IRTA, GIRO-UPC Joint Unit, Torre Marimon, Road C59- km 12, E 08140 Caldes de Montbui, 08140 Barcelona, Spain.
Department of Engineering, Aarhus University, Blichers Allé 20, DK 8830 Tjele, Denmark; Faculty of Chemical Engineering, Universiti Teknologi Mara, 40450 Shah Alam, Malaysia.
Sci Total Environ. 2017 Oct 1;595:651-659. doi: 10.1016/j.scitotenv.2017.04.006.
Lignocellulosic biomasses such as wheat straw are widely used as a feedstock for biogas production. However, these biomasses are mainly composed of a compact fibre structure and therefore, it is recommended to treat them prior to its usage for biogas production in order to improve their bioavailability. The aim of this work is to evaluate, in terms of performance stability, methane yield and economic feasibility, two different scenarios: a mesophilic codigestion of wheat straw and animal manure with or without a low-energy demand alkaline pre-treatment (0.08ggof wheat straw, for 24h and at 25°C). Besides this, said pre-treatment was also analysed based on the improvement of the bioavailable carbohydrate content in the untreated versus the pre-treated wheat straw. The results pointed out that pre-treated wheat straw prompted a more stable performance (in terms of pH and alkalinity) and an improved methane yield (128% increment) of the mesophilic codigestion process, in comparison to the "untreated" scenario. The pre-treatment increased the content of cellulose, hemicellulose and other compounds (waxes, pectin, oil, etc.) in the liquid fraction, from 5% to 60%, from 11.5% to 39.1% TS and from 57% to 79% of the TS in the liquid fraction for the untreated and pre-treated wheat straws, respectively. Finally, the pre-treated scenario gained an energy surplus of a factor 13.5 and achieved a positive net benefit of 90.4€td, being a favourable case for an eventual scale-up of the combined process.
木质纤维素生物质，如麦秆，被广泛用作沼气生产的原料。然而，这些生物质主要由致密的纤维结构组成，因此，建议在用于沼气生产之前对其进行处理，以提高其生物利用度。本工作旨在从性能稳定性、甲烷产量和经济可行性方面评估两种不同的方案：麦秆和动物粪便的中温共消化，有无低能耗的碱性预处理（0.08ggof 麦秆，24 小时，25°C）。此外，还根据未处理和预处理麦秆中生物可利用碳水化合物含量的提高，对所述预处理进行了分析。结果表明，与“未处理”方案相比，预处理麦秆促使中温共消化过程具有更稳定的性能（pH 和碱度方面）和提高的甲烷产量（增加 128%）。预处理使液体部分中纤维素、半纤维素和其他化合物（蜡、果胶、油等）的含量从 5%增加到 60%，从 11.5%增加到 39.1%TS，从 57%增加到 79%TS，分别为未处理和预处理麦秆。最后，预处理方案的能源盈余增加了 13.5 倍，实现了 90.4 欧元的正净收益，这对于联合工艺的最终扩大规模是一个有利的情况。
