Algae show great potential as sustainable feedstock for numerous bioproducts. However, large volume of water consumption during algal biomass production makes that the culture media recycling is a necessity due to economic and environmental concern. To avoid the negative effect of enriched organic matters in the harvested culture media, pre-treatment prior to medium replenishment and reuse is required. In this study, degradation of algenitic organic matters (AOM) in the culture media by UV-based photolysis processes (i.e., direct UV, UV/peroxydisulfate (PDS), UV/H₂O₂, and UV/NH₂Cl) was explored. The results showed that UV, UV/PDS, UV/H₂O₂ and UV/NH₂Cl caused a decrease of SUVA for 29.9%, 35.4%, 40.45%, and 22.6%, respectively, though the organic matter was almost not mineralized. Fluorescence excitation-emission matrix combined with parallel factor analysis indicated that UV/PDS and UV/H₂O₂ degraded 47.26%–56.31% of the flulvic-like and humic-like fractions in AOM. Powder activated carbon absorption and growth evaluation for the AOPs-treated media indicated that UV/PDS and UV/H₂O₂ processes not only could remove the growth inhibitors in the media, but were also beneficial to the algae growth. These results suggested that UV/PDS and UV/H₂O₂ could effectively degrade the hydrophobic components in AOM and converted the growth inhibition fraction of AOM in the recycled media into nutrient source for algal growth. Different from the general application of UV-based AOP in the wastewater treatment, this study provided an innovative idea about how to pre-treat AOM in the media recycling: utilization rather than removal, which was a more sustainable and environment-friendly technology.

藻类作为多种生物产品的可持续原料具有巨大潜力。然而，由于经济和环境方面的考虑，藻类生物质生产过程中大量的水消耗使得培养基的再循环成为必要。为了避免收获的培养基中富集有机物的负面影响，需要在补充培养基和重复使用之前进行预处理。在这项研究中，通过基于UV的光解过程（即直接UV，UV /过二硫酸（PDS），UV / H ₂ O ₂和UV / NH ₂ Cl）降解了培养基中的藻类有机物（AOM）。探索。结果表明，UV，UV / PDS，UV / H ₂ O ₂和UV / NH ₂尽管有机物几乎未矿化，Cl引起的SUVA下降分别为29.9％，35.4％，40.45％和22.6％。荧光激发-发射矩阵结合并行因子分析表明，UV / PDS和UV / H ₂ O ₂降解了AOM中的类黄酮和类腐殖质分数的47.26％–56.31％。粉末活性炭对AOPs处理的培养基的吸收和生长评估表明，UV / PDS和UV / H ₂ O ₂工艺不仅可以去除培养基中的生长抑制剂，而且对藻类的生长也有好处。这些结果表明UV / PDS和UV / H ₂ O ₂可以有效降解AOM中的疏水成分，并将回收培养基中AOM的生长抑制率转化为藻类生长的营养源。与基于紫外线的AOP在废水处理中的一般应用不同，本研究提供了有关如何在介质回收中对AOM进行预处理的创新思路：利用而不是去除，这是一种更可持续，更环保的技术。