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In this work, both short-term and long-term experiments were therefore conducted to assess the effects of ciprofloxacin (0.2 and 2 mg·L − 1 ) on wastewater nutrient removal. The results showed that both levels of ciprofloxacin had no acute and chronic adverse effects on the surface integrity and viability of activated sludge. Short-term exposure to all the ciprofloxacin levels induced negligible influences on wastewater nutrient removal. However, the prolonged exposure to ciprofloxacin decreased total phosphorus and nitrogen removal efficiencies from 96.8, 95.8% (control) to 91.7, 84.9% (0.2 mg·L − 1 ) and 90.5%, 80.2% (2 mg·L − 1 ), respectively. The mechanism study showed that ciprofloxacin exposure suppressed denitrification and phosphorus uptake processes. It was also found that ciprofloxacin affected the transformations of intracellular polyhydroxyalkanoates and glycogen in the oxic and anoxic stages. Moreover the activities of nitrite reductase and polyphosphate kinase were inhibited by the presence of ciprofloxacin. Further analysis with high-throughput sequencing revealed that compared with the control, the abundances of polyphosphate accumulating organisms, glycogen accumulating organisms and denitrifying bacteria in ciprofloxacin exposure reactors reduced, which were consistent with the decreased nutrient removal performance measured in these reactors. [ABSTRACT FROM AUTHOR]

Abstract: Lately, we have proved that biological phosphorus (P) removal can be achieved in the aerobic/extended-idle (AEI) regime using glucose as the sole carbon source, which might develop a potential simple strategy for simultaneous removal of P and organic substrates from wastewater. Since acetate and propionate are the two most common substrates present in real domestic wastewater, this paper further assesses the P removal performances in the AEI process using acetate and propionate as the sole carbon source. The results showed that 3.91 and 3.64mg of P/g of total suspended solids were, respectively, removed in the acetate-reactor and propionate-reactor after 50 days, respectively. After 90 days P removal in the propionate-reactor increased to 4.91mg P/g of total suspended solids whereas that in the acetate-reactor kept in the same level (3.98mg/g). Though both acetate and propionate could be used as carbon sources for P removal in such a novel system, the latter was more effective after long-term operation. Further investigations showed that, after 90 days’ acclimatization, sludge poly-P content in the propionate-system was more than that in the acetate-system, which was the primarily reason for the propionate-system showing higher P removal. [Copyright &y& Elsevier]

[Display omitted] • Simple synthesis of high-performance green materials from tourmaline and ZnAl-LDH. • Tourmaline surface electric field can effectively separate photogenerated electron holes. • TLLDH0.2 composites have good photocatalytic removal of mixed pollutants. • The TLLDH0.2/PMS/Vis system was highly effective in treating real sugar-containing wastewater. • The toxicity of the intermediates of enediamine and tetracycline was systematically evaluated. The photocatalytic reduction-induced activation of peroxymonosulfate (PMS) presents an eco-friendly and cost-effective approach for oxidatively degrading diverse organic pollutants in water. Nonetheless, the swift reconfiguration of photoinduced electron holes significantly hinders its overall efficiency. In this investigation, we present a novel photocatalytic persulfate activation system based on a ZnAl-LDH catalyst finely tuned by naturally polarized tourmaline (TL) minerals. The composite photocatalysts, TL/ZnAl-LDH, were employed to activate PMS for the simultaneous and efficient degradation of nitenpyram (NTP) and tetracycline hydrochloride (TC). In this system, the TL/ZnAl-LDH composite produced electrons and holes under light excitation. Subsequently, the photogenerated electrons from ZnAl-LDH on the TL surface activated PMS, leading to the formation of SO 4- •. Some of the SO 4- • further reacted with H 2 O/•OH to generate •OH. Ultimately, the NTP and TC were oxidized through the combined action of SO 4- •, •OH and photoinduced holes. Under the optimal conditions in the presence of PMS, TL/ZnAl-LDH degraded completely both NTP and TC within 45 min, with a 17 % mineralization rate. The findings indicate that the polarized electric field of TL not only promoted the separation and migration of electron-holes in ZnAl-LDH but also optimized the electronic structure of ZnAl-LDH. This optimization resulted in enhanced light absorption and improved reduction capacity. This study innovatively developed a system for activating photocatalytic PMS by incorporating naturally polarized minerals. This introduced a novel approach to sustainable and cost-effective advanced oxidation processes for water treatment. [ABSTRACT FROM AUTHOR]

Abstract Substantial consumption and widespread contamination of the available freshwater resources necessitate a continuing search for sustainable, cost-effective and energy-efficient technologies for reclaiming this valuable life-sustaining liquid. With these key advantages, capacitive deionization (CDI) has emerged as a promising technology for the facile removal of ions or other charged species from aqueous solutions via capacitive effects or Faradaic interactions, and is currently being actively explored for water treatment with particular applications in water desalination and wastewater remediation. Over the past decade, the CDI research field has progressed enormously with a constant spring-up of various cell architectures assembled with either capacitive electrodes or battery electrodes, specifically including flow-by CDI, membrane CDI, flow-through CDI, inverted CDI, flow-electrode CDI, hybrid CDI, desalination battery and cation intercalation desalination. This article presents a timely and comprehensive review on the recent advances of various CDI cell architectures, particularly the flow-by CDI and membrane CDI with their key research activities subdivided into materials, application, operational mode, cell design, Faradaic reactions and theoretical models. Moreover, we discuss the challenges remaining in the understanding and perfection of various CDI cell architectures and put forward the prospects and directions for CDI future development. Graphical abstract Image 1 Highlights • A comprehensive review on the recent advances of various CDI cell architectures provided. • CDI cells are assembled with either capacitive electrodes or battery electrodes. • CDI technologies are currently being actively explored for water treatment. • Prospects and directions for CDI future development are presented. [ABSTRACT FROM AUTHOR]

The growing increasing occurrence of perfluorooctanoic acid (PFOA) in wastewater has raised concerns about its potential impact on the environment. Nevertheless, the impact of PFOA at environmentally relevant level on the formation of aerobic granular sludge (AGS) is still a 'black box'. This study thus aims to fill this gap by comprehensive investigation of sludge properties, reactor performance and microbial community during the formation of AGS. It was found that 0.1 mg/L PFOA delayed the formation of AGS, causing relatively lower proportion of large size AGS at the end of operation process. Interestingly, the microorganisms contribute to the reactor's tolerance to PFOA by secreting more extracellular polymeric substances (EPS) to slow or block the entry of toxic substances into the cells. During the granule maturation period, the reactor nutrient removal especially chemical oxygen demand (COD) and total nitrogen (TN) were affected by PFOA, decreasing the corresponding removal efficiencies to ∼81.2% and ∼69.8%, respectively. Microbial analysis further revealed that PFOA decreased the abundances of Plasticicumulans , Thauera , Flavobacterium and Cytophagaceae_uncultured , but it has promoted Zoogloea and Betaproteobacteria_unclassified growth, which maintained the structures and functions of AGS. The above results revealed that the intrinsic mechanism of PFOA on the macroscopic representation of sludge granulation process was revealed, and it is expected to provide theoretical insights and practical support for direct adoption of municipal or industrial wastewater containing perfluorinated compounds to cultivate AGS. [Display omitted] • PFOA at environmentally relevant level delayed the formation of AGS. • PFOA exposure significantly increased polysaccharide and protein content in the EPS. • PFOA led to a decrease of reactor nutrient removal. • Microbial community of AGS changed after long-term PFOA exposure. [ABSTRACT FROM AUTHOR]