|   | 
Details
   web
Records
Author Zhu, W.; Van Tendeloo, M.; Xie, Y.; Timmer, M.J.; Peng, L.; Vlaeminck, S.E.
Title Storage without nitrite or nitrate enables the long-term preservation of full-scale partial nitritation/anammox sludge Type (up) A1 Journal article
Year 2022 Publication The science of the total environment Abbreviated Journal Sci Total Environ
Volume 806 Issue 3 Pages 151330
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Bioaugmentation with summer harvested sludge during winter could compensate for bacterial activity loss but requires that sludge activity can be restored after storage. This study assesses the effect of temperature and redox adjustment during the storage over 180 days of partial nitritation/anammox (PN/A) granular resp. floccular sludge from potato processing resp. sludge reject water treatment. Anoxic storage conditions (in the presence of nitrite or nitrate and the absence of oxygen) resulted in a loss of 80-100% of the anammox bacteria (AnAOB) activity capacity at 20 degrees C and 4 degrees C, while anaerobic conditions (without oxygen, nitrite, and nitrate) lost only 45-63%. Storage at 20 degrees C was more cost-effective compared to 4 degrees C, and this was confirmed in the sludge reactivation experiment (20 CC). Furthermore, AnAOB activity correlated negatively with the electrical conductivity level (R-2 > 0.85, p < 0.05), so strong salinity increases should be avoided. No significant differences were found in the activity capacity of aerobic ammonia-oxidizing bacteria (AerAOB) under different storage conditions (p > 0.1). The relative abundance of dominant AnAOB (Candidatus Brocadia) and AerAOB genera (Nitrosomonas) remained constant in both sludges. In conclusion, preserving PN/A biomass without cooling and nitrite or nitrate addition proved to be a cost-effective strategy. (C) 2021 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000740216300013 Publication Date 2021-10-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 9.8
Call Number UA @ admin @ c:irua:185447 Serial 7213
Permanent link to this record
 

 
Author Zhu, W.; Van Tendeloo, M.; Alloul, A.; Vlaeminck, S.E.
Title Towards mainstream partial nitritation/anammox in four seasons : feasibility of bioaugmentation with stored summer sludge for winter anammox assistance Type (up) A1 Journal article
Year 2022 Publication Bioresource technology Abbreviated Journal Bioresource Technol
Volume 347 Issue Pages 126619-11
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The strong effect of low temperatures on anammox challenges its mainstream application over the winter in temperate climates. Winter bioaugmentation with stored summer surplus sludge is a potential solution to guarantee sufficient nitrogen removal in winter. Firstly, the systems for which nitrogen removal deteriorated by the temperature decrease (25 °C → 20 °C) could be fully restored bioaugmenting with granules resp. flocs stored for 6 months at 118 resp. 220% of the initial biomass levels. Secondly, the reactivation of these stored sludges was tested in lower temperature systems (15.3 ± 0.4/10.4 ± 0.4 °C). Compared to the activity before storage, between 56% and 41% of the activity of granules was restored within one month, and 41%–32% for flocs. Additionally, 85–87% of granules and 50–53% of flocs were retained in the systems. After reactivation (15.3 ± 0.4/10.4 ± 0.4 °C), a more specialized community was formed (diversity decreased) with Candidatus Brocadia still dominant in terms of relative abundance. Capital and operating expenditures (CAPEX, OPEX) were negligible, representing only 0.19–0.36% of sewage treatment costs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000781730900001 Publication Date 2021-12-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.4 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 11.4
Call Number UA @ admin @ c:irua:185210 Serial 7220
Permanent link to this record
 

 
Author Alloul, A.; Spanoghe, J.; Machado, D.; Vlaeminck, S.E.
Title Unlocking the genomic potential of aerobes and phototrophs for the production of nutritious and palatable microbial food without arable land or fossil fuels Type (up) A1 Journal article
Year 2022 Publication Microbial biotechnology Abbreviated Journal
Volume 15 Issue 1 Pages 6-12
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The increasing world population and living standards urgently necessitate the transition towards a sustainable food system. One solution is microbial protein, i.e. using microbial biomass as alternative protein source for human nutrition, particularly based on renewable electron and carbon sources that do not require arable land. Upcoming green electrification and carbon capture initiatives enable this, yielding new routes to H2, CO2 and CO2-derived compounds like methane, methanol, formic- and acetic acid. Aerobic hydrogenotrophs, methylotrophs, acetotrophs and microalgae are the usual suspects for nutritious and palatable biomass production on these compounds. Interestingly, these compounds are largely un(der)explored for purple non-sulfur bacteria, even though these microbes may be suitable for growing aerobically and phototrophically on these substrates. Currently, selecting the best strains, metabolisms and cultivation conditions for nutritious and palatable microbial food mainly starts from empirical growth experiments, and mostly does not stretch beyond bulk protein. We propose a more target-driven and efficient approach starting from the genome-embedded potential to tuning towards, for instance, essential amino- and fatty acids, vitamins, taste,... Genome-scale metabolic models combined with flux balance analysis will facilitate this, narrowing down experimental variations and enabling to get the most out of the 'best' combinations of strain and electron and carbon sources.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000613868600001 Publication Date 2021-02-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1751-7915 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.7 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5.7
Call Number UA @ admin @ c:irua:176174 Serial 7225
Permanent link to this record
 

 
Author Alloul, A.; Blansaer, N.; Cabecas Segura, P.; Wattiez, R.; Vlaeminck, S.E.; Leroy, B.
Title Dehazing redox homeostasis to foster purple bacteria biotechnology Type (up) A1 Journal article
Year 2023 Publication Trends in biotechnology : regular edition Abbreviated Journal
Volume 41 Issue 1 Pages 106-119
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Purple non-sulfur bacteria (PNSB) show great potential for environmental and industrial biotechnology, producing microbial protein, biohydrogen, polyhydroxyalkanoates (PHAs), pigments, etc. When grown photoheterotrophically, the carbon source is typically more reduced than the PNSB biomass, which leads to a redox imbalance. To mitigate the excess of electrons, PNSB can exhibit several ‘electron sinking’ strategies, such as CO2 fixation, N2 fixation, and H2 and PHA production. The lack of a comprehensive (over)view of these redox strategies is hindering the implementation of PNSB for biotechnology applications. This review aims to present the state of the art of redox homeostasis in phototrophically grown PNSB, presenting known and theoretically expected strategies, and discussing them from stoichiometric, thermodynamic, metabolic, and economic points of view.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000923198400001 Publication Date 2022-07-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1879-3096;0167-7799 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 17.3 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 17.3; 2023 IF: 11.126
Call Number UA @ admin @ c:irua:192944 Serial 7294
Permanent link to this record
 

