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.
Keywords: airlift reactors, hydrodynamics, gas hold–up, mass transfer, biological reactors, photobioreactors, domestic wastewater, wastewater treatment, domestic effluent