Kozłowski Michał, Papaj Bernard, Sobieraj Karolina, Świechowski Kacper, Kosiorowska Katarzyna, Białowiec Andrzej
Department of Applied Bioeconomy, Wroclaw University of Environmental and Life Sciences, 51-630, Wroclaw, Poland.
Sci Rep. 2025 May 28;15(1):18728. doi: 10.1038/s41598-025-02564-0.
Anaerobic digestion (AD) is a useful process that could be utilized for food waste (FW) management. Previous studies have shown that carbon materials (CMs) could be an important additive for increasing biomethane yield. However, why CMs improve AD is still uncertain. A significant body of research has been dedicated to investigating the impact of CMs supplementation on biogas production. However, this article specifically emphasizes examining this effect concerning the specific surface area and the functional groups (e.g. hydroxyl groups, carbonyl groups, or unsaturated carbon structures) present on the surface of CMs, produced by torrefaction-TP (240 °C/60 min), pyrolysis-BC (600 °C/60 min), and hydrothermal carbonization-HC (240 °C/60 min/6-10 Bar) processes. The analyses showed that the size of the specific surface area of the CMs (TP-7.72 m g, BC- 115.00 m g, HC-5.46 m g), does not correspond to the production of biomethane. The highest biomethane potential was found for CMs with the lowest SSA, precisely TP and HC, equal to 407 and 394 mL gVS, which was about 13 and 9% higher than production from FW as a sole source of carbon, respectively. The FTIR analysis confirmed the abundance of different organic functional groups on the surface of TP and HC, which could contribute to improved AD performance. These organic residuals, as thermal degradation products, could be an additional source of carbon for microorganisms. The addition of BC, with the highest SSA, decreased the first-order biomethane rate constant k by 16.4% in comparison to food waste without CMs, which could be related to the presence of harmful, more complex organic compounds on the surface of biochar.
厌氧消化（AD）是一种可用于食物垃圾（FW）管理的有用工艺。先前的研究表明，碳材料（CMs）可能是提高生物甲烷产量的重要添加剂。然而，CMs为何能改善厌氧消化仍不确定。大量研究致力于调查添加CMs对沼气生产的影响。然而，本文特别强调研究这种影响与CMs表面的比表面积和官能团（如羟基、羰基或不饱和碳结构）的关系，这些CMs是通过烘焙-TP（240°C/60分钟）、热解-BC（600°C/60分钟）和水热碳化-HC（240°C/60分钟/6-10巴）工艺制备的。分析表明，CMs的比表面积大小（TP-7.72 m²/g，BC-115.00 m²/g，HC-5.46 m²/g）与生物甲烷的产量并不对应。比表面积最低的CMs，即TP和HC，生物甲烷潜力最高，分别为407和394 mL/gVS，分别比仅以FW作为碳源的产量高出约13%和9%。傅里叶变换红外光谱（FTIR）分析证实了TP和HC表面存在大量不同的有机官能团，这可能有助于提高厌氧消化性能。这些作为热降解产物的有机残余物可能是微生物的额外碳源。与不添加CMs的食物垃圾相比，添加比表面积最高的BC使一级生物甲烷速率常数k降低了16.4%，这可能与生物炭表面存在有害的、更复杂的有机化合物有关。