 
Author Muys, M.; González Cámara, S.J.; Derese, S.; Spiller, M.; Verliefde, A.; Vlaeminck, S.E.
Title Dissolution rate and growth performance reveal struvite as a sustainable nutrient source to produce a diverse set of microbial protein Type (up) A1 Journal article
Year 2023 Publication The science of the total environment Abbreviated Journal
Volume 866 Issue Pages 161172-161179
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract To provide for the globally increasing demand for proteinaceous food, microbial protein (MP) has the potential to become an alternative food or feed source. Phosphorus (P), on the other hand, is a critical raw material whose global reserves are declining. Growing MP on recovered phosphorus, for instance, struvite obtained from wastewater treatment, is a promising MP production route that could supply protein-rich products while handling P scarcity. The aim of this study was to explore struvite dissolution kinetics in different MP media and characterize MP production with struvite as sole P-source. Different operational parameters, including pH, temperature, contact surface area, and ion concentrations were tested, and struvite dissolution rates were observed between 0.32 and 4.7 g P/L/d and a solubility between 0.23 and 2.22 g P-based struvite/L. Growth rates and protein production of the microalgae Chlorella vulgaris and Limnospira sp. (previously known as Arthrospira sp.), and the purple non‑sulfur bacterium Rhodopseudomonas palustris on struvite were equal to or higher than growth on conventional potassium phosphate. For aerobic heterotrophic bacteria, two slow-growing communities showed decreased growth on struvite, while the growth was increased for a third fast-growing one. Furthermore, MP protein content on struvite was always comparable to the one obtained when grown on standard media. Together with the low content in metals and micropollutants, these results demonstrate that struvite can be directly applied as an effective nutrient source to produce fast-growing MP, without any previous dissolution step. Combining a high purity recovered product with an efficient way of producing protein results in a strong environmental win-win.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000922040000001 Publication Date 2022-12-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697; 1879-1026 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 9.8; 2023 IF: 4.9
Call Number UA @ admin @ c:irua:192943 Serial 7297
Permanent link to this record
 

 
Author Xie, Y.; Jia, M.; De Wilde, F.; Daeninck, K.; De Clippeleir, H.; Verstraete, W.; Vlaeminck, S.E.
Title Feasibility of packed-bed trickling filters for partial nitritation/anammox : effects of carrier material, bottom ventilation openings, hydraulic loading rate and free ammonia Type (up) A1 Journal article
Year 2023 Publication Bioresource technology Abbreviated Journal
Volume 373 Issue Pages 128713-128719
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract This study pioneers the feasibility of cost-effective partial nitritation/anammox (PN/A) in packed-bed trickling filters (TFs). Three parallel TFs tested different carrier materials, the presence or absence of bottom ventilation openings, hydraulic loading rates (HLR, 0.4–2.2 m3 m−2 h−1), and free ammonia (FA) levels on synthetic medium. The inexpensive Argex expanded clay was recommended due to the similar nitrogen removal rates as commercially used plastics. Top-only ventilation at an optimum HLR of 1.8 m3 m−2 h−1 could remove approximately 60% of the total nitrogen load (i.e., 300 mg N L-1 d−1, 30 °C) and achieve relatively low NO3–-N accumulation (13%). Likely FA levels of around 1.3–3.2 mg N L-1 suppressed nitratation. Most of the total nitrogen removal took place in the upper third of the reactor, where anammox activity was highest. Provided further optimizations, the results demonstrated TFs are suitable for low-energy shortcut nitrogen removal.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000945892500001 Publication Date 2023-02-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.4 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 11.4; 2023 IF: 5.651
Call Number UA @ admin @ c:irua:193652 Serial 7306
Permanent link to this record
 

 
Author Segura, P.C.; De Meur, Q.; Alloul, A.; Tanghe, A.; Onderwater, R.; Vlaeminck, S.E.; Vande Wouwer, A.; Wattiez, R.; Dewasme, L.; Leroy, B.
Title Preferential photoassimilation of volatile fatty acids by purple non-sulfur bacteria : experimental kinetics and dynamic modelling Type (up) A1 Journal article
Year 2022 Publication Biochemical engineering journal Abbreviated Journal Biochem Eng J
Volume 186 Issue Pages 108547-10
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Purple non-sulfur bacteria (PNSB) are known for their metabolic versatility and thrive as anoxygenic photoheterotrophs. In environmental engineering and resource recovery, cells would grow on mixtures of volatile fatty acids (VFA) generated by anaerobic fermentation of waste streams. In this study, we aim to better understand the behavior of Rhodospirillum rubrum, a model PNSB species, grown using multiple VFA as carbon sources. We highlighted that assimilation of individual VFA follows a sequential pattern. Based on observations in other PNSB, this seems to be specific to isocitrate lyase-lacking organisms. We hypothesized that the inhibition phenomenon could be due to the regulation of the metabolic fluxes in the substrate cycle between acetoacetyl-CoA and crotonyl-CoA. Developed macroscopic dynamic models showed a good predictive capability for substrate competition for every VFA mixture containing acetate, propionate, and/or butyrate. These novel insights provide valuable input for better design and operation of PNSB-based waste treatment solutions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000891992900005 Publication Date 2022-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1369-703x; 1873-295x ISBN Additional Links UA library record; WoS full record
Impact Factor 3.9 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.9
Call Number UA @ admin @ c:irua:192741 Serial 7332
Permanent link to this record
 

 
Author Courtens, E.N.P.; Spieck, E.; Vilchez-Vargas, R.; Bode, S.; Boeckx, P.; Schouten, S.; Jauregui, R.; Pieper, D.H.; Vlaeminck, S.E.; Boon, N.
Title A robust nitrifying community in a bioreactor at 50 degrees C opens up the path for thermophilic nitrogen removal Type (up) A1 Journal article
Year 2016 Publication The ISME journal : multidisciplinary journal of microbial ecology Abbreviated Journal
Volume 10 Issue 9 Pages 2293-2303
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The increasing production of nitrogen-containing fertilizers is crucial to meet the global food demand, yet high losses of reactive nitrogen associated with the food production/consumption chain progressively deteriorate the natural environment. Currently, mesophilic nitrogen-removing microbes eliminate nitrogen from wastewaters. Although thermophilic nitrifiers have been separately enriched from natural environments, no bioreactors are described that couple these processes for the treatment of nitrogen in hot wastewaters. Samples from composting facilities were used as inoculum for the batch-wise enrichment of thermophilic nitrifiers (350 days). Subsequently, the enrichments were transferred to a bioreactor to obtain a stable, high-rate nitrifying process (560 days). The community contained up to 17% ammonia-oxidizing archaea (AOAs) closely related to 'Candidatus Nitrososphaera gargensis', and 25% nitrite-oxidizing bacteria (NOBs) related to Nitrospira calida. Incorporation of C-13-derived bicarbonate into the respective characteristic membrane lipids during nitrification supported their activity as autotrophs. Specific activities up to 198 +/- 10 and 894 +/- 81 mg N g(-1) VSS per day for AOAs and NOBs were measured, where NOBs were 33% more sensitive to free ammonia. The NOBs were extremely sensitive to free nitrous acid, whereas the AOAs could only be inhibited by high nitrite concentrations, independent of the free nitrous acid concentration. The observed difference in product/substrate inhibition could facilitate the development of NOB inhibition strategies to achieve more cost-effective processes such as deammonification. This study describes the enrichment of autotrophic thermophilic nitrifiers from a nutrient-rich environment and the successful operation of a thermophilic nitrifying bioreactor for the first time, facilitating opportunities for thermophilic nitrogen removal biotechnology.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000386664600019 Publication Date 2016-02-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1751-7362 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:138184 Serial 7397
Permanent link to this record
 

