Journal
ENVIRONMENTAL TECHNOLOGY
Volume 38, Issue 11, Pages 1362-1375Publisher
TAYLOR & FRANCIS LTD
DOI: 10.1080/09593330.2016.1228699
Keywords
Woodchip bioreactor; temperature; denitrification; hydraulic residence time; dual-porosity
Categories
Funding
- VINNOVA, The Swedish Innovation Agency [P31054-1]
- Luossavaara-Kiirunavaara Aktiebolag (LKAB)
- Boliden AB
Ask authors/readers for more resources
Nitrate removal rates in a mixture of pine woodchips and sewage sludge were determined in laboratory column studies at 5 degrees C, 12 degrees C, and 22 degrees C, and at two different hydraulic residence times (HRTs; 58.2-64.0 hours and 18.7-20.6 hours). Baffles installed in the flow path were tested as a measure to reduce preferential flow behavior, and to increase the nitrate removal in the columns. The nitrate removal in the columns was simulated at 5 degrees C and 12 degrees C using a combined Arrhenius-Monod equation controlling the removal rate, and a first-order exchange model for incorporation of stagnant zones. Denitrification in the mixture of pine woodchips and sewage sludge reduced nitrate concentrations of 30mgNL(-1) at 5 degrees C to below detection limits at a HRT of 58.2-64.0 hours. At a HRT of 18.7-20.6 hours, nitrate removal was incomplete. The Arrhenius frequency factor and activation energy retrieved from the low HRT data supported a biochemically controlled reaction rate; the same parameters, however, could not be used to simulate the nitrate removal at high HRT. The results show an inversely proportional relationship between the advection velocity and the nitrate removal rate, suggesting that bioreactor performance could be enhanced by promoting low advection velocities.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available