Study on optimization of mass transfer enhanced by ceramic membrane ozone aeration

Abstract

Ozonation technology has problems such as low gas-liquid mass transfer efficiency and low ozone utilization. The improvement of ozone aeration conditions is an effective approach to enhance ozone mass transfer. In this regard, an experimental study of ozone aeration with ceramic membranes was carried out to characterize the microporosity and morphological structure of ceramic membranes, and to investigate effects of different operating conditions on ozone mass transfer. The results showed that the ozone mass transfer coefficient firstly increased and then decreased with the increase of inlet gas flow rate and gas-phase ozone concentration. The optimal conditions were 0.4 L/min and 28 mg/L. The hydrophobic modification of ceramic membrane surface could enhance the ozone mass transfer efficiency. Ozone solubility and mass transfer efficiency increased with the decrease of membrane pore size. With the increase of aeration pressure from 0.1 MPa to 0.5 MPa, the ozone mass transfer efficiency firstly increased and then decreased, and the optimal aeration pressure was about 0.3 MPa. The mechanism of ceramic membrane pressurized aeration to strengthen the ozone mass transfer was analyzed based on Young-Laplace equation.

Keywords

• ozonation process
• ceramic membrane
• aeration
• mass transfer efficiency