Rising concentrations of organic carbon (OC), phosphorus, and nitrogen in liquid waste from urban, industrial, and agricultural sources pose persistent challenges for environmental protection and resource recovery. Despite extensive application of microfiltration (MF) and ultrafiltration (UF) in wastewater treatment, their role in selective organic carbon and nutrient fractionation remains insufficiently clear-cut and is often interpreted solely through nominal pore size. This review was guided by the hypothesis that the reported limitations of MF and UF for nutrient separation are not intrinsic to the technologies but arise from simplified interpretations of separation mechanisms. A unified analytical framework was developed by synthesizing recent studies, linking membrane surface charge, pore structure, solute speciation, fouling-induced secondary layers, and operating conditions to the observed separation behavior. The analysis shows that MF fractionates particulate OC and suspended solids, whereas UF extends separation to macromolecular OC and phosphorus mainly via indirect retention mechanisms. Dissolved nitrogen species largely permeate both membranes unless they are transformed into retainable forms. Performance differences between MF and UF are conditional and system-dependent, with enhanced selectivity emerging through process integration. MF and UF can thus be repositioned as strategic fractionation interfaces within integrated treatment systems supporting circular economy–oriented wastewater management.

Bipolar membrane electrodialysis (BMED) is an electro-membrane separation technology used for over 20 years to treat liquid wastes, including wastewater from various industrial processes, municipal wastewater, and animal farms. This technology has been developed for its ability to dissociate H₂O into H⁺ and OH⁻ ions and to convert cations and anions in the feed solution into bases and acids, respectively, by applying an electrical potential. In comparison with alternative treatment technologies, BMED has some advantages, such as no need for chemical reagents, high degrees of efficiency, and straightforward operational procedures. However, BMED has been limited by a high level of preparation expense for BMs, membrane deposition, and ion loss during operation. This review mainly describes the principles and designs of BMED, their compositions along with their advantages and disadvantages, the membrane fouling and cleaning, and also the trend of their application in wastewater treatment. Finally, the results on nutrient recovery by BMED show that the performance of BMED depends on the nature of the ion exchange membranes used, the composition of the sample solution, the process conditions, and the configuration of the membrane stack.

Bipolar membrane electrodialysis (BMED) is an electro-membrane separation technology used for over 20 years to treat liquid wastes, including wastewater from various industrial processes, municipal wastewater, and animal farms. This technology has been developed for its ability to dissociate H₂O into H+ and OH⁻ ions and to convert cations and anions in the feed solution into bases and acids, respectively, by applying an electrical potential. In comparison with alternative treatment technologies, BMED has some advantages, such as no need for chemical reagents, high degrees of efficiency, and straightforward operational procedures. However, BMED has been limited by a high level of preparation expense for BMs, membrane deposition, and ion loss during operation. This review mainly describes the principles and designs of BMED, their compositions along with their advantages and disadvantages, the membrane fouling and cleaning, and also the trend of their application in wastewater treatment. Finally, the results on nutrient recovery by BMED show that the performance of BMED depends on the nature of the ion exchange membranes used, the composition of the sample solution, the process conditions, and the configuration of the membrane stack.

The increasing generation of liquid waste from agricultural, industrial, and municipal sources poses significant environmental challenges due to its high content of organic carbon (OC) and nutrients such as phosphorus and nitrogen. This review examined the effectiveness of membrane-based technologies, particularly microfiltration (MF) and ultrafiltration (UF), in separating and recovering these valuable compounds. Drawing on key literature indexed in Scopus, the review analyzed how membrane properties, operating conditions, and feed characteristics influence removal efficiency. The find-ings indicate that MF membranes primarily retain particulate organic matter and sus-pended solids (SS), with limited retention of phosphorus and nitrogen species. In con-trast, UF membranes exhibited superior performance in removing both OC and phos-phorus, and partially retain some nitrogen compounds depending on molecular size and charge. When combined with pre-treatment processes such as coagulation or ad-sorption, both MF and UF achieve higher nutrient removal rates. These membrane technologies showed promise not only in reducing pollutant loads but also in enabling nutrient recovery for potential reuse in agriculture. The optimization of membrane configuration and integration with other processes is essential for enhancing treatment performance and contributing to circular wastewater management strategies.