Hongyi Lyu, Ruixiao Yan, Mengyi Wang, Tairan Liu, Suqi Li, Caiyun Yang and Yiqing Yao*,
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引用次数: 0
Abstract
Mechanical stirring is the most efficient method for enhancing solid-state anaerobic digestion (SS-AD). However, the current understanding of its mass and heat transfer is limited due to experimental constraints. Here, two 100 L SS-AD reactors were established: one with mechanical stirring and the other without. Temperature distributions were conducted to study heat transfer; computational fluid dynamics (CFD) was combined with the effective diffusion coefficient (Deff) to validate mass transfer. Environmental parameters were incorporated to determine the influence of heat and mass transfer on the microenvironment. The results revealed that the cumulative CH4 yield with mechanical stirring was increased by 32.21%. Mass transfer had a greater impact on the microenvironment and microbial communities’ distribution than heat transfer. During the start-up stage of AD, mechanical stirring facilitated the homogeneous dispersion of microorganisms. It promoted substrate hydrolysis, while reducing methanogenic potential on the peak CH4 production phase, indicating a lower intensity of mechanical stirring is required in the following methanogenesis stage. For this case, metagenome analysis confirmed that mechanical stirring enhanced microbial mobility and environmental adaptability. However, it limited microbial DNA synthesis, ribosome, and functions related to microbial reproduction, resulting in a reduction in the CH4 production potential of the reactor.
期刊介绍:
ACS ES&T Engineering publishes impactful research and review articles across all realms of environmental technology and engineering, employing a rigorous peer-review process. As a specialized journal, it aims to provide an international platform for research and innovation, inviting contributions on materials technologies, processes, data analytics, and engineering systems that can effectively manage, protect, and remediate air, water, and soil quality, as well as treat wastes and recover resources.
The journal encourages research that supports informed decision-making within complex engineered systems and is grounded in mechanistic science and analytics, describing intricate environmental engineering systems. It considers papers presenting novel advancements, spanning from laboratory discovery to field-based application. However, case or demonstration studies lacking significant scientific advancements and technological innovations are not within its scope.
Contributions containing experimental and/or theoretical methods, rooted in engineering principles and integrated with knowledge from other disciplines, are welcomed.