ACS ES&T water最新文献

The reuse of ozone-treated wastewater, especially for agricultural irrigation, is a crucial strategy to address water scarcity. However, the storage of ozone-treated wastewater contributes to the growth of potentially pathogenic bacteria. This study explores using nanosilver-loaded hydrogels as liners in storage containers to provide sustained antibacterial effects. The results indicate that the antibacterial effect of nanosilver-loaded hydrogels, possessing a three-dimensional porous network structure, is more efficient due to a relatively low concentration of nanosilver in the stored water while increasing the concentration in the immediate vicinity of K-12 Escherichia coli (E. coli) anchored in the pores. The antibacterial mechanism of nanosilver against K-12 E. coli involves a process termed pseudo cuproptosis. Nanosilver did not lead to a significant reduction in basal or ATP-linked respiration, but it did notably decrease the spare capacity of respiration and disrupt bacterial metabolism by binding to lipoylated proteins, including 2-oxoglutarate dehydrogenase E2 subunit (sucB) and dihydrolipoamide S-acetyltransferase (aceF), which are related to the tricarboxylic acid cycle. It also leads to the oligomerization of aceF, and finally causes proteotoxicity to the K-12 E. coli. This process is distinct from known bacterial growth stasis pathways. By understanding this mechanism, the dosage of nanosilver can be effectively controlled, ensuring the safety and efficacy of wastewater reuse for agricultural purposes in the near future.

Globally intensified lake system degradation has been attributed to high-intensity disturbance and emerged as a significant driver of the declines in lake biodiversity and ecosystem stability. However, potential alterations in feedback mechanisms between aquatic plants and microorganisms after ecological succession are still unclear. This study delves into the influence of aquatic plants on sediment bacterial diversity and nutrient dynamics across different growth phases using Illumina MiSeq sequencing and diffusive gradients in thin film analysis. Our results indicate that the surface temperature of the research area has increased from 20 to 28 °C over the past 25 years, and the dominant species has shifted to Stuckenia pectinata. Constructive species show responsive changes in their organ’s stoichiometric characteristics to adapt to environmental changes. The growth of S. pectinata could affect the diffusion fluxes of NH₄⁺–N, NO₃^––N, P, and Fe at the sediment–water interface. Morever, the deterministic processes of environmental filtering and competition may have altered the microorganisms in the rhizosphere of S. pectinata, temperature, and water depth were major drivers of seasonal microbial changes. These results in the driver-response relationship of multiple stressors in the lake ecosystem may contribute to the development of engineering projects focusing on restoring aquatic plants.

Fenton oxidation is highly efficient for removing pollutants from wastewater. However, the low utilization efficiency of oxidants increases operating costs and limits their application in water treatment. To address these issues, this study designed a novel Fenton-like catalyst: zerovalent iron/amorphous manganese composites (ZVI-Mn). This catalyst can activate O₂ in situ to generate H₂O₂ and simultaneously activate H₂O₂ to produce free radicals, achieving a 96.3% removal efficiency of enrofloxacin (ENR) from water. Radical quenching experiments showed that superoxide radicals (•O^2–) (46%) play a dominant role in ENR removal, while hydroxyl radicals (•OH) (28.2%) and singlet oxygen (¹O₂) (25.8%) also participate. Liquid chromatography–mass spectrometry (LC–MS), density functional theory (DFT) calculations, and toxicity estimations demonstrated effective ENR degradation and significant toxicity reduction of the intermediates, primarily through decarboxylation and ring opening. Additionally, ZVI-Mn achieved a 90.1% removal efficiency of ENR in aquaculture wastewater. This study proposes a new Fenton oxidation technique based on the in situ generation of H₂O₂, providing a meaningful research basis for environmentally friendly water treatment technologies.

Nitrate-induced spallation of lead-bearing solder particles into drinking water is not sufficiently controlled by phosphate-based inhibitors, although adding zinc can improve their performance. Studies using copper coupons coated with new lead–tin solder in water with up to 12 mg/L nitrate demonstrated that zinc orthophosphate reduced lead release by more than 90% and outperformed orthophosphate alone. Lead release and spallation from harvested pipes with decades-old lead–tin solder in a high nitrate water were improved but not eliminated with zinc orthophosphate over a period of months. When applied at a water utility with high source water nitrate, monthly in-home field sampling showed that 90th percentile lead levels dropped below the action level after dosing zinc orthophosphate at full scale for 6 months. Scanning electron microscopy (SEM) analysis of pipe scales revealed that zinc and orthophosphate codeposit at the copper–solder interface and may act as a mixed inhibitor, with zinc inhibiting the cathodic reaction on the copper pipe, phosphate limiting the anodic reaction, and an added benefit of zinc orthophosphate preferentially precipitating at the galvanic interface between the anode and the cathode. Updates to corrosion control guidance for waters with higher nitrate due to seasonal runoff or source water changes are needed.

Zinc orthophosphate reduced nitrate-induced solder corrosion in laboratory studies and at a water utility. It was found to reduce anodic and cathodic corrosion while preferentially precipitating at the copper–solder interface.

Hurricane Hanna brought unprecedented rainfall and flooding to Texas in 2020. Our study evaluated microbial contamination in surface water (SW) and groundwater (GW) across rural communities in Rio Grande Valley (RGV) and Baffin Bay using both culture-based and qPCR methods. Sampling began immediately after the landfall of Hurricane Hanna (August 2020) and until the end of the summer monsoon (August 2021). High concentrations of culturable Escherichia coli and total coliforms were detected during summer monsoon for both surface and GW. E. coli and enterococci were present in all SW samples in RGV. Enterococci was detected in all SW samples collected from BB; however, E. coli was detected in 81% of samples. Like SW, concentration of E. coli and enterococci markers in GW samples were high in RGV. The human-associated fecal marker (HF183) was detected in both SW and GW but mainly in RGV during the dry period. HF183 exhibited a low to moderate correlation with conventional fecal indicators, suggesting the uncertainty of enterococci and E. coli for detection of human fecal pollution. In general, the outcomes of