US EPA

3104298 

Journal Article 

Use of a dynamic gassing-out method for reactivity and oxygen diffusion coefficient estimation in biofilms 

Khlebnikov, A; Samb, F; Perringer, P 

1998 

1 

Water Science and Technology
ISSN: 0273-1223
EISSN: 1996-9732 

BIOSIS/98/21916 

37 

4-5 

4-5 

English 

BIOSIS COPYRIGHT: BIOL ABS. p-toluenesulphonic acid degradation by Comamonas testosteroni T-2 in multi-species biofilms was studied in a fixed bed biofilm reactor. The polypropylene static mixer elements (Sulzer Chemtech Ltd., Switzerland) were used as a support matrix for biofilm formation. Biofilm respiration was estimated using the dynamic gassing-out oxygen uptake method. A strong relation between oxygen uptake and reactor degradation efficiency was observed, because p-toluenesulphonate degradation is a strictly aerobic process. This technique also allowed us to estimate the thickness of the active layer in the studied system. The mean active thickness was in order of 200 mum, which is close to maximum oxygen penetration depth in biofilms. A transient mathematical model was established to evaluate oxygen diffusivity in non-steady-state biofilms. Based on the DO concentration profiles, the oxygen diffusion coefficient and the maximum respiration activity were calculated. The oxygen diffusion co