Ocean Remote sensing, data, IMT Atlantique

Ocean remote sensing: solving the puzzle of missing data

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The satellite measurements that are taken every day rely greatly on atmospheric conditions, the main cause of missing data. In a scientific publication, Ronan Fablet, a researcher at Télécom Bretagne, proposes a new method for reconstructing the temperature of the ocean surface to complete incomplete observations. This reconstructed data provides fine-scale mapping of the homogeneous details that are essential in understanding the many different physical and biological phenomena.

 

What do a fish’s migration through the ocean, a cyclone, and the Gulf Stream have in common? They can all be studied using satellite observations. This is a theme Ronan Fablet appreciates. As a researcher at Télécom Bretagne, he is particularly interested in processing satellite data to characterize the dynamics of the ocean. This designation involves several themes, including the reconstruction of incomplete observations. Missing data impairs satellite observations and limits the representation of the ocean, its activities and interactions. This represents essential components used in various areas, from the study of marine biology to ocean-atmosphere exchanges that directly influence the climate. In an article published in June 2016 in the IEEE J-STARS[1] Ronan Fablet proposed a new statistical interpolation approach for compensating for the lack of observations. Let’s take a closer look at the data assimilation challenges in oceanography.

 

Temperature, salinity…: the oceans’ critical parameters

In oceanography, the name of a geophysical field refers to its fundamental parameters of sea surface temperature (or SST), salinity (quantity of salt dissolved in the water), water color, which provides information on the primary production (chlorophyll concentrations), and the altimetric mapping (ocean surface topography).

Ronan Fablet’s article focuses on the SST for several reasons. First of all, the SST is the parameter that is measured the most in oceanography. It benefits from high-precision or high-resolution measurements. In other words, a relatively short distance of one kilometer separates two observed points, unlike salinity measurements, which have a lower level of precision (distance of 100km between two measurement points). Surface temperature is also an input parameter that is often used to design digital models for studying ocean-atmosphere interactions. Many heat transfers take place between the two. One obvious example is cyclones. Cyclones are fed by pumping heat from the oceans’ warmer regions. Furthermore, the temperature is also essential in determining the major ocean structures. It allows surface currents to be mapped on a small-scale.

But how can a satellite measure the sea surface temperature? As a material, the ocean will react differently to a given wavelength. “To study the SST, we can, for example, use an infrared sensor that first measures the energy. A law can then be used to convert this into the temperature,” explains Ronan Fablet.

 

Overcoming the problem of missing data in remote sensing

Unlike the geostationary satellites that orbit at the same speed as the Earth’s rotation, moving satellites generally complete one orbit in a little over 1 hour and 30 minutes. This enables them to fly over several terrestrial points in one day. They therefore build images by accumulating data. Yet some points in the ocean cannot be seen. The main cause of missing data is satellite sensors’ sensitivity to atmospheric conditions. In the case of infrared measurements, clouds block the observations. “In a predefined area, it is sometimes necessary to accumulate two weeks’ worth of observations in order to benefit from enough information to begin reconstructing the given field,” explains Ronan Fablet. In addition, the heterogeneous nature of the cloud cover must be taken into account. “The rate of missing data in certain areas can be as high a 90%,” he explains.

The lack of data is a true challenge. The modelers must find a compromise between the generic nature of the interpolation model and the complexity of its calculations. The problem is that the equations that characterize the movement of fluids, such as water, are not easy to process. This is why these models are often simplified.

 

A new interpolation approach

According to Ronan Fablet, the techniques that are being used do not take full advantage of the available information. The approach he proposes reaches beyond these limits: “we currently have access to 20 to 30 years of SST data. The idea is that among these samples we can find an implicit representation of the ocean variations that can identify an interpolation. Based on this knowledge, we should be able to reconstruct the incomplete observations that currently exist.”

The general idea of Ron Fablet’s method is based on the principle of learning. If a situation that is observed today corresponds to a previous situation, it is then possible to use the past observations to reconstruct the current data. It is an approach based on analogy.

 

Implementing the model

In his article, Ronan Fablet therefore used an analogy-based model. He characterized the SST based on a law that provides the best representation of its spatial variations. The law that was chosen provides the closest reflection of reality.

In his study, Ronan Fablet used low-resolution SST observations (100km distances between two observations). With low-resolution data, optimum interpolation is usually favored. The goal is to reduce errors in reconstruction (differences between the simulated field and observed field) at the expense of small-scale details. The image obtained through this process has a smooth appearance. However, when the time came for interpolation, the researcher chose to maintain a high level of detail. The only uncertainty that remains is where the given detail is located on the map. This is why he opted for a stochastic interpolation. This method can be used to simulate several examples that will place the detail in different locations. Ultimately, this approach enabled him to create SST fields with the same level of detail throughout, but with the local constraint of the reconstruction error not improving on that of the optimum method.

“The proportion of ocean energy within distances under 100km is very significant in the overall balance. At these scales, a lot of interaction takes place between physics and biology. For example, schools of fish and plankton structures are formed under the 100km scale. Maintaining a small-scale level of detail also serves to measure the impact of physics on ecological processes,” explains Ronan Fablet.

 

The blue circle represents the missing data fields. The maps represent the variations in SST at low-resolution based on a model (left), and at high-resolution based on observations (center) and at high resolution based on the model in the article (right).

 

New methods ahead using deep learning

Another modeling method has recently begun to emerge using deep learning techniques. The model designed using this method learns from photographs of the ocean. According to Ronan Fablet, this method is significant: “it incorporates the idea of analogy, in other words, it uses past data to find situations that are similar to the current context. The advantage lies in the ability to create a model based on many parameters that are calibrated by large learning data sets. It would be particularly helpful in reconstructing the missing high-resolution data from geophysical fields observed using remote sensing.”

 

Also read on I’MTech

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Remote sensing explained: from agriculture to major disasters

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Sea Tech Week: Key issues of a connected ocean

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[1] Journal of Selected Topics in Applied Earth Observations and Remote Sensing. An IEEE peer-reviewed journal.

Pollutants, Département SAGE, Mines Douai, Frédéric Thévenet, COV

Removing pollutants from our homes

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Indoor air is polluted with several volatile organic compounds, some of which are carcinogenic. Frédéric Thévenet, a researcher at Mines Douai, develops solutions for trapping and eliminating these pollutants, and for improving tests for air purifying devices.

 

We spend nearly 90% of our time inside: at home, at the office, at school, or in our car. Yet the air is not as clean as we think – it contains a category of substances called volatile organic compounds (VOCs), some of which are harmful. Fighting these VOCs is Frédéric Thévenet’s mission. Frédéric is a researcher with the Department of Atmospheric Sciences and Environmental Engineering (SAGE) at Mines Douai, a lab specialized in analytical chemistry capable of analyzing trace molecules.

 

Proven carcinogens

VOCs are gaseous organic molecules emitted in indoor environments from construction materials, paint and glue on furniture, cleaning and hygiene products, and even from cooking. One specific molecule is a particular cause for concern: formaldehyde, both a proven carcinogen and the compound with the highest concentration levels. Guideline values exist (concentration levels that must not be exceeded) for formaldehyde, but they are not yet mandatory.

The first way to reduce VOCs is through commonsense measures: limit sources by choosing materials and furniture with low emissions, choose cleaning products carefully and, above all, ventilate frequently with outdoor air. But sometimes this is not enough. This is where Frédéric Thévenet comes into play: he develops solutions for eliminating these VOCs.

 

Trap and destroy

There are two methods for reducing VOCs in the air. They can be trapped on a surface through adsorption (the molecules bind irreversibly to the surface), and the traps are then replenished. The compounds can also be trapped and destroyed immediately, generally through oxidation, by using light (photocatalysis). “But in this case, you must make sure the VOCs have been completely destroyed; they decompose into water and CO2, which are harmless,” the researcher explains. “Sometimes the VOCs are only partially destroyed, thus generating by-products that are also dangerous.”

