Biological Processes Laboratory (LPB), São Carlos School of Engineering (EESC), University of São Paulo (USP), 1100 João Dagnone Avenue, São Carlos, São Paulo, Brazil.
Microbial Community Laboratory, BioGem Department, Ministry of Education, Biological Research Institute Clemente Estable, Avenida Italia, 3318, Montevideo, Uruguay.
Bioprocess Biosyst Eng. 2021 Jul;44(7):1405-1421. doi: 10.1007/s00449-021-02517-7. Epub 2021 Mar 15.
The high temperature in which sugarcane vinasse (SV) is generated (~ 90 °C) and the positive effect of higher temperatures in biochemical reactions have motivated the evaluation of SV anaerobic digestion (AD) under extreme temperature conditions. Two-stage (acidogenic/methanogenic) and single-stage (methanogenic) AD of SV were evaluated under 70 °C in structured-bed reactors. The extreme temperature was beneficial to the acidogenic step of the two-stage AD process. The methane production, however, was hindered at 70 °C. The VMP of the single and two-stage reactors accounted, respectively, for only 13% and 7% of the production rate reported in sugarcane vinasse AD at 55 °C. At 70 °C, the main genera responsible for methane production was Methanothermobacter and the acetoclastic methanogenesis did not occur, resulting in acetic acid build up (15,800 mg L). These results brought a new perspective for sugarcane vinasse management, with acetic acid production alternatively to methanization. In this perspective, two-stage process would be composed of acidogenic and acetogenic reactors, and beyond acetate, hydrogen and other soluble compounds could be recovered in a complete biorefinery process.
甘蔗废醪（SV）产生的高温（约 90°C）以及高温对生化反应的积极影响，促使人们在极端温度条件下评估 SV 厌氧消化（AD）。在结构床反应器中，70°C 下对 SV 进行了两段式（产酸/产甲烷）和一段式（产甲烷）AD 处理。极端温度有利于两段式 AD 工艺的产酸阶段。然而，在 70°C 时，甲烷的生成受到阻碍。单级和两级反应器的 VMP 分别仅占 55°C 下甘蔗废醪 AD 报告产率的 13%和 7%。在 70°C 时，主要负责甲烷生成的属是 Methanothermobacter，并且不会发生乙酸同化产甲烷作用，导致乙酸积累（15800mg/L）。这些结果为甘蔗废醪的管理带来了新的视角，可以替代甲烷化来生产乙酸。在这种情况下，两段式工艺将由产酸和产乙酸反应器组成，除了乙酸之外，还可以在完整的生物炼制过程中回收氢气和其他可溶性化合物。
