Reactive Oxygen Species Generated in Situ During Carbamazepine Photodegradation at 222 nm Far-UVC: Unexpected Role of HO Molecules.

When 222 nm far-UVC is used to drive AOPs, photolysis emerges as a critical pathway for the degradation of numerous organic micropollutants (OMPs). However, the photodegradation mechanisms of the asymmetrically polarized OMPs at 222 nm remain unclear, potentially posing a knowledge barrier to the applications of far-UVC. This study selected carbamazepine (CBZ), a prevalent aquatic antiepileptic drug that degrades negligibly at 254 nm, to investigate its photodegradation mechanisms at 222 nm.

Nitrate Enhanced Sulfamethoxazole Degradation by 222 nm Far-UVC Irradiation: Role of Reactive Nitrogen Species.

The application of 222 nm far-UVC irradiation for degrading organic micropollutants in water shows promise. Nitrate (NO), found in nearly all water bodies, can significantly impact the performance of 222 nm far-UVC-driven systems. This work was the first to investigate the effect of NO on sulfamethoxazole (SMX) photodegradation at 222 nm, finding that NO significantly enhances SMX degradation in different dissociated forms.

Ultraviolet technology application in urban water supply and wastewater treatment in China: Issues, challenges and future directions.

This study thoroughly explores the application of Ultraviolet (UV) water treatment technology in urban wastewater treatment and water supply in China, highlighting its crucial role in enhancing water quality safety. UV technology, with its environmentally friendly and low-carbon characteristics, is deemed more in line with the demands of sustainable development compared to traditional chemical disinfection methods. The widespread application of UV technology in urban wastewater treatment in China, particularly in the context of urban sewage treatment, is examined.

Synergetic effect on fouling alleviating of membrane distillation in urine resource recovery by thermally activated peroxydisulfate pretreatment.

Given that the spontaneous precipitation of minerals caused by urea hydrolysis and abundant organic compounds, membrane fouling became a major obstacle for urine recovery by membrane distillation (MD). Herein, this study developed a combined system (TAP-MD) by integrating thermally activated peroxydisulfate (TAP) and MD process to inhibit membrane fouling and improve separation efficiency. Based on the TAP-MD system, the separation performance was improved significantly, improving nutrient recovery efficiency and quality of reclaimed water.

Machine-learning-aided application of high-gravity technology to enhance ammonia recovery of fresh waste leachate.

Stripping is widely applied for the removal of ammonia from fresh waste leachate. However, the development of air stripping technology is restricted by the requirements for large-scale equipment and long operation periods. This paper describes a high-gravity technology that improves ammonia stripping from actual fresh waste leachate and a machine learning approach that predicts the stripping performance under different operational parameters.

Comprehensive understanding of fluoroquinolone degradation via MPUV/PAA process: Radical chemistry, matrix effects, degradation pathways, and toxicity.

The wide occurrence of fluoroquinolones (FQs) in aquatic environments has aroused increasing concern about their potential adverse effects on human health. In this study, an emerging advanced oxidation process, i.e.

Contribution of filtration and photocatalysis to DOM removal and fouling mechanism during in-situ UV-LED photocatalytic ceramic membrane process.

The use of ceramic membranes and ultraviolet light-emitting diodes (UV-LEDs) has advanced the application of photocatalytic membrane for water treatment. We systematically evaluated the contribution of filtration and photocatalysis to dissolved organic matter (DOM) removal and fouling mechanism during in-situ UV-LED photocatalytic ceramic membrane filtration. The results showed that physical rejection primarily led to removal of 4-15 kDa molecules and photocatalysis further increased the removal of 1-4 kDa molecules, causing small sized microbial humic-like or protein-like materials in the permeate.

Characterization of microplastics in the septic tank via laser direct infrared spectroscopy.

Microplastics (MPs) are emerging pollutants that have been widely detected in the atmosphere, hydrosphere, lithosphere, and biosphere. Such wide spread of MPs indicates that the effective control in different environmental sectors is in an urgent need, and the first step in meeting this need is to identify the occurrence of MPs in the relevant environment. However, research on MPs in septic tanks has not been reported so far.

