Effect of biofilm on the physical properties of sands contaminated with phenol

An experimental investigation was conducted to determine the relationship between biofilm thickness and the resulting decrease in porosity and permeability of local sands. Media tested consisted of two sizes of sands (0.2 and 0.3 mm). The study was carried out in three phases with respect to influent phenol concentrations. The modified Kozeni-Carman equation was used to estimate the thickness of biological film, knowing the biofilm-affected permeability. The estimated values of the film thickness varied from 0.04 mm to 0.10 mm. Media porosity decreased between 29% and 51.3% in the sands with increased biofilm accumulation. A good correlation was observed between porosity and biofilm thickness in the range of low film thickness (0.066 mm-0.099 mm).