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Kraiem N.,CNRS Mulhouse Institute of Materials Science | Kraiem N.,University of Monastir | Kraiem N.,Laboratoire Gestion des Risques | Jeguirim M.,CNRS Mulhouse Institute of Materials Science | And 5 more authors.
Energy | Year: 2014

Mediterranean countries generate large amounts of olive oil byproducts mainly OMWW (olive mill wastewater) and EOSW (exhausted olive solid waste). Although solid residues have various valorization strategies, there is no economically viable solution for the OMWW disposal. This study aims to recover the OMWW organic contents through solid biofuels production. Hence sawdust and EOSW were used for the OMWW impregnation. The potential of the obtained samples, namely: IS (impregnated sawdust) and IEOSW (impregnated exhausted olive solid waste) were evaluated. Therefore, the physicochemical characterizations and thermogravimetric analyses of the samples were first performed. Secondly, the samples densification into pellets and their combustion in a domestic combustor were carried out. Combustion efficiencies, gaseous and PM (particulate matter) emissions as well as ash contents were evaluated. The analysis finding shows that addition of OMWW leads to an increase of energy content through the heating values increase. An increase of the impregnated samples reactivity was observed and assigned to the potassium catalytic effect. Combustion performances show that the OMWW addition has not a negative effect on their firing quality. Moreover, a beneficial effect on the pollutant emissions is observed with IEOSW pellets. The developed strategy constitutes a promising issue for the OMWW disposal and recovery. © 2014 Elsevier Ltd.

Elmay Y.,Laboratoire Gestion des Risques | Elmay Y.,CNRS Mulhouse Institute of Materials Science | Elmay Y.,University of Monastir | Jeguirim M.,CNRS Mulhouse Institute of Materials Science | And 3 more authors.
Renewable Energy | Year: 2014

Combustion tests of five date palm Tunisian residues, namely: Date Palm Leaflets (DPL), Date Palm Rachis (DPR), Date Palm Trunk (DPT), Date Stones (DS) and Fruit-stalk Prunings (FP), were performed in a laboratory scale furnace. Gaseous emissions such as CO2, CO, VOC, NOx and SO2, were analysed at 600°C under 30-60 NL/h flow rate. Obtained results were compared with sawdust combustion behaviour in order to select the most convenient biofuel for an application in domestic boiler installations.Combustion tests show that ignition delay and combustion time reaction are independent of the date palm residue. However, gaseous products emission rates and factors are correlated to the sample characteristics such as carbon, nitrogen and sulphur contents as well as fixed carbon and volatile matters contents. In order to optimize date palm residues combustion by decreasing unburnt gaseous emissions, special attention should be given to the design of the secondary air supply. © 2013 Elsevier Ltd.

El may Y.,Laboratoire Gestion des Risques | El may Y.,University of Monastir | Jeguirim M.,Laboratoire Gestion des Risques | Dorge S.,Laboratoire Gestion des Risques | And 2 more authors.
Energy | Year: 2012

Date palm residues are an attractive source of biomass energy since they are renewable, abundantly available and do not compete with food crops. Pyrolysis and combustion may be efficient methods of exploiting energy from these biomass resources. The purpose of this research was to investigate the thermal behavior of date palm biomass in order to evaluate their usefulness for energy production. In fact, ultimate and proximate analyses as well as thermal behavior of different date palm residues (date palm leaflets (DPL), date palm rachis (DPR), date palm trunk (DPT), date stones (DS) and fruitstalk prunings (FP)) were investigated. Non-isothermal thermogravimetric analyses (TGA) were performed to assess fuel reactivities under inert and oxidative atmospheres. Thermal degradation of all samples has exhibited quite similar behavior except DS. In contrast, different properties (e.g., reactivity, HHV or activation energy) were obtained, which may be attributed to a difference between tree parts composition (branches, trunk, fruit...). Thus, DPT and FP were found to be the most reactive materials in inert conditions; while in oxidative conditions, DPR is the highest one. In addition, activation energies corresponding to devolatilization regions under inert and oxidative conditions were 49.8, 45.2, 52.7, 50.9, 89.1 kJ mol -1 and 58.9, 49.6, 67.6, 57.7, 110.7 kJ mol -1 for DPL, DPR, DPT, DS and FP respectively. The obtained data, sample properties along with thermal behavior under inert and oxidative atmospheres as well as kinetic parameters, allowed the comparison of the obtained results with other biofuels and can be useful for the design of processing system for energy productions. © 2012 Elsevier Ltd.

Jeguirim M.,Laboratoire Gestion des Risques | Chouchene A.,Laboratoire Gestion des Risques | Reguillon A.F.,French National Conservatory of Arts and Crafts | Trouve G.,Laboratoire Gestion des Risques | Le Buzit G.,French National Conservatory of Arts and Crafts
Resources, Conservation and Recycling | Year: 2012

The disposal of olive mill wastewater (OMWW) by-product is one of the principal environmental problems of the olive oil industry. Therefore, several treatments have been proposed to reduce their environmental impacts; however, the high cost and the antibacterial effect of polyphenols are limiting factors for the different processes. A new valorisation strategy of OMWW based on absorption on sawdust followed by combustion has been studied. Two OMWW/sawdust blends, named impregnated samples (IS) with different mass ratios of OMWW in the mixture were prepared. In order to study the thermal behaviour of IS samples, combustion experiments were performed in a fixed bed reactor under isothermal conditions in a temperature range of 500-700 °C. In order to estimate the efficiency of the thermal process, emission factors of carbon oxides and oxygen consumption were measured. The thermal behaviours of IS were compared with that of the original sawdust under the same experimental conditions. © 2011 Elsevier B.V. All rights reserved.

Jeguirim M.,Laboratoire Gestion des Risques | Dorge S.,Laboratoire Gestion des Risques | Trouve G.,Laboratoire Gestion des Risques
Bioresource Technology | Year: 2010

The aim of this work was to study the thermal behavior of two herbaceous crops (Miscanthus giganthus, Arundo donax) obtained from energy plantations. Thermogravimetric analyses were performed at 5 °C min-1 under air atmosphere. The thermal degradation rates in devolatilization and combustion steps, the initial degradation temperature, and the residual weight were determined. The gas emissions and Particle Matter (PM) were also quantified. The thermal behavior of energy crops depends on the chemical composition. In fact, the initial degradation temperature for A. donax under air atmosphere was lower than for M. giganthus. However, the thermal degradation rate was higher for M. giganthus. Kinetic expressions for the degradation rate in devolatilization and combustion steps have been obtained for both energy crops. The comparison of the gas and PM emissions showed the same order of magnitude for both energy crops. In fact, 26.8 mmol/g of CO, CO2, VOC and 1.8 × 1013 particles/g were mainly emitted. © 2009 Elsevier Ltd. All rights reserved.

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