Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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Comparative life cycle assessment of real pilot reactors for microalgae cultivation in different seasons
Pérez-López, Paula ; Vree, Jeroen H. de; Feijoo, Gumersindo ; Bosma, Rouke ; Barbosa, Maria J. ; Moreira, María Teresa ; Wijffels, René H. ; Boxtel, Anton J.B. van; Kleinegris, Dorinde M.M. - \ 2017
Applied energy 205 (2017). - ISSN 0306-2619 - p. 1151 - 1164.
Life cycle assessment (LCA) - Microalgae cultivation - Open raceway pond - Pilot plant - Tubular photobioreactor - Weather variations

Microalgae are promising natural resources for biofuels, chemical, food and feed products. Besides their economic potential, the environmental sustainability must be examined. Cultivation has a significant environmental impact that depends on reactor selection and operating conditions. To identify the main environmental bottlenecks for scale-up to industrial facilities this study provides a comparative life cycle assessment (LCA) of open raceway ponds and tubular photobioreactors at pilot scale. The results are based on experimental data from real pilot plants operated in summer, fall and winter at AlgaePARC (Wageningen, The Netherlands). The energy consumption for temperature regulation presented the highest environmental burden. The production of nutrients affected some categories. Despite limited differences compared to the vertical system, the horizontal PBR was found the most efficient in terms of productivity and environmental impact. The ORP was, given the Dutch climatic conditions, only feasible under summer operation. The results highlight the relevance of LCA as a tool for decision-making in process design. Weather conditions and availability of sources for temperature regulation were identified as essential factors for the selection of geographic locations and for microalgal cultivation systems based on environmental criteria. Simulation of large-scale reactors with optimized temperature regulation systems lead to environmental improvements and energy demand reductions ranging from 17% up to 90% for systems operated in favorable summer conditions.

Outdoor production of microalgae
Vree, Jeroen H. de - \ 2016
University. Promotor(en): Rene Wijffels, co-promotor(en): Rouke Bosma; Maria Barbosa. - Wageningen : Wageningen University - ISBN 9789462578784 - 179
algae - algae culture - design - bioreactors - photobioreactors - modeling - algen - algenteelt - ontwerp - bioreactoren - fotobioreactoren - modelleren

This thesis describes the production of microalgae under outdoor conditions, for this research was done at pilot scale. Microalgae are an interesting alternative to currently used sources for bulk commodities as food, feed and chemicals. Research activities within the field are shattered; different reactor systems are investigated at different locations while the systems are operated with different species. The shattered activities prevent a consensus to be reached within the scientific community on the reactor system that has the best performance. Selecting the best performing reactor system will bring the algae industry to the next level. In this PhD thesis different reactor designs were compared on a single location while using the same species in all systems. For this purpose the microalgal pilot facility AlgaePARC (Production And Research Centre) was designed and is described within this thesis. Followed by a comparison of the different reactor designs while using for each comparison a different operational strategy. Operational strategies investigated were chemostat operation and turbidostat operation. During chemostat operation a fixed daily dilution rate is applied to the reactor system, biomass concentrations vary as a result of the applied dilution rate and light conditions. During turbidostat operation the biomass concentration within a system is fixed and as a result of the set biomass concentration and light conditions the daily dilution rate varies. Findings from laboratory scale to pilot scale experiments are extrapolated to indicate the potential of microalgae production at a commercial scale. For these extrapolations mathematical models should be used, which require microalgae species specific input parameters. In this thesis input parameters for two industrially relevant microalgae species were obtained and reported. Finally a techno-economic evaluation was developed to indicate the potential of microalgae as a bulk commodity and to pinpoint focal points for future research.

Towards industrial products from microalgae
Ruiz Gonzalez, Jesus ; Olivieri, Guiseppe ; Vree, J.H. de; Bosma, R. ; Willems, Philippe ; Reith, J.H. ; Eppink, M.H.M. ; Kleinegris, D.M.M. ; Wijffels, R.H. ; Barbosa, M.J. - \ 2016
Energy & Environmental Science 9 (2016)10. - ISSN 1754-5692 - p. 3036 - 3043.
