Improvements in Biofilm Processes for Wastewater Treatment

Husham T. Ibrahim, He Qiang, Wisam S. Al-Rekabi and Yang Qiqi

This review paper intends to provide an overall vision of biofilm technology as an alternative method for treating waste waters. This technology has been gaining popularity through the years, mainly because many wastewater treatment plants, which are still used Activated Sludge Process (AS) are present some shortcomings when exposed to increased hydraulic and organic loads. Fundamental research into biofilms is presented in three sections, Biofilm Types and Characterization, Advantages and Drawbacks and Design Parameters. The reactor types covered in this review are: un-submerged fixed film systems (trickling filters and rotating biological contactors) and submerged fixed film systems (biological aerated flooded filters, submerged aerated filters, biofilm up-flow sludge blanket, fluidized bed, expanded granular sludge blanket, biofilm airlift suspension, internal circulation, moving bed biofilm and membrane biofilm) reactors.