Biological Fouling of Fine Bubble Diffusers: State‐of‐Art

Abstract

This paper reviews the current state‐of‐understanding of biological fouling of fine bubble diffusers. Results of a survey conducted in the United Kingdom and United States which implicates biological sliming as a major cause of fine bubble diffuser clogging are reviewed. Factors contributing to the bioclogging of diffusers are discussed in light of current studies. Newly developed methods for the analysis of diffuser fouling both in the laboratory and the field are described. Included are procedures for the laboratory measurement of specific permeability, diffuser bubble release pressure, dynamic wet pressure and air flow profiles over the diffuser. Illustrations of these test methods are cited for one plant experiencing severe biofouling.