Keywords: airlift reactors, hydrodynamics, gas hold–up, mass transfer, biological reactors, photobioreactors, domestic wastewater, wastewater treatment, domestic effluent
Hydrodynamic characterisation of an airlift reactor for domestic wastewater treatment
This study evaluates the hydrodynamic and mass–transfer behaviour of a 20–L airlift photobioreactor, employed for secondary wastewater treatment of domestic effluent. Gas hold–up (ε), as well as the volumetric mass transfer coefficient (kLa) was assessed as a function of superficial gas velocity (Ug) for both bi– and triphasic systems. In the experimental range of Ug investigated, the maximum kLa and ε obtained were in the order of 0.0074 s−1 and 0.035 for water/air system and 0.0097 s−1 and 0.026 for triphasic system respectively. The results indicate that this PBR is a good candidate for wastewater treatment, with lower power costs than other types of biological reactors.