Microplastics contamination in water supply system and treatment processes.

Due to global demand, millions of tons of plastics have been widely consumed, resulting in the widespread entry of vast amounts of microplastic particles into the environment. The presence of microplastics (MPs) in water supplies, including bottled water, has undergone systematic review, assessing the potential impacts of MPs on humans through exposure assessment. The main challenges associated with current technologies lie in their ability to effectively treat and completely remove MPs from drinking and supply water. While the risks posed by MPs upon entering the human body have not yet been fully revealed, there is a predicted certainty of negative impacts. This review encompasses a range of current technologies, spanning from basic to advanced treatments and varying in scale. However, given the frequent detection of MPs in drinking and bottled water, it becomes imperative to implement comprehensive management strategies to address this issue effectively. Consequently, integrating current technologies with management options such as life-cycle assessment, circular economy principles, and machine learning is crucial to eliminating this pervasive problem.

Characterization of reciprocation membrane bioreactor on treatment performance, energy consumption and membrane fouling.

Two reciprocating membranes (rMBR) with two frequencies of 0.46 Hz (rMBR-0.46) and 0.3 Hz (rMBR-0.3) were operated to compare the treatment performance and gross energy consumption with a conventional MBR. The average organic removal rates of MBR, rMBR-0.46 and rMBR-0.3 were maintained 295 ± 51; 823 ± 296; and 397 ± 129 mgCOD/gVSS.d, respectively. Nitrogen removal was enhanced in rMBR phases compared to conventional MBR phase due to anoxic membrane chamber. Further, fouling rate was found to be highest of 16.5 mbar/day (at conventional MBR phase), which was and much decreased to1.0 mbar/day (at rMBR-0.46 phase) and then 0.2 mbar/day (rMBR-0.3 phase). The reciprocation membrane also showed energy potential by saving 10.6% electricity for each treated cubic meter of wastewater compared to the conventional MBR.

Microfibers in laundry wastewater: Problem and solution.

Data corroborated in this study highlights laundry wastewater as a primary source of microfibers (MFs) in the aquatic environment. MFs can negatively impact the aquatic ecosystem via five possible pathways, namely, acting as carriers of other contaminats, physical damage to digestive systems of aquatic organisms, blocking the digestive tract, releasing toxic chemicals, and harbouring invasive and noxious plankton and bacteria. This review shows that small devices to capture MFs during household laundry activities are simple to use and affordable at household level in developed countries. However, these low cost and small devices are unrealiable and can only achieve up to 40 % MF removal efficiency. In line filtration devices can achieve higher removal efficiency under well maintained condition but their performance is still limited compared to over 98 % MF removal by large scale centralized wastewater treatment. These results infer that effort to increase sanitation coverage to ensure adequate wastewater treatment prior to environmental discharge is likely to be more cost effective than those small devices for capturing MFs. This review also shows that natural fabrics would entail significantly less environmental consequences than synthetic materials. Contribution from the fashion industry to increase the share of natural frabics in the current textile market can also reduce the loading of plastic MFs in the environment.

An overview of deploying membrane bioreactors in saline wastewater treatment from perspectives of microbial and treatment performance.

The discharged saline wastewater has severely influenced the aquatic environment as the treatment performance of many wastewater treatment techniques is limited. In addition, the sources of saline wastewater are also plentiful from agricultural and various industrial fields such as food processing, tannery, pharmaceutical, etc. Although high salinity levels negatively impact the performance of both physicochemical and biological processes, membrane bioreactor (MBR) processes are considered as a potential technology to treat saline wastewater under different salinity levels depending on the adaption of the microbial community. Therefore, this study aims to systematically review the application of MBR widely used in the saline wastewater treatment from the perspectives of microbial structure and treatment efficiencies. At last, the concept of carbon dioxide capture and storage will be proposed for the MBR-treating saline wastewater technologies and considered toward the circular economy with the target of zero emission.