1 Dipartimento di Ingegneria Civile, dell'Energia, dell'Ambiente e dei Materiali, Università degli Studi Mediterranea di Reggio Calabria, Italy.
2 Department of Chemical, Biological and Environmental Engineering, Universitat Autònoma de Barcelona, Spain.
Waste Manag Res. 2018 Jan;36(1):17-29. doi: 10.1177/0734242X17741193. Epub 2017 Nov 14.
Opuntia ficus-indica (OFI) is an emerging biomass that has the potential to be used as substrate in anaerobic digestion. The goal of this work was to investigate the effect of three pretreatment techniques (thermal, alkaline, acidic) on the chemical composition and the methane yield of OFI biomass. A composite experimental design with three factors and two to three levels was implemented, and regression modelling was employed using a total of 10 biochemical methane potential (BMP) tests. The measured methane yields ranged from 289 to 604 NmL/gVS; according to the results, only the acidic pretreatment (HCl) was found to significantly increase methane generation. However, as the experimental values were quite high with regards to the theoretical methane yield of the substrate, this effect still needs to be confirmed via further research. The alkaline pretreatment (NaOH) did not noticeably affect methane yields (an average reduction of 8% was recorded), despite the fact that it did significantly reduce the lignin content. Thermal pretreatment had no effect on the methane yields or the chemical composition. Scanning electron microscopy images revealed changes in the chemical structure after the addition of NaOH and HCl. Modelling of the cumulated methane production by the Gompertz modified equation was successful and aided in understanding kinetic advantages linked to some of the pretreatments. For example, the alkaline treatment (at the 20% dosage) at room temperature resulted to a μ (maximum specific methane production rate [NmLCH/(gVS·d)]) equal to 36.3 against 18.6 for the control.
仙人掌（Opuntia ficus-indica，OFI）是一种新兴的生物质资源，具有作为厌氧消化底物的潜力。本研究旨在探讨三种预处理技术（热、碱、酸）对仙人掌生物质的化学组成和甲烷产量的影响。采用三因素两到三水平的复合实验设计，并利用总共 10 次生物化学甲烷潜能（BMP）测试进行回归建模。测量的甲烷产量范围为 289 至 604 NmL/gVS；结果表明，只有酸性预处理（HCl）显著提高了甲烷生成量。然而，由于实验值相对于底物的理论甲烷产量相当高，因此仍需要通过进一步研究来证实这种效果。碱性预处理（NaOH）虽然显著降低了木质素含量，但对甲烷产量没有明显影响（平均减少了 8%）。热预处理对甲烷产量和化学组成没有影响。扫描电子显微镜图像显示，NaOH 和 HCl 处理后化学结构发生了变化。通过 Gompertz 修正方程对累积甲烷生成量进行建模取得了成功，并有助于理解与某些预处理相关的动力学优势。例如，在室温下用 20%剂量的碱处理，最大比甲烷生成速率（NmLCH/（gVS·d））达到 36.3，而对照为 18.6。
