Membrane bioreactors for hospital wastewater treatment: recent advancements in membranes and processes

Abstract

Discharged hospital wastewater contains various pathogenic microorganisms, antibiotic groups, toxic organic compounds, radioactive elements, and ionic pollutants. These contaminants harm the environment and human health causing the spread of disease. Thus, effective treatment of hospital wastewater is an urgent task for sustainable development. Membranes, with controllable porous and nonporous structures, have been rapidly developed for molecular separations. In particular, membrane bioreactor (MBR) technology demonstrated high removal efficiency toward organic compounds and low waste sludge production. To further enhance the separation efficiency and achieve material recovery from hospital waste streams, novel concepts of MBRs and their applications are rapidly evolved through hybridizing novel membranes (non hydrophilic ultrafiltration/microfiltration) into the MBR units (hybrid MBRs) or the MBR as a pretreatment step and integrating other membrane processes as subsequent secondary purification step (integrated MBR-membrane systems). However, there is a lack of reviews on the latest advancement in MBR technologies for hospital wastewater treatment, and analysis on its major challenges and future trends. This review started with an overview of main pollutants in common hospital wastewater, followed by an understanding on the key performance indicators/criteria in MBR membranes (i.e., solute selectivity) and processes (e.g., fouling). Then, an in-depth analysis was provided into the recent development of hybrid MBR and integrated MBR-membrane system concepts, and applications correlated with wastewater sources, with a particular focus on hospital wastewaters. It is anticipated that this review will shed light on the knowledge gaps in the field, highlighting the potential contribution of hybrid MBRs and integrated MBRmembrane systems toward global epidemic prevention.

Polysulfone and cellulose acetate-based membranes' potential application to photocatalytic membrane reactors

“…However, the main drawback of membrane processes' large-scale adoption is represented by clogging and maintenance requirements [4,5]. Thus, the majority of research works in the field performed on laboratory or pilot installations are focusing on delivering to industry better membrane materials that allow less intensive operation/maintenance effort [6,7]. Polymeric membranes used for advanced treatment of municipal wastewater are starting from a large variety of polymers such as polysulfone (Psf), cellulose acetate (Ac-Cel), polyvinyl chloride, polyacrylonitrile etc.…”

Towards Effective, Sustainable Solution for Hospital Wastewater Treatment to Cope with the Post-Pandemic Era

“…If the MBR device does not effectively treat bacteria or viruses, the addition of a nanofiltration membrane (1-2 nm) or reverse osmosis membrane (0.1-0.7 nm) is necessary. Most bacteria and viruses (including SARS-CoV-2) have a diameter larger than these parameters, and thus the filtering ability is sufficient to eliminate these pathogenic microorganisms [5,20].…”

“…Thus, membrane bioreactors (MBRs) were employed to aid sludge-water separation. An MBR's built-in filter membrane has a small pore size and can filter the majority of pollutants in hospital wastewater [5]. Advanced techniques, such as Fenton oxidation, electrocoagulation, and the electro-peroxone process, can be used to successfully remove organic matter and drugs.…”

Fabrication of anti-biofouling and antibacterial polysulfone membrane via impregnation of silver nanoparticles

“…To treat wastewater, various systems are 12]. The production of extracellular polymeric used, but the membrane bioreactor (MBR) is widely substances (EPS) by microorganisms results in the used due to its ablated impression and excellent formation of a morphological framework of biofilm outflow [4,5,6]. However, membrane biofouling that clutches the microorganisms and ensures their prevents MBRs from being used widely [7].…”