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Parametric studies performed using Taguchi methods in order to optimize an experimental process and the results of the development of a laboratory vertical fixed-bed gasifier are reported. It was demonstrated that gasification is a reliable process on a laboratory scale and its results can be used at pilot plants. It was found that the frequency of sample injection at constant weight, the particle size of biomass, and the amount of secondary air have a greater effect on the formation of CO and H2 than that of the moisture content of the biomass and the process temperature.

Le présent travail consiste à étudier l'influence des caractéristiques des matériaux fibreux architecturés, tissus ou tricots, sur leur porosité aux échelles macro (motif du tricot ou du tissu) et microscopiques (fibres) et par conséquent sur les stratégies à adopter pour optimiser leur potentiel d'utilisation comme média filtrant. Les résultats obtenus portent sur des structures dont les paramètres ont été variés. Les résultats obtenus montrent que les tricots et les tissus présentent des différences au regard de leur efficacité de filtration et perméabilité à l'air. Par ailleurs, alors que la perméabilité à l'air évolue linéairement avec la porosité macroscopique des matériaux étudiés, l'efficacité de filtration suit une loi de puissance. Enfin, une pilosité de surface dense permet de générer une échelle de porosité microscopique et peut permettre d'augmenter l'efficacité de filtration sans diminuer la perméabilité à l'air., This work deals with the influence of the characteristics of architecturally structured fibrous materials, woven or knitted fabrics, on their porosity at the macro (knitted or woven fabric pattern) and microscopic (fibres) scales, and consequently with the strategies to be adopted to optimize their potential for use as filter media. The results obtained concern structures with various parameters. The results show that knitted fabrics and woven fabrics differ in their filtration efficiency and air permeability. Moreover, whereas the air permeability evolves linearly with the macroscopic porosity of the materials studied, the filtration efficiency follows a power law. Futhermore, dense surface pilosity allows the generation of a microscopic porosity scale and can increase the filtration efficiency without decreasing the air permeability.

PurposeBecause domestic heating appliances have the advantage of reducing emissions of greenhouse gas, their use is greatly increased and is largely recommended by European governments. However, some recent studies revealed that residential wood stoves and inserts are the source of many chemicals in the form of gases (CO2, CO, SO2, NOx), volatile organic compounds (alkane, alkenes, benzene, etc. …) and tars (mainly constituting poly‐aromatic hydrocarbons). The most important of them in terms of the emission factor and impact on environment and human health are carbon monoxide and fine particles. The aim of this study is to test the activity of a Pd‐based catalyst on the reduction of gas and particles during wood combustion in a domestic fireplace.Design/methodology/approachA catalytic system, placed at the exit of the fireplace, was developed to reduce pollutants. Pollutant characterization of a domestic fireplace from FONDIS SA, according to two paces of functioning (nominal and low‐charge), was performed with and without the presence of the catalyst. Fine and ultrafine particle distributions were characterized using an Electrical Low Pressure Impactor.FindingsThe presence of a catalyst drastically decreases the emission factors of CO. Though performing efficiently with respect to the total suspended particles emission factor, it does not significantly affect the emission factors of aerosols. Nevertheless, in the presence of the catalyst, air supply conditions slightly modify size distributions of PM0.1 to PM10.Practical implicationsA purification assembly, having catalysts for gases and combustion fumes from solid fuel heating apparatus, was patented and fireplaces are now commercially available from FONDIS SA.Originality/valueThis work was an adaptation of the catalytic system present in the automotive Diesel exhaust engines. It was not necessary to consult previous laboratory experiments in order to perform its activity because it was directly tested at the duct fireplace.