 
Author Alloul, A.; Ganigue, R.; Spiller, M.; Meerburg, F.; Cagnetta, C.; Rabaey, K.; Vlaeminck, S.E.
Title Capture-ferment-upgrade : a three-step approach for the valorization of sewage organics as commodities Type (up) A1 Journal article
Year 2018 Publication Environmental science and technology Abbreviated Journal
Volume 52 Issue 12 Pages 6729-6742
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract This critical review outlines a roadmap for the conversion of chemical oxygen demand (COD) contained in sewage to commodities based on three-steps: capture COD as sludge, ferment it to volatile fatty acids (VFA), and upgrade VFA to products. The article analyzes the state-of-the-art of this three step approach and discusses the bottlenecks and challenges. The potential of this approach is illustrated for the European Union's 28 member states (EU-28) through Monte Carlo simulations. High-rate contact stabilization captures the highest amount of COD (66-86 g COD person equivalent(-1) day(-1) in 60% of the iterations). Combined with thermal hydrolysis, this would lead to a VFA-yield of 23-44 g COD person equivalent(-1) day(-1). Upgrading VFA generated by the EU-28 would allow, in 60% of the simulations, for a yearly production of 0.2-2.0 megatonnes of esters, 0.7-1.4 megatonnes of polyhydroxyalkanoates or 0.6-2.2 megatonnes of microbial protein substituting, respectively, 20-273%, 70-140% or 21-72% of their global counterparts (i.e., petrochemical-based esters, bioplastics or fishmeal). From these flows, we conclude that sewage has a strong potential as biorefinery feedstock, although research is needed to enhance capture, fermentation and upgrading efficiencies. These developments need to be supported by economic/environmental analyses and policies that incentivize a more sustainable management of our resources.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000436018900004 Publication Date 2018-05-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-936x; 1520-5851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:151968 Serial 7574
Permanent link to this record
 

 
Author Alloul, A.; Muys, M.; Hertoghs, N.; Kerckhof, F.-M.; Vlaeminck, S.E.
Title Cocultivating aerobic heterotrophs and purple bacteria for microbial protein in sequential photo- and chemotrophic reactors Type (up) A1 Journal article
Year 2021 Publication Bioresource Technology Abbreviated Journal Bioresource Technol
Volume 319 Issue Pages 124192
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Aerobic heterotrophic bacteria (AHB) and purple non-sulfur bacteria (PNSB) are typically explored as two separate types of microbial protein, yet their properties as respectively a bulk and added-value feed ingredient make them appealing for combined use. The feasibility of cocultivation in a sequential photo- and chemotrophic approach was investigated. First, mapping the chemotrophic growth kinetics for four Rhodobacter, Rhodopseudomonas and Rhodospirillum species on different carbon sources showed a preference for fructose (µmax 2.4–3.9 d−1 28 °C; protein 36–59%DW). Secondly, a continuous photobioreactor inoculated with Rhodobacter capsulatus (VFA as C-source) delivered the starter culture for an aerobic batch reactor (fructose as C-source). This two-stage system showed an improved nutritional quality compared to AHB production: higher protein content (45–71%DW), more attractive amino/fatty acid profile and contained up to 10% PNSB. The findings strengthen protein production with cocultures and might enable the implementation of the technology for resource recovery on streams such as wastewater.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000613136600013 Publication Date 2020-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.651 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5.651
Call Number UA @ admin @ c:irua:171766 Serial 7677
Permanent link to this record
 

 
Author Zhang, Q.; De Clippeleir, H.; Su, C.; Al-Omari, A.; Wett, B.; Vlaeminck, S.E.; Murthy, S.
Title Deammonification for digester supernatant pretreated with thermal hydrolysis : overcoming inhibition through process optimization Type (up) A1 Journal article
Year 2016 Publication Applied microbiology and biotechnology Abbreviated Journal
Volume 100 Issue 12 Pages 5595-5606
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The thermal hydrolysis process (THP) has been proven to be an excellent pretreatment step for an anaerobic digester (AD), increasing biogas yield and decreasing sludge disposal. The goal of this work was to optimize deammonification for efficient nitrogen removal despite the inhibition effects caused by the organics present in the THP-AD sludge filtrate (digestate). Two sequencing batch reactors were studied treating conventional digestate and THP-AD digestate, respectively. Improved process control based on higher dissolved oxygen set-point (1 mg O-2/L) and longer aeration times could achieve successful treatment of THP-AD digestate. This increased set-point could overcome the inhibition effect on aerobic ammonium-oxidizing bacteria (AerAOB), potentially caused by particulate and colloidal organics. Moreover, based on the mass balance, anoxic ammonium-oxidizing bacteria (AnAOB) contribution to the total nitrogen removal decreased from 97 +/- A 1 % for conventional to 72 +/- A 5 % for THP-AD digestate treatment, but remained stable by selective AnAOB retention using a vibrating screen. Overall, similar total nitrogen removal rates of 520 +/- A 28 mg N/L/day at a loading rate of 600 mg N/L/day were achieved in the THP-AD reactor compared to the conventional digestate treatment operating at low dissolved oxygen (DO) (0.38 +/- A 0.10 mg O-2/L).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000376456700033 Publication Date 2016-02-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0175-7598; 1432-0614 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:134166 Serial 7755
Permanent link to this record
 

