Integration of white rot mushroom cultivation to enhance biogas production from oil palm kernel pulp by solid-state digestion

Solid-state fermentation is one of the promising technologies for biogas production because of its low water footprint and solid output which is potentially used in fuel or agricultural applications. Oil palm kernel pulp (OPKP) is a by-product generated from the extraction of palm kernel oil from the mesocarp of the oil palm tree and usually contains a large amount of lignocellulose and moderate protein content, which makes it suitable for use as a mushroom substrate. Cultivation of white rot mushrooms on lignocellulose may enhance its biodegradation by biodelignification. In this study, the incorporation of the cultivation of edible white rot mushrooms, Pluerotus ostreatus and Pleurotus pulmonarius, to enhance biogas production by solid-state digestion was studied. The biological efficiency of mushroom production from the OPKP substrate of P. ostreatus and P. pulmonarius was 49.81% ± 11.28% and 46.94% ± 13.49%, respectively, corresponding to the substrate weight loss of 15.87% and 13.92%. After 30 days, methane yield obtained through the solid-state digestion of P. ostreatus- and P. pulmonarius-treated OPKP substrates was increased to 98.11 mL/gVS (191%) and 101.10 mL/gVS (197%), respectively, compared with the untreated OPKP substrate. In consideration of energy loss during the biological conversion, the calorific values of the OPKP substrate, P. ostreatus-treated OPKP substrate, and P. pulmonarius-treated OPKP substrate were 11.03 ± 0.71 kJ/g, 9.30 ± 0.23 kJ/g, and 8.83 ± 0.70 kJ/g, respectively, while those of the digestion residues of P. ostreatus and P. pulmonarius-treated OPKP substrates were 8.45 ± 0.13 kJ/g and 8.55 ± 0.11 kJ/g, respectively

Elaboration d'hydrogels de chitine induite par non-solvant (relations procédé-produit)

Des hydrogels de chitine ont été préparés par gélification induite par pénétration de non solvant. Plusieurs procédés ont été étudiés (i) immersion dans un bain de non solvant pur (eau) (ii) immersion dans une solution binaire solvant (N-méthyl pyrrolidone) / non solvant (iii) un procédé original d'élaboration par exposition à des vapeurs de non solvant. Les gels élaborés par ces procédés ont été comparés en terme de morphologie selon une analyse multi-échelle (retrait surfacique, épaisseur, propriétés de relargage - coefficient de diffusion, module de Young apparent, SAXS, WAXS). Les différences observées ont été expliquées par l'influence des cinétiques de transfert en solvant et non solvant sur la structuration du gel au cours de l'élaboration. Une modélisation des transferts de matière au cours du procédé de gélification a été développée. Elle a permis de quantifier les cinétiques de pénétration de non solvant et d'évaporation du solvant et de simuler l'évolution des profils de concentration au cours du temps dans la solution de chitine pendant la gélification.Chitin hydrogels were prepared by using non solvent induced gelation process. Different processes have been studied (i) pure non solvent (water) bath immersion process (ii) binary solvent (N-methyl pyrrolidone) / non solvent bath immersion process (iii) a novel method to induce gelation using the exposure of chitin solution to non solvent vapour. The elaborated gels with these processes have been compared in term of morphology using a multi scale approach (area shrinkage, thickness, release properties diffusion coefficient, apparent Young's modulus, SAXS, WAXS).The influence of solvent and non solvent kinetics on the gel structure during elaboration process explained the difference observed between the gels. Mass transfer modelling during gelation process has been developed. It lead to the quantification of the non solvent penetration and solvent evaporation and to the simulation of the concentration profiles with time in chitin solutions during gelation.MONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF