Records |
Author |
De Paepe, J.; De Paepe, K.; Gòdia, F.; Rabaey, K.; Vlaeminck, S.E.; Clauwaert, P. |
Title |
Bio-electrochemical COD removal for energy-efficient, maximum and robust nitrogen recovery from urine through membrane aerated nitrification |
Type ![sorted by Type field, ascending order (up)](img/sort_asc.gif) |
A1 Journal article |
Year |
2020 |
Publication |
Water Research |
Abbreviated Journal |
Water Res |
Volume |
185 |
Issue |
|
Pages |
116223 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Resource recovery from source-separated urine can shorten nutrient cycles on Earth and is essential in regenerative life support systems for deep-space exploration. In this study, a robust two-stage, energy-efficient, gravity-independent urine treatment system was developed to transform fresh real human urine into a stable nutrient solution. In the first stage, up to 85% of the COD was removed in a microbial electrolysis cell (MEC), converting part of the energy in organic compounds (27-46%) into hydrogen gas and enabling full nitrogen recovery by preventing nitrogen losses through denitrification in the second stage. Besides COD removal, all urea was hydrolysed in the MEC, resulting in a stream rich in ammoniacal nitrogen and alkalinity, and low in COD. This stream was fed into a membrane-aerated biofilm reactor (MABR) in order to convert the volatile and toxic ammoniacal nitrogen to non-volatile nitrate by nitrification. Bio-electrochemical pre-treatment allowed to recover all nitrogen as nitrate in the MABR at a bulk-phase dissolved oxygen level below 0.1 mg O2 L-1. In contrast, feeding the MABR directly with raw urine (omitting the first stage), at the same nitrogen loading rate, resulted in nitrogen loss (18%) due to denitrification. The MEC and MABR were characterised by very distinct and diverse microbial communities. While (strictly) anaerobic genera, such as Geobacter (electroactive bacteria), Thiopseudomonas, a Lentimicrobiaceae member, Alcaligenes and Proteiniphilum prevailed in the MEC, the MABR was dominated by aerobic genera, including Nitrosomonas (a known ammonium oxidiser), Moheibacter and Gordonia. The two-stage approach yielded a stable nitrate-rich, COD-low nutrient solution, suitable for plant and microalgae cultivation. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000580639800035 |
Publication Date |
2020-07-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0043-1354 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.8 |
Times cited |
|
Open Access |
|
Notes |
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Approved |
Most recent IF: 12.8; 2020 IF: 6.942 |
Call Number |
UA @ admin @ c:irua:170524 |
Serial |
6461 |
Permanent link to this record |
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Author |
De Paepe, J.; Garcia Gragera, D.; Arnau Jimenez, C.; Rabaey, K.; Vlaeminck, S.E.; Gòdia, F. |
Title |
Continuous cultivation of microalgae yields high nutrient recovery from nitrified urine with limited supplementation |
Type ![sorted by Type field, ascending order (up)](img/sort_asc.gif) |
A1 Journal article |
Year |
2023 |
Publication |
Journal of environmental management |
Abbreviated Journal |
|
Volume |
345 |
Issue |
|
Pages |
118500-118510 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Microalgae can play a key role in the bioeconomy, particularly in combination with the valorisation of waste streams as cultivation media. Urine is an example of a widely available nutrient-rich waste stream, and alkaline stabilization and subsequent full nitrification in a bioreactor yields a stable nitrate-rich solution. In this study, such nitrified urine served as a culture medium for the edible microalga Limnospira indica. In batch cultivation, nitrified urine without additional supplements yielded a lower biomass concentration, nutrient uptake and protein content compared to modified Zarrouk medium, as standard medium. To enhance the nitrogen uptake efficiency and biomass production, nitrified urine was supplemented with potentially limiting elements. Limited amounts of phosphorus (36 mg L−1), magnesium (7.9 mg L−1), calcium (12.2 mg L−1), iron (2.0 mg L−1) and EDTA (88.5 mg Na2-EDTA.2H2O L−1) rendered the nitrified urine matrix as effective as modified Zarrouk medium in terms of biomass production (OD750 of 1.2), nutrient uptake (130 mg N L−1) and protein yield (47%) in batch culture. Urine precipitates formed by alkalinisation could in principle supply enough phosphorus, calcium and magnesium, requiring only external addition of iron, EDTA and inorganic carbon. Subsequently, the suitability of supplemented nitrified urine as a culture medium was confirmed in continuous Limnospira cultivation in a CSTR photobioreactor. This qualifies nitrified urine as a valuable and sustainable microalgae growth medium, thereby creating novel nutrient loops on Earth and in Space, i.e., in regenerative life support systems for human deep-space missions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001052880800001 |
Publication Date |
2023-08-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0301-4797 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
8.7 |
Times cited |
|
Open Access |
Not_Open_Access: Available from 03.02.2024 |
Notes |
|
Approved |
Most recent IF: 8.7; 2023 IF: 4.01 |
Call Number |
UA @ admin @ c:irua:199049 |
Serial |
8844 |
Permanent link to this record |