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International audience; Bioeconomy addresses the triple balancing challenge posed by the Paris Agreement: inducing additional GHG mitigation alongside biophysical carbon dioxide removals, while keeping fossil carbon in the ground. The use of woody plants as construction materials could simultaneously address this challenge: CO2 is absorbed through photosynthesis, while wood-based products provide mitigation by replacing either petrochemical materials such as plastic boards or energy-intensive materials like bricks. This study combines, at the scale of France, static and dynamic life cycle assessment with soil carbon simulations to investigate the long-term environmental performance of using, as input for the building sector, black locust (Robinia pseudoacacia L.) planted on “carbon vulnerable lands”. These are areas specifically selected for their low soil organic carbon (SOC) levels and low potential to interfere with food security. After the consecutive cultivation of three rotations, black locust was shown to stock an additional 92000 kg ha−1 of carbon in soils as SOC. The mitigation effect from the plastic board replacement is the major contributor to the assessed environmental impacts, including climate change, leading the black locust system to generally perform better than the reference system where the carbon vulnerable areas are left as they are with their initial vegetation. Considering that cultivation starts in 2022, the dynamic evaluation of the global mean temperature change (GMTC) shows that the black locust system results in net negative emissions in the near- and mid-term, but with a GMTC overshot in the second half of the century. Even if a considerable carbon stock is created through time (e.g., 81% and 39% of the carbon captured by photosynthesis, in 2050 and 2100 respectively), the GHG emissions stemming from manufacturing and end-of-life processes were shown to offset the benefit of carbon capture.

The removal of additional carbon dioxide from the atmosphere is indispensable for controlling global warming. This study proposed the concept of ‘biopump’, as plants capable of significantly transferring carbon into the soil. The Carbon Storage in Arable land and Anthropogenic Products (CSAAP) relates to the cultivation of ‘biopumps’ on marginal arable lands poor in soil organic carbon (SOC) and their conversion into long-lived anthropogenic products. Based on a list of twenty-seven biopumps assembled from a literature review, this study proposed a method for the regional prioritization of biopumps, considering among others their ability to increase SOC and adaptation. A list with eight woody and eight herbaceous biopumps was recommended for France. To illustrate the potential of the CSAAP strategy for products encompassing a variety of lifetimes, carbon flows, from biopump cultivation to biomaterial manufacturing and end-of-life, were tracked in time to calculate their influence on global mean temperature change. An illustration was performed on the basis of a French case study, where Miscanthus is grown on spatially identified marginal lands quantified as 11,187- 24,007 km2. Planting biopumps on these lands could increase by 0.23 to 0.49 Mt carbon stocked as SOC annually, which represents 0.19%- 0.41% of the annual French carbon budget during 2015-2018. If the carbon contained in the biomass is indefinitely kept in anthropogenic products, it could represent 13.07% of the same carbon budget. We concluded that biopumps could induce negative emission by 2100, with efficiency strongly depending upon carbon’ residence time in the anthroposphere.

International audience; A framework model is proposed to evaluate the actual overall growth rate of microalgae in an outdoor tubular photobioreactor. A Monte Carlo-based radiative transfer modeling approach describes the local distribution of light energy inside the broth as a function of static (reactor geometry, location) and dynamic solar radiation parameters (angle of incidence, direct and diffuse solar contribution, incident radiation intensity). The light fields are coupled to a Lagrangian discrete random walk tracking of the cells to give the light variations experienced by each microalga for different broth flow rates. The cell light experiments are combined with a dynamic biological model to statistically calculate the actual overall growth rate. Using this model, 380 numerical experiments were performed for a wide range of geographic, light, biomass concentration, and broth flow turbulence conditions. Correlations for a normalized growth rate, Gamma, relating the actual overall growth rate to its asymptotic behaviors (i.e., the instantaneous response and the full integration response), are proposed. The results clearly show that, for a fixed broth flowrate, Gamma does not change with cell concentration variation. Under given light conditions, the level of turbulence linearly manages Gamma, and thus the efficiency of sunlight utilization by the photobioreactor biomass can be tuned by the broth flow rate in the tubular photobioreactor. Gamma also increases linearly with the diffuse fraction of solar radiation. A simple correlation is proposed for fast calculation of the actual overall growth rate.

International audience; The purpose of the research is to make a first step towards rationalizing green polymeric membrane preparation. A holistic methodological approach based on metrics that consider technical, environmental, health and safety issues have been suggested to assess sustainability of membrane preparation. Metrics have been applied to solvent substitution in a non-solvent induced phase separation process. The flammability hazard of three shortlisted alternative solvents has substituted the reprotoxicity hazard of common solvents. The ultrafiltration cellulose diacetate membranes prepared with methyl lactate as solvent have a greater renewable intensity and require a lower number of solvents for their preparation. Trade-offs between use of resources (polymer, solvent, energy…) and membrane properties are inevitable. Further socio-economic, risk and life cycle analysis are crucial to fully integrate ecodesign in membrane preparation.

