Please use this identifier to cite or link to this item:
http://hdl.handle.net/2282/899
|
| Title: | Effects of initial molecular weight on removal rate of dextran in biofilms |
| Authors: | Bakke, Rune
Milferstedt, Kim
Kommedal, Roald
Morgenroth, Eberhard |
| Issue Date: | May-2006 |
| Publishers version: | doi:10.1016/j.watres.2006.02.032 |
| Abstract: | Degradation kinetics of different size dextrans in a biofilm reactor were evaluated.
Degradation rates of dextran standards, measured as time series of oxygen utilisation rates
(OUR), decreased with increasing initial molecular weight. Removal of bulk phase TOC with
time was highly correlated (R2 > 0.99) and could be modeled with a variable half order
degradation rate expressions. A power correlation between initial molecular weight and the
variable half order degradation rate coefficient was found for polymers in the range 6-500
kDa. Degradation of dextran in the colloid size range (MW > 1 MDa) did not follow the same
kinetics. Reductions in the observed removal rate with polymer size can be explained by the
effect of reduced diffusivities of the substrate, without assuming reaction rate effects. This
suggests that removal of polymers and particles in biofilm systems is transport limited. |
| Keywords: | Dextran
Biofilm
Diffusion
Hydrolysis
Half-order kinetics |
| Publisher: | Elsevier |
| Document type: | Journal article |
| URI: | http://hdl.handle.net/2282/899 |
| Appears in Collections: | Institutt for prosess-, energi- og miljøteknologi
|
This item is protected by a usage licens. All items in TEORA are protected by copyright.
|
