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Algal-based bioenergy products have faced multiple economic and environmental problems. To counter these problems, algal-based biorefineries have been proposed as a promising solution. Multiple environmental and economic assessments have analyzed this concept. However, a wide variation in results was reported. This study performs a review to evaluate the methodological reasons behind this variation. Based on this review, four main challenges for a sustainability assessment were identified: 1) the use of a clear framework; 2) the adaptation of the methodology to all stages of technological maturity; 3) the use of harmonized assumptions; 4) the integration of the technological process. A generic methodology, based on the integration of a techno-economic assessment methodology and a streamlined life cycle assessment was proposed. This environmental techno-economic assessment can be performed following an iterative approach during each stage of technology development. In this way, crucial technological parameters can be directly identified and evaluated during the maturation of the technology. The use of this assessment methodology can therefore act as guidance to decrease the time-to-market for innovative and sustainable technologies.

Economic and technological assessments have identified difficulties with the commercialization of bulk products from microalgae, like biofuels. To overcome these problems, a multi-product algal-based biorefinery has been proposed. This paper performs a techno-economic assessment of such a biorefinery. Four production pathways, ranging from a base case with commercial technologies to an improved case with innovative technologies, are analyzed. All region-specific parameters were adapted to Belgian conditions. Three scenarios result in techno-economically viable production plants. The most profitable scenario is the scenario which uses a specialized membrane for medium recycling and an open pond algae cultivation. Although the inclusion of a photobioreactor decreases the culture medium costs, the higher investment costs result in lower economic profits. The carotenoid content and price are identified as critical parameters. Furthermore, the economies of scale assumption for the photobioreactor is critical for the feasibility of this cultivation technology. The techno-economic assessment is an important methodology to guide and evaluate further improvements in research and shorten the time-to-market for innovative technologies in this field.

Apple pomace can be used as resource for the extraction of phenolic compounds with antioxidant properties. Pressing of apple in juice and pomace at lab scale in open air (aerobic) and under N2 atmosphere (anaerobic) showed a recovery of phenolic compounds of 85% in juice and pomace after anaerobic pressing, compared to 43% after aerobic pressing, indicating loss of phenolic compounds by oxidation and the advantage of anaerobic over aerobic pressing. After a membrane screening and concentration test at lab scale, the commercial nanofiltration membrane NFX was selected to concentrate phenolic compounds in an ethanol : water extract of apple pomace. At pilot scale, the concencentration of 10 selected phenolic compounds and quinic acid increased from 59.5 mg/L in the ethanol : water extract to 1256.1 mg/L in the final retentate, that is, by a factor 21.1. The volume of the crude extract was reduced by a factor of 28.5 during the filtration, indicating some loss of phenolic compounds during pilot testing due to membrane fouling or oxidation of polyphenols. The pilot concentration test using a spiral-wound membrane module showed good flux and concentration of phenolic compounds, indicating the technical feasibility of membrane technology for efficient concentration of polyphenols in an ethanol : water extraction solvent. Unfortunately, the extraction and concentration process was not economically feasible under the assumptions made. Practical applications The valorization of food waste for the production of high-added value products is an increasingly hot topic. Phytochemicals are present in relatively low concentration in the fruit matrix, and concentration in the extraction solvent is necessary to develop an industrially relevant process. In this study, membrane filtration was selected for concentration due to its low energy consumption and mild processing conditions compared to other technologies. Membrane screening and testing at lab and pilot scale with techno-economic assessment can be used by food and nutraceutical industries to evaluate membrane technology for concentration of phytochemicals extracted from agroindustrial by-products. Seventh Framework Programme, projectRESFOOD (Resource Efficient and SafeFood Production and Processing), Grant/Award Number: 308316

Since 2016, hobby metal-detecting is legal in Flanders (Belgium), although it was unofficially tolerated for many years before. However, research on metal-detected artefacts in Flanders is hindered by a low reporting rate. The MEDEA project aims to address this by encouraging detectorists to record their finds on an online platform. Finds experts are invited to enrich records with further information and thus instigate a rewarding feedback cycle. This paper discusses MEDEA’s ‘Human-Centred Design’ development process and the design choices underpinning the platform. MEDEA may be seen as an example of ‘Open Archaeology’ and related trends in digital humanities., SCOPUS: ar.j, info:eu-repo/semantics/published

Micro algae are a single celled biomass with a very high potential in the biobased economy. In algal biomass cultivation, the harvesting step (i.e., separation of the dilute single cell algae from the growth medium) is a considerable part of the capital and operational cost. These processes typically require the use of high amounts of chemicals and/or a significant energy input. A second important point of attention in algae cultivation is water recycle. Due to the low concentration of the algae in the cultivation (ca. 0,2 g/l dry algae in open ponds and 2 g/l in photobioreactors), large amounts of water need to be processed to produce algae paste. For example in open pond cultivation a production installation of 1000 ton dry algae per year requires about 700 m³/h water to be processed. Thus for large scale installation medium recycle is a sine qua non. A solution that tackles both issues simultaneously is the submerged flat panel membrane system. The membrane system is used as the first dewatering step in a hybrid system of algae harvesting with centrifugation as final concentration. This technology has the potential to lower energy and investment costs compared to centrifugation alone. The technology furthermore has major advantages on water recycling as > 95 % of the water needs to be removed to produce a 20 % paste of algae. As the membranes don't add any chemicals and remove all suspended solids and bacteria, the technology is very promising toward medium recycle. Submerged membrane filtration is preferred over other membrane filtration technologies (e.g. crossflow filtration), due to its low energy demand and low shearing forces. Membrane fouling is controlled by the cleaning effect of coarse bubbling aeration. Additionally, the flat panel membranes used in this study are backwashable (patented flat sheet membrane envelopes with an integrated permeate channel, IPC). The algae filtration experiments were performed on both lab and pilot-scale submerged reactors with different membranes (MF and UF), algae species (Nannochloropsis, Pavlova, Isochrysis, Phaeodactylum), algae concentration, filtration regimes and filtration cycle times and aeration flows. The results show that membrane operation with backwashing results in higher stable fluxes than operation with only relaxation which is the normal operating mode for submerged membranes. Moreover the flux of UF membranes is more stable than MF membranes and that shorter filtration times result in higher stable fluxes (in the backwashing regime). Aeration flow turned out to be critical towards achievable flux levels and the characteristics of the algae suspension. VITO will further develop and optimize the technology for harvesting and water recycle on pilot scale and demonstration scale. The latest information on the developments of this technology will be presented.

The feasibility of algae harvesting with submerged flat panel membranes was investigated as pre-concentration step prior to centrifugation. Polishing of the supernatant coming from the centrifuge was evaluated as well. The effect of membrane polymer (polyvinyl chloride [PVC], polyethersulfone polyvinyl-pyrollidone [PES-PVP], poly vinylidene fluoride [PVDF] ), pore size (microfiltration [MF], ultrafiltration [UF]), algae cell concentrations and species were investigated at labscale. In addition, backwashing as fouling control was compared to standard relaxation. PVDF was the superior polymer, and UF showed better fouling resistance. Backwashing outperformed relaxation in fouling control. The backwashable membranes allowed up to 300 % higher fluxes compared to commercial flat panelbenchmark (PVC) membranes. Estimations on energy consumption for membrane filtration followed by centrifugation revealed relatively low values of 0.169 kWh/kg of dry weight of algae compared to 0.5 kWh/kg for algae harvesting via classical centrifuge alone. ispartof: Bioresource Technology vol:129 pages:582-591 ispartof: location:England status: published