 
Author Vingerhoets, R.; Spiller, M.; De Backer, J.; Adriaens, A.; Vlaeminck, S.E.; Meers, E.
Title Detailed nitrogen and phosphorus flow analysis, nutrient use efficiency and circularity in the agri-food system of a livestock-intensive region Type (up) A1 Journal article
Year 2023 Publication Journal of cleaner production Abbreviated Journal
Volume 410 Issue Pages 137278-13
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The agri-food value chain is a major cause of nitrogen (N) and phosphorus (P) emissions and associated environmental and health impacts. The EU's farm-to-fork strategy (F2F) demands an agri-food value chain approach to reduce nutrient emissions by 50% and fertilizer use by 20%. Substance flow analysis (SFA) is a method that can be applied to study complex systems such as the agri-food chain. A review of 60 SFA studies shows that they often lack detail by not sufficiently distinguishing between nodes, products and types of emissions. The present study aims to assess the added value of detail in SFAs and to illustrate that valuable indicators can be derived from detailed assessments. This aim will be attained by presenting a highly-detailed SFA for the livestock-intensive region of Flanders, Belgium. The SFA distinguishes 40 nodes and 1827 flows that are classified into eight different categories (e.g. by-products, point source emissions) following life cycle methods. Eight novel indicators were calculated, including indicators that assess the N and P recovery potential. Flanders has a low overall nutrient use efficiency (11% N, 18% P). About 55% of the N and 56% of the P embedded in recoverable streams are reused providing 35% and 37% of the total N and P input. Optimized nutrient recycling could replace 45% of N and 48% of P of the external nutrient input, exceeding the target set by the F2F strategy. Detailed accounting for N and P flows and nodes leads to the identification of more recoverable streams and larger N and P flows. More detailed flow accounting is a prerequisite for the quantification of technological intervention options. Future research should focus on including concentration and quality as a parameter in SFAs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000991013600001 Publication Date 2023-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0959-6526 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.1 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 11.1; 2023 IF: 5.715
Call Number UA @ admin @ c:irua:196227 Serial 7770
Permanent link to this record
 

 
Author Vanderkerckhove, T.G.L.; Kerckhof, F.-M.; De Mulder, C.; Vlaeminck, S.E.; Boon, N.
Title Determining stoichiometry and kinetics of two thermophilic nitrifying communities as a crucial step in the development of thermophilic nitrogen removal Type (up) A1 Journal article
Year 2019 Publication Water research Abbreviated Journal
Volume 156 Issue Pages 34-45
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Nitrification and denitrification, the key biological processes for thermophilic nitrogen removal, have separately been established in bioreactors at 50 °C. A well-characterized set of kinetic parameters is essential to integrate these processes while safeguarding the autotrophs performing nitrification. Knowledge on thermophilic nitrifying kinetics is restricted to isolated or highly enriched batch cultures, which do not represent bioreactor conditions. This study characterized the stoichiometry and kinetics of two thermophilic (50 °C) nitrifying communities. The most abundant ammonia oxidizing archaea (AOA) were related to the Nitrososphaera genus, clustering relatively far from known species Nitrososphaera gargensis (95.5% 16S rRNA gene sequence identity). The most abundant nitrite oxidizing bacteria (NOB) were related to Nitrospira calida (97% 16S rRNA gene sequence identity). The nitrification biomass yield was 0.200.24 g VSS g−1 N, resulting mainly from a high AOA yield (0.160.20 g VSS g−1 N), which was reflected in a high AOA abundance in the community (5776%) compared to NOB (511%). Batch-wise determination of decay rates (AOA: 0.230.29 d−1; NOB: 0.320.43 d−1) rendered an overestimation compared to in situ estimations of overall decay rate (0.0260.078 d−1). Possibly, the inactivation rate rather than the actual decay rate was determined in batch experiments. Maximum growth rates of AOA and NOB were 0.120.15 d−1 and 0.130.33 d−1 respectively. NOB were susceptible to nitrite, opening up opportunities for shortcut nitrogen removal. However, NOB had a similar growth rate and oxygen affinity (0.150.55 mg O2 L−1) as AOA and were resilient towards free ammonia (IC50 > 16 mg NH3-N L−1). This might complicate NOB outselection using common practices to establish shortcut nitrogen removal (SRT control; aeration control; free ammonia shocks). Overall, the obtained insights can assist in integrating thermophilic conversions and facilitate single-sludge nitrification/denitrification.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000466618400004 Publication Date 2019-03-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0043-1354; 1879-2448 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:158226 Serial 7798
Permanent link to this record
 

 
Author Saha, S.; Badhe, N.; Seuntjens, D.; Vlaeminck, S.E.; Biswas, R.; Nandy, T.
Title Effective carbon and nutrient treatment solutions for mixed domestic-industrial wastewater in India Type (up) A1 Journal article
Year 2015 Publication Water science and technology Abbreviated Journal
Volume 72 Issue 4 Pages 651-657
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The present study evaluates effectiveness of up-flow anaerobic sludge blanket (UASB) reactor followed by two post-anaerobic treatment options, namely free-surface, up-flow constructed wetland (FUP-CW) and oxygen-limited anaerobic nitrification/denitrification (OLAND) processes in treating sewage from the peri-urban areas in India receiving illegal industrial infiltrations. The UASB studies yielded robust results towards fluctuating strength of sewage and consistently removed 87-98% chemical oxygen demand (COD) at a hydraulic retention time of 1.5-2 d. The FUP-CW removed 68.5 +/- 13% COD, 68 +/- 3% NH4+-N, 38 +/- 5% PO43--P, 97.6 +/- 5% suspended particles and 97 +/- 13% fecal coliforms. Nutrient removal was found to be limiting in FUP-CW, especially in winter. Nitrogen removal in the OLAND process were 100 times higher than the FUP-CW process. Results show that UASB followed by FUP-CW can be an excellent, decentralized sewage treatment option, except during winter when nutrient removal is limited in FUP-CW. Hence, the study proposes bio-augmentation of FUP-CW with OLAND biomass for overall improvement in the performance of UASB followed by FUP-CW process.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000359387200019 Publication Date 2015-08-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0273-1223; 1996-9732 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:127775 Serial 7840
Permanent link to this record
 

 
Author Sui, Y.; Vlaeminck, S.E.
Title Effects of salinity, pH and growth phase on the protein productivity by Dunaliella salina Type (up) A1 Journal article
Year 2019 Publication Journal of chemical technology and biotechnology Abbreviated Journal
Volume 94 Issue 4 Pages 1032-1040
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract BACKGROUND Microalgae have long been adopted for use as human food, animal feed and high‐value products. For carotenogenesis, Dunaliella salina is one of the most studied microalgae, yet its protein synthesis has been limitedly reported. In this study, D. salina was cultivated at different NaCl and pH levels to optimize its protein productivity. RESULTS The biomass protein content followed an increasedecrease pattern throughout the growth phases, with a maximum in the exponential phase (6080% over ash‐free dry weight). Adversely, the biomass pigment contents were at relatively stable levels (around 0.5% carotenoids, 1.3% chlorophyll a and 0.5% chlorophyll b over ash‐free dry weight). Among the tested conditions (13 mol L−1 salinity, pH 7.59.5), the highest protein productivity (43.5 mg L−1 day−1) was achieved at 2 mol L−1 salinity and pH 7.5 during the exponential phase, which surpassed others by 1697%. Additionally, table salts were tested to be equivalent and cost‐efficient salt sources for the growth medium. CONCLUSION This study highlighted the suitability of D. salina as a protein source, providing guidelines for 70% cheaper medium formulation in the lab and for maximum protein productivity at larger scale.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000461237300004 Publication Date 2018-10-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0268-2575; 1097-4660 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:157955 Serial 7849
Permanent link to this record
 