 

Polluants, Frédéric Thévenet, Mines Douai, Département SAGE

 

At the SAGE Department, Frédéric works in complementary fashion with his colleagues from the VOC metrology team. They take their measurement devices to the field. He prefers to reproduce the reality of the field in the laboratory: he created an experimental room measuring 40 cubic meters, called IRINA (Innovative Room for INdoor Air studies), where he recreates different types of atmospheres and tests procedures for capturing and destroying VOCs. These procedures are at varying stages of development: Frédéric tests technology already available on the market that the ADEME (The French Environment and Energy Management Agency) wants to evaluate, as well as adsorbent materials developed by manufacturers who are looking to improve the composition. He also works on even earlier stages, developing his own solutions in the laboratory. “For example, we test the regeneration of adsorbents using different techniques, particularly with plasma,” he explains.

 

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A long-overdue law

Only laws and standards will force manufacturers to develop effective solutions for eliminating volatile organic compounds. Yet current legislation is not up to par. Decree no. 2011-1727 of 2 December 2011 on guideline values for formaldehyde and benzene in indoor air provides that the concentration levels of these two VOCs must not exceed certain limits in establishments open to the public: 30 µg/m³ for formaldehyde and 5 µg/m³ for benzene, for long-term exposure. However, this law has not yet come into force, since the decrees implementing this measure have not yet been issued. The number of locations affected by this law make it very difficult to implement. The law’s implementation has been postponed until 2018, and even this date remains uncertain.

Furthermore, the Decree of 19 April 2011 on labelling volatile pollutant emissions for construction products, wall cladding, floor coverings, and paint and varnishes is aimed at better informing consumers on VOC emissions from construction materials, paint and varnishes. These products must include a label indicating the emission levels for 11 substances, on a four-category scale ranging from A+ to C, based on the energy label model for household appliances.[/box]

 

Improving the standards

What are the results? For now, the most interesting results are related to adsorbent construction materials, for example, when they are designed to become VOC traps. “They don’t consume energy, and show good results in terms of long-term trapping, despite variations due to seasonal conditions (temperature and humidity),” explains Frédéric. “When these materials are well designed, they do not release the emissions they trap.” All these materials are tested in realistic conditions, by verifying how these partitions perform when they are painted, for example.

As well as testing the materials themselves, the research is also aimed at improving the standards governing anti-VOC measures, which seek to come as close as possible to real operating conditions. “We were able to create a list of precise recommendations for qualifying the treatments,” the researcher adds. The goal was to obtain standards that truly prove the devices’ effectiveness. Yet today, this is far from the case. An investigation published in the magazine Que Choisir in May 2013 showed that most of the air purifiers sold in stores were ineffective, or even negatively affected the air quality by producing secondary pollutants. There was therefore an urgent need to establish a more scientific approach in this area.

 

Polluants, Frédéric Thévenet, MInes Douai

A passion for research

For some, becoming a researcher is the fulfilment of a childhood dream. Others are led to the profession through chance and the people they happen to meet. Frédéric Thévenet did not initially see himself as a researcher. His traditional career path, taking preparatory classes for an engineering school (Polytech’ Lyon), was initially leading him towards a future in engineering. Yet a chance meeting caused him to change his mind. During his second year at Polytech’, he did an internship at a research lab under the supervision of Dominique Vouagner, a researcher who was passionate about her work at the Institut Lumière Matière (ILM), a joint research unit affiliated with the Claude Bernard University Lyon 1 and CNRS. “I thought it was wonderful, the drive to search, to question, the experimental aspect… It inspired me to earn my DEA (now a Master 2) and apply for a thesis grant.” He was awarded a grant from ADEME on the subject of air treatment… although his studies had focused on material sciences. Still, it was a logical choice, since materials play a key role in capturing pollutants. Frédéric does not regret this choice: “Research is a very inspiring activity, involving certain constraints, but also much room for freedom and creativity.”

Bioplastics, Mines Douai

Bioplastics: “still a long road to higher performance”

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As required by environmental transition, materials of the future must be “greener”. Bioplastics in particular have become a main focus of attention, and are often presented as the solution to the pollution caused by the plastics we use every day, which can take hundreds of years to decompose. Patricia Krawczak, a researcher at Mines Douai, studies these new polymers. Yet she issues this warning: our expectations must remain reasonable, because it will take time for bioplastics to become efficient and profitable… and not all of them are biodegradable.

 

Plastic materials are inextricably linked to our everyday lives. They are essential, and yet are often seen as a scourge of modern times. Their negative impact on the environment is often denounced, such as the millions of tons[1] of polymer waste disposed of in the oceans each year, negatively impacting marine biodiversity. Not to mention that producing these plastics requires hydrocarbons, and hence the use of fossil fuels. The scientific community is seeking to offer alternative solutions in response to this situation: “agro-based” or “bio-sourced” plastics made from natural materials of plant or animal origin, also referred to as bioplastics. At Mines Douai, this new “green” form of plastics processing is one of the key research areas of the TPCIM department directed by Patricia Krawczak.

“The current challenge is to develop bio-sourced polymers with higher added value, to set them apart from the widely-distributed plastics, called commodity plastics — such as polyolefins. The goal is to compete against technical plastics, or performance plastics, from the traditional, petrochemical derived process — such as polyamides and polycarbonates,” the materials researcher explains. These major polymer families Patricia Krawczak mentions are often used in key sectors, such as transportation (automotive, aeronautics, etc.), which are large-scale consumers of plastics. Yet entering these markets proves to be a difficult task, due to the demanding specifications.

Herein lies one of bioplastics’ greatest challenges: proving, if not their superiority, at least their equal performance compared to conventional polymers under strict operating conditions. Yet this is far from always the case. “For the time being, industrial-scale bio-sourced products are primarily used for applications in the low value-added packaging sector, such as  bags for supermarkets,” the scientist explains. The properties of the majority of these bioplastics are not yet adapted for producing vehicle components, such as under-the-hood automotive parts, which must be resistant to high temperatures and constant or repeated mechanical stress over time.

This is why much work remains to be done before certain attractive properties can be achieved, and explains the need to temper the excitement about bioplastics. Patricia Krawczak is very clear on this point: “We cannot yet compete with one hundred years of research in the field of petrochemical plastics processing. The road to high performance is still long for bio-sourced plastics.”

The “conventional” plastics industry has indeed been successful in developing a wide range of materials, able to meet the thermo-mechanical and physico-chemical demands of specific uses, and comply with strict application specifications. The range is much larger than what the few bioplastics currently being produced can offer. Not to mention the fact that these bioplastics sometimes have unattractive psychosensorial properties (smells, colors, transparency). A cloudy or yellowish appearance can make certain applications unacceptable, such as for food packaging or touchscreens; and the foul-smelling compounds generated during processing or during use can be disturbing.

However, this does not mean that bioplastics will be forever confined to markets for low value-added products. But hopes of quickly replacing all plastics from petroleum fractions with bioplastics should be tempered for the time being. However, a few examples do exist of bioplastics offering very good properties or even new functions, and are winning over plastics processing industrials and purchasers. This is the case for a bio-sourced polymer developed by Mitsubishi and marketed under the name of Durabio. Its impact resistance is comparable to that of conventional polycarbonate, as well having a high degree of transparency and excellent optical properties (resistance to UV yellowing) and surface properties (hardness, scratch and abrasion-resistance) that surpass its petroleum-based counterparts, and justify its price.

 

Bioplastics need to keep up with the pace!

One of the major hurdles to overcome — in addition to having the characteristics required to comply with application specifications — is that of the potential additional cost of using bioplastics. Bio-sourced polymers’ access to downstream markets is in fact subject to an inescapable condition: to remain competitive, manufacturers of plastic parts cannot consider investing in new production methods or substantially modifying their existing machinery. “It is therefore crucial to ensure that bioplastics can be integrated into current production lines, with technical performances, and production costs and speed that are compatible with market constraints,” Patricia Krawczak points out. Yet, this is not an easy task. Why? Because certain bio-sourced polymers are sensitive to thermal or thermomechanical degradation during the forming stages for manufactured products.

 

Mines Douai, Patricia Krawczak, Bioplastics

To bring bioplastics to maturity, researchers must make them compatible with current processes.

