Determination of the ozone volumetric mass transfer coefficient in bubble column with two-fluid nozzle gas distributor

Abstract

Experimental investigation of gas-liquid mass transfer of ozone in water, in bubble column with two-fluid nozzle gas distributor (BKDM), under different operating conditions, is presented in this work. The main objective was to determine the ozone volumetric mass transfer coefficient, kL a, in calm uniform section of the column, under different values of gas and liquid flow rates. Obtained values of these coefficients were compared with the values in countercurrent bubble column. The critical liquid flowrate, when gas hold up reaches its maximum, was experimentally determined. It was shown that the maximum value of the ozone volumetric mass transfer coefficient is obtained just when liquid flowrate is at its critical value.

U ovom radu prikazani su rezultati eksperimentalnih ispitivanja prenosa mase gas-tečnost pri ozonizaciji vode u barbotažnoj koloni sa dvofluidnom mlaznicom (BKDM) pod različitim operativnim uslovima. Cilj ovih ispitivanja bio je određivanje vrednosti zapreminskog koeficijenta prenosa mase ozona u vodi, kLa, u mirnoj zoni kolone, pri različitim protocima gasne i tečne faze. U radu je dato i poređenje kLa u BKDM sa vrednostima kLa u klasičnoj protivstrujnoj barbotažnoj koloni sa poroznom pločom tj. fritom. Eksperimentalno je određena vrednost kritičnog protoka tečnosti, pri kojem sadržaj gasa u disperziji, u mirnoj zoni kolone, dostiže svoju maksimalnu vrednost. Rezultati su pokazali da se pri kritičnom protoku tečnosti dobija maksimalna vrednost zapreminskog koeficijenta prenosa mase ozona u vodi.