 
Author De Paepe, J.; Clauwaert, P.; Gritti, M.C.; Ganigue, R.; Sas, B.; Vlaeminck, S.E.; Rabaey, K.
Title Electrochemical in situ pH control enables chemical-free full urine nitrification with concomitant nitrate extraction Type (up) A1 Journal article
Year 2021 Publication Environmental Science & Technology Abbreviated Journal Environ Sci Technol
Volume 55 Issue 12 Pages 8287-8298
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Urine is a valuable resource for nutrient recovery. Stabilization is, however, recommended to prevent urea hydrolysis and the associated risk for ammonia volatilization, uncontrolled precipitation, and malodor. This can be achieved by alkalinization and subsequent biological conversion of urea and ammonia into nitrate (nitrification) and organics into CO2. Yet, without pH control, the extent of nitrification is limited as a result of insufficient alkalinity. This study explored the feasibility of an integrated electrochemical cell to obtain on-demand hydroxide production through water reduction at the cathode, compensating for the acidification caused by nitritation, thereby enabling full nitrification. To deal with the inherent variability of the urine influent composition and bioprocess, the electrochemical cell was steered via a controller, modulating the current based on the pH in the bioreactor. This provided a reliable and innovative alternative to base addition, enabling full nitrification while avoiding the use of chemicals, the logistics associated with base storage and dosing, and the associated increase in salinity. Moreover, the electrochemical cell could be used as an in situ extraction and concentration technology, yielding an acidic concentrated nitrate-rich stream. The make-up of the end product could be tailored by tweaking the process configuration, offering versatility for applications on Earth and in space.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000663939900052 Publication Date 2021-06-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-936x; 1520-5851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.198 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 6.198
Call Number UA @ admin @ c:irua:179779 Serial 7862
Permanent link to this record
 

 
Author Courtens, E.N.P.; Vandekerckhove, T.; Prat, D.; Vilchez-Vargas, R.; Vital, M.; Pieper, D.H.; Meerbergen, K.; Lievens, B.; Boon, N.; Vlaeminck, S.E.
Title Empowering a mesophilic inoculum for thermophilic nitrification : growth mode and temperature pattern as critical proliferation factors for archaeal ammonia oxidizers Type (up) A1 Journal article
Year 2016 Publication Water research Abbreviated Journal
Volume 92 Issue Pages 94-103
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Cost-efficient biological treatment of warm nitrogenous wastewaters requires the development of thermophilic nitrogen removal processes. Only one thermophilic nitrifying bioreactor was described so far, achieving 200 mg N L-1 d-1 after more than 300 days of enrichment from compost samples. From the practical point of view in which existing plants would be upgraded, however, a more time-efficient development strategy based on mesophilic nitrifying sludge is preferred. This study evaluated the adaptive capacities of mesophilic nitrifying sludge for two linear temperature increase patterns (non-oscillating vs. oscillating), two different slopes (0.25 vs. 0.08 °C d-1) and two different reactor types (floc vs. biofilm growth). The oscillating temperature pattern (0.25 °C d-1) and the moving bed biofilm reactor (0.08 °C d-1) could not reach nitrification at temperatures higher than 46°C. However, nitrification rates up to 800 mg N L-1 d-1 and 150 mg N g-1 volatile suspended solids d-1 were achieved at a temperature as high as 49°C by imposing the slowest linear temperature increase to floccular sludge. Microbial community analysis revealed that this successful transition was related with a shift in ammonium oxidizing archaea dominating ammonia oxidizing bacteria, while for nitrite oxidation Nitrospira spp. was constantly more abundant than Nitrobacter spp.. This observation was accompanied with an increase in observed sludge yield and a shift in maximal optimum temperature, determined with ex-situ temperature sensitivity measurements, predicting an upcoming reactor failure at higher temperature. Overall, this study achieved nitrification at 49°C within 150 days by gradual adaptation of mesophilic sludge, and showed that ex-situ temperature sensitivity screening can be used to monitor and steer the transition process.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000371555200011 Publication Date 2016-01-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0043-1354; 1879-2448 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:130444 Serial 7900
Permanent link to this record
 

 
Author Seuntjens, D.; Bundervoet, B.L.M.; Mollen, H.; De Mulder, C.; Wypkema, E.; Verliefde, A.; Nopens, I.; Colsen, J.G.M.; Vlaeminck, S.E.
Title Energy efficient treatment of A-stage effluent : pilot-scale experiences with short-cut nitrogen removal Type (up) A1 Journal article
Year 2016 Publication Water science and technology Abbreviated Journal
Volume 73 Issue 9 Pages 2150-2158
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000376285300013 Publication Date 2016-02-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0273-1223; 1996-9732 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:130442 Serial 7908
Permanent link to this record
 

 
Author Sui, Y.; Muys, M.; Van de Waal, D.; D'Adamo, S.; Vermeir, P.; Fernandes, T.V.; Vlaeminck, S.E.
Title Enhancement of co-production of nutritional protein and carotenoids in Dunaliella salina using a two-phase cultivation assisted by nitrogen level and light intensity Type (up) A1 Journal article
Year 2019 Publication Bioresource technology Abbreviated Journal
Volume 287 Issue Pages 121398
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Microalga Dunaliella salina is known for its carotenogenesis. At the same time, it can also produce high-quality protein. The optimal conditions for D. salina to co-produce intracellular pools of both compounds, however, are yet unknown. This study investigated a two-phase cultivation strategy to optimize combined high-quality protein and carotenoid production of D. salina. In phase-one, a gradient of nitrogen concentrations was tested. In phase-two, effects of nitrogen pulse and high illumination were tested. Results reveal optimized protein quantity, quality (expressed as essential amino acid index EAAI) and carotenoids content in a two-phase cultivation, where short nitrogen starvation in phase-one was followed by high illumination during phase-two. Adopting this strategy, productivities of protein, EAA and carotenoids reached 22, 7 and 3 mg/L/d, respectively, with an EAAI of 1.1. The quality of this biomass surpasses FAO/WHO standard for human nutrition, and the observed level of β-carotene presents high antioxidant pro-vitamin A activity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000469414500008 Publication Date 2019-04-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:159661 Serial 7916
Permanent link to this record
 