 

It is therefore up to bioplastics to adapt to the plastics processing procedures used to manufacture industrial parts, not the other way around. For the scientists, this means modifying the plastics’ behavior in liquid form, specifically by adding chemical additives. “A common example is starch, which cannot be processed in its raw state using conventional extrusion methods. It must be plasticized by adding water or polyols, with the aim of lowering the temperature at which it becomes liquid,” the researcher explains. Another approach being explored is mixing bio-sourced polymers to obtain a blend tailored to the specific characteristics required.

Once the appropriate formula has been developed, the work is not yet over. The possible migration of the various additives, or the potential changes to the morphology of the blends during the processing stage must also be controlled, to ensure optimal functional properties. In short, developing bioplastics requires a great deal of optimization.

 

Bio-sourced does not necessarily mean biodegradable

Once the bioplastics are perfectly adapted to current plastic processing procedures, and have become efficient and competitive, it is important to keep the initial goal in mind: reducing the environmental impact. However, green plastics processing is all too often wrongly associated with developing and processing biodegradable plastics. Patricia Krawczak reminds us that green polymers do not necessarily have this feature: “On the contrary, many applications in transportation (cars, airplanes) and construction require durable materials that can be used in the long-term without any form of deterioration.”

Since not all bioplastics are biodegradable, they must be recovered and recycled. And there is no guarantee we will be able to put them in our recycling bins at home. In France, these recycling bins currently only accept a limited number of specific plastics: polyethylene terephthalate, polyethylene and polypropylene. It may not be possible to recycle the new biopolymers using the same facilities. Studies must now be carried out to determine whether or not these biopolymers can be integrated into existing recycling facilities without any disruption, or to determine if new facilities will need to be created.

The problem is, the proportion of biopolymers in the total volume of the plastics produced and consumed in the global market represents only 0.5% of all different types (and an estimated 2% by 2020). “Establishing a recycling program generally requires the generation of a sufficient volume of waste to enable a sustainable economy to be built on the collection, sorting and reutilization procedures. At present, however, the amount of bioplastic waste is too small, and is too diverse,” Patricia Krawczak warns. However, initiatives are being developed to recycle small volumes of waste. This is one of the subjects being discussed by the Circular Economy & Innovation Chair (ECOCIRNOV) led by Mines Douai.

 

A promising future for green plastics?

Research aimed at removing the remaining obstacles is advancing, and the future looks promising for green plastics processing, as it is driven by application sectors with strong potential. In addition to transportation, the biomedical field is interested in biocompatible materials for creating controlled release systems for active ingredients. Patricia Krawczak’s team has worked on this subject in conjunction with a French research group on biomaterials from Nord Pas-de-Calais (Fédération Biomatériaux et Dispositifs Médicaux Fonctionnalisés du Nord Pas-de-Calais). The development of electroactive bio-sourced polymers suitable for 3D printing – the focus of research led by Jérémie Soulestin in one of Patricia Krawczak’s research groups – could also benefit the market for connected objects.

Finally, it is important to remember that polymers, along with fibers, constitute one of the two essential components required for producing composite materials. Chung-Hae Park, also a member of Patricia Krawczak’s team, is already working on the development of flax-based composites. He recently completed the proof of concept for the high-speed manufacturing of parts, with a cycle time of two minutes, close to automotive speeds (one part per minute). Success in offering biopolymers with suitable properties, reinforced with plant fibers, could therefore constitute another step towards developing completely bio-sourced structural composites. This class of materials could potentially have numerous high-performance applications.

 

[1] The United Nations Environment Program published a report in 2016 indicating that between 4.8 and 12.7 million tonnes of plastic were dumped in the world’s seas.

Sea Tech Week, René Garello, Océan connecté

Sea Tech Week: Key issues of a connected ocean

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The sea is becoming increasingly connected, with the development of new real-time transmission sensors. The aggregated data is being used to improve our understanding of the role oceans play in climate issues, but several challenges must be considered: the development of autonomous sensors and the pooling of research on a global level. This was the subject of Sea Tech Week, which took place in Brest from October 10 to 14, bringing together international experts from different disciplines relating to the sea.

 

From renewable marine energies and natural resources to tourism… The sea has many uses – we swim in it, travel on it and exploit all it has to offer. By 2030, the ocean economy (or blue economy) is expected to create great wealth and many jobs. In the meantime, before we reach that distant point in the future, Télécom Bretagne is combining expertise in oceanography with information and communication technology in order to further research in this field.

A global topic

Although the subject was left out of climate conferences up until 2015, the ocean is constantly interacting with the environments around it. It is at the very heart of the subject of climate change. In fact, it is currently the largest carbon sink in existence, leading to acidification, with irreparable consequences for marine fauna and flora.

In this current context, there is an increasing need for measurements. The aim is to obtain an overview of the ocean’s effects on the environment and vice versa. All different types of parameters must be studied to obtain this global view: surface temperatures, salinity, pressure, biological and chemical variables, and the influence of human activities, such as maritime traffic. René Garello,  a researcher at Télécom Bretagne, in a presentation delivered on the first morning of Sea Tech Week, explained the challenges involved in integrating all this new data.

A connected ocean for shared research

The study of the marine world is not immune to recent trends: it must be connected. The goal is to use technological resources to allow large volumes of data to be transmitted by developing coding. This involves adapting aspects of connected object technology to the marine environment.

One challenge involved in the connected ocean field is the development of sophisticated and more efficient sensors to improve in-situ observation techniques. René Garello refers to them as smart sensors. Whether they are used to examine surface currents, or acoustic phenomena, these sensors must be able to transmit data quickly, be autonomous, and communicate with each other.

However, communication is necessary for more than just the sensors. Scientific communities also have their part to play. “On the one hand, we make measurements, and on the other we make models. The question is whether or not what is carried out in a given context is pooled with other measurements carried out elsewhere, allowing it to be integrated to serve the same purpose,” explains René Garello.

Another challenge is therefore to prevent the fragmentation of research which would benefit from being correlated. The goal is to pool both data and stakeholders by bringing together chemical oceanographers and physical oceanographers, modelers and experimenters, with the ultimate aim of better orchestrating global research.

A parallel concern: Big Data

“Currently, only 2% of data is used. We are forced to subsample the data, which means we are less efficient,” observes René Garello. The need to collect as much material as possible is counterbalanced by the human capacity to analyze the material in its entirety. In addition, the data must be stored and processed in different ways. According to René Garello, future research must be carried out in a restrained manner: “Big Data leads to a paradox, because the goal of the research is to decrease data size so users receive a maximum amount of information in minimum amount of space.” Smart sensors can allow a balance to be struck between data compression and Big Data by using an input filtering process, and by not collecting all data, so that work can be carried out on a human scale.

Towards standardization procedures

Not many standards currently exist in the marine sphere,. The question of data integrity and how it represents reality is the last major issue. Satellite sensors are already properly codified, since their measurements are carried out in an environment in which the measurement conditions are stable, unlike in-situ sensors, which can be dragged away by drifting objects and buoys. In this context of mobile resources, the sample must be proven reliable through the prior calibration of the measurement. Research can help to improve this concept of standards.

However, basic research alone is not sufficient. The future also requires links to be forged between science, technology and industry. In a report published in April 2016, the OECD foresees the creation of many ocean-related industries (transport, fishing, marine biotechnology, etc.). How will current research help this blue economy to take shape? From the local context in Brest, to European research programs such as AtlantOS, these issues clearly exist within the same context: everything is interconnected.

 

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Sea Tech Week 2016

Sea Tech Week : A week dedicated to marine sciences and technology

Every two years in Brest, workshops and trade shows are organized in relation to sea-related disciplines. The week is organized by the Brest metropolitan area with support from several research and corporate partners. In 2014, over 1,000 participants arrived in Brittany for this event, 40% of whom were international visitors. In 2016, the event focused on digital technology, in connection with the French Tech label, and addressed the following topics: observation, robotics, modeling, sensors… via 18 conferences led by experts from around the world. Find out more  [/box]

Biomass

Biomass: green gold at our fingertips

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In the race towards renewable resources, biomass could well have an important role to play. Biomass includes organic matter derived from living organisms, particularly plants, which have more to offer than you might think. Patrick Navard is a researcher in materials at Mines ParisTech. Following his presentation at the “Materials: realities and new frontiers” symposium, organized on March 30-31, 2016 by Institut Mines-Télécom, we asked him to shed some light on the issues and limitations relating to the use of biomass.

