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Le principal atout des biocarburants de seconde génération tient au fait que leurs procédés d"obtention doivent permettre de convertir l'intégralité de la biomasse. La compétition entre usage alimentaire et non alimentaire des produits agricoles est limitée. La plante complète est valorisée ; à terme, une valorisation de nombreux résidus et déchets organiques peut même être envisagée y compris pour la synthèse de nombreux produits chimiques et de molécules plateformes, précurseur de nombreuses applications chimiques.

The present paper gives an ovClView ofthe main outcomes ofthe non.technical task WP3D ofThermalNet, dealing with Environment, health and safety (EHS). The scope is to contrihute"to a better understanding and rapid consideration at the inception ofprojects about EHS issues, which will permit more suceessful and more rapid implementation ofbiomass technology. In addition to a stat'l of the ait review, realised and updated on a continuous basis, the results of specifie actions which have been undertillcen, are presented. The environment and emissions regulations within ail 25 EU member states have been collected and reviewed; a general framework ofa risk assessment mej:hodology has been elaborated with a plant case study for HSE issues assessment in gasifieation; pyrolysis bio-oils biodegradabitity has been assessed.

Le principal atout des biocarburants de seconde génération tient au fait que leurs procédés d'obtention doivent permettre de convertir l'intégralité de la biomasse. La compétition entre usage alimentaire et non alimentaire des produits agricoles est limitée. La plante complète est valorisée ; à terme, une valorisation de nombreux résidus et déchets organiques peut même être envisagée.

La région Languedoc-Roussillon bénéficie d'un des meilleurs gisements d'énergies renouvelables (EnR) de France, en particulier, en ce qui concerne l'énergie éolienne et l'énergie solaire. Elle est la seule région française qui développe des recherches relatives au solaire concentré et possède des installations de grande taille dans ce domaine. Un des trois pôles de compétitivité français relatifs aux EnR est basé en région (DERBI à Perpignan). Des technologies relatives aux EnR sont actuellement disponibles et matures (chaleur moyenne et basse température, photovoltaïque [PV], éolien) et devraient être développées très activement. Les points de vigilance concernent: l'acceptation des parcs éoliens, la concurrence sur l'utilisation de l'eau dans le cas du développement des agrocarburants. Les propositions d'actions sont: utiliser le pôle de compétitivité DERBI pour favoriser le développement des activités technologiques et économiques dans le domaine des EnR, promouvoir encore plus les EnR et les économies d'énergie dans l'habitat (pas seulement de l'eau chaude sanitaire), en particulier l'habitat à faible consommation et la climatisation solaire, renforcer la position unique de la région dans le domaine de la RDT sur le solaire concentré, encourager les recherches relatives au PV innovant, au stockage (électrochimique et thermique) à la production de combustibles alternatifs (hydrogène) et la gestion intelligente de l'énergie.

