GAS-PHASE AXIAL-DISPERSION IN A SPRAY TOWER

Gas-phase axial dispersion (mixing of the composition of the gas phase along the longitudinal axis) was characterized in an enclosed spray t ower for purposes of establishing reactor type for the solute-solvent pair oxygen and water Test condition variables were spray tower height (TH), 1.52, 2.03 and 2.54 m; hydraulic loading(HL), 44.2, 66.3 and 88 .4 kg/m(2)s; the ratio of volumetric oxygen injection to water flow I- ate (G/L), 1.0, 2.5 and 5.0%; the ratio of volumetric bulk tower gas r ecirculation flow rate to water flow rare (BG/L), 0, 500 and 700%; and bulk tower gas recirculation direction, counter-current to and cocurr ent to the water flow. Gas composition measurements (% O-2) made acros s the long axis of the tower under steady-state conditions provided 10 20 independent observations and 240 gas composition profiles. Factors showing a significant effect (P<0.05) on gas composition were TH, HL, G/L and BG/L. Sample location as a percentage of TH did not have a sig nificant effect on gas composition and accordingly profile slopes were not different from zero (P>0.05). Profile data indicate a completely mixed gas phase within the tower The dispersion observed was attribute d to the lack of a significant pressure drop along the axis of the rea ction vessel, forces due to nozzle operation, and to bulk tower gas re circulation.