Related Experiment Video
Updated: Feb 16, 2026
Validation of Therapeutic Agent Conjugation to Polyvinyl Alcohol-Coated Medical Devices
Published on: November 29, 2024
Immobilization of activated sludge using improved polyvinyl alcohol (PVA) gel
Li-sheng Zhang1, Wei-zhong Wu, Jian-long Wang
1Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China. zhanglisheng@tsinghua.org.cn
Abstract:
The microbial immobilization method using polyvinyl alcohol (PVA) gel as an immobilizing material was improved and used for entrapment of activated sludge. The oxygen uptake rate (OUR) was used to characterize the biological activity of immobilized activated sludge. Three kinds of PVA-immobilized particles of activated sludge, that is, PVA-boric acid beads, PVA-sodium nitrate beads and PVA-orthophosphate beads were prepared, and their biological activity was compared by measuring the OUR value. The bioactivity of both autotrophic and heterotrophic microorganisms of activated sludge was determined using different synthetic wastewater media (containing 250 mg/L COD and 25 mg/L NH(4+)-N). The experimental results showed that the bioactivity and stability of the three kinds of immobilized activated sludge was greatly improved after activation. With respect of the bioactivity and the mechanical stability, the PVA-orthophosphate method may be a promising and economical technique for microbial immobilization.
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