Antibiotics degradation by UV/chlor(am)ine advanced oxidation processes: A comprehensive review.

Antibiotics are emerging contaminants in aquatic environments which pose serious risks to the ecological environment and human health. Advanced oxidation processes (AOPs) based on ultraviolet (UV) light have good application prospects for antibiotic degradation. As new and developing UV-AOPs, UV/chlorine and derived UV/chloramine processes have attracted increasing attention due to the production of highly reactive radicals (e.

Insight into the degradation of ciprofloxacin by medium-pressure UV-activated monochloramine process.

The degradation efficiency and mechanisms of ciprofloxacin (CIP), a typical antibiotic, by a medium-pressure ultraviolet/chloramine (MPUV/NHCl) treatment were investigated. The results showed that CIP degradation by MPUV/NHCl was significantly higher than that by NHCl oxidation and MPUV photolysis, and that this degradation processes were consistent with pseudo-first-order kinetics. The initial CIP concentration (7.

Can we shape microbial communities to enhance biological activated carbon filter performance?

A new focus on biofiltration has emerged that aims to shape microbial communities to improve treatment efficacy. It is therefore necessary to understand the linkages between microbial community structure and biofilter function. However, the assembly and interaction of microbial communities in biological activated carbon (BAC) filters are unknown.

Ultraviolet-Light-emitting-diode activated monochloramine for the degradation of carbamazepine: Kinetics, mechanisms, by-product formation, and toxicity.

Monochloramine (NHCl) oxidant combined with a Ultraviolet (UV)-Light-emitting-diode (LED) light source forms a new advanced oxidation process (AOP), which can achieve high-efficiency degradation of carbamazepine (CBZ). The degradation of CBZ displayed pseudo-first-order reaction kinetics (R > 0.98, k = 0.

Degradation and transformation of norfloxacin in medium-pressure ultraviolet/peracetic acid process: An investigation of the role of pH.

Given that fluoroquinolone antibiotics (FQs) are frequently detected in aquatic environments, there is an urgent need for the development of efficient water treatment technologies for their removal. Peracetic acid (PAA)-based advanced oxidation processes (AOPs) have increasingly attracted attention as promising technologies for water decontamination in this regard. In this study, a novel PAA-based AOP (the medium-pressure ultraviolet (MPUV)/PAA process) was employed to degrade norfloxacin (NOR), which is an extensively applied FQ that is widely present in water.

Implication on selection and replacement of granular activated carbon used in biologically activated carbon filters through meta-omics analysis.

Biologically activated carbon (BAC) filters are widely used in China and worldwide as an essential part of advanced water treatment. However, it is unclear how to properly select the granular activated carbon (GAC) used in BAC filters and to determine when GAC should be replaced. In this study, five BAC filters, each filled with a different coconut- or coal-based GAC with different physicochemical properties, were run continuously for 400 days.

Peracetic acid-based advanced oxidation processes for decontamination and disinfection of water: A review.

Peracetic acid (PAA) has attracted growing attention as an alternative oxidant and disinfectant in wastewater treatment due to the increased demand to reduce chlorine usage and control disinfection byproducts (DBPs). These applications have stimulated new investigations on PAA-based advanced oxidation processes (AOPs), which can enhance water disinfection and remove micropollutants. The purpose of this review is to conduct a comprehensive analysis of scientific information and experimental data reported in recent years on the applications of PAA-based AOPs for the removal of chemical and microbiological micropollutants from water and wastewater.

Insight into PPCP degradation by UV/NHCl and comparison with UV/NaClO: Kinetics, reaction mechanism, and DBP formation.

The UV/NHCl process is an emerging advanced oxidation process (AOP) that is greatly effective in degrading pharmaceuticals and personal care products (PPCPs). However, detailed information regarding the process is lacking. The degradation of ibuprofen (IBP, an electron-withdrawing PPCP) and naproxen (NPX, an electron-donating PPCP) in UV/NHCl and UV/NaClO processes was performed to investigate the applicability and security of the UV/NHCl process and compare with those of UV/NaClO.

Effect of granular activated carbon pore-size distribution on biological activated carbon filter performance.

