Hot water extraction (HWE) removes hemicellulose from woody biomass to give improved end products while producing a sugar-rich by-product stream, which requires proper treatment before disposal. Hot water extracted Norway spruce (Picea abies) at two different pretreatment conditions (140 °C for 300 min (H140) and 170 °C for 90 min (H170)) generated hydrolysate as a by-product, which was used in mesophilic anaerobic digestion (AD) as substrate. H140 gave a higher methane yield (210 NmL/g COD—chemical oxygen demand) than H170 (148 NmL/g COD) despite having a lower concentration of sugars, suggesting that different levels of inhibitors (furans and soluble lignin) and recalcitrant compounds (soluble lignin) affected the methane yield significantly. Organic loads (OLs) had a negative effect on the methane yield, as observed during AD of H170, while such an effect was not observed in the case of H140. This suggests that the decrease in methane yield (32%) of H170 compared to H140 is primarily due to inhibitors, while the decrease in methane yield (19%) of H140 compared to the synthetic hydrolysate is primarily due to recalcitrant substances. Therefore, both OL and pretreatment conditions must be considered for efficient anaerobic digestion from hydrolysate for enhanced methane production.

中文翻译：

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水热预处理木质纤维素生物质（挪威云杉（Picea abies）的中温厌氧消化）

热水提取（HWE）可从木质生物质中去除半纤维素，从而改善最终产品，同时产生富含糖分的副产物流，在处理之前需要进行适当的处​​理。热水提取的挪威云杉（云杉））在两种不同的预处理条件下（140°C持续300分钟（H140）和170°C持续90分钟（H170））生成水解产物作为副产物，将其用作中温厌氧消化（AD）的底物。尽管糖浓度较低，但H140的甲烷产量（210 NmL / g COD-化学需氧量）比H170（148 NmL / g COD）高，这表明抑制剂（呋喃和可溶性木质素）和难降解化合物的含量不同（可溶性木质素）显着影响甲烷的收率。如在H170的AD期间所观察到的那样，有机物负载（OLs）对甲烷产率具有负面影响，而在H140的情况下则未观察到这种影响。这表明与H140相比，H170的甲烷收率降低（32％）的主要原因是抑制剂，与合成水解产物相比，H140的甲烷产率降低了19％，这主要归因于顽固性物质。因此，必须同时考虑OL和预处理条件，才能有效地从水解产物中进行厌氧消化，以提高甲烷的产量。