Si la biomasse (cultures annuelles et autres plantes, bois, résidus...) pour la production d'énergie (carburants liquides, solides ou gazeux, électricité) représente une part relativement faible, de l'approvisionnement énergétique des pays de l'OCDE, son rôle est loin d'être négligeable dans la production d'énergie des FED et de certains pays émergents. Et plusieurs scénarios énergétiques à moyen et long terme envisagent un recours croissant et important à la biomasse. Or si l'on examine les scénarios réalisés ces trente dernières années, on observe que l'émergence de la biomasse-énergie, toujours anticipée à horizon de moyen terme, n'a pas eu lieu. D'où la question du réalisme des scénarios élaborés aujourd'hui et des déclarations politiques attenantes lorsqu'ils confèrent une place significative à la biomasse-énergie dans un futur relativement proche. La biomasse-énergie est-elle simplement évoquée pour pouvoir présenter des scénarios énergétiques rassurants parce qu'annonçant une moindre dépendance vis-à-vis du pétrole et d'autres ressources épuisables ou porteuses de risques globaux majeurs (effet de serre, nucléaire...) ? Où recèle-t-elle de véritables potentiels ? Dans ce cas, quelles conditions doivent être réunies pour que ces potentiels soient exploitables durablement, des points de vue économiques, sociaux et environnementaux ? Les réponses manquent à ces questions ou pèchent par leur caractère partiel voire partial, ce qui peut contribuer à expliquer les décalages observés entre les scénarios passés et les réalisations. Il n'est en effet pas simple de se prononcer sur l'avenir d'une option qui dépend à la fois de choix énergétiques, d'usages des sols et de gestion des ressources et de l'environnement. D'autant moins que les décisions prises dans un secteur affectent les autres secteurs sans qu'il en soit tenu compte au sein d'une analyse d'ensemble. Même si les enjeux du rôle de l'agriculture et de la forêt dans la production d'énergie n'ont toujours pas été clarifiés, la recherche a pourtant avancé sur plusieurs thèmes centraux : technologies de valorisation énergétique de la biomasse ; évaluation agroéconomique de la disponibilité en biomasse ; prise en compte socio-économique de l'environnement... Il s'agit en particulier d'étudier si l'agriculture et les forêts seront en mesure, dans un avenir proche, de satisfaire une demande (très) importante en biomasse énergie sans entrer en compétition avec une demande croissante de matières premières (alimentaire et non alimentaire). Dans ce cas, les spécifications imposées par les filières de conversion, les contraintes de compétitivité économique vis à vis des produits pétroliers, et la prise en compte des enjeux environnementaux ne devraient ils pas amener à reconsidérer les pratiques et les politiques agricoles ? L'objet de cet article est de donner une vision des avancées en cours sur le thème de l'émergence de la biomasse-énergie avant de dégager les enjeux liés à ce développement : pour l'agriculture et la forêt notamment dans les pays en milieu tropical qui pourraient être amenés à jouer un rôle majeur dans une " Bio-économie " et où l'énergie pourrait constituer l'un des leviers à la modernisation de leur agriculture.

This ongoing LIFTOFF project intends to provide a solution to the problem of local energy demands in agricultural areas by utilizing local bio-fuels, like woodchips and agricultural residues in small and medium size CHP units. In order to achieve this goal, a multi-fuelled fixed bed gasification process with patented dry gas cleaning technology will be scaled up from large laboratory scale (400 kWth) where the process has been previously proven to a 1.5 MWth industrial demo plant. In order to ensure a successful outcome, the up scaling and the component integration need dedicated research and development activities that will be undertaken as part of this project together with the demonstration of the fully developed concept. The research activities also include development of models and tools, which focus on the design of the new LIFTOFF demo plant for woodchips.Three major outcomes are expected. The first one concerns the development and the design of the LIFTOFF principle on wood. The second is the construction and the building of the Danish wood fired CHP. And finally, the complete monitoring of the combined heat and power plant with a detailed feasibility for a second generation to be implemented potentially in Greece on agri-based residues will be carried out.

Pyrolysis is one of the three main thermo-chemical routes to convert biomass into useful primary energy products. Fast pyrolysis has benefited from active research programmes since the 1980's in order to obtain bio-oils, which can be used in engines for the generation of electricity or after refining in transport. Today, several demonstration plants are operating in Europe and North America where significant quantities of bio-oils are produced for research and development purposes and several commercial plants are at an advanced stage of planning. Thus, for a commercial development the question of safety procedures for human health and environment preservation is raised. The aim of this ongoing European Project (Biotox) is to comprehensively assess toxicity and eco-toxicity of a representative bio-oil after preliminary screening of a wide range of bio-oils from different processes and temperatures in order to: - identify the best operating conditions avoiding or minimising the formation of toxic products from the composition of the bio-oils, - produce a comprehensive and definitive MSDS with the proper preventive and remedial procedures to adopt during production, transport and use of bio-oils, - produce fast pyrolysis bio-oils with low impact on human health and environment by avoiding bio-oils production presenting potential toxic characteristics. In the project, the relation between process parameters on one hand and chemical composition and toxicity for human health and environment on the other hand will be investigated so as to recommend the operating conditions to produce bio-oils with the lowest impacts. Then, the optimised compositions of bio-oils will be submitted to the mandatory tests required by the EU legal authority, the objective being the definition of secure handling and storage procedures, in order to control the risks related to the product for the population and the environment. The effects of different types of exposure (inhalation, ingestion or skin contact) will be quantified, as well as the effects of long-term exposures. The impacts on the environment will also be evaluated for biodegradability and effects on bio-organisms. A MSDS safety procedure and guidelines for bio-oils use and transport will be published in order to allow oil producers to legally market and transport on the European market. Bio-oils have been produced from different reactors (fluid bed, rotating cone, circulating fluid bed, ablative pyrolysis, vacuum pyrolysis), under different temperature conditions (450 to 600°C), and from different biomass (forest residue, wood chips, beech...) in order to relate these parameters to oil composition, toxicological characteristics and biodegradability. (Texte intégral)