Proper granular activated carbon (GAC) selection could improve the performance of biological activated carbon (BAC) filters through a combination of adsorption and biodegradation, while the GACs used in BAC filters are now mainly selected according to adsorption function, ignoring biodegradation. In this study, sand filter effluent obtained from a drinking water treatment plant was fed into continuous-flow bench-scale BAC columns operated in parallel over 245 days to examine the effects of GAC pore-size distribution on BAC filter performance, in terms of the dissolved organic carbon (DOC) and disinfection byproduct (DBP) precursors. A metagenomic analysis indicated that bacterial community structure played an important role in BAC filter performance.

Ceramic nanocomposite membranes and membrane fouling: A review.

Membrane technologies have broad applications in the removal of contaminants from drinking water and wastewater. In recent decades, ceramic membrane has made rapid progress in industrial/municipal wastewater treatment and drinking water treatment owing to their advantageous properties over conventional polymeric membrane. The beneficial characteristics of ceramic membranes include fouling resistance, high permeability, good recoverability, chemical stability, and long life time, which have found applications with the recent innovations in both fabrication methods and nanotechnology.

The impact of UV treatment on microbial control and DBPs formation in full-scale drinking water systems in northern China.

To manage potential microbial risks and meet increasingly strict drinking water health standards, UV treatment has attracted increasing attention for use in drinking water systems in China. However, the effects of UV treatment on microbial control and disinfection by-products (DBPs) formation in real municipal drinking water systems are poorly understood. Here, we collected water samples from three real drinking water systems in Beijing and Tianjin to investigate the impacts of UV treatment on microbial control and DBP formation.

Bioremoval of non-steroidal anti-inflammatory drugs by Pseudoxanthomonas sp. DIN-3 isolated from biological activated carbon process.

The presence of non-steroidal anti-inflammatory drugs (NSAIDs) in the environment is an emerging concern owing to their potential threat on aquatic ecosystems and living organisms. To investigate the bioremoval potential of a biological activated carbon (BAC) filter for the removal of NSAIDs, removal of diclofenac (DCF), ibuprofen (IBU), and naproxen (NAP) by biofilms on a bench-scaled BAC column operated for 400 days was studied. The results showed that the BAC column effectively removed the three NSAIDs (>90%).

Mechanisms and toxicity evaluation of the degradation of sulfamethoxazole by MPUV/PMS process.

In this work, a sulfate radical (SO)-based advanced oxidation process was applied to the degradation of sulfamethoxazole (SMX). In these experiments, a medium pressure UV (MPUV) lamp was employed to active peroxymonosulfate (PMS). It was found that 98% of SMX was removed by MPUV/PMS at a UV dose of 200 mJ cm (3.

A comparison of genotoxicity change in reclaimed wastewater from different disinfection processes.

Effluents before disinfection from four wastewater reclamation plants were treated with chlorine (Cl), ozone (O), chlorine dioxide (ClO), medium-pressure ultraviolet (MPUV) and four different combinations of the above, to evaluate the effect of disinfection processes on the genotoxicity removal by the SOS/umu test. Results showed that the genotoxicity increased after MPUV irradiation (10-100 mJ/cm), but declined when adopting other disinfection processes. The effectiveness of genotoxicity reduction by five chemical disinfectants was identified as: O > pre-ozonation with Cl ≈ ClO > combination of ClO and Cl > Cl.

[Characteristics of Disinfection By-products and Genotoxicity During Drinking Water Disinfection with Potassium Monopersulfate Compound Powder].

The qualitative analysis for by-products in the course of disinfection of the raw water and the effluent of GAC in Beijing Tiancuishan Drinking Water Treamtment Plant by potassium monopersulfate compound powder was determined. Halogen disinfection by-products during disinfection process by potassium monopersulfate compound powder was evaluated in a bench scale by comparing with chlorine disinfection process, and the genotoxicity evaluation of potassium monopersulfate compound powder and chlorine disinfection processes was also conducted by -test. The results showed that there were small changes in the organic pollutant components of water samples after disinfection by potassium monopersulfate compound powder, while some new halogen disinfection by-products were generated.