Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, China.
Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, 430070, China.
Chemosphere. 2024 Apr;353:141535. doi: 10.1016/j.chemosphere.2024.141535. Epub 2024 Feb 23.
Recovering resources from wastewater to alleviate the energy crisis has become the prevailing trend of technological development. Purple phototrophic bacteria (PPB), a group of fast-growing microbes, have been widely noticed for their potential in producing value-added products from waste streams. However, saline contents in these waste streams, such as food processing wastewater pose a big challenge, which not only restrain the pollutant removal efficiency, but also hinder the growth of functional microbes. To overcome this, a photo anaerobic membrane bioreactor cultivating PPB (PPB-MBR) was constructed and its performance upon long-term salinity stress was investigated. PPB-MBR achieved desirable pollutants removal performance with the average COD and NH removal efficiency being 87% (±8%, n = 87) and 89% (±10%, n = 87), respectively during long-term exposure to salinity stress of 1-80 g NaCl L. PPB were predominant during the entire operation period of 87 days (60%-80%), obtaining maximum biomass yield of 0.67 g biomass g COD and protein productivity of 0.18 g L d at the salinity level of 20 g NaCl L and 60 g NaCl L, respectively. The sum of value-added products in proportion to the biomass reached 58% at maximum at the salinity level of 60 g NaCl L with protein, pigments and trehalose contributing to 44%, 8.7%, and 5%, respectively. Based on economic analysis, the most cost-saving scenario treating food processing wastewater was revealed at salinity level of around 20 g NaCl L. However, more optimization tools are needed to boost the production efficiency so that the profit from value-added products can outweigh the additional cost by excess salinity in the future implication.
从废水中回收资源以缓解能源危机已成为技术发展的主流趋势。紫光合细菌（PPB）是一组生长迅速的微生物，由于其从废物流中生产增值产品的潜力而受到广泛关注。然而，这些废水中的盐分含量（如食品加工废水）带来了很大的挑战，不仅抑制了污染物去除效率，还阻碍了功能微生物的生长。为了克服这一问题，构建了一种培养 PPB 的光厌氧膜生物反应器（PPB-MBR），并研究了其在长期盐度胁迫下的性能。PPB-MBR 在长期暴露于 1-80 g NaCl L 的盐度胁迫下，实现了理想的污染物去除性能，COD 和 NH 的平均去除效率分别为 87%（±8%，n=87）和 89%（±10%，n=87）。在 87 天的整个运行期间，PPB 占主导地位（60%-80%），在 20 g NaCl L 和 60 g NaCl L 的盐度水平下，分别获得了最大生物质产量 0.67 g 生物质 g COD 和 0.18 g L d 的蛋白质生产力。与生物质成正比的附加值产品总和在 60 g NaCl L 的盐度水平下达到最大值，为 58%，其中蛋白质、色素和海藻糖分别贡献 44%、8.7%和 5%。基于经济分析，在 20 g NaCl L 左右的盐度水平下，处理食品加工废水的成本节约方案最为节省。然而，需要更多的优化工具来提高生产效率，以便在未来的应用中，从增值产品中获得的利润能够超过因盐分过多而增加的额外成本。
