Costa Luís, Duarte M Salomé, Magalhães Carla Pereira, Pereira M Alcina, Cavaleiro Ana Júlia
CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga, Portugal.
LABBELS - Associate Laboratory, Braga/Guimarães, Portugal.
Appl Microbiol Biotechnol. 2025 May 30;109(1):131. doi: 10.1007/s00253-025-13519-w.
Anaerobic digestion (AD) is a well-established method for waste/wastewater treatment and biogas production, but challenges remain in improving its performance, particularly for toxic/inhibitory organic compounds such as lipids, hydrocarbons, polyphenols, pharmaceuticals, and other pollutants. Micro-aeration, which involves the controlled introduction of small amounts of oxygen, has emerged as a promising strategy to enhance microbial activity, stimulate the degradation of challenging compounds, and improve methane yields. This review addresses the different strategies used for effective oxygen dosing, measurement, and control, while also delving into the bioenergetics of the coexisting anaerobic and micro-aerobic pathways. Studies demonstrating the potential of micro-aeration to enhance the anaerobic treatment of recalcitrant organic pollutants, such as BTEX (benzene, toluene, ethylbenzene, and xylene) and pharmaceutical compounds, are reviewed. Several works use micro-aeration as a pretreatment, while those implementing it directly within bioreactors typically apply it intermittently. Nevertheless, in most cases, the application of micro-aeration is guided by a "trial-and-error" approach, and a systematic understanding of optimal strategies and dosing for different classes of pollutants remains lacking. The review also explores the diverse roles of micro-aeration in the AD of lipids, highlighting key microorganisms and underlying mechanisms that drive these processes, for instance, the role of facultative anaerobes in converting oleate into palmitate and protecting methanogenic communities. Finally, this work highlights future directions and remaining challenges in applying micro-aeration for the anaerobic treatment of organic pollutants. KEY POINTS: AD of lipids, hydrocarbons, dyes, pharmaceuticals, and other pollutants is challenging. Micro-aeration reshapes microbial communities and enhances pollutant degradation. Effective micro-aeration depends on several factors and is not fully mastered.
厌氧消化(AD)是一种成熟的废物/废水处理及沼气生产方法,但在提高其性能方面仍存在挑战,特别是对于脂质、碳氢化合物、多酚、药物及其他污染物等有毒/抑制性有机化合物。微曝气涉及控制引入少量氧气,已成为一种有前景的策略,可增强微生物活性、刺激难降解化合物的降解并提高甲烷产量。本文综述了用于有效氧气投加、测量和控制的不同策略,同时也深入探讨了厌氧和好氧共存途径的生物能学。综述了证明微曝气增强对顽固性有机污染物(如BTEX(苯、甲苯、乙苯和二甲苯)和药物化合物)厌氧处理潜力的研究。一些研究将微曝气用作预处理,而那些直接在生物反应器中实施微曝气的研究通常采用间歇式应用。然而,在大多数情况下,微曝气的应用是基于“试错”方法,对于不同类别的污染物,仍缺乏对最佳策略和投加量的系统理解。本文还探讨了微曝气在脂质厌氧消化中的多种作用,突出了驱动这些过程的关键微生物和潜在机制,例如兼性厌氧菌在将油酸转化为棕榈酸以及保护产甲烷群落中的作用。最后,本文强调了在应用微曝气进行有机污染物厌氧处理方面的未来方向和 remaining challenges。关键点:脂质、碳氢化合物、染料、药物及其他污染物的厌氧消化具有挑战性。微曝气重塑微生物群落并增强污染物降解。有效的微曝气取决于多个因素,尚未完全掌握。