 
Author De Cocker, P.; Bessiere, Y.; Hernandez-Raquet, G.; Dubos, S.; Mozo, I.; Gaval, G.; Caligaris, M.; Barillon, B.; Vlaeminck, S.E.; Sperandio, M.
Title Enrichment and adaptation yield high anammox conversion rates under low temperatures Type (up) A1 Journal article
Year 2018 Publication Bioresource technology Abbreviated Journal
Volume 250 Issue Pages 505-512
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract This study compared two anammox sequencing batch reactors (SBR) for one year. SBRconstantT was kept at 30 °C while temperature in SBRloweringT was decreased step-wise from 30 °C to 20 °C and 15 °C followed by over 140 days at 12.5 °C and 10 °C. High retention of anammox bacteria (AnAOB) and minimization of competition with AnAOB were key. 5-L anoxic reactors with the same inoculum were fed synthetic influent containing 25.9 mg NH4+-N/L and 34.1 mg NO2−-N/L (no COD). Specific ammonium removal rates continuously increased in SBRconstantT, reaching 785 mg NH4+-N/gVSS/d, and were maintained in SBRloweringT, reaching 82.2 and 91.8 mg NH4+-N/gVSS/d at 12.5 and 10 °C respectively. AnAOB enrichment (increasing hzsA and 16S rDNA gene concentrations) and adaptation (shift from Ca. Brocadia to Ca. Kuenenia in SBRloweringT) contributed to these high rates. Rapidly settling granules developed, with average diameters of 1.2 (SBRconstantT) and 1.6 mm (SBRloweringT). Results reinforce the potential of anammox for mainstream applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430740000062 Publication Date 2017-11-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:148998 Serial 7920
Permanent link to this record
 

 
Author Cerruti, M.; Stevens, B.; Ebrahimi, S.; Alloul, A.; Vlaeminck, S.E.; Weissbrodt, D.G.
Title Enrichment and aggregation of purple non-sulfur bacteria in a mixed-culture sequencing-batch photobioreactor for biological nutrient removal from wastewater Type (up) A1 Journal article
Year 2020 Publication Frontiers in Bioengineering and Biotechnology Abbreviated Journal
Volume 8 Issue Pages 557234
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Mixed-culture biotechnologies are widely used to capture nutrients from wastewater. Purple non-sulfur bacteria (PNSB), a guild of anoxygenic photomixotrophic organisms, rise interest for their ability to directly assimilate nutrients in the biomass. One challenge targets the aggregation and accumulation of PNSB biomass to separate it from the treated water. Our aim was to enrich and produce a concentrated, fast-settling PNSB biomass with high nutrient removal capacity in a 1.5-L, stirred-tank, anaerobic sequencing-batch photobioreactor (SBR). PNSB were rapidly enriched after inoculation with activated sludge at 0.1 gVSS L–1 in a first batch of 24 h under continuous irradiance of infrared (IR) light (>700 nm) at 375 W m–2, with Rhodobacter reaching 54% of amplicon sequencing read counts. SBR operations with decreasing hydraulic retention times (48 to 16 h, i.e., 1–3 cycles d–1) and increasing volumetric organic loading rates (0.2–1.3 kg COD d–1 m–3) stimulated biomass aggregation, settling, and accumulation in the system, reaching as high as 3.8 g VSS L–1. The sludge retention time (SRT) increased freely from 2.5 to 11 days. Acetate, ammonium, and orthophosphate were removed up to 96% at a rate of 1.1 kg COD d–1 m–3, 77% at 113 g N d–1 m–3, and 73% at 15 g P d–1 m–3, respectively, with COD:N:P assimilation ratio of 100:6.7:0.9 m/m/m. SBR regime shifts sequentially selected for Rhodobacter (90%) under shorter SRT and non-limiting concentration of acetate during reaction phases, for Rhodopseudomonas (70%) under longer SRT and acetate limitation during reaction, and Blastochloris (10%) under higher biomass concentrations, underlying competition for substrate and photons in the PNSB guild. With SBR operations we produced a fast-settling biomass, highly (>90%) enriched in PNSB. A high nutrient removal was achieved by biomass assimilation, reaching the European nutrient discharge limits. We opened further insights on the microbial ecology of PNSB-based processes for water resource recovery.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000603626100001 Publication Date 2021-06-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296-4185 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.7 Times cited Open Access
Notes Approved Most recent IF: 5.7; 2020 IF: NA
Call Number UA @ admin @ c:irua:174085 Serial 7921
Permanent link to this record
 

 
Author Coppens, J.; Meers, E.; Boon, N.; Buysse, J.; Vlaeminck, S.E.
Title Follow the N and P road : high-resolution nutrient flow analysis of the Flanders region as precursor for sustainable resource management Type (up) A1 Journal article
Year 2016 Publication Resources, conservation and recycling Abbreviated Journal
Volume 115 Issue Pages 9-21
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Resource-efficient nutrient management is key to secure food production in the context of a growing global population, rising resource scarcity and increasing pressure on the environment. To map the potential towards increasing nutrient use efficiencies and reduce environmental losses, a high-resolution insight of the nitrogen (N) and phosphorus (P) nutrient streams is pivotal. In this study, a substance flow analysis for N and P is presented for the nutrient intensive region of Flanders (6,211,065 inhabitants) in Belgium for the year 2009. A set of 160 nutrient fluxes was quantified throughout 21 economic and environmental compartments, with a particular focus on 10 waste management processes. A total nutrient load of 20 kg N cap(-1) yr(-1) (ca. 73% to the air and 28% to surface waters) and 0.53 kg P cap(-1) yr(-1) (to surface waters) is emitted to the environment; with crop and livestock production as the main contributors (49% of N and 36% of P). The food supply chain revealed a fertilizer-to-consumer efficiency of 14% for N as well as for P, with important losses embedded in waste streams such as excess manure. Advanced manure and waste processing facilities nevertheless offer the opportunity for enhanced nutrient recycling to increase the nutrient use efficiencies and reduce the dependency of inorganic fertilizers. (C) 2016 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000384852500002 Publication Date 2016-08-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-3449 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:137229 Serial 7977
Permanent link to this record
 