 

 

Will green gold eventually replace black gold? Will oil’s overwhelming domination be challenged by the biological resources all around us? The Brent Crude oil price per barrel, which has been falling for over a year, seems to leave little hope for any competition. Yet biomass — all organic matter of animal and plant origin — could very well put up a fight. The reasons for its appeal are indeed more complex than issues of economic competition in the energy and materials markets, sectors predominantly supplied by hydrocarbons and their derivatives. Whether oil prices are up or down, it nevertheless remains a “limited resource, from which we will need to break free eventually,” says Patrick Navard, a researcher in bio-sourced materials at Mines ParisTech. This desire to find alternative solutions is also motivated by the growing appeal among citizens for eco-labeled products. “We all want to leave a cleaner planet for our children,” adds this expert in bio-inspired materials, putting environmental issues back at the heart of the matter. This dimension is already integrated by brands into their product marketing, in which they boast about compliance with countless ISO standards and ever lower CO2 emissions.

While these driving forces for an ecological transition require massive efforts over a relatively long period of time — a new vision of society is rarely accepted immediately and unanimously — they are supported by more practical aspects. Biomass is not simply a replacement solution: it is also a catalyst for innovation. “Certain products obtained from renewable resources are much better than those manufactured using fossil resources,” Patrick Navard argues. “A good example of this is cars: composite materials that use natural fibers are 15 to 20% lighter than those made with glass fiber.” This boost in performance from the bio-sourced material, in this case, is directly accompanied by a decrease in shipping and handling costs and, eventually, a reduced carbon footprint — a lighter car that emits less CO2 per kilometer.

 

Biomass – an opportunity for materials

The materials industry is one of the sectors that could, like energy, be greatly impacted by this transition. Polymers, which are components of plastic materials, are in the vanguard of this change. But there is still a long way to go. As Patrick Navard likes to say: “The use of biomass to develop plastic materials is developing rapidly, but it started out at a very low level.” Bio-sourced polymers currently only represent 0.1% of the polymers used around the world. And yet their properties are not that different. In fact, they are similar. “Whether we are talking about using oil or biomass to produce polymers, in the end it boils down to the same thing,” the researcher explains. Because oil, after all, is nothing other than biomass that has been buried in the ground and digested by the earth through chemical and biological processes over millions of years.

 

La production mondiale de matière plastique s'élève à 300 millions de tonnes. La biomasse pourrait devenir une source de polymères dans le futur et alimenter ce marché.

The global production of plastic materials amounts to 300 million metric tonnes. The use of biomass as a polymer source could therefore increase considerably to meet the growing demand (250 million in 2009, 204 million in 2002).

 

In Patrick Navard’s opinion, making any kind of polymer using renewable resources is perfectly conceivable: “The plant fibers must simply be broken down to form chemical building blocks, thus reproducing what nature does over a much longer period of time.” Such products already exist: polyethylene, for example, can be synthesized using cane sugar. Likewise, cornstarch can initiate the synthesis of polylactic acid, a biodegradable polymer used for food packaging. Another highly prized natural molecule is already used in industry: cellulose. It represents over 50% of the plant biomass and regularly supplies pulp mills.

 

Biomass refineries

Yet a problem remains in all these syntheses initiated by natural molecules: once the desired substance has been extracted, what is done with the remainder of the used plant matter? Cellulose is a major component of plants, but it is not the only molecule. The others, like lignin and hemicellulose, are mostly burned in current industrial practices. And yet lignin plays an important role in the rigidity of plants and could be recovered. “Lignin is the most abundant source of aromatic compounds on earth, and yet it is currently almost completely untapped, while industry uses many synthetic aromatic substances, which are particularly polluting,” regrets Patrick Navard. The lignin molecule present in wood could therefore be a precursor to the development of products that are in high demand. However, the researcher cautions that “Many research projects around the world are trying to exploit lignin and, so far, with little success, because it is a complex molecule.”

This leaves us with the idea of recovering compounds currently considered as waste. This principle is at the heart of the biorefinery concept. It involves modeling the oil processing procedures, in which the various molecules composing the crude oil are separated: the heavy fractions are used for bitumen and the lighter fractions become solvents for the chemical industry. Nothing is wasted from this precious black gold. So why discard the biomass by-products? This example illustrates the advantages of waste recovery: when Miscanthus, a herbaceous plant, is harvested, an initial sifting procedure removes the sediments. Rather than discarding these sediments, “they can be used in the development of composite materials,” Patrick Navard explains.

 

In addition to the sediments obtained from screening, the Miscanthus plant is used to reinforce composite materials. The material’s mechanical properties vary according to the chosen species.

 

Environmental impact and land management

The prospects presented by biorefineries must also be tempered with caution. Though their development may be synonymous with more environmentally sustainable production, since it is based on renewable resources, this does not necessarily mean the environmental impact will be reduced. “If highly polluting chemistry must be used to recover the plant’s resources, the environmental impact is not reduced at all,” Patrick Navard cautions. The researcher illustrates these remarks with a comparative impact study carried out at two cellulose thread factories owned by the same company, one in Austria, and the other in Indonesia. Despite following the same manufacturing process, the Austrian factory was less polluting. The reason for this was the distance from the forest from which the trees were obtained. In Indonesia, the forest was located several hundred kilometers away, significantly increasing the carbon footprint from the transportation of the wood, whereas the Austrian factory used a more local supply. “This problem does not exist for the oil industry, since it does not cost a lot to push crude oil through a pipe. But wood can’t be transported in the same way,” Patrick Navard explains.

The issue of geographical location does not just apply to biorefinery sites. With the use of biomass comes the problem of land being used for purposes other than agri-food production. This issue already arose several years ago with the cultivation of crops for biofuel, which led to highly questionable results. Indeed, numerous problems exist – from humanitarian disasters caused by the increased price of corn, to the simple impossibility, given the yields, of allocating enough land. This possibility of producing first-generation biofuels is flawed for many reasons, and is not ethical. “The problem is different for materials,” explains Patrick Navard. “We do not need to produce as many crops in this case. While fuel constitutes one of the biggest oil products, materials only use the equivalent of a few percentage points of crude oil.” Therefore, less land is required to redistribute the demand for materials to biomass than would be required to meet the demand for fuel. In addition, the cultivation of crops used for dual purposes can be envisioned, combining food purposes with the production of resources for the development of materials.

 

Convincing farmers and industrialists

Yet there is still an obstacle to the development of biorefineries and the use of biomass: their appeal to farmers and industrialists. “Farmers will not go into this business unless they are certain they will be able to sell their crops, and industrialists will not develop these products unless they are sure they can buy at a reasonable price,” explains Patrick Navard. The structuring of these sectors is therefore the key issue. In Germany, agreements have been made between farmers and manufacturers, enabling the launch of these initiatives. But not all the initiatives are successful. In South America, the industry based on the Curauá plant did not develop to the expected extent due to a lack of stability: the presence of only one distributor on the market cannot guarantee the security of production. In France, Patrick Navard assures us that initiatives are emerging, but adds that things are slow and difficult at times: “There’s a lot of red tape to get through, at the regional, departmental and municipal levels.” Yet time seems to be running out. On the one hand, oil resources are diminishing, and prices will increase due to the ever-growing demand, which will speed up the ecological and environmental transition. But on the other hand, CO2 emissions are skyrocketing, leaving our societies with even less time to limit the irreversible impacts of our activities.

Read more on our blog

Agro-based composite materials – a Mines area of expertise

Vabhyogaz

Vabhyogaz uses our waste to produce hydrogen

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Hydrogen is a resource that is prized for its applications in the chemical industry and for its role in the fuel cells used in electric vehicles. Vabhyogaz – a project initiated by Didier Grouset, a researcher at Mines Albi – proposes to convert biogas from our waste into hydrogen. The project, which began nearly ten years ago, is now entering its third and final phase of development in 2016.

 

Over two months after the 21st Conference of the Parties to the United Nations Framework Convention on Climate Change (COP 21), are any concrete solutions for limiting CO2 really emerging? Near Albi in the South West of France in any case, the Vabhyogaz project is quietly entering its third phase of development. This project initiated in 2007 has the goal of converting biogas from waste into hydrogen. This resource is particularly sought after for powering vehicle fuel cells, while only emitting water vapor.