Climate neutrality is becoming a core long-term competitiveness factor within the aviation industry, as demonstrated by the several innovations and targets set within that sector, prior to and especially after the COVID-19 crisis. Ambitious timelines are set, involving important investment decisions to be taken in a 5-years horizon time. Here, we provide an in-depth review of alternative energy sourcing technologies for aviation revealed to date, which we classified into three main categories, namely liquid fuels (biofuels, electrofuels), electric aviation (all electric and hybrid), and carbon-free options (hydrogen-based, solar-powered). For liquid fuels, 10 pathways were reviewed, for which we supply the detailed process flow picturing all input, output, and co-products generated. The market uptake and use of these co-products were also investigated, along with the overall international regulations and targets for future aviation. As most of the inventoried pathways require hydrogen, we further reviewed six existing and emerging carbon-free hydrogen production technologies. Our review also details the five key battery technologies available (lithium-ion, advanced lithium-ion, solid-state battery, lithium-sulfur, lithium-air) for aviation, as well as the possible configuration schemes for electric propulsion (parallel electric hybrid, series electric hybrid, all electric, partial turboelectric and full turboelectric) and reflects upon the inclusion of hydrogen-powered fuel cells with these configurations. Our review studied these three categories of energy sourcing pathways as modular technologies, yet these still have to be used in a hybridized fashion with conventional fossil-based kerosene. This is among others due to an aromatics content below the standardized requirements for biofuels and electrofuels, to a too low energy storage capacity in the case of batteries, or a sub-optimal gas turbine engine in the case of cryogenic hydrogen. Yet, we found that the latter was the only available option, based on the current and emerging technologies reviewed, for a long-range aviation completely decoupled of fossil carbon. The various challenges and opportunities associated with all these technologies are summarized in this study.

International audience; Over 1.7 billion students around the world have had their education disrupted by the spread of the Coronavirus disease worldwide. Schools and universities have not faced this level of disruption since World War II. The COVID-19 pandemic presented a colossal challenge for teachers to urgently and massively adapt all their classes to distance learning in order to maintain educational continuity with the same quality. Even if some teachers and certain classes were ready to face the situation, a large majority had to adapt their teaching and learning in a very short time without training, with insufficient bandwidth, and with little preparation. This unexpected and rapid transition to online learning has led to a multiplication of teachers' strategies for distance learning in lectures, tutorials, project groups, lab works, and assessments. The purpose of this paper is to present the feedback from students and teachers who participated in the lockdown semester of two different groups of a 5-year program in Chemistry, Environment and Chemical Engineering (100 students) at INSA Toulouse (France). The analysis has highlighted some great successes and some failures in the solutions proposed. Consequently, some guidelines can be given to help us all to learn the lessons of such a singular experience in order to face the unexpected future with more knowledge and more successful distance learning. Teachers have shown very strong resilience during this crisis, at the cost of significant personal commitment. They admit that they have learned more about distance education in two months than in the last 10 years.

International audience; Innovative treatment technologies and management methods are necessary to valorise the constituents of wastewater, in particular nutrients from urine (highly concentrated and can have significant impacts related to artificial fertilizer production). The FP7 project, ValuefromUrine, proposed a new two-step process (called VFU) based on struvite precipitation and microbial electrolysis cell (MEC) to recover ammonia, which is further transformed into ammonium sulphate. The environmental and economic impacts of its prospective implementation in the Netherlands were evaluated based on life cycle assessment (LCA) methodology and operational costs. In order to tackle the lack of stable data from the pilot plant and the complex effects on wastewater treatment plant (WWTP), process simulation was coupled with LCA and costs assessment using the Python programming language. Additionally, particular attention was given to the propagation and analysis of inputs uncertainties. Five scenarios of VFU implementation were compared to the conventional treatment of 1 m(3) of wastewater. Inventory data were obtained from SUMO software for the WWTP operation. LCA was based on Brightway2 software (using ecoinvent database and ReCiPe method). The results, based on 500 iterations sampled from inputs distributions (foreground parameters, ecoinvent background data and market prices), showed a significant advantage of VFU technology, both at a small and decentralized scale and at a large and centralized scale (95% confidence intervals not including zero values). The benefits mainly concern the production of fertilizers, the decreased efforts at the WWTP, the water savings from toilets flushing, as well as the lower infrastructure volumes if the WWTP is redesigned (in case of significant reduction of nutrients load in wastewater). The modelling approach, which could be applied to other case studies, improves the representativeness and the interpretation of results (e.g. complex relationships, global sensitivity analysis) but requires additional efforts (computing and engineering knowledge, longer calculation time). Finally, the sustainability assessment should be refined in the future with the development of the technology at larger scale to update these preliminary conclusions before its commercialization.