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Abstract: In this paper, the prospect of integrating a combined paper&pulp mill with fuel production via biomass gasification was investigated. In the study, three different types of gasifiers (circulating fluidised bed, entrained flow and indirect gasification) and three fuel processes (dimethyl ether, methanol and Fischer-Tropsch wax synthesis) were investigated using computer simulations. The paper reports differences from the stand-alone cases and the integrated cases, using the electricity equivalence efficiency as a measure. Only 6 out of the 18 integrated cases studied displayed a positive result from integration and no obvious fuel selection that stand out as the most beneficial one, however the synthesis of dimethyl ether is, in combination with all gasifiers assessed a rather good choice, with an change in efficiency from integration ranging from −1% to 4%. Dimethyl ether is not the best choice if the electrical equivalence is to be maximised however. In this case the combination of circulating fluidised bed gasification and methanol synthesis should be pursued. The production of Fischer-Tropsch wax should according to the chosen measure not be produced; however there is an added value in the production of a non-oxygenated fuel which has not been taken into account in this particular study. All cases leads to a reduction of 0.4–0.9 kg CO2 per kg of dry biomass used in the process for fuel synthesis and the possibility to export bark is a more significant factor in this respect than which type of fuel is synthesised. [Copyright &y& Elsevier]

Abstract: In this work, we characterized Hesperaloe funifera; pulp and paper obtained by subjecting the plant raw material to soda, soda–anthraquinone, ethanolamine, ethyleneglycol and diethyleneglycol cooking. In addition, the solid fractions extracted by acidifying the cooking liquors, rich in lignin, were used to obtain synthesis and fuel gases. The contents in lignin, α-cellulose, holocellulose, hemicellulose, ethanol–benzene extractives, hot water solubles, 1% NaOH solubles and ash of H. funifera were found to be 7.3%, 40.9%, 76.5%, 35.6%, 4.0%, 13.5%, 29.5% and 5.9%, respectively. The mean fibre length, 4.19 mm, exceeds those for some non-wood materials. Hesperaloe pulp obtained by cooking with 10% NaOH and 1% anthraquinone at 155 °C for 30 min exhibited good values of yield (48.3%), viscosity (737 mL g−1), Kappa number (15.2), tensile index (83.6 Nm g−1), stretch (3.8%), burst index (7.34 kN g−1) and tear index (3.20 mNm2 g−1). Acidification to pH 6 of the liquor resulting from the soda pulping of 500 g of plant raw material provided an amount of 13.90 g of lignin-rich solids pyrolysis of which gave a gas mixture containing 1.13% H2, 31.79% CO and 1.86% CH4 by weight. Gasification of the same sample provided a mixture containing 0.18% H2, 24.50% CO and 17.75% CH4, also by weight. [ABSTRACT FROM AUTHOR]