L'application traditionnelle de la gazéification concernait jusqu'à présent la production de gaz de synthèse, comme étape intermédiaire à la production d'ammoniac et d'engrais. La versatilité des cours du pétrole, l'ouverture du marché européen et international de l'électricité et le renforcement des contraintes environnementales ont ouvert de nouvelles possibilités à la gazéification et notamment la gazéification de la biomasse.

The main objective of the project was to develop an innovative highly efficient three stage slagging gasifier for combined heat and power production in the range of 1 to 5MWe. The new technology integrates a high temperature chamber where pyrolysis gases are cracked and ashes slagged. The new design allows to convert low quality fuel with high ash content. Activities were related to specific task in relation to technology development: - development and testing a new vibrofluidized bed pyrolysis reactor constituting the first step of the gasifier as pre conditioning of the gasifier as pre conditioning of the raw biomass, - development and testing a new high temperature reaction chamber feed with the pyrolysis gas for cracking and the carbon rich ash from the gasification reaction. This reactor works at high temperature to allow appropriate tar cracking and to cause melting of the ashes with complete utilisation of the carbon. It will result in a tar free gas. - build and test a char reduction chamber where char from the pyrolysis unit is converted into gas by means of steam gasification, - build and test a 50 kg/h unit and assess the feasibility of such technology. The results of the work carried out show that the integrated plant envisaged in the original proposal is technically feasible with more complex solutions that expected.

Utilisation of biomass and waste is a sustainable and environmentally friendly way of energy production, which may contribute to the reduction of the greenhouse effect, utilise local resources and improve local employment. Small CHP plants will certainly constitute the most promising route, as they represent the major market perspective in terms of replication. Gasification is the most promising technology if the technical constraints to its spreading, cleaning of the producer gas, is solved. The overall objective of this European project "Biomass Gasification for CHP with Dry Gas Cleaning and Regenerative Heat Recovery" is to develop, integrate and prove a dry gas cleaning system on an existing biomass gasification combined heat and power plant (250 kWth). The innovative idea of this project is a newly developed dry gas cleaning and heat recovery system. The dry gas-cleaning concept produces no wastewater and intends to solve and eliminate the tar problems associated with operation of biomass gasifiers by recirculating the tars back into the gasifier. The project includes the construction and test of the new gas-cleaning unit with an existing CHP gasifier for at least 500 hours. A study is carried out on the behaviour of tar under varying reactor and cooling conditions, and calculation of economical and environmental impact of the process will be realised in order to clarify whether the new gas treatment device used in small CHP gasification unit will be beneficial to replace conventional plants.

Charcoals were prepared without activation. The study of carbonization parameters influence have been investigated in order to determine the optimum conditions and to expand the adsorption properties of the charcoals. Pyrolysis tests have been done with optimum thermal parameters using firecrops, agricultural by-products or fallowing land growing. The optimum parameter the following : reactor heating rate of 3°C/mn, maximum temperature of 600°C and 5 h residence time at maximum temperature. The specific surface area and the standard adsorption tests have been applied to characterize the powdered charcoals. The none activated bio-adsorbent coals (NABAC) obtained from massive woods presents interesting adsorption properties : the specific surface area of NABAC from Eucalyptus wood exceed 3 70 m2/g. Since the aim of this project is both water treatment and energy generation, a method of energy recovery was carried out. This method consists of pollutant destruction via incineration of charcoals in a form of concentrated mixture of pulverulent solid dispersed within an aqueous foam (coal-water mixture).