Our society needs new sustainable biobased feedstocks to meet population growth and reduce dependence on fossil fuels. Microalgae are considered one of the most promising feedstocks for sustainable production of food, feed, chemicals, materials and fuels. Our mission is to develop a commercial and sustainable production chain for commodity products from microalgae. Estimations of biomass production costs for a 100 ha plant facility have been done. Projections of different scenarios allowed us to compare effect of variables, such as location of the facility, type of cultivation system and operational parameters. As result, this tool shows the most suitable location and system for algae production, as well as the main cost factors. The biomass produced follows to the biorefinery process to be fractionated into the main components: proteins, lipids, carbohydrates and pigments. Several chains have been specifically designed for different market scenarios. The overall turnover coming from the exploitation of the different biomass fractions depends on the end product. A market analysis has been conducted looking to different scenarios according to the biomass value pyramid: biofuels, chemicals, food, feed, specialties in food, cosmetics and a combination of these. Projections show that production of high-value products from microalgae could be profitable nowadays and commodities will become profitable within 10 years.
Turbidostat operation of outdoor pilot-scale photobioreactors
Vree, Jeroen H. de; Bosma, Rouke ; Wieggers, Rick ; Gegic, Snezana ; Janssen, Marcel ; Barbosa, Maria J. ; Wijffels, René H. - \ 2016
Algal Research 18 (2016). - ISSN 2211-9264 - p. 198 - 208.
Areal productivity - Biomass concentration - Microalgae - Nannochloropsis sp. - Outdoor pilot-scale photobioreactors - Photosynthetic efficiency

The effect of biomass concentration on areal productivity and photosynthetic efficiency of Nannochloropsis sp. CCAP211/78 was studied in three outdoor pilot-scale photobioreactors: an open raceway pond (OPR), a horizontal tubular (HT) photobioreactor and a vertically stacked horizontal tubular (VT) photobioreactor. The reactors were operated continuously as turbidostat at different biomass concentrations. For all systems highest areal productivities were obtained on days with a high light intensity, while the highest photosynthetic efficiencies were obtained on days with a low light intensity. Ground areal biomass concentration exceeding 51 g m-2 had a negative effect on the areal productivity and photosynthetic efficiency. No significant effect of biomass concentration on the productivity was found for the HT at ground areal biomass concentration lower than 51 g m-2. Also for the VT, no significant effect of biomass concentration was found with the exception of the highest biomass concentration of 2.0 g L-1 (68 g m-2) resulting in decreased productivity. For the open raceway pond the highest biomass concentration (0.5 g L-1 or 94 g m-2) resulted in significantly lower areal productivity, compared to the lower biomass concentration (0.25 g L 47 g m-2). Highest areal productivities were obtained for OPR and VT, most likely due to more efficient light interception. In this study we observed that night biomass loss was coupled to net growth. At lower biomass concentrations and concomitant higher growth rates the specific biomass loss rate was higher. Microalgal specific light absorption coefficient was correlated to biomass concentration; higher biomass concentrations resulted in higher specific absorption coefficients, resulting in a steeper light gradient in the microalgal cultures.

