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The production of hydrogen from biomass by fermentation is one of the routes that can contribute to a future sustainable hydrogen economy. Lignocellulosic biomass is an attractive feedstock because of its abundance, low production costs and high polysaccharide content.Batch cultures of Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana produced hydrogen, carbon dioxide and acetic acid as the main products from soluble saccharides in Miscanthus hydrolysate. The presence of fermentation inhibitors, such as furfural and 5-hydroxylmethyl furfural, in this lignocellulosic hydrolysate was avoided by the mild alkaline-pretreatment conditions at a low temperature of 75 degrees C. Both microorganisms simultaneously and completely utilized all pentoses, hexoses and oligomeric saccharides up to a total concentration of 17 g l-1 in pH-controlled batch cultures. T. neapolitana showed a preference for glucose over xylose, which are the main sugars in the hydrolysate. Hydrogen yields of 2.9 to 3.4 mol H2 per mol of hexose, corresponding to 74 to 85% of the theoretical yield, were obtained in these batch fermentations. The yields were higher with cultures of C. saccharolyticus compared to T. neapolitana. In contrast, the rate of substrate consumption and hydrogen production was higher with T. neapolitana. At substrate concentrations exceeding 30 g l-1, sugar consumption was incomplete, and lower hydrogen yields of 2.0 to 2.4 mol per mol of consumed hexose were obtained.Efficient hydrogen production in combination with simultaneous and complete utilization of all saccharides has been obtained during the growth of thermophilic bacteria on hydrolysate of the lignocellulosic feedstock Miscanthus. The use of thermophilic bacteria will therefore significantly contribute to the energy efficiency of a bioprocess for hydrogen production from biomass.

A multistage reverse electrodialysis system was studied at the REDstack research facility (the Afsluitdijk, the Netherlands) for over 30 days to describe the performance of such configuration under natural water conditions. The experiments were done with two 0.22 × 0.22 m2 stacks in series comprising 32 cell pairs (3.1 m2 of membrane area) for stage 1 and 64 cell pairs (6.2 m2 membrane area) for stage 2. The total gross power density at the available salinity gradient was stable at around 0.35 W•m􀀀 2. The total net power density, corrected for the initial pressure drop of the stacks, was 0.25 W•m􀀀 2 at an energy efficiency of 37 %. Throughout the operation, due to increased stack pressure drop, the actual total net power density lowered to 0.1 W•m􀀀 2. A distinct behaviour was found for multivalent ions in each stage. For stage 1, Ca2+ and SO42􀀀 were transported from the river water to the seawater side, so-called uphill transport. For stage 2, uphill transport was not found, in line with Donnan potential calculations. Stack autopsy revealed microorganisms with sizes ten times larger than the cartridge filter nominal pore size (5 μm) and biofilm covering part of the spacer open area, both contributing to the increasing pressure drop in the stacks. This study showed that stable gross power densities and high energy efficiencies were obtained from feeding natural waters to a multistage reverse electrodialysis system, independent of fouling. In addition, it emphasized the importance of maintaining pumping power losses low for a viable deployment of the technology.

AbstractAnalyzing the politics and policy implications in Brazil of attributing extreme weather events to climate change, we argue for greater place-based sensitivity in recommendations for how to frame extreme weather events relative to climate change. Identifying geographical limits of current recommendations to emphasize the climate role in such events, we explore Brazilian framings of the two tragic national disasters, as apparent in newspaper coverage of climate change. We find that a variety of contextual factors compel environmental leaders and scientists in Brazil to avoid and discourage highlighting the role of climate change in national extreme events. Against analysts’ general deficit-finding assumptions, we argue that the Brazilian framing tendency reflects sound strategic, socio-environmental reasoning, and discuss circumstances in which attributing such events to climate change—and, by extension, attribution science—can be ineffective for policy action on climate change and other socio-environmental issues in need of public pressure and preventive action. The case study has implications beyond Brazil by begging greater attention to policies and politics in particular places before assuming that attribution science and discursive emphasis on the climate role in extreme events are the most strategic means of achieving climate mitigation and disaster preparedness. Factors at play in Brazil might also structure extreme events attribution politics in other countries, not least some other countries of the global South.

Duurzame landbouw in beeld 2007 geeft de resultaten weer van de Nederlandse land- en tuinbouw op alle relevante duurzaamheidsaspecten. Zowel de meest recente cijfers als de langetermijnontwikkelingen worden gepresenteerd. Naast de resultaten voor de sector als geheel worden de bedrijfstypen glastuinbouw, melkveehouderij en varkenshouderij afzonderlijk behandeld. A view of sustainable agriculture in 2007 presents the results of Dutch agriculture and horticulture for all relevant sustainability aspects, including the most recent figures and long term developments. Besides the results for the sector as a whole, it looks at the different types of enterprise, i.e. greenhouse horticulture, dairy farms and pig farms, separately.

The work described for this deliverable was carried out by DLO-PRI, in collaboration with WU, and aim ed to understanding lipid production in Phaeodactylum tricornutum . By means of transcriptome, proteome and metabolome analyses we aimed to provide insight into the one step lipid production performed by partner WU. Cultivation conditions were chosen to steer lipid profile towards most suitable composition for biofuel production.

Het onderzoek is opgesplitst in 3 deelonderzoeken. Het 1e richtte zich op de verbetering van het vergistingsrendement via een betere besturing en beheersing van het proces en een efficientere omzetting van biogas in elektriciteit en warmte. Het 2e betrof het zuiveren van biogas. Er werden gegevens verzameld over drogen van biogas en t.a.v. 3 zuiveringsmethoden die mogelijkheden bieden voor toepassing op de boerderij: droge gaszuivering met ijzeroxide, gaswassing met ijzerhoudend grondwater en toediening van ijzerchloride aan de mest. Het 3e deelonderzoek betrof het meten van de energiestromen op 2 melkveebedrijven, 2 gesloten varkensbedrijven en 2 leghennenbedrijven om het verbruikspatroon vast te leggen en te analyseren

Op een varkensbedrijf wordt het directe energieverbruik vooral bepaald door de energiebehoefte voor ventilatie en verwarming. Ventilatie in varkensstallen dient enerzijds voor de afvoer van stoffen die in de stal aan de lucht worden afgegeven (bijvoorbeeld CO2, NH3, geur) en anderzijds voor de afvoer van overtollige warmte.