Fast pyrolysis and steam gasification of pellets prepared from olive oil mill residues

Abstract

Fast pyrolysis and steam gasification of pellets prepared from olive oil mill residues. Energy, Elsevier, 2018, 150, pp.a b s t r a c t This paper examines the fast pyrolysis coupled with the steam gasification of agropellets prepared from the olive oil industries by-products via Macro-thermogravimetry. Three pellets samples were prepared from exhausted olive mill solid waste, impregnated olive mill wastewater/exhausted olive mill solid waste and impregnated olive mill wastewater/pine sawdust. The behavior of the three pellets during the fast pyrolysis and the char gasification stages were generally comparable despite some small differences in the conversion rates or char yields. The gasification of impregnated olive mill wastewater/exhausted olive mill solid waste pellets was selected as a promising route for their valorization and the reduction of the pollution impacts of olive mill wastewater. The impregnated olive mill wastewater/exhausted olive mill solid waste pellets pyrolysis rate was affected significantly by the temperature in the range of 750 C e950 C. The mean char gasification rate was linearly dependent on temperature and steam molar fractions in the respective ranges of 750 Ce950 C and 10%e30% of steam concentration. The provided data on the fast pyrolysis and char gasification of the formulated impregnated olive mill wastewater/ exhausted olive mill solid waste pellets constitute new set of experimental data that can serve for the design of gasifiers working with such kind of wastes. (M. Jeguirim). t G ðsÞ 1080 ± 5 866 ± 5 755 ± 5 588 ± 5 598 ± 5 v G ð10 À3 s À1 Þ 0.93 ± 0.02 1.15 ± 0.02 1.33 ± 0.03 1.70 ± 0.03 1.67 ± 0.03

Hydrogen enriched syngas production via gasification of biofuels pellets/powders blended from olive mill solid wastes and pine sawdust under different water steam/nitrogen atmospheres

“…9 and confirmed in Table 3 (the characteristic time is approximately 4.92 10 À3 s À1 ), while the highest one is obtained by EOMSW-OMWW powder (approximately 9.80 10 À3 s À1 ). However, we notice that these values are higher than those reported in the literature under the same experimental conditions [39]. Indeed, in agreement with many published results in the literature, the blended and impregnated samples experience the highest gasification rates thanks to the mineral contents supplied by the OMWW as it is shown in Table 2 [4,11,26,32,39e41].…”

“…Note that under similar experimental conditions, Guizani et al [10] show that for a conversion (X) of 90%, and at a temperature of 900 C, the gasification rate of beech wood chips is approximately 15 10 À3 s À1 . However, our obtained values are lower than those found by Guizani et al [10], but higher than those reported by Lajili et al [39].…”

“…11 shows that the mean gasification rate increases from 4.80.10 À3 s À1 to 5.64.10 À3 s À1 at 800 C when we increase the steam molar fraction from 10% to 20%. However, according to Lajili et al [39], the average gasification rate is four times lower than what we find in this work, while the characteristic time of gasification is much higher (755 s at 850 C and 20% H 2 O for the pellets of impregnated exhausted olive mill solid waste). We can conclude that the powder form enhances the sample's gasification reactivity.…”

“…Moreover, we observe that for the powder form the highest rate of gasification is exhibited by EOMSW-OMWW (9.80 10 À3 s À1 ) with a characteristic time of 99 s followed by EOMSW100 (9.42 10 À3 s À1 ), PS-OMWW (7.89 10 À3 s À1 ) and PS100 (4.92 10 À3 s À1 ) respectively. Such behaviour can be attributed to the richness of the impregnated samples in inorganic matter provided by the OMWW, and especially in potassium (K) which is known by its high catalytic effect [4,39]. Indeed, the Schmidt's team, when working on the effects of biomass inorganics using rhodium as catalyst, concluded that the role of the sodium and potassium, which are the main inorganic compounds in our case, was to decrease the methane conversion by 9% and 16% respectively.…”

Bio-oil and Fuel Gas Production from Agricultural Waste via Pyrolysis: A Comparative Study of Oil Palm Empty Fruit Bunches (OPEFB) and Rice Husk

“…Complete combustion of a fuel occurs if there is sufficient oxygen supply. However, this process is not economically friendly due to the low efficiency of the combustion process and high production of emissions in particles and gas form [12]. Biomass pyrolysis is one of the most efficient technologies to produce biofuels.…”