Initially, Vabhyogaz stemmed from cooperation between N-GHY, an SME created by Didier Grouset as a spin-off from Mines Albi, specializing in the hydrogen industry, and TRIFYL, the Tarn regional federation for the recovery of household waste. The first stage of the project united regional partners together around TRIFYL and N-GHY, including Mines-Albi and Phyrénées, an association initiated in 2007 by these three entities, with the aim of bringing together a community focusing on hydrogen issues in the Languedoc-Roussillon-Midi-Pyrénées region. “To take an interest in the entire hydrogen value chain, and bring local stakeholders together to establish the originality of the Vabhyogaz concept,” explains Didier Grouset, a researcher at Mines Albi. The project now includes many different partners: SMEs, public authorities, and subsidiaries of multinational groups*.

 

Le projet Vabhyogaz a été identifié comme "Solution climat" lors de la COP21 et présenté au Grand Palais à Paris.

The Vabhyogaz project was identified as a “Climate solution” at COP21 and was presented at the Grand Palais in Paris.

 

The process of converting waste into hydrogen starts with a natural process: methanization. In an oxygen-deficient environment, micro-organisms break down our waste and give off a gas: a mixture of carbon dioxide (CO2) and methane (CH4). This mix is what is what we call “biogas”. To speed up this process, which can last around thirty years in a landfill, Trifyl uses a bioreactor, reducing the biogas production time to fifteen years. The above-ground anaerobic fermentation of our domestic, agricultural and food-processing waste, using a biogas plant, will also produce biogas in only a few days.

“The biogas is then purified by removing the minor pollutant compounds, such as hydrogen sulfide and, usually, CO2 is removed as well, but the unique aspect of the Vabhyogaz process is that it eliminates this costly step,” explains Didier Grouset. The chemist adds: “Instead, we take the methane-carbon dioxide directly and place it under 15 bar of pressure at 900°C by introducing water vapor, all in a nickel-based catalyst.” The methane and water therefore react to form carbon monoxide (CO) and the coveted hydrogen (H2). This reaction is completed by the reaction of CO with the remaining water vapor at 200 °C, again forming hydrogen and CO2. The hydrogen produced therefore comes from the waste and water that have reacted.

 

Extra-pure hydrogen

Once the hydrogen synthesis process is completed, it is purified to obtain a purity of 99.995%. “This is essential for complying with the supply standard for hydrogen fuel cells, and guaranteeing their long-term service life,” warns Didier Grouset. Mastering this procedure brought an end to the second phase of the Vabhyogaz project, which was completed in 2014. “Today, our partners have a prototype capable of producing 10 kg of hydrogen per day,” the researcher notes. This is enough to power a few hydrogen-powered electric Kangoo vehicles that can travel over 200 km per day. Didier Grouset recognizes that this “is still small compared to our future needs,” and that a production unit “becomes advantageous, in other words, economically profitable, starting at 100 kg of hydrogen per day.”

This explains the upgrade scheduled to take place during the third phase of the Vabhyogaz project, which will begin in early 2016, as part of the Investments for the Future program. This phase will be aimed at commercializing units with production capacities ranging between 100 and 800 kg of hydrogen per day. These units could then become distributed production units, each able to supply several operators at the local level. The thinking on how to transport the hydrogen resource will also be included in this phase. Containers of tanks made of composite materials, which are lighter and better adapted to transporting hydrogen, are being developed as part of the project.

 

What does the future hold for the hydrogen energy sector?

Identified as a “climate solution” at COP21 where it was presented at the Grand Palais in Paris, the Vabhyogaz project has a promising future. But its viability is based just as much on the quality of the project, as on the need for changes in the use of hydrogen as energy. Didier Grouset seems optimistic about this, initially mentioning a national specificity that has led to the development of less expensive hydrogen-powered vehicles: “One of France’s distinctive practices is the use of hydrogen fuel cells as battery range extenders, and not as the main power supply for the electric motor.” For French manufacturers, fuel cells used to recharge the battery only need to produce the average power required for the electric vehicle, which has a motor that is primarily powered by the battery. This is different from the practices of the foreign competitors, which have favored the use of a fuel cell capable of supplying the maximum power for the motor. The researcher helps explain the context: “In the first situation, the fuel cell must have an output of 5 kW, as opposed to 100 kW in the second.”

But hydrogen energy is up against a very difficult opponent: oil. “With the Vabhyogaz solution, the price becomes competitive,” says Didier Grouset. In numbers, this would translate as a target of one kilogram of hydrogen costing €8 including tax, keeping in mind that it takes approximately 1 kg of hydrogen to travel 100 km. But this target is set in comparison to a liter of diesel fuel at €1.20 including tax. And, the current context of falling oil prices appears to make this an uneven fight. Still, Vabhyogaz is not doomed to failure. “The motivation shown by users remains a key to success,” he declares confidently. The project can benefit from its history in this area, as the researcher reminds us: “Around Albi, the hydrogen sector has been a topic of conversation since 2007; this is especially due to the Phyrénées association.” Vabhyogaz will therefore seek to target company vehicle fleets during its third phase.

 

Hydrogen, a resource for industry

The automotive sector is not the only industry targeted by this project. Although fuel cells are the most remarkable application of hydrogen, another application also exists, and is just as important: the chemical industry. The manufacture of semiconductors – key components in microelectronic equipment – requires large quantities of hydrogen. The same applies to the production of high-quality glass and the heat treatment of metals. However, “there are very few production sites for commercial hydrogen, resulting in long transport distances,” explains Didier Grouset. And yet, many industrial needs exist, ranging between 100 kg and 500 kg of hydrogen per day. The production units developed by Vabhyogaz could therefore directly supply the stakeholders in question.

In order to reach this stage, phase 3 of the Vabhyogaz project will also include life-cycle analyses and energy optimization studies for all steps in the procedure. This will specifically involve confirming that consumption has decreased for the hydrogen distribution units and for its transport, with the aim of reducing the environmental impact of the production chain for the conversion of biogas into hydrogen. Vabhyogaz is truly an environmentally motivated project, in terms of the purpose of hydrogen use, and also throughout the entire hydrogen value chain.

Read more on our blog: PREVER, residue turned into energy

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Vabhyogaz, a collaborative success story

The Vabhyogaz 2 project has been coordinated by ALBHYON, a subsidiary of HERA France (HERA group, which originated in Spain). ALBHYON has continued the work of N-GHY in partnership with TRIFYL. This project was partially funded by ADEME as part of the TITEC program.

Following the proof of concept for phase 2, HERA decided to develop a range of products for producing and distributing hydrogen from renewable sources. This is the goal of phase 3 of the Vabhyogaz 3 project, which includes the following partners:

• HERA-France and its subsidiary ALBHYON, project coordinator
• HP SYSTEMS, an SME from La Rochelle
• WH2, an SME from Lyon
• TRIFYL, the Tarn regional federation for the recovery of household waste
• EMTA, a subsidiary of SARP Industrie, (VEOLIA group)
• Mines Albi

This project will last 4 years, and was submitted in the Storage and Energy Conversion call for projects of the Investments for the Future program in December 2015. The total budget for the project is €9.76 million and €4.47 million of funding has been requested (largely refundable). The application has been submitted for examination by ADEME. [/box]

Ingrid Bazin, Mines Alès, biocapteurs, herbicides

Biosensors for monitoring herbicides in water

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Water preservation and management involves detecting its pollutants. Among those most frequently found in surface water and groundwater are weed-killers, such as the well-known glyphosate. At Mines Alès, Ingrid Bazin is working on developing innovative bioreceptors to monitor these small molecules, with the aim of one day providing the water industry with cutting-edge biosensors.