 
Author Kerckhof, F.-M.; Sakarika, M.; Van Giel, M.; Muys, M.; Vermeir, P.; De Vrieze, J.; Vlaeminck, S.E.; Rabaey, K.; Boon, N.
Title From biogas and hydrogen to microbial protein through co-cultivation of methane and hydrogen oxidizing bacteria Type (up) A1 Journal article
Year 2021 Publication Frontiers in Bioengineering and Biotechnology Abbreviated Journal
Volume 9 Issue Pages 733753
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Increasing efforts are directed towards the development of sustainable alternative protein sources among which microbial protein (MP) is one of the most promising. Especially when waste streams are used as substrates, the case for MP could become environmentally favorable. The risks of using organic waste streams for MP production–the presence of pathogens or toxicants–can be mitigated by their anaerobic digestion and subsequent aerobic assimilation of the (filter-sterilized) biogas. Even though methane and hydrogen oxidizing bacteria (MOB and HOB) have been intensively studied for MP production, the potential benefits of their co-cultivation remain elusive. Here, we isolated a diverse group of novel HOB (that were capable of autotrophic metabolism), and co-cultured them with a defined set of MOB, which could be grown on a mixture of biogas and H2/O2. The combination of MOB and HOB, apart from the CH4 and CO2 contained in biogas, can also enable the valorization of the CO2 that results from the oxidation of methane by the MOB. Different MOB and HOB combinations were grown in serum vials to identify the best-performing ones. We observed synergistic effects on growth for several combinations, and in all combinations a co-culture consisting out of both HOB and MOB could be maintained during five days of cultivation. Relative to the axenic growth, five out of the ten co-cultures exhibited 1.1–3.8 times higher protein concentration and two combinations presented 2.4–6.1 times higher essential amino acid content. The MP produced in this study generally contained lower amounts of the essential amino acids histidine, lysine and threonine, compared to tofu and fishmeal. The most promising combination in terms of protein concentration and essential amino acid profile was Methyloparacoccus murrelli LMG 27482 with Cupriavidus necator LMG 1201. Microbial protein from M. murrelli and C. necator requires 27–67% less quantity than chicken, whole egg and tofu, while it only requires 15% more quantity than the amino acid-dense soybean to cover the needs of an average adult. In conclusion, while limitations still exist, the co-cultivation of MOB and HOB creates an alternative route for MP production leveraging safe and sustainably-produced gaseous substrates.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000697897900001 Publication Date 2021-09-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296-4185 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:180591 Serial 7985
Permanent link to this record
 

 
Author Grunert, O.; Reheul, D.; Van Labeke, M.-C.; Perneel, M.; Hernandez-Sanabria, E.; Vlaeminck, S.E.; Boon, N.
Title Growing media constituents determine the microbial nitrogen conversions in organic growing media for horticulture Type (up) A1 Journal article
Year 2016 Publication Microbial Biotechnology Abbreviated Journal
Volume 9 Issue 3 Pages 389-399
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Vegetables and fruits are an important part of a healthy food diet, however, the eco-sustainability of the production of these can still be significantly improved. European farmers and consumers spend an estimated Euro15.5 billion per year on inorganic fertilizers and the production of N-fertilizers results in a high carbon footprint. We investigated if fertilizer type and medium constituents determine microbial nitrogen conversions in organic growing media and can be used as a next step towards a more sustainable horticulture. We demonstrated that growing media constituents showed differences in urea hydrolysis, ammonia and nitrite oxidation and in carbon dioxide respiration rate. Interestingly, mixing of the growing media constituents resulted in a stimulation of the function of the microorganisms. The use of organic fertilizer resulted in an increase in amoA gene copy number by factor 100 compared to inorganic fertilizers. Our results support our hypothesis that the activity of the functional microbial community with respect to nitrogen turnover in an organic growing medium can be improved by selecting and mixing the appropriate growing media components with each other. These findings contribute to the understanding of the functional microbial community in growing media and its potential role towards a more responsible horticulture.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000374662600009 Publication Date 2016-03-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1751-7907 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:133617 Serial 8013
Permanent link to this record
 

 
Author Meerburg, F.A.; Vlaeminck, S.E.; Roume, H.; Seuntjens, D.; Pieper, D.H.; Jauregui, R.; Vilchez-Vargas, R.; Boon, N.
Title High-rate activated sludge communities have a distinctly different structure compared to low-rate sludge communities, and are less sensitive towards environmental and operational variables Type (up) A1 Journal article
Year 2016 Publication Water research Abbreviated Journal
Volume 100 Issue Pages 137-145
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract High-rate activated sludge processes allow for the recovery of organics and energy from wastewaters. These systems are operated at a short sludge retention time and high sludge-specific loading rates, which results in a higher sludge yield and better digestibility than conventional, low-rate activated sludge. Little is known about the microbial ecology of high-rate systems. In this work, we address the need for a fundamental understanding of how high-rate microbial communities differ from low-rate communities. We investigated the high-rate and low-rate communities in a sewage treatment plant in relation to environmental and operational variables over a period of ten months. We demonstrated that (1) high-rate and low-rate communities are distinctly different in terms of richness, evenness and composition, (2) high-rate community dynamics are more variable and less shaped by deterministic factors compared to low-rate communities, (3) sub-communities of continuously core and transitional members are more shaped by deterministic factors than the continuously rare members, both in high-rate and low-rate communities, and (4) high-rate community members showed a co-occurrence pattern similar to that of low-rate community members, but were less likely to be correlated to environmental and operational variables. These findings provide a basis for further optimization of high-rate systems, in order to facilitate resource recovery from wastewater.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000378448800014 Publication Date 2016-05-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0043-1354; 1879-2448 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:139914 Serial 8035
Permanent link to this record
 

 
Author Cagnetta, C.; Saerens, B.; Meerburg, F.A.; Decru, S.O.; Broeders, E.; Menkveld, W.; Vandekerckhove, T.G.L.; De Vrieze, J.; Vlaeminck, S.E.; Verliefde, A.R.D.; De Gusseme, B.; Weemaes, M.; Rabaey, K.
Title High-rate activated sludge systems combined with dissolved air flotation enable effective organics removal and recovery Type (up) A1 Journal article
Year 2019 Publication Bioresource technology Abbreviated Journal
Volume 291 Issue Pages 121833
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract High-rate activated sludge (HRAS) systems typically generate diluted sludge which requires further thickening prior to anaerobic digestion (AD), besides the need to add considerable coagulant and flocculant for the solids separation. As an alternative to conventional gravitational settling, a dissolved air flotation (DAF) unit was coupled to a HRAS system or a high-rate contact stabilization (HiCS) system. The HRAS-DAF system allowed up to 78% removal of the influent solids, and the HiCS-DAF 67%. Both were within the range of values typically obtained for HRAS-settler systems, albeit at a lower chemical requirement. The separated sludge had a high concentration of up to 47 g COD L−1, suppressing the need of further thickening before AD. Methanation tests showed a biogas yield of up to 68% on a COD basis. The use of a DAF separation system can thus enable direct organics removal at high sludge concentration and with low chemical needs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000480326200048 Publication Date 2019-07-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:161098 Serial 8036
Permanent link to this record
 

