Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials, School of Environment and Energy, Peking University Shenzhen Graduate School, Nanshan District, Shenzhen 518055, PR China.
Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials, School of Environment and Energy, Peking University Shenzhen Graduate School, Nanshan District, Shenzhen 518055, PR China.
J Hazard Mater. 2023 Oct 5;459:132221. doi: 10.1016/j.jhazmat.2023.132221. Epub 2023 Aug 4.
Hydrothermal liquid digestate has been widely accepted as a substrate in anaerobic digestion (AD) for energy recovery. However, the potential negative impacts of hydrothermal liquid digestate on AD remain unclear. In this study, the organic biodegradability of hydrothermal liquid digestate produced from hydrothermal treatment (HTT) at different temperatures was analyzed, and the formation and degradation process of potential inhibitory substances were discussed. Results demonstrated that the AD lag phase of hydrothermal liquid digestate increased from 3 days at raw liquid digestate to 5-21 days. When the HTT temperature reached 220 °C, the methane yield decreased by 48%, and more than 71% of the organics in the hydrothermal liquid digestate were not utilized by AD. Biorefractory substances, such as fulvic and humic acids, accumulate in the hydrothermal liquid digestate. Potential inhibitory substances from Maillard reactions mainly affect the methanogenesis of AD. Most inhibitory substances were degraded within 7-22 days, with the degradation rate following the order of pyrroles > pyrazines > ketones > imidazoles > indoles. The AD community structure and methane conversion were partially re-established after most inhibitory substances were degraded. This study provides valuable information on eliminating the potential negative effects of hydrothermal liquid digestate on AD.
水热液体消化液已被广泛接受作为厌氧消化（AD）的底物，以回收能源。然而，水热液体消化液对 AD 的潜在负面影响尚不清楚。本研究分析了不同温度下水热处理（HTT）产生的水热液体消化液的有机生物降解性，并讨论了潜在抑制物质的形成和降解过程。结果表明，水热液体消化液的 AD 迟滞期从原料液体消化液的 3 天增加到 5-21 天。当 HTT 温度达到 220°C 时，甲烷产率下降了 48%，超过 71%的水热液体消化液中的有机物未被 AD 利用。富里酸和腐殖酸等生物难降解物质在水热液体消化液中积累。美拉德反应产生的潜在抑制物质主要影响 AD 的产甲烷作用。大多数抑制物质在 7-22 天内降解，降解速率的顺序为吡咯＞吡嗪＞酮＞咪唑＞吲哚。大多数抑制物质降解后，AD 群落结构和甲烷转化率部分得到重建。本研究为消除水热液体消化液对 AD 的潜在负面影响提供了有价值的信息。
