从富含乳糖的废水中生产乳酸盐:对反应堆配置进行比较研究,以最大限度地提高转换率和效率
Monika Temovska1, Richard Hegner1, Andrés E Ortiz-Ardila1
1Environmental Biotechnology Group, Department of Geosciences, University of Tübingen, Schnarrenbergstr. 94-96, 72076 Tübingen, Germany.
Water research
|March 1, 2025
概括
这项研究优化了使用连续生物反应器从酸乳清中生产乳酸盐的生产. 无氧过反应堆 (AFR) 和连续水箱反应堆 (CSTR) 显示出卓越的性能,实现了高转换率和产量.
科学领域:
- 生物技术和工业微生物学
- 生物化学工程 生物化学工程
- 废弃物价值化 废弃物价值化 废弃物价值化
背景情况:
- 全球乳酸盐生产主要依赖于批量培养中的糖的细菌发酵.
- 酸性乳清是富含乳糖的工业废水,为乳酸合成提供了未充分利用的基质.
- 与传统方法相比,随着生物质保留的持续生物反应器运行可降低成本并提高生产率.
研究的目的:
- 确定最佳的反应堆配置,以从酸乳清中持续生产乳酸盐,同时保留生物质.
- 研究不同液压保留时间 (HRT) 对乳酸生产效率的影响.
- 评估上游无氧污泥毯 (UASB),无氧过反应堆 (AFR) 和连续水箱反应堆 (CSTR) 配置的性能.
主要方法:
- 在连续模式下运行三个不同的生物反应器配置 (UASB,AFR,CSTR与空心纤维膜).
- 丰富的内源性D-乳酸盐生产的乳酸菌种. 没有外部注射剂,达到主导地位 (>90%).
- 在50°C和pH值5.0下测试了各种液压保留时间 (HRT),使用稀释的酸乳清减轻基质抑制.
主要成果:
- 未分离的乳酸度高于60mmol C L−1.1. 的乳酸生产被抑制.
- 缩短HRT (0.6天) 和稀释基质提高了糖转化效率.
- 由于增强细胞保留,AFR和CSTR表现出优于UASB的性能.
- 在CSTR中的pH控制错误导致恢复后改善了乳糖和银河糖到乳酸盐 (LG-to-LA) 的转化效率.
- 在CSTR实现的最大乳酸转化率为1256±46.3 mmol C L−1 d−1与82.2±3.4%的LG-into-LA效率和收益率为0.85±0.02 mmol C mmol C−1.1.
结论:
- 具有生物质保留的连续生物反应器,特别是AFR和CSTR,对于从酸乳清中生产高效乳酸盐是有效的.
- 优化的HRT和基质稀释对于克服抑制和最大化糖转化至关重要.
- CSTR配置表现出了卓越的性能,突出了其从乳制品废水中进行工业规模乳酸盐合成的潜力.
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