College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China.
Sanya Oceanographic Institution, Ocean University of China, Sanya 572000, China.
Int J Environ Res Public Health. 2023 Jan 24;20(3):2117. doi: 10.3390/ijerph20032117.
The application of reclaimed water has been recognized as the key approach for alleviating water scarcity, while its low quality, such as high nitrogen content, still makes people worry about the corresponding ecological risk. Herein, we investigated the feasibility of removing residual nitrate from reclaimed water by applying . It is found that 15 mg/L total nitrogen could be decreased to 1.8 mg/L in 5 days, equaling 88.1 % removal efficiency under the optimized conditions. The deficient phosphorus at 0.5-1.0 mg/L was rapidly eliminated but was already sufficient to support nitrate removal by . The produced ammonia is generally below 0.2 mg/L, which is much lower than the standard limit of 5 mg/L. In such a nutrient deficiency condition, could maintain biomass growth well via photosynthesis. The variation of pigments, including chlorophyll a and carotenoids, suggested a certain degree of influences of illumination intensity and phosphorus starvation on microalgae. The background cations Cu and Zn exhibited significant inhibition on biomass growth and nitrate removal; thus, more attention needs to be paid to the further application of microalgae in reclaimed water. Our results demonstrated that cultivation of should be a very promising solution to improve the quality of reclaimed water by efficiently removing nitrate and producing biomass.
再生水的应用已被认为是缓解水资源短缺的关键途径，但其低质量，如高氮含量，仍让人担心其相应的生态风险。在此，我们研究了应用 从再生水中去除残留硝酸盐的可行性。结果发现，在优化条件下，15mg/L 的总氮可在 5 天内降低至 1.8mg/L，去除率达 88.1%。不足 0.5-1.0mg/L 的磷迅速被去除，但已足以支持 去除硝酸盐。产生的氨一般低于 0.2mg/L，远低于 5mg/L 的标准限值。在这种营养缺乏的情况下，通过光合作用可以很好地维持 的生物量生长。包括叶绿素 a 和类胡萝卜素在内的色素的变化表明，光照强度和磷饥饿对微藻有一定程度的影响。背景阳离子 Cu 和 Zn 对生物量生长和硝酸盐去除有明显的抑制作用；因此，需要进一步关注微藻在再生水中的应用。我们的结果表明，培养 是一种很有前途的解决方案，可以通过有效去除硝酸盐和生产生物量来提高再生水的质量。
