膜科学技術ジャーナル

概要

Hydrodynamic Study and Influence of Physicochemical Parameters on Gas Retention in a Submerged Membrane Bioreactor

Nsoe MN, Kofa GP, Marc H, Ndi KS, Kayem GJ

Gas-liquid reactors present transfer difficulties due to diffusion effects. It is necessary to master the aeration and hydrodynamics of the medium to conduct a better reaction and performance. For this purpose, a study in a submerged membrane bioreactor was been conducted. Gas retention was measured by the manometric method. The experiments were carried out at different temperatures; 25°C and 45°C, with a variable airflow rate of 3 to 16 mL/S and different solutions (osmosis water, ammonium formate solution, ammonium formate+salt solution, synthetic rubber effluent). The results show that gas retention increases with aeration rate and temperature. On the other hand, the more the medium becomes rich in organic substances, the more the gaseous retention decreases. The homogeneous fine-bubble regime is obtained for an airflow rate ranging from 3 and 10 mL/S of aeration. Beyond this flow rate, the regime becomes heterogeneous without a transition phase for ammonium formate and ammonium formate+salt solutions. The more the medium becomes rich in organic substances, the gas retention increases and K_La decreases. There is, therefore, a correlation between temperature, K_La and gas retention.