 
Author Seuntjens, D.; Carvajal-Arroyo, J.M.; Ruopp, M.; Bunse, P.; De Mulder, C.P.; Lochmatter, S.; Agrawal, S.; Boon, N.; Lackner, S.; Vlaeminck, S.E.
Title High-resolution mapping and modeling of anammox recovery from recurrent oxygen exposure Type (up) A1 Journal article
Year 2018 Publication Water research Abbreviated Journal
Volume 144 Issue Pages 522-531
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Oxygen inhibits anammox, a bioconversion executed by anoxic ammonium oxidizing bacteria (AnAOB). Nonetheless, oxygen is mostly found in the proximity of AnAOB in nitrogen removal applications, being a substrate for nitritation. The experiments performed to date were mostly limited to batch activity tests where AnAOB activity is estimated during oxygen exposure. However, little attention has been paid to the recovery and reversibility of activity following aerobic conditions, of direct relevance for bioreactor operation. In this work, anoxic and autotrophic reactor cultivation at 20 degrees C yielded an enriched microbial community in AnAOB, consisting for 75% of a member of the genus Brocadia. High-resolution kinetic data were obtained with online ammonium measurements and further processed with a newly developed Python data pipeline. The experimentally obtained AnAOB response showed complete inhibition until micro-aerobic conditions were reached again (<0.02 mg O-2 L-1). After oxygen inhibition, AnAOB recovered gradually, with recovery times of 5-37 h to reach a steady-state activity, dependent on the perceived inhibition. The recovery immediately after inhibition was lowest when exposed to higher oxygen concentrations (range: 0.5-8 mg O-2 L-1) with long contact times (range: 9-24 h). The experimental data did not fit well with a conventional 'instant recovery' Monod-type inhibition model. Yet, the fit greatly improved by incorporating a dynamic growth rate formula accurately describing gradual activity recovery. With the upgraded model, long-term kinetic simulations for partial nitritation/anammox (PN/A) with intermittent aeration showed a decrease in growth rate compared to the instant recovery mode. These results indicate that recovery of AnAOB after oxygen exposure was previously overlooked. It is recommended to account for this effect in the intensification of partial nitritation/anammox. (C) 2018 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000447569300051 Publication Date 2018-07-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0043-1354; 1879-2448 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:152910 Serial 8037
Permanent link to this record
 

 
Author Muys, M.; Sui, Y.; Schwaiger, B.; Lesueur, C.; Vandenheuvel, D.; Vermeir, P.; Vlaeminck, S.E.
Title High variability in nutritional value and safety of commercially available Chlorella and Spirulina biomass indicates the need for smart production strategies Type (up) A1 Journal article
Year 2019 Publication Bioresource technology Abbreviated Journal
Volume 275 Issue Pages 247-257
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Microalgal biomass production is a resource-efficient answer to the exponentially increasing demand for protein, yet variability in biomass quality is largely unexplored. Nutritional value and safety were determined for Chlorella and Spirulina biomass from different producers, production batches and the same production batch. Chlorella presented a similar protein content (47 ± 8%) compared to Spirulina (48 ± 4%). However, protein quality, expressed as essential amino acid index, and digestibility were lower for Chlorella (1.1 ± 0.1 and 51 ± 9%, respectively) compared to Spirulina (1.3 ± 0.1 and 61 ± 4%, respectively). Generally, variability was lower between batches and within a batch. Heavy metals, pesticides, mycotoxins, antibiotics and nitrate did not violate regulatory limits, while polycyclic aromatic hydrocarbon levels exceeded the norm for some samples, indicating the need for continuous monitoring. This first systematic screening of commercial microalgal biomass revealed a high nutritional variability, necessitating further optimization of cultivation and post-processing conditions. Based on price and quality, Spirulina was preferred above Chlorella.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000456405000030 Publication Date 2018-12-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:155979 Serial 8040
Permanent link to this record
 

 
Author Han, M.; De Clippeleir, H.; Al-Omari, A.; Wett, B.; Vlaeminck, S.E.; Bott, C.; Murthy, S.
Title Impact of carbon to nitrogen ratio and aeration regime on mainstream deammonification Type (up) A1 Journal article
Year 2016 Publication Water science and technology Abbreviated Journal
Volume 74 Issue 2 Pages 375-384
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract While deammonification of high-strength wastewater in the sludge line of sewage treatment plants has become well established, the potential cost savings spur the development of this technology for mainstream applications. This study aimed at identifying the effect of aeration and organic carbon on the deammonification process. Two 10 L sequencing bath reactors with different aeration frequencies were operated at 25 degrees C. Real wastewater effluents from chemically enhanced primary treatment and high-rate activated sludge process were fed into the reactors with biodegradable chemical oxygen demand/nitrogen (bCOD/N) of 2.0 and 0.6, respectively. It was found that shorter aerobic solids retention time (SRT) and higher aeration frequency gave more advantages for aerobic ammonium-oxidizing bacteria (AerAOB) than nitrite oxidizing bacteria (NOB) in the system. From the kinetics study, it is shown that the affinity for oxygen is higher for NOB than for AerAOB, and higher dissolved oxygen set-point could decrease the affinity of both AerAOB and NOB communities. After 514 days of operation, it was concluded that lower organic carbon levels enhanced the activity of anoxic ammonium-oxidizing bacteria (AnAOB) over denitrifiers. As a result, the contribution of AnAOB to nitrogen removal increased from 40 to 70%. Overall, a reasonably good total removal efficiency of 66% was reached under a low bCOD/N ratio of 2.0 after adaptation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000380765500011 Publication Date 2016-04-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0273-1223; 1996-9732 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:135032 Serial 8062
Permanent link to this record
 

 
Author Sfez, S.; De Meester, S.; Vlaeminck, S.E.; Dewulf, J.
Title Improving the resource footprint evaluation of products recovered from wastewater : a discussion on appropriate allocation in the context of circular economy Type (up) A1 Journal article
Year 2019 Publication Resources, conservation and recycling Abbreviated Journal
Volume 148 Issue Pages 132-144
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Shifting from a linear to a circular economy has consequences on how the sustainability of products is assessed. This is the case for products recovered from resources such as sewage sludge. The “zero-burden” assumption is commonly used in Life Cycle Assessment and considers that waste streams are burden-free, which becomes debatable when comparing waste-based with virgin material-based products in the context of the growing circular economy. If waste streams are considered as resources rather than waste, upstream burdens should be partly allocated to all products to allow a fair comparison with their virgin material-based equivalents. In this paper, five allocation approaches are applied to allocate the resource use of upstream processes (consumer goods production) to products recovered from the processing of sewage sludge in the Netherlands, which produces biogas, (phosphorus-based) chemicals and building materials. Except for the approach which allocates 100% of the impact from resource recovery processes to the preceding consumer goods, the allocation approaches show a resource use 27 to 80% higher than with the “zero-burden” assumption. In this particular case, using these allocation approaches is likely to find little support from recyclers. The producers of household products, recyclers and policy makers should find a consensus to consider the shift from a linear to a circular economy in sustainability assessment studies while avoiding discouraging the implementation of recovery technologies. This paper suggests starting the discussion with the approach which allocates the impacts from upstream processes degressively to the downstream products as it best translates the industrial ecology principles.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000472242800012 Publication Date 2019-05-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-3449 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:159887 Serial 8072
Permanent link to this record