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International audience; The main objective of this research is to investigate the combustion and emission characteristics of syngas by using an atmospherics flame burner. The syngas produced by gasification of olive waste particles in a small pilot scale 5 kWth downdraft fixed bed gasifier, where the oxidizing agent is a air, was combusted in a combustor through a burner. The gasifier has an inner diameter of 0.190 m lined with refractory cement and a height of 0.682 m. The throat diameter is 0.047 m. The gasifier are burner are made of stainless steel. The nozzle exit inner burner diameter is 25 mm. The fuel nozzle consists of a center body fuel injector, a radial air swirler, and a mixing area. Thermocouples type-K were used for recording temperature profiles at different parts of the gasifier and at different sections of air/syngas flame. Air flow at the inlet of the gasifier is regulated via mass flow controller while the syngas is regulated by high temperature vortex flow meter. For syngas and exhaust analysis, gas chromatograph and exhaust gas analyzer were used, respectively. Syngas combustion emissions measured include NO, CO, O2 and CO2. In this work, we compared the performance of olive waste and wood pellet as fuels for downdraft gasification to reveals the influences of the operating parameters such as reactor temperature and equivalence ratio on the hydrogen rich-syngas composition. The composition of syngas and gasification performance for olive waste and wood pellet were analyzed comparatively. Physicochemical characterization were checked through ultimate and proximate analyses as well as energy content measurement. Ultimate analysis was carried out to determine carbon (C), hydrogen (H), oxygen (O), nitrogen (N) and Sulphur (S) weight fractions. Proximate analysis was done using a thermogravimetric analyzer (DTG-60). A calorimetric bomb (Parr 2100) was used to measure the high heating value (HHV). The purpose of the present work is to report results on syngas compositions (H2, CO, CO2, CH4, N2) and CO/H2 molar ratio effect on air/syngas flame structures and combustion emissions.

International audience;  Study of non-premixed turbulent flames stabilized by a swirler Control of pollutant emissions / emissions standards Improve performances of combustion plants Investigations on flame characteristics Effects of oxygen enrichment Effects of steam and CO2 dilution Effects of swirl intensity

International audience; Development of modular adapted energy concept- Gasifier - multi-fuel burner - boilerCharacterization of syngas and biogas flames - Experimentally: stability, pollutant emissions, temperature - Numerically: Calculations of laminar burning velocity, flame temperature, pollutants (NOx, CO)…This poster: some results of calculations

International audience; Optimization of industrial boilers by the combination of combustion air enriched with oxygen and reducing CO2 by a membrane capture. Development of a CO2 capture pilot unit dedicated to district heating heat production units and validate it on an industrial site.

International audience; The study is motivated by CO2 capture applications further to the increase of CO2 concentration by the O2 enrichement. Objective- Optimization of industrial boilers by the combination of combustion air enriched with oxygen and reducing CO2 by a membrane capture.- Study the characteristics of turbulent CH4-air flames with O2 enrichment : Flame stability, Pollutant emissions (CO, NOx, CO2), Velocity field

International audience; CO 2 emissions remain the main greenhouse gas reduction targets in the industrial sector for the EU. The CO 2-Energicapt project aims to demonstrate the feasibility of CO 2 capture by coupling CO 2 capture technologies and oxygen enrichment systems. A pilot plant on a small scale is built to demonstrate the efficiency of a membrane based CO 2 capture technology integrated to an existing District Heating Plant in the Paris region. This presentation focuses on the combustion part of the CO2-Energicapt project involving a specific burner technology, operating in partially premixed mode, well suited for oxygen-enhanced combustion. The combustion characteristics of methane oxygen-enriched air turbulent non-premixed swirling flames are presented. The main results concern the flame stability maps, NO x , CO 2 and CO emissions, and flame dynamics for different oxygen addition rates. The exhaust gas compositions are measured using gas analysers. Stereoscopic Particle Image Velocimetry (Stereo PIV) is used to analyse the dynamics of swirling flows in non-reacting and reacting conditions. The measurements are performed for oxygen concentrations ranging from 21 % to 30 % by volume, with swirl numbers from 0.8 to 1.4 and global equivalence ratios from 0.8 to 1. The Stereo PIV results (Fig.1) in the center plane and the transverse plane of the swirling jet illustrate the interactions between flame and large-scale vortices. Swirling rates, as well as the entrainment rates, are also quantified based on measured velocity distributions close to the burner exit in non-reacting and reacting conditions. The results show various flame types from purely diffusion flames (Fig.1b) to partially premixed ones depending on the fuel and oxidizer flow rates. Increasing the swirl number and the oxygen addition rate significantly improve the flame stability. The results demonstrate that the CO 2 emissions in the exhaust gases linearly increase with increasing O 2 content in the oxidizer. The CO emissions are shown to decay exponentially, whereas the NO x emissions, mainly produced through the thermal pathway, increase strongly with oxygen enrichment. Work is continuing to optimise the emissions namely to reduce NO x emissions. Fig.1 Field of axial velocity U (a) (S n = 0.8 and Ф = 0.8) and flame images (b,c,d,e,f).