Frequently Asked Questions
What is a neglected?
This term includes some brownfields and industrial by-products which are a burden to society in the current regulatory and technological conditions.
Brownfields with low financial pressure and those subject to a ban on building (mine hazard, pollution) are a heavy burden to society, often complex to manage.
Industrial by-products, usually considered as waste, can lead to a loss of competitiveness for our local industries, forced to consider expensive solutions to evacuate and / or treated (incineration, landfills, etc.). .
One of the main objects of the research project is to find a way of valuing these neglected in the LORVER project.
What is soil construction?
The soil construction is an environmental technology which aims to ensure the rehabilitation of degraded soil by restoring to its agronomic properties to allow revegetation and recolonization of soil fauna. The process is subject to a joint patent Valterra / INRA / UL. Its originality lies in the use of industrial by-products and processed land, instead of vegetable soils to build a low cost fertile soil.
The materials are combined in different soil layers which are the subject of an optimized formulation , depending on the objectives or rehabilitation : |
- ecological restoration of the site,
- landscape integration which may include in a most important redevelopment project,
- non-food biomass production to improve the local land economic value. The soil profile is optimized for culture,
- water containment to prevent the pollutant transfer initially present on the sites.
Construction of ground
Constructed soil profile
Prairie on built ground
Why do we speak of biomass?
Biomass is the whole biological organic matter (carbon-containing). LORVER project is centered on vegetable biomass with the aim to valorise by transforming them into energy or in materials.
The industrial hemp cultivation is it emerging in France ?
The France in 1850 included approximately 176,000 ha of hemp cultivation in almost all regions. Its uses are many , from the clothing to the manufacture of ropes and sails for marine oil through lighting and stationery. This culture was then declined because the disappearance of the sailing ships , the advent of the exotic and synthetic fibers market, and the prohibition of culture in many Western countries. In the sixties , hemp had almost disappeared from our countryside, despite the lenient regulatory context in France.
Indeed, France has never prohibited hemp but framed production (varietal selection, etc.). The acquired skill today allows France to assert his experience to accompany the renewal of culture through new opportunities in areas as diverse as eco-construction, plastics, animal bedding, horticultural mulch, etc.
What are pyrolysis and gasification?
The wood pyrolysis corresponds to its thermal decomposition when heated between 250 and 500 ░C without oxygen. It produces coal gas (CO, CO2, H2, ...) and bio-oil.
During gasification, a small amount of oxygen is added in order to convert the maximum of bio-oils and coal into syngas (CO, H2, CO2, CH4, ...).
In the pyrolysis gasification process developed by SEA MARCONI for LOVER project, we want to produce syngas but also coal (biochar) which will be valorised respectively in heat / electricity and spreading for carbon storage, sequestration and fertilization of soil pollutants.
What is biochar? What are its valorisation possibility?
The biochar is a solid material produced by heating natural organic materials, in the absence of oxygen. This coal can thus be obtained from various renewable resources such as wood (which gives the charcoal that can be found in a barbecue) as well as agricultural residues, sludge from sewage and generally all types organic wastes. Biochar is very biodegradable and contains a lot of carbon: its burial in soil would therefore permanently store carbon from photosynthesis and thus fight against greenhouse gas emissions. Its presence in the soil may also provide other benefits, such as improved soil fertility for plant production but also reduced toxicity associated with the presence of pollutants. The exact definition of the benefits and limitations provided by the use of biochar in soils is therefore currently the subject of much research in the world.
What is a biocomposite material?
A composite material is a blend of immiscible components having strong adhesion ability. It has properties that the individual ingredients do not have. In a biocomposite, synthetic reinforcement (eg, fiberglass, carbon fiber) is replaced by vegetable fibers like hemp fibers or nettle fibers and petrochemical resinn (eg PVC, polyethylene ...) is replaced by plant-based resin (biobased polyester, resin based tannins etc.). In addition to their environmental interest related to their origin and their recyclability, biocomposites thanks to relatively low densities are innovative materials for the futur for automotive and aerospace industries.
What are trace metals?
The term "metal trace elements" tends to replace "heavy metals". Metals are present in trace amounts in soils for natural reasons (geochemical background) or as a result of industrial pollution, urban pollution etc.. There are, iron and its alloys, zinc, lead, cadmium, copper, chromium, nickel, titanium, uranium, etc.. Some of these metals at low concentrations are essential to life, they are called trace elements. While others are toxic. However toxicity often depends on the metal chemical form. The distribution of chemical forms is called speciation. It depends on pH, redox conditions, and more generally of the chemical and biological environment.
