Waste Ochre for Control of Phosphates and Sulfides in Digesters at Wastewater Treatment Plants with Enhanced Biological Phosphorus Removal
Öfverström, Svetlana ; Davidsson, Åsa LU
; Haghighatafshar, Salar
LU
; Kjerstadius, Hamse
LU
and la Cour Jansen, Jes
LU
(2020)
In Clean Technologies
2(1).
p.116-116
- Abstract
- Ochre, waste iron sludge from the treatment of iron rich groundwater for potable use, makes up a significant waste problem. Furthermore, wastewater treatment plants with enhanced biological phosphorus removal and the digestion of sludge are in lack of iron for the prevention of hydrogen sulfide production and the release of phosphorous during anaerobic digestion. Thus, the addition of ochre to anaerobic digestion is a potential beneficial reuse of ochre. Sludge from wastewater treatment plants with enhanced biological phosphorus removal was used for the experiments. Batch and continuous pilot-scale tests were performed for the mesophilic digestion of primary and waste-activated sludge with different doses of ochre. Two different doses of... (More)
- Ochre, waste iron sludge from the treatment of iron rich groundwater for potable use, makes up a significant waste problem. Furthermore, wastewater treatment plants with enhanced biological phosphorus removal and the digestion of sludge are in lack of iron for the prevention of hydrogen sulfide production and the release of phosphorous during anaerobic digestion. Thus, the addition of ochre to anaerobic digestion is a potential beneficial reuse of ochre. Sludge from wastewater treatment plants with enhanced biological phosphorus removal was used for the experiments. Batch and continuous pilot-scale tests were performed for the mesophilic digestion of primary and waste-activated sludge with different doses of ochre. Two different doses of ochre corresponding to molar ratios of 1 and 2 moles Fe 3+ /mole P released in the batch test resulted in 29% and 57% reductions of phosphates respectively in the sludge liquor compared to the control sludge without inhibiting the digestion process. In the pilot experiment, the dosing of ochre at both a high and low dose (molar ratios of 1.6 and 0.8 Fe 3+ /S 2− , respectively) resulted in an immediate drop in the H2S concentration (from >2000 ppm down to 570 ppm), while the control reactor still produced biogas with a high hydrogen sulfide concentration. The inhibition of the digestion process was observed (accumulation of acetate) at the higher dose. In a second pilot scale experiment, lower doses of ochre were tested continuously (1.5 and 0.75 mole Fe 3+ /mole Preleased) to avoid any inhibition, while evaluating the phosphate precipitation. A reduction of phosphates in sludge liquor (33% and 66% for the low and high doses respectively) was obtained. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/c0f3e844-f935-497c-8d8d-a611bf6ee3a7
- author
- Öfverström, Svetlana
; Davidsson, Åsa
LU
; Haghighatafshar, Salar
LU
; Kjerstadius, Hamse
LU
and la Cour Jansen, Jes
LU
- organization
- publishing date
- 2020-03-06
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- waste ochre, biogas, enhanced phosphorus removal, hydrogen sulfide, phosphates precipitation
- in
- Clean Technologies
- volume
- 2
- issue
- 1
- pages
- 126 pages
- publisher
- MDPI AG
- external identifiers
-
- scopus:85128083173
- ISSN
- 2571-8797
- DOI
- 10.3390/cleantechnol2010008
- language
- English
- LU publication?
- yes
- id
- c0f3e844-f935-497c-8d8d-a611bf6ee3a7
- date added to LUP
- 2020-03-06 16:19:47
- date last changed
- 2023-11-22 15:27:20
@article{c0f3e844-f935-497c-8d8d-a611bf6ee3a7,
abstract = {{Ochre, waste iron sludge from the treatment of iron rich groundwater for potable use, makes up a significant waste problem. Furthermore, wastewater treatment plants with enhanced biological phosphorus removal and the digestion of sludge are in lack of iron for the prevention of hydrogen sulfide production and the release of phosphorous during anaerobic digestion. Thus, the addition of ochre to anaerobic digestion is a potential beneficial reuse of ochre. Sludge from wastewater treatment plants with enhanced biological phosphorus removal was used for the experiments. Batch and continuous pilot-scale tests were performed for the mesophilic digestion of primary and waste-activated sludge with different doses of ochre. Two different doses of ochre corresponding to molar ratios of 1 and 2 moles Fe 3+ /mole P released in the batch test resulted in 29% and 57% reductions of phosphates respectively in the sludge liquor compared to the control sludge without inhibiting the digestion process. In the pilot experiment, the dosing of ochre at both a high and low dose (molar ratios of 1.6 and 0.8 Fe 3+ /S 2− , respectively) resulted in an immediate drop in the H2S concentration (from >2000 ppm down to 570 ppm), while the control reactor still produced biogas with a high hydrogen sulfide concentration. The inhibition of the digestion process was observed (accumulation of acetate) at the higher dose. In a second pilot scale experiment, lower doses of ochre were tested continuously (1.5 and 0.75 mole Fe 3+ /mole Preleased) to avoid any inhibition, while evaluating the phosphate precipitation. A reduction of phosphates in sludge liquor (33% and 66% for the low and high doses respectively) was obtained.}},
author = {{Öfverström, Svetlana and Davidsson, Åsa and Haghighatafshar, Salar and Kjerstadius, Hamse and la Cour Jansen, Jes}},
issn = {{2571-8797}},
keywords = {{waste ochre; biogas; enhanced phosphorus removal; hydrogen sulfide; phosphates precipitation}},
language = {{eng}},
month = {{03}},
number = {{1}},
pages = {{116--116}},
publisher = {{MDPI AG}},
series = {{Clean Technologies}},
title = {{Waste Ochre for Control of Phosphates and Sulfides in Digesters at Wastewater Treatment Plants with Enhanced Biological Phosphorus Removal}},
url = {{https://lup.lub.lu.se/search/files/77009376/cleantechnol_02_00008_v2.pdf}},
doi = {{10.3390/cleantechnol2010008}},
volume = {{2}},
year = {{2020}},
}