Syngas production by gasification of citrus residues

The exploitation of agro-industrial residues for syngas production through gasification process has attracted many interests in the sustainable energy for future developments in order to reduce the dependence from fossil fuels. Fruits processing industries generate important amount of residues, which must be managed properly by recycling, incineration or land filling. Particular attention has been recently addressed toward the use of residual biomass and wastes as sources for syngas production by thermo-chemical processes for heat and power production. In this context, thermo-gravimetric measurements of citrus residues (under nitrogen and steam atmosphere) allowed the selection of suitable gasification conditions (T>=720°C; S/B>=1.5 wt/wt). Therefore, steam gasification process of citrus waste was investigated from thermodynamic and experimental point of view. Experiments were carried out in a lab-scale reactor in presence of different catalytic materials (Ni/Al2O3, MgO and dolomite mineral). Results highlighted the effects of catalysts on outlet gas stream compositions mainly in terms of hydrogen content. In particular, gasification tests performed with dolomite get an H2 selectivity of about 84 vol%. Experimental results were also compared to thermodynamic data by process simulator software (Aspen Plus).