EFFECT OF BIOFILM ON THE PHYSICAL-PROPERTIES OF SANDS CONTAMINATED WITH PHENOL

An experimental investigation was conducted to determine the relations hip between biofilm thickness and the resulting decrease in porosity a nd 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 wit h respect to influent phenol concentrations. The modified Kozeni-Carma n equation was used to estimate the thickness of biological Film, know ing the biofilm-affected permeability. Tile estimated values of the fi lm thickness varied from 0.04 min to 0.10 mm. Media porosity decreased between 29% and 51.3% in the sands with increased biofilm accumulatio n. A good correlation was observed between porosity and biofilm thickn ess in the range of low film thickness (0.066 mm - 0.099 mm).