 

The number of water pollutants is rising, including for example heavy metals, pesticides and preservatives. More than 800 substances are listed as being potentially harmful, 43 of which are regulated in France. The European Water Framework Directive of 20 October 2000, transcribed in France by the Law of 21 April 2004, aims to restore surface water and groundwater to good chemical and ecological condition by 2015, and put a stop to the discharge of certain dangerous substances – the 50 most urgent to eradicate – by 2020. The Laboratory for environmental industrial engineering (LGEI) at Mines Alès, and in particular the ESAH (Water, Anthropogenic Systems and Hydro Systems) team, works on diagnosis, measurement and analysis of environmental pollutants by developing biodetection tools (bioreceptors and biosensors). The ESAH team is principally made up of analytical chemists and it is strongly involved in the water competitive cluster in Montpellier as well as in the Montpellier Institute for Water and the Environment. “Our quality of life depends a lot on our environment” Ingrid Bazin reminds us, “and our initial objective is to improve the quality of our water-based ecosystems, as there are direct consequences on our level of health”. Herbicides are endocrine disruptors and have a direct impact on our hormone system, which is the cause of the famous feminization process in animal populations, notably among fish, which leads to an imbalance in the ecosystem and potentially catastrophic long term consequences for biodiversity and our health.

 

Ingrid Bazin, biocapteurs, Mines Alès

Field kit for detecting environmental pollutant

Glyphosate, the most commonly found herbicide in water

The ESAH team’s research is applied. “We work directly with water industry players such as Veolia and BRL (a construction company in Bas-Rhône and Languedoc) with a view to meeting the challenges facing them in the detection of water pollutants” the researcher explains. While efficient and regulated physico-chemical analysis tools are already available, the aim is now to demonstrate the benefits of developing biodetection tools in the environmental sector. Two major requirements are apparent: evaluating the overall harmfulness i.e. the effects of the pollutants in water on humans and the ecosystem, and detecting some molecules that present a challenge for treatment. This is the case, for example, of glyphosate and its metabolite, AMPA. “Glyphosate is not the most harmful herbicide found in the environment, but it is the most common because it is still used by a large number of people. Industrial firms are obliged to monitor it, particularly in sectors that produce drinking water which must not exceed a concentration of 0.1 µg/l” says Ingrid Bazin.

 

An innovative idea awarded a prize in 2014

The aim is not to instantly detect pollutants like atrazine or hydrocarbons, since analytical chemistry already does this very well, but to optimize monitoring of the water cycle using biodetection tools that are simple to use, robust and inexpensive. The biodetection test must also be sensitive enough. A biological recognition element (i.e. a bioreceptor) with a strong affinity with the molecule in question is required to achieve this. Glyphosate and its metabolite, AMPA, are particularly small molecules for which “standard” detection using enzymatic biodereceptors, antibodies or small DNA fragments is difficult. “My idea is to use peptides of 6 to 15 amino acids, or even small proteins of 80 to 100 amino acids as bioreceptors in order to detect small molecules for which it is difficult to develop an antibody” explains Ingrid Bazin. In 2014 the idea won the “Researchers of the future” grant awarded by the Languedoc-Roussillon region, destined to support projects of excellence by young researchers (under 38 years). The prize money has allowed funding on the subject for the ESAH team’s research work for a year and a half, and notably testing the efficiency of detection of small molecules using a peptide sequence developed in the laboratory (the peptide or small protein that offers the best capacity for binding to glyphosate molecules).

Ingrid Bazin, biocapteurs, herbicides

Cultivating bacteria in a petri dish of agar-agar

The next stage will consist in developing a rapid test that can be used on the ground, in the form of a test strip that lights up when it comes into contact with glyphosate and AMPA. Then, in time, “all in one” biosensors will be designed to enable the immediate assessment of the concentration of herbicides – available online, what is more. Additionally, the ESAH team is currently a partner of an ANR (French National Research Agency) project Combitox, that is managed by the CEA Cadarache (Atomic Energy Commission). This aim of this R&D project, due to finish at the end of 2015, is to develop an online multi-parameter instrument for continual biological measurement of three types of water pollutant: fecal bacteria, heavy metals and environmental toxins, which are what Ingrid Bazin and her team are interested in. “The innovative feature here is the creation of a biological recognition device: the peptide sequence, which will be perfect for detecting small molecules. It is a real challenge, even though the idea is not a new one, since the design and development of a biosensor is a very lengthy process and requires multiple laboratory and field trials” the researcher concludes. The final aim is to improve water quality and the quality of life of consumers.

 

Ingrid Bazin, Mines Alès

Ingrid Bazin started her career in the biomedical sector in the Paris region. After finishing her preparatory studies she entered the University of Versailles in 1996 and then Pierre and Marie Curie University (Paris 6) in 1999, where she studied for a postgraduate advanced diploma in the Biology of Aging. She entered R&D in genetic engineering, researching new drugs to fight cancer and, as one thing led to another, she was drawn into the environmental sector, but this time in the south of France where she studied for a PhD in molecular biology and plant physiology at the CEA Cadarache (Atomic Energy Commission). “My work entailed studying the genes that lead to the accumulation of heavy metals in plants, in order to design tools for removing pollution from soils” she explains.

After postgraduate research at ISTMT (Institute of the Science and Technology of Medicine of Toulouse) and having participated in the start-up of the Grenoble-based company Smartox, which specializes in the synthesis of peptides for therapeutic uses, she joined Mines Alès in 2009 as a Research Professor and in 2015 received her Accreditation to Lead Research (HDR). Working in the Laboratory for environmental industrial engineering (LGEI) in the Water, Anthropogenic Systems and Hydro Systems (ESAH) team, Ingrid Bazin applies her knowledge as a biologist to the development of new tools for biodetection of environmental pollutants.

 

 

Pollution control by constructed wetlands: An expanding French industry

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The ability of wetland areas to retain and treat a wide variety of pollutants in urban and rural areas has been known about for a number of years. Understanding how they work has facilitated the creation of biofilters such as constructed wetlands. At Mines Nantes, researcher Florent Chazarenc has studied these systems over lengthy periods and created solutions adapted to different types of wastewater. He aims to improve the French domestic wastewater treatment industry, an area of expertise that is starting to be exported.

 

 

Wastewater treatment tailored to the pollutant

Wastewater can be a by-product of human uses, whether domestic, agricultural or industrial, or can come in the form of surface run-off water. It contains organics, phosphates and nitrates, heavy metals, hydrocarbons and even drugs. “My research consists in developing wastewater treatment solutions adapted to situations which currently don’t have any: it all depends on the nature of the effluent, but the carrier is always water,” explains Florent Chazarenc. The researcher mainly works with a category of treatment processes known as constructed wetlands , which is a wastewater treatment system using macrophyte plants (aquatic plants with underwater or floating organs), substrate materials (sand, gravel etc.) and colonized by micro-organisms. The technique involves creating an artificial wetland that is used as a biofilter, commonly called a reed bed filter or constructed wetland.

In constructeRacines_Florent_Chazarencd wetlands the water is purified through a combination of physical, biological or chemical processes. Plants with a dense root structure offer good physical filtering, while micro-organisms growing on their surface produce biological activity that decomposes pollutants such as nitrates and transforms them into nitrogen gas. “When there’s nothing left to do biologically, we move on to chemicals”, which is the case for phosphates. “This combination of all three is called chameleon technology, Florent continues, “which entails creating biological and chemical-physics reactors adapted to all categories of wastewater”, regardless of climate conditions (temperature, amount of sun) or the liquid pressure and organic load.

Research into all kinds of solutions has been fueled by this variety of wastewater types. Florent Chazarenc and his team work on several projects at the same time, including developing systems to refurbish old extensive wastewater treatment plants built in the 1980s and give them a new lease of life, treating leachate in Africa by getting rid of pollutants through electrolysis and/or photocatalysis in combination with reed bed filters, and protecting natural wetlands with constructed wetlands.

 

Improving the French domestic wastewater treatment industry

“Since the 1980s and the initiative by IRSTEA in Lyon, more than 3,500 reed bed filters have been introduced in France for towns and villages with fewer than 2,000 inhabitants.” Florent Chazarenc has contributed to the sharp rise in these installations since the 1990s. In France, the process is called a “vertical flow filter” because the wastewater is spread out at the surface and filtered down through the bed via percolation. However, the fact that a surface area of 2 to 3 m2 is needed per inhabitant can sometimes hinder the development of the sector. Although improvements do exist to reduce this to 1 m2 or even 0.5 m2 per inhabitant, they have not yet been employed in association with large urban areas or wastewater from the food industry.

