Mainka Thomas, Herwig Christoph, Pflügl Stefan
Institute for Chemical, Environmental and Bioscience Engineering, TU Wien, Vienna, Austria.
Competence Center CHASE GmbH, Linz, Austria.
Front Bioeng Biotechnol. 2022 Apr 19;10:896576. doi: 10.3389/fbioe.2022.896576. eCollection 2022.
Integrating bioprocess solutions for treatment and subsequent reuse of saline residual process brine into industrial processes could increase the sustainability of production chains. However, such bioprocesses require large-scales and a robust operation over a prolonged period. Consequently, the aim of this study was to analyze scale-up equivalence as well as continuous and stable process performance of a previously established lab scale process for the degradation of organic contaminants (formate and aromatic compounds) in an industrial context. To that end, a pilot-scale bubble column bioreactor system equipped with a membrane-based cell retention system for process intensification was integrated at an industrial production site. The process was successfully scaled-up and continuously operated for more than 210 days. Overall, the process proved to be robust towards changing compositions of the residual process brine stream and degradation rates for organic contaminants were close to 100%. Interestingly, due to the unsterile process conditions, the original culture was replaced by a novel halophilic bacterial community consisting of three bacterial genera. To further improve process economics and productivity, an optimization of the co-substrate feeding strategy for glycerol is required, as results indicated a potential correlation between glycerol feeding and formate degradation rates. To that end, decoupling of the glycerol feeding from the residual process brine feed is a potential way to increase process control options and allow for easy adaptation of the process to changing residual process brine compositions. Ultimately, the process described here could be a promising alternative for chemical or physical methods of treating residual process brine and once more underlines the potential to exploit natural microbial diversity for industrial purposes.
将生物过程解决方案集成到工业生产过程中，用于处理含盐工业残留盐水并随后进行回用，这可以提高生产链的可持续性。然而，此类生物过程需要大规模且长期稳定运行。因此，本研究的目的是在工业背景下分析先前建立的实验室规模的有机污染物（甲酸盐和芳香族化合物）降解过程的放大等效性以及连续稳定的过程性能。为此，在一个工业生产现场集成了一个中试规模的鼓泡塔生物反应器系统，该系统配备了基于膜的细胞截留系统以强化过程。该过程成功放大并连续运行了210多天。总体而言，该过程对于残留工艺盐水组成的变化具有很强的耐受性，有机污染物的降解率接近100%。有趣的是，由于非无菌的工艺条件，原来的培养物被一个由三个细菌属组成的新型嗜盐细菌群落所取代。为了进一步提高过程经济性和生产率，需要优化甘油共底物的进料策略，因为结果表明甘油进料与甲酸盐降解率之间存在潜在关联。为此，将甘油进料与残留工艺盐水进料解耦是增加过程控制选项并使该过程易于适应残留工艺盐水组成变化的一种潜在方法。最终，本文所述的过程可能是处理残留工艺盐水的化学或物理方法的一个有前途的替代方案，并再次强调了利用天然微生物多样性用于工业目的的潜力。