Les pays tropicaux ont toujours été de gros utilisateurs de bioénergie. Les auteurs retracent ici, depuis 1970, au travers des recherches menées par le CTFT, puis le CIRAD-Forêt, les grandes étapes qui ont jalonné cette filière, en prenant en compte les réalités sociologiques des pays en développement

Ce rapport est une analyse critique du procédé de conversion de la biomasse CONVERTECH sur le système de l'hydrolyse. Le document fait le point sur les éléments positifs du procédé et sur ses limites

Tropical country economies are still based on agro-industries and wood industries. These industries generate a urge amount of waste which create damage to the environment when they are incinerated. In the same time conventional energies and technologies hardly cover their energy requirements. The rational use of these residues through biomass energy technology would be an appropriate solution. The scope of this work has consisted in the setting up of a simple decision making methodology adapted to tropical country economies. The economic framework of the Asean countries has been selected as case study. Figures show that agro- based industries offer a large potential of renewable energy sources. It has also enlighten that due to the economic growth of the region, the energy demand is skyrocketing with subsequent supply problems. Meanwhile, the different proven biomass energy technologies available are able to match with the energy requirement of the endusers and the technical constraints of the biofuel. Due to the number of technical options, decision makers are facing a choice problem. It consist in the selection of the best technology available between competing and alternative solutions. This choice constitute a real deadlock to biomass energy technology dissemination. Therefore, a decision making methodology tool adapted to tropical countries is proposed. Technical, micro-economic and also macro-economic criteria have been considered and a computer application developed. Seven technologies, for heat generation, power generation with or without cogeneration, using sugar cane residues, rice husk, wood wastes, palm oil residues in substitution to conventional technologies (coal, gas and petroleum products fired) are compared and ranked. Criteria considered are : cost/benefit ratio, environmental benefit vis a vis greenhouse gas emission impact (CO, C02, NOx, S02, COV and total C02 equivalent). Results have been validated through figures gathered from the demonstration projects supported by the European Union in Asean and will be discussed in the present paper.

The tropical countries economy is still mainly based on agriculture and the agro-industrial sector. Several of these countries are among the worldwide top ten in agriculture production such as rice, sugar cane, palm oil, coconut or processed wood exporting countries. All these agro and wood industries generate large quantities of residues. So far, the share of these residues used for heat or power generation is very limited, and when they are used, for self generation, the energy efficiency is very low, since their is no solvent demand for extra energy, and no incentives for private power generation. Some others, mainly wood industries are still runing diesel for their power production. A detailed investigation of electricity consumption in the world shows the level of tropical countries and particularly ASIA in a world wide scale. In a figure, plotting electricity consumption versus population, North America and Europe are at the top. Tropical countries are at the bottom. However, they have the greatest potential in increasing capacity rates and especially South East ASIAN countries which are enjoying among the largest economic growth rates in the world resulting in an ever increasing demand for energy. Modern and proven technologies for the processing and converting of biomass residues, combining efficiency and environment protection are available and could be increasingly used for private power generation in tropical countries. The objective of this paper is to draw up a picture of biomass resources available through agroindustries and wood industries and discuss the opportunities for private power generation considering the best technologies available. South East ASEAN region will be considered as a case study. Indeed, biomass contributes to about 20% of ASEAN industry primary energy demand and if fully utilized, the residues generated by the five sectors (rice, sugar, palmoil, coconut and wood) would represent almost 100% of conventional primary energy industry demand in the 1990.

Dans cet article sont présentées la composition et la toxicité des effluents de pyrolyse. Des résultats expérimentaux (études cinétiques, concentrations et facteurs d'émission des polluants) sont donnés pour différents procédés de pyrolyse (four pilote de laboratoire, four artisanal ou industriel). Les résutats montrent notamment comment le traitement thermique peut réduire considérablement les quantités de polluant émises tout en améliorant les rendements de production