Design, modification, and evaluation of biofilm carriers for membrane aerated biofilm reactors: A review

The Membrane Aerated Biofilm Reactor (MABR) utilizes oxygen-permeable membranes as biofilm carriers and delivering oxygen through a “bubble-free aeration” approach. This mode has been proven to effectively enhance oxygen mass transfer efficiency and the efficient utilization of carbon sources. Therefore, the rational design and optimization of the performance of membrane carries have become crucial for improving the performance of the MABR. This paper systematically reviews the rational design, surface modification strategies and evaluation system for MABR carriers, focusing on how surface roughness, wettability, charge characteristics, and gas mass transfer influence microbial adhesion and biofilm formation. The study analyzes the mechanisms and application of different modification materials in optimizing carrier performance. Additionally, a comprehensive evaluation framework encompassing carrier physicochemical characterization, biofilm growth, and long-term operational performance has been established. Furthermore, the present paper highlights the challenges encountered: the selection between hydrophilic and hydrophobic surfaces, the toxicity of modification materials, and the balance between mass transfer capacity and antifouling performance. It also proposes that “functional bionic composite membranes” and “MABR rapid start-up strategies” may represent future development directions. By integrating the “concept-implementation-evaluation” research approach, the present study aims to provide theoretical guidance and technical references for developing high-performance MABR membrane materials.