Outlook on microalgae production chains
Kleinegris, D.M.M. ; Barbosa, M.J. ; Ruiz González, R. ; Bosma, R. ; Vree, J.H. de; Reith, J.H. ; Olivieri, G. ; Eppink, M.H.M. ; Wijffels, R.H. - \ 2015
Comparison of four outdoor pilot-scale photobioreactors
Vree, Jeroen H. De; Bosma, Rouke ; Janssen, Marcel ; Barbosa, Maria J. ; Wijffels, René H. - \ 2015
Biotechnology for Biofuels 8 (2015)1. - ISSN 1754-6834
Areal productivity - Microalgae - Nannochloropsis sp. - Outdoor - Photobioreactors - Photosynthetic efficiency - Pilot-scale

Background: Microalgae are a potential source of sustainable commodities of fuels, chemicals and food and feed additives. The current high production costs, as a result of the low areal productivities, limit the application of microalgae in industry. A first step is determining how the different production system designs relate to each other under identical climate conditions. The productivity and photosynthetic efficiency of Nannochloropsis sp. CCAP 211/78 cultivated in four different outdoor continuously operated pilot-scale photobioreactors under the same climatological conditions were compared. The optimal dilution rate was determined for each photobioreactor by operation of the different photobioreactors at different dilution rates. Results: In vertical photobioreactors, higher areal productivities and photosynthetic efficiencies, 19-24 g m-2 day-1 and 2.4-4.2 %, respectively, were found in comparison to the horizontal systems; 12-15 g m-2 day-1 and 1.5-1.8 %. The higher ground areal productivity in the vertical systems could be explained by light dilution in combination with a higher light capture. In the raceway pond low productivities were obtained, due to the long optical path in this system. Areal productivities in all systems increased with increasing photon flux densities up to a photon flux density of 30 mol m-2 day-1. Photosynthetic efficiencies remained constant in all systems with increasing photon flux densities. The highest photosynthetic efficiencies obtained were; 4.2 % for the vertical tubular photobioreactor, 3.8 % for the flat panel reactor, 1.8 % for the horizontal tubular reactor, and 1.5 % for the open raceway pond. Conclusions: Vertical photobioreactors resulted in higher areal productivities than horizontal photobioreactors because of the lower incident photon flux densities on the reactor surface. The flat panel photobioreactor resulted, among the vertical photobioreactors studied, in the highest average photosynthetic efficiency, areal and volumetric productivities due to the short optical path. Photobioreactor light interception should be further optimized to maximize ground areal productivity and photosynthetic efficiency.

Design and construction of the microalgal pilot facility AlgaePARC
Bosma, R. ; Vree, J.H. de; Slegers, P.M. ; Janssen, M.G.J. ; Wijffels, R.H. ; Barbosa, M.J. - \ 2014
Algal Research 6 (2014)part B. - ISSN 2211-9264 - p. 160 - 169.
tubular photobioreactors - oxygen accumulation - cultivation - principles - systems - growth
Microalgae gained much interest from industry as promising sustainable feedstock for the production of food, feed, bulk chemicals, and biofuels. Pilot scale research on microalgae is needed to bridge the gap between laboratory scale research and commercial applications. The AlgaePARC (Algae Production And Research Center) pilot facility was constructed to bridge this gap. The objective of this pilot center is to compare and improve photobioreactors and operational strategies under outdoor conditions. The pilot plant facility consists of four production systems (raceway pond, horizontal tubular reactor, vertically stacked tubular reactor and flat panels) and allows comparison of performance of these systems under identical climatological conditions. This paper describes the development of this pilot facility, decisions made during the building process and discusses the production systems including technical specifications, measurements and supporting facilities.
Analysis of Fatty Acid Content and Composition in Microalgae
Breuer, G. ; Evers, W.A.C. ; Vree, J.H. de; Kleinegris, D.M.M. ; Martens, D.E. ; Wijffels, R.H. ; Lamers, P.P. - \ 2013
Journal of Visualized Experiments (2013)80. - ISSN 1940-087X - 9 p.
A method to determine the content and composition of total fatty acids present in microalgae is described. Fatty acids are a major constituent of microalgal biomass. These fatty acids can be present in different acyl-lipid classes. Especially the fatty acids present in triacylglycerol (TAG) are of commercial interest, because they can be used for production of transportation fuels, bulk chemicals, nutraceuticals (¿-3 fatty acids), and food commodities. To develop commercial applications, reliable analytical methods for quantification of fatty acid content and composition are needed. Microalgae are single cells surrounded by a rigid cell wall. A fatty acid analysis method should provide sufficient cell disruption to liberate all acyl lipids and the extraction procedure used should be able to extract all acyl lipid classes. With the method presented here all fatty acids present in microalgae can be accurately and reproducibly identified and quantified using small amounts of sample (5 mg) independent of their chain length, degree of unsaturation, or the lipid class they are part of. This method does not provide information about the relative abundance of different lipid classes, but can be extended to separate lipid classes from each other. The method is based on a sequence of mechanical cell disruption, solvent based lipid extraction, transesterification of fatty acids to fatty acid methyl esters (FAMEs), and quantification and identification of FAMEs using gas chromatography (GC-FID). A TAG internal standard (tripentadecanoin) is added prior to the analytical procedure to correct for losses during extraction and incomplete transesterification.