 

The double drainage system is only present in the compact channel, limited to the 1st stage, which is deeper.

The double drainage system is only present in the compact channel, limited to the 1st stage, which is deeper.

 

Florent has studied results from more than 150 of these installations over 10 years, looking at systems with two or just one treatment stage. The researcher aims to improve the French domestic wastewater treatment industry, which is now starting to be used abroad. “We are now very good at treating suspended matter or organic matter, but we could do better on nutrients like phosphates or nitrates”, he explains. The idea is to employ the same approach used in process engineering: “intensify the extensive system”.

Two approaches known as semi-extensive are being studied. The first consists in intensifying the pollutant-removal process using chemical techniques. The European project called Slasorb was conducted in this framework, proposing an innovative solution for extensive treatment of phosphates using a co-product of the metallurgic industry as reactive matter. “This project needs its first industrial reference”, added the researcher, who hopes to promote its disruptive technology. The second approach reduces the reaction volume and the surface area taken up by the process. This can be done through forced aeration or by transporting the effluent from the outlet back to the start of the process – recirculation; both these methods require energy, which may be produced from renewable sources (wind turbines or solar energy etc.).

Florent is interested in many other types of wastewater which can be treated with constructed wetlands and specific installations, including industrial wastewater (pastry-making, chocolate manufacturing, fizzy drinks manufacturers etc.) and sludge.

[box type=”shadow” align=”” class=”” width=””]From the lab to on-site testing

Filtres plantés de roseaux, Florent ChazarencIt takes one to two years for a vertical flow reed bed filter to reach its optimum efficiency. These long periods require work on several projects at the same time, in partnership with microstructures, SMEs or large groups. Some projects involve fundamental research, while others, which are greater in number, are focused on applied research with rapid dissemination. In this framework the technology readiness level is an important indicator for the solutions studied, from level 1: “basic principle observed”, to level 9: “real system proved”. Most of Florent Chazarenc’s work is situated between levels 5 and 7, and a few on levels 3 and 4.[/box]

 

Surface run-off water also needs treating

While significant financing is earmarked for wastewater treatment, rainwater treatment has only recently started receiving funding. This water is contaminated through the surface run-off process, washing the ground and coming into contact with contaminated surfaces, for example roads polluted by the car tire wear. “There is still a little atmospheric pollution in certain countries (acid rain)” the researcher explains, “but this is diminishing fairly quickly”. In rural areas, on the other hand, excess fertilizer is washed away by the rain.

Once again “the solution is to use plants as a pollution control factory”. For example, in partnership with highway management companies, the run-off water collected in holding basins can be treated by adding floating wetlands to improve their performance. Another example is processes that encourage sedimentation, with ditches containing plants or grass growing in them. “There is an international policy of no longer discharging this run-off water directly into rivers, but instead treating it first”, Florent is pleased to point out, mentioning among others the Water Framework Directive [2000/60/EEC] in Europe. Nevertheless, there is not as much legislative pressure in this field and potential financial partners, for example, are still few in number.

Although the effectiveness of reed bed filters is widely acknowledged, it is the acceptance of their benefits by the general public that will lead to their use on a large scale.

 

Petit_Portrait_Florent_Chazarenc_jauneAn Associate Professor at Mines Nantes, Florent Chazarenc contributed as early as in the 1990s to the rise in the use of processes for treating wastewater using reed bed filters, through his engineering internship and PhD in Environmental Engineering at the University of Savoie. He carried out his post-graduate research jointly at Polytechnique Montréal and at Institut de recherche en biologie végétale in Montréal, before returning to France in 2007 where he took his Accreditation to Lead Research in 2013.

A marathon-runner and triathlete, he understands what it means to work over the long term and to combine processes. He and his team, “a group which has enabled me to carry out these trials over all these years”, have earned recognition through a large number of projects. Having organized the 5th WETPOL conference (International Symposium on Wetland Pollutant Dynamics and Control) in 2013 in Nantes, he is also strongly involved in specialist groups of the IWA (International Water Association) on the subject of reed bed filters and water pollution control. Through these activities he aims to facilitate the sharing and dissemination of information, help and guide young researchers and promote solutions beyond their initial field, such as the sale of finishing zones at the end of traditional stations.

Marine pollution

Marine pollution as seen by ultrafast cameras

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Ultrafast cameras unveil processes that are invisible to the naked eye. At Mines Alès, Pierre Slangen, a specialist in applied optics, uses them to build advanced technology devices and thus to understand how gases and liquids are diffused during environmental disasters.

 

 

Certain physical phenomena occur in such small time scales that they remain practically invisible without the use of sophisticated cameras and state-of-the-art laser devices. At Mines Alès, Pierre Slangen’s field of specialism has developed a research theme in the field of applied optics in new technology, for visualizing pollutants in aquatic environments. As early as 1993, before earning his State Doctorate in Belgium, he characterized materials through the use of holograms, measuring movements of just 0.5 µm. He continued his work in this field in 1995 when he joined Mines Alès. In 2003 he collaborated with a team as part of the Clara project with Cedre, Ifremer, Météo France and Inéris that was building a new IT system designed to help decision-making to deal with chemical substance spills at sea. All that remained was to observe the development of such spills in the water in detail. There is increasing research into viewing the invisible, from traces of nanoparticles to certain gases and chemical products, thanks to the possibilities offered today by ultrafast cameras. “They enable us to discover a significant amount of extreme processes whereby optics, although it does not always enable us to see, at least enables us to distinguish”, Pierre Slangen explains.

 

 Evaluating and anticipating industrial risks

Stakeholders in the oil and gas industry have been expressing their need for modelling tools for offshore leaks for several years. The accident at the Deepwater Horizon rig in 2010 highlighted the importance of such detailed knowledge of underwater phenomena and their consequences at the surface. In 2011 the METANE (Modeling undErwater gas/oil blowouT And lNg lEak) collaborative project received a double accreditation from the French Pôle Mer Bretagne Atlantique and Pôle Mer Méditerranée, as well as funding from the FUI (French Unique Interministerial Fund) to develop such a decision-making tool for industrial hazards linked to underwater leaks of oil, natural gas or liquefied natural gas (LNG) at sea. This 3-year project has received total financial support of €330 k. METANE is also a grouping of major public and private-sector actors, each of whom contribute their own expertise: Alyotech, Cedre, Nymphea Environnement, Mines Alès and GDF SUEZ.
Ultimately, the developed tool enables plans to be defined for the prevention and management of disasters, focused on the risk of accidents in relation to underwater hydrocarbon leaks. In order to calibrate and validate the digital model the project required laboratory trials both at Mines Alès and in situ at the Cedre in Brest. These trials allowed the trajectory, dissolution and rising speed of gas bubbles or oil droplets in the water column to be studied using optics. The project is focused on safety and the environment and aims to provide an understanding of the risks for personnel and equipment of off-shore installations.

Ultrafast imaging

Now essential in the fight against marine pollution in order to detect minute drops of pollutants or the ejection of gases with highly complex dynamics, these high-frequency cameras offer a better understanding of the way different fluids mix with each other. When a chemical tanker sinks, the products it was transporting can indeed behave differently within the water column. These non-linear fluid mechanics, which occur across very short periods of time, a matter of just milliseconds for some, must therefore be observed in detail in laboratories using experimental trials. Thanks to these cutting edge cameras it is now possible to ‘stretch out’ periods of time. The frequency of frames can be as much as a million per second: a far cry from the cameras for use by the general public, which rarely exceed 50 frames per second! The highest frequencies allow us to see how matter structures itself in space.

The ultrafast cameras used by Pierre Slangen and his team, which sometimes work at a rate that is much faster than the speed of time as we perceive it, allow micro-processes to be filmed and then viewed in fine detail. Slowing down time allows us to make out what happens in each time interval, from microseconds to seconds, something that is essential for understanding the dynamics of how chemical products spread when a ship sinks or during the explosion of a gas contained in a pipe. For Laurent Aprin and Frédéric Heymes, the team’s researchers in fluid dynamics, the results obtained in the field of optics allow a better understanding of how a chemical product diffuses as it rises through extreme temperature and pressure conditions when a ship sinks in deep water. This leads to an improvement in predictions of the amount of product to be handled by clean-up operations at the surface and in the air surrounding the site where diffusion is to be controlled (explosiveness, toxicity etc.)

