Abstract Splitting anaerobic digestion processes into two reactors may be biologically advantageous, but their separation in two stages significantly increases energetic costs. Therefore, the aim of this work was to study the energetic feasibility of a two-stage system producing hydrogen and methane by anaerobically co-digesting whey and glycerin in a sequencing batch reactor. The highest methane productivity (185.9 molCH4.m−3.d−1) was achieved when the reactor was operated in fed-batch mode at 11.8 kgCOD.m−3.d−1. The energy produced by treating all the whey from a dairy industry was estimated. We proposed a system of three reactors operating in parallel (194.4 m3 each) that produces hydrogen continuously, followed by three other reactors of 5.2 m³ each, also in parallel, to produce methane from the effluent of the acidogenic reactors. The total energetic yield of the two-stage system would be 7.0 MJ.kgCODremoved−1 and the monthly savings could reach up to US$ 8170, which leads to a technically feasible system. However, care must be taken when using a two-stage system for treatment of easily biodegradable substrates (whey and glycerin), because it will only have a better overall energetic yield if the single-stage system has a poor performance, i.e. a yield of 8.8 molCH4.kgCODremoved−1 or less.

中文翻译：

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与处理乳清和甘油的单级系统相比，两级厌氧消化系统的能量可行性

摘要 将厌氧消化过程分成两个反应器可能在生物学上是有利的，但它们在两个阶段的分离会显着增加能源成本。因此，这项工作的目的是研究通过在序批式反应器中厌氧共消化乳清和甘油来生产氢气和甲烷的两阶段系统的能量可行性。当反应器在补料分批模式下以 11.8 kgCOD.m-3.d-1 运行时，可实现最高的甲烷生产率 (185.9 molCH4.m-3.d-1)。估算了处理来自乳制品行业的所有乳清所产生的能量。我们提出了一个由三个平行运行的反应器（每个反应器 194.4 立方米）组成的系统，连续生产氢气，然后是另外三个反应器，每个反应器 5.2 立方米，也平行运行，从产酸反应器的流出物中生产甲烷。两级系统的总能量产量为 7.0 MJ.kgCODremoved−1，每月可节省高达 8170 美元，从而形成技术上可行的系统。然而，在使用两级系统处理易生物降解的底物（乳清和甘油）时必须小心，因为如果单级系统性能不佳，它只会有更好的整体能量产量，即产量为8.8 molCH4.kgCODremoved−1 或更少。