Eindrapportage Hotspot Oude Vaart - Reest
Schaap, B.F. ; Geertsema, W. ; Schotman, H. ; Visser, J.C. ; Vree, L.G. de - \ 2011
Den Haag : Nationaal Onderzoeksprogramma Klimaat voor Ruimte (KvR) - ISBN 9789088150418 - 73
stroomgebieden - beekdalen - watersystemen - scenario-analyse - klimaatfactoren - klimaat - overijssel - drenthe - watersheds - brook valleys - water systems - scenario analysis - climatic factors - climate
De beekdalen in Drenthe zijn bij uitstek gebieden waar de effecten van de klimaatverandering merkbaar zullen zijn. Dat wordt veroorzaakt doordat beeksystemen kwetsbaar zijn voor klimatologische veranderingen. Daarnaast worden de in het gebied aanwezige functies landbouw en natuur in sterke mate beïnvloed door klimaatverandering. Hierbij spelen veranderingen in de waterhuishouding een belangrijke rol.
Pharmacokinetics of enterolignans in healthy men and women consuming a single dose of secoisolariciresinol diglucoside
Kuijsten, A. ; Arts, I.C.W. ; Vree, T.B. ; Hollman, P.C.H. - \ 2005
The Journal of Nutrition 135 (2005)4. - ISSN 0022-3166 - p. 795 - 801.
serum enterolactone concentration - mammalian lignans enterolactone - binding globulin shbg - breast-cancer cells - urinary-excretion - plant lignans - rye bread - metabolism - flaxseed - risk
High concentrations of enterolignans in plasma are associated with a lower risk of acute coronary events. However, little is known about the absorption and excretion of enterolignans. The pharmacokinetic parameters and urinary excretion of enterodiol and enterolactone were evaluated after consumption of their purified plant precursor, secoisolariciresinol diglucoside (SDG). Twelve healthy volunteers ingested a single dose of purified SDG (1.31 ¿mol/kg body wt). Enterolignans appeared in plasma 8-10 h after ingestion of the purified SDG. Enterodiol reached its maximum plasma concentration 14.8 ± 5.1 h (mean ± SD) after ingestion of SDG, whereas enterolactone reached its maximum 19.7 ± 6.2 h after ingestion. The mean elimination half-life of enterodiol (4.4 ± 1.3 h) was shorter than that of enterolactone (12.6 ± 5.6 h). The mean area under the curve of enterolactone (1762 ± 1117 nmol/L·h) was twice as large as that of enterodiol (966 ± 639 nmol/L·h). The mean residence time for enterodiol was 20.6 ± 5.9 h and that for enterolactone was 35.8 ± 10.6 h. Within 3 d, up to 40% of the ingested SDG was excreted as enterolignans via urine, with the majority (58%) as enterolactone. In conclusion, a substantial part of enterolignans becomes available in the blood circulation and is subsequently excreted. The measured mean residence times and elimination half-lives indicate that enterolignans accumulate in plasma when consumed 2-3 times a day and reach steady state. Therefore, plasma enterolignan concentrations are expected to be good biomarkers of dietary lignan exposure and can be used to evaluate the effects of lignans
Concurrentieverhoudingen in de CD-branche
Kemp, R.G.M. ; Mensen, A.H.H.M. ; Pleijster, F. ; Vree, R. de; Zeijden, P.T. van der - \ 2003
Zoetermeer : EIM
Bioavailabilities of quercetin-3-glucoside and quercetin-4'-glucoside do not differ in humans
Olthof, M. ; Hollman, P.C.H. ; Vree, T.B. ; Katan, M.B. - \ 2000
The Journal of Nutrition 130 (2000). - ISSN 0022-3166 - p. 1200 - 1203.