 

Illumination using lasers

Such high speed imagery requires suitable illumination, so Pierre Slangen’s team builds complete devices where the light is supplied by superluminescent LEDs, or by laser pulses that emit light beams in the form of flashes. These devices vary according to the problem: an oil droplet mixing with water cannot be compared to the change in shape of a piece of laminate sheet metal for a vehicle, the artificial limb of a Paralympic athlete such as Dominique André at the Olympic Games in Sydney in 2000, or the device set up by the Zéline Zonzon dance company who wanted to show that dancers perceive and displace the air around them. “I used to be a developer of specific techniques, today I am a builder. I always tell my students that if you do not master the contents of a box, you will not master the box”, Pierre Slangen explains.

The work does not stop here, however. Not satisfied with building the best devices, Pierre Slangen wants to qualify them. He and his team mathematically quantify these methods from a metrological perspective and evaluate the deterioration of information linked to measurement uncertainties such as noise inherent to the coherence of the laser source and distortions that are intrinsic to the cameras and their lenses.

The advantage of these optics techniques for field measurements, especially in terms of diffuse light, is that they are well adapted to non-destructive testing and the measuring of fields of movement in 3D for solids and fluids thanks to their high level of sensitivity and excellent spatial resolution. The use of mechanical trials based on techniques like the correlation of images and the measurement of interference in diffuse light, produces cinematic fields which enable identification of the behavior of the materials studied.

Pierre Slangen’s next challenge is to observe larger fields (1 m2) using a resolution of 1 µm. This would require fast sensors of tens of millions of pixels… which don’t exist yet. The idea is to emulate the astrophysicists in Chili who, with the European Southern Observatory’s Very Large Telescope, are testing out multiplexing. They put together small images with an excellent resolution. Understanding of micro-phenomena is being added to that of the infinitely big.

 

Portrait_PS_pour_blogPierre Slangen entered the field of visualization techniques during his Master’s in Optoelectronics. At the time he was keenly interested in the creation of holograms: images in three dimensions that do not require special glasses. After a State Doctorate thesis in 1995 at the Belgian University of Liège, he is now a Research Professor at Mines Alès and has been accredited to lead research since 2013. He joined the Institut des Sciences des Risques team at Mines Alès in 2010. He is currently leading contractual work on the analysis of fragmented jets of liquid using imaging, confinement loss through very high velocity impact in reservoirs, and the study of atmospheric transfer as well as oil or liquefied natural gas (LNG) leaks at sea. He shares his knowledge through his lessons on sensors, applied optics and holography as well as by participating in television programs. To find out more

Editor: Umaps

Responsible lighting: the secrets to a good eco-innovation strategy

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On February 11, 2015 an open workshop will be held in Brussels to present the results of the European cycLED project. This research program has supported four SMEs in the lighting sector in their eco-innovation projects aimed at designing more efficient LEDs, from both an economic and an ecological point of view. Cédric Gossart, a researcher at Télécom École de Management, has studied the barriers that hinder eco-innovation in the LED industry, and the ways to overcome them.

 

“10 years from now, we will only use LEDs. They are beginning to replace all lighting technology.” The European cycLED project (Cycling resources embedded in systems containing Light Emitting Diodes) was therefore aimed at assessing the opportunities for creating new products and services based on LED technology. With €4 million of funding, as part of the FP7 program, it brings together 13 European organizations, and is led by Fraunhofer IZM. The project’s original approach involved supporting four SMEs in the lighting industry (Braun Lighting, ETAP, ONA and Riva) and helping them to eco-design more environmentally friendly and innovative LEDs that were adapted to their needs.

 

Reducing environmental impacts while creating value

Braun Lighting Solutions needed small urban lighting modules requiring little maintenance and being easy to repair. ETAP wanted to develop an LED with a long service life that could withstand extreme conditions: for example, corrosion due to exhaust gases in parking lots. ONA wanted a product that would be almost completely recyclable, with components that could be reused. Finally, Riva developed LEDs for warehouse lighting and a new business model: selling a lighting service rather than simply selling lighting products. “The environmental benefit,” Cédric Gossart explains, “is that this encourages the company to make its lamps last as long as possible. It’s a way of combating obsolescence.”

Although they pollute less than older light bulbs, LEDs are still not perfect. They contain rare and dangerous metals that are difficult to recycle. “Currently, if you want to recycle the indium and gallium in LEDs, you have to choose to recover one or the other. One of the partners, Umicore, is working on designing a way to separate them. At the start of the project, we didn’t even know if this was possible,” explains Cédric Gossart. This would both reduce the environmental impact and reduce the risk of shortages of these raw materials.

Social science researchers helped the SMEs to ensure their innovations would be viable and to develop true innovation strategies. Three European research institutes participated in the project. Ecodesign Centre in Wales (United Kingdom) drafted recommendations for managing rare resources throughout the LED product life cycle. Sirris, the Belgian collective center for the technology industry, worked on business models applied to eco-innovation. Finally, Cédric Gossart from Télécom École de management, worked with his team (KIND) to analyze obstacles that hinder the development of eco-innovation in Europe, and sought solutions to overcome these obstacles.

 

Overcoming the barriers to eco-innovation

“Eco-innovation allows new markets to be created and improves a company’s image, while also motivating employees and attracting talent from outside the company, because it meets a social need and reduces the environmental impacts.” Yet, despite these advantages, many barriers hinder companies that would like to adopt this approach. All in all, Cédric Gossart and his team of researchers listed and classified 144 obstacles, which are not specific to the lighting industry. “We then asked the four SMEs to assess them. 60% were deemed irrelevant.” The others were thoroughly analyzed, and the consortium then worked to provide solutions.

The main obstacle for companies is technological. It concerns the choice of the “driver”: the equipment that powers and controls the LED. “Although an LED can last over 10 years*, the driver is generally only guaranteed between three and five years, and can last an even shorter time. The drivers’ fragility constitutes one of the reasons for the rapid decline of an LED’s performance, contributing to the poor reputation of LEDs when they were first rolled out.” Certain SMEs have therefore decided to produce their own drivers in-house, in order to obtain high-performance LEDs. Others have chosen to train their staff to identify a good driver. “We sought solutions to help the SMEs with the problems they could not solve on their own.” The cycLED consortium therefore recruited the help of the Lighting Europe association in order to implement procedures for verifying the certification of the lighting products. As a result, on January 7, 2015, the association called for the reinforcement of pan-European cooperation and improved market surveillance.

This analysis also revealed new barriers hindering eco-innovation. “We realized that one of the tools aimed at supporting innovation – the patent – could in fact hinder it. LEDs are complex technological objects, and designing them requires the integration of several fields of knowledge, leading to inventions that are patented by competing companies.” It is therefore impossible to design a more innovative LED without getting involved in intellectual property disputes. To overcome this barrier, Cédric Gossart favors “a more open knowledge protection system.”

 

A workshop on understanding how to eco-innovate

Today, the cycLED project is entering a new phase. On February 11, 2015, an open workshop will be held in Brussels, open to all those involved in the lighting industry, as well as any companies interested in eco-innovation. The SMEs will present the results from the project – the LEDs they eco-designed – and will explain how they got started with this approach. “If it weren’t for this European project, these four SMEs would probably not have adopted this eco-innovation approach. Now they all intend to do more.” The idea is for these four experiments, and the tools developed by the researchers, to help other companies, including those from other sectors. This is the case for the obstacle analysis carried out by Cédric Gossart: “Because the project was aimed at helping the entire European lighting industry to adopt an eco-innovation approach, we are now expanding this eco-innovation obstacle analysis to include other companies in the sector via an online questionnaire.” With the secret hope of one day witnessing the creation of the ultimate eco-designed LED: a zero impact LED that is completely recyclable, and designed according to the cradle-to-cradle method…

* Or 30,000 hours: at 10 hours per day, every day, this equals a minimum of 10 years, or more if it is used less and the heat is properly dispersed.