Granule-base immobilization of biomass is a potential method for a decent quality granular sludge cultivation. In this study, 3D polyvinyl alcohol (PVA) gel beads were chemically cross-linked via a simple NaOH-titration method. The PVA gel beads’ porous morphology was characterized using scanning electron microscope (SEM) and Brunauer–Emmette–Teller (BET), and their mechanical properties were evaluated by swelling rate and compressive stress tests. When cross-linking time was 10 min, high quality gel beads (P10) were synthesized, which demonstrated a homogeneous porous structure, good swelling rate, and high compressive strength. A mechanism for synthesis of the gel beads was proposed based on the results of Fourier transform infrared (FTIR) and X-ray diffractometer (XRD) analysis. Briefly, the intermolecular hydrogen bonds of PVA were firstly broken by NaOH to generate active bond of O–Na, which easily reacted with B(OH)₄⁻ to produce the PVA-boric acid gel beads. P10 showed excellent biocompatibility for anaerobic ammonia oxidation (anammox) biomass’ immobilization. After incubation for three months, well granule-base immobilized sludge on P10 was developed in up-flow reactor. The sludge had high abundance of anammox biomass and was in balance with other functional bacteria. This work provides a simple method for the rapid preparation of 3D PVA gel beads and verifies their potential in granule-base immobilization of biomass.

生物质的颗粒基固定化是一种用于生产质量适中的颗粒污泥的潜在方法。在这项研究中，通过简单的NaOH滴定法对3D聚乙烯醇（PVA）凝胶珠进行了化学交联。使用扫描电子显微镜（SEM）和Brunauer–Emmette–Teller（BET）表征了PVA凝胶珠的多孔形态，并通过溶胀率和压缩应力测试评估了它们的机械性能。当交联时间为10分钟时，合成了高质量的凝胶珠（P10），该凝胶珠具有均匀的多孔结构，良好的溶胀速率和较高的抗压强度。基于傅立叶变换红外光谱（FTIR）和X射线衍射仪（XRD）分析的结果，提出了一种凝胶珠的合成机理。简要地，₄ ^-以产生PVA-硼酸凝胶珠。P10对厌氧氨氧化（anammox）生物质的固定显示出优异的生物相容性。孵育三个月后，在向上流动的反应器中将P10上的颗粒状固定污泥充分沉淀。污泥具有很高的厌氧生物量，并且与其他功能性细菌保持平衡。这项工作提供了一种快速制备3D PVA凝胶珠的简单方法，并验证了它们在生物质的颗粒基固定化方面的潜力。