The flavonoid quercetin is an antioxidant which occurs in foods mainly as glycosides. The sugar moiety in quercetin glycosides affects their bioavailability in humans. Quercetin-3-rutinoside is an important form of quercetin in foods, but its bioavailability in humans is only 20␘f that of quercetin-4'-glucoside. Quercetin-3-rutinoside can be transformed into quercetin-3-glucoside by splitting off a rhamnose molecule. We studied whether this 3-glucoside has the same high bioavailability as the quercetin-4'-glucoside. To that end we fed five healthy men and four healthy women (19–57 y) a single dose of 325 ?mol of pure quercetin-3-glucoside and a single dose of 331 ?mol of pure quercetin-4'-glucoside and followed the plasma quercetin concentrations. The bioavailability was the same for both quercetin glucosides. The mean peak plasma concentration of quercetin was 5.0 ± 1.0 ?mol/L (±SE) after subjects had ingested quercetin-3-glucoside and 4.5 ± 0.7 ?mol/L after quercetin-4'-glucoside consumption. Peak concentration was reached 37 ± 12 min after ingestion of quercetin-3-glucoside and 27 ± 5 min after quercetin-4'-glucoside. Half-life of elimination of quercetin from blood was 18.5 ± 0.8 h after ingestion of quercetin-3-glucoside and 17.7 ± 0.9 h after quercetin-4'-glucoside. We conclude that quercetin glucosides are rapidly absorbed in humans, irrespective of the position of the glucose moiety. Conversion of quercetin glycosides into glucosides is a promising strategy to enhance bioavailability of quercetin from foods.
Methodiek voor de evaluatie en optimalisatie van routine waterkwaliteitsmeetnetten. Dl 2. Overzicht van technieken en methoden.
Vree, L. de; Blind, M.W. - \ 1998
Utrecht : Stowa - ISBN 9789057730283
rivieren - waterlopen - kanalen - water - oppervlaktewater - waterverontreiniging - waterkwaliteit - hydrologie - meting - instrumenten (meters) - monitoring - netwerken - geostatistiek - rivers - streams - canals - surface water - water pollution - water quality - hydrology - measurement - instruments - networks - geostatistics
Overview state of the art of cleaning technologies for soils contaminated with HCH.
Rulkens, W.H. ; Vree, H.B.R.J. van; Urlings, L.G.C.M. - \ 1996
In: Proc. 4th Forum on HCH and unwanted pesticides. Poznan. PPI, Poland & TAUW Milieu, The Netherlands (1996) 13 pp
Saneringstechnologie biedt perspektief voor schoonmaken Nederlandse bodem.
Vree, H.B.R.J. van; Pijls, C.G.J.M. ; Cuperus, J.G. ; Urlings, L.G.C.M. ; Grotenhuis, J.T.C. - \ 1993
Proces Technologie 7 (1993). - ISSN 0924-7343 - p. 10 - 15.
Plasma disposition and renal clearance of sulphadimidine and its metabolites in laying hens.
Nouws, J.F.M. ; Geertsma, M.F. ; Grondel, J.L. ; Aerts, M.M.L. ; Vree, T.B. ; Kan, C.A. - \ 1988
Research in Veterinary Science 44 (1988). - ISSN 0034-5288 - p. 202 - 207.
Residues of sulphadimidine and its metabolites in eggs following oral sulphadimidine medication of hens
Geertsma, M.F. ; Nouws, J.F.M. ; Grondel, J.L. ; Aerts, M.M.L. ; Vree, T.B. ; Kan, C.A. - \ 1987
Veterinary Quarterly 9 (1987)1. - ISSN 0165-2176 - p. 67 - 75.
Pharmacokinetics, hydroxylation and acetylation of sulphadimidine in man, ruminants, horses, pigs and fish.
Nouws, J.F.M. ; Vree, T.B. ; Breukink, H.J. ; Miert, A.S.J.P.A.M. van; Grondel, J.L. - \ 1986
In: Comp. Vet. Pharm. Tox. and Ther., van Miert (ed.). 3rd. EAVPT Congr. Ghent, Belgium. MPT Press Ltd., Lancaster - p. 301 - 318.
Pharmacokinetics and residues of sulphadimidine, its N4-acetyl- and hydroxy-metabolites in food producing animals.
Nouws, J.F.M. ; Vree, T.B. ; Aerts, M.M.L. ; Grondel, J.L. - \ 1986
Archiv für Lebensmittelhygiene 37 (1986). - ISSN 0003-925X - p. 57 - 84.
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