What is a hyperaccumulator plant?
Some plant species are able to accumulate strong and unusual metallic trace elements potentially phytotoxic (eg Cd, Co, Cu, Pb, Ni and Zn) from metalliferous soils. Such plants are called hyperaccumulators. To date, over 400 species of hyperaccumulating plants were listed by the world most of them (over 320 species) are known to hyperaccumulate Ni. In Europe, such endemic plants are found on rich metal natural sites, such as ultramafic sites rich in Ni, and old producing mines. They are mainly represented by species of the type Alyssum and Noccaea. An example, shown on pictures, is caerulescens Noccaea which can reach concentrations on aerial parts up to 40 000 mg Zn.kg-1 and 3000 mg Cd.kg-1.
Noccaea caerulescens, hyperaccumulator Zn-Cd, at different stages of development
What is phytomining?
The phytomining or phytomine aim is the valorisation of metals (or chemical elements) dispersed in some soils by by cultivating hyperaccumulating plants. Some natural or polluted soils contain relatively high concentrations of metals (nickel, cadmium, zinc, lead, etc..). However the levels are too low for these metals are considered minerals. The hyperaccumulating plants can extract these metals from soil and store them in their tissues. After harvest, we can use a pyrometallurgical or hydrometallurgical process to treat biomass and recover metal elements in a usable form (metal, metal salt etc..).
On the picture is presented the nickel example. Nickel is naturally present in natural soils, known as serpentine soils in concentrations between 1 and 7 g.kg-1. The Alyssum wall plant (left picture) accumulates more than 10 g of nickel per kg of dry biomass. Thus it is possible to produce biomass corresponding to 100 kg of nickel per hectare. A hydrometallurgical process was developed and patented to produce the double salt of nickel sulphate and ammonium hexahydrate (right picture), which is used in surface treatment.
What is an ecosystem service ?
Inside LORVER project, the objective of the establishment of new ecosystems are biomass production, reduction of soil and water pollution, biodiversity protection and carbon stockage against global warming, and some esthetic and recreative functions for residents.
What is a life cycle analysis? What will be its interest in the LORVER project?
The life cycle analysis (or LCA) is a environmental analysis tool. Governed principally by the ISO 14041-43 standards, it is to inventory the material flows (resources, products, waste , etc. . ) and energy throughout the life cycle of a product "from cradle to grave". This inventory provides the basis for assessing the environmental impact of the object studied .
Several indicators can be taken into account: the consumption of non-renewable resources, water and energy, human or environmental toxicity, the potential effect on the climate, eutrophication, etc.
These impacts are then compared with the services rendered by the object studied such as: insulating a wall with a performance and for a given period. LCA can thus allow to compare different techniques (such as hemp insulation wool and the polyurethane).
The objectives of the LCA and the services studied greatly influence the data necessary, the indicators taken into account, the level of technical results. It is therefore necessary to define the upstream inventory, and then verify that the objectives of the LCA have been achieved in terms of impact assessment.
Finally, a sensitivity analysis assesses the robustness of the results against measurement uncertainties , the variability of processes, how impacts have been attributed to a product rather than another , etc.
Inside LORVER project , LCA conduct is used to determine the environmental impacts, positive and negative, of each sector. Combined with economic and social data (resource costs, job creation, etc.), it will meet two main objectives:
- identify the ameliorations necessary to make each sector more sustainable: economically viable, job-creating, environmentally,
- assess the economic, social and environmental relevance of these sectors, relative to a baseline scenario (fallow land maintained in good condition, no enhancement of co-products, etc.).
The dedicated non-food crops, are they not questionable from an ethical and economic point of view?
Non-food crops are used to produce biofuels and biomaterials. These products are renowned renewable and help to slow the depletion of fossil resources.
Therefore face their development in the early 2000s and more specifically energy crops in the world, a polemic is born about the dangers with a competition between alimentary and non-food agriculture. Indeed, by reducing alimentary agricultural soils for non-food production, we are exposed to a decrease of alimentary production and therefore an increase of resource prices.
Non-food biomass produced with LORVER project does not fall into a competition because the new cultivation areas are unsuitable for alimentary agriculture : brownfields.