response of coarse particles of quartz was investigated.  Therefore, flotation response of coarse particles using frothers such as MIBC, pine oil, poly propylene glycol with concentration of 0, 25, 50 and 75...

Overall liquid side volumetric mass transfer coefficient kLa was determined experimentally for cocurrent Taylor flow moving upwards in a glass tube of an internal diameter of 3mm. Experiments were performed for physical absorption of oxygen in 20% aqueous solution of ethanol. Shadowgraph technique was deployed for precise measurements of bubble lengths and velocities. Experimental values of vol...