School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
Biodegradation. 2021 Dec;32(6):677-695. doi: 10.1007/s10532-021-09960-z. Epub 2021 Sep 13.
Biofilm process is a promising wastewater treatment technology and biofilm carrier (biocarrier) is regarded as the core of this process. However, the traditional commercial biocarriers have their inherent drawbacks, therefore, the development of new-type biocarrier to enhance wastewater treatment efficiency is significantly important to biofilm-based reactors. In this study, based on radical suspension polymerization, a novel kind of magnetic porous carriers (PMCs) was prepared by modifying the porous polymer carriers (PPCs) with inorganic particles, and then applied in a fluidized bed bioreactor (FBBR) with a low packing ratio of 10 % (v/v) to synthetic wastewater treatment. The results showed that this novel biocarrier possesses paramagnetism with saturation magnetization of 1.01emu/g, low density (1.26 g/cm), excellent hydrophilicity (surface water contact angle approaching zero) and rough surface. Besides, compared with the PPCs, the developed PMCs have larger pores (up to 50 μm or more), in which the larger-sized microbes are able to colonize. Moreover, as compared to the PPCs-based FBBR, the PMCs-based reactor achieved shorter time (7 days) for biofilm formaiton and significantly enhanced NH-N removal efficiency ( nearly 20 % increase at the level of influent NH-N concentration about 100 mg/L). High-throughput sequencing (HTS) results indicated that this new biocarrier could promote biodiversity and improve the abundance of Nitrosomonadales (the functional bacteria for ammonia removal in the bio-system), thus enhancing the ammonification process. Therefore, the developed PMCs could be preferable biocarriers for biofilm formation and provide an alternative to the traditional suspended biocarrier, demonstrating a promising potential, even at a lower filling ratio, to enhance the pollutants removal performance.
生物膜法是一种很有前途的污水处理技术，而生物膜载体（biocarrier）被认为是该工艺的核心。然而，传统的商业生物载体存在固有缺陷，因此，开发新型生物载体来提高废水处理效率对于基于生物膜的反应器具有重要意义。在本研究中，基于自由基悬浮聚合，通过用无机颗粒修饰多孔聚合物载体（PPCs），制备了一种新型磁性多孔载体（PMCs），并将其应用于填充比为 10%（v/v）的低填充比的流化床生物反应器（FBBR）中处理合成废水。结果表明，这种新型生物载体具有顺磁性，饱和磁化强度为 1.01emu/g，密度低（1.26g/cm），亲水性好（表面水接触角接近零），表面粗糙。此外，与 PPCs 相比，开发的 PMCs 具有更大的孔（可达 50μm 或更大），其中较大尺寸的微生物能够定植。此外，与 PPCs 为基础的 FBBR 相比，PMCs 为基础的反应器实现了更短的生物膜形成时间（7 天），并显著提高了 NH-N 去除效率（在进水 NH-N 浓度约为 100mg/L 的水平下，提高了近 20%）。高通量测序（HTS）结果表明，这种新型生物载体可以促进生物多样性，提高氨氮去除功能菌（Nitrosomonadales）的丰度，从而增强氨化过程。因此，开发的 PMCs 可以作为生物膜形成的理想载体，替代传统的悬浮生物载体，即使在较低的填充比下，也具有增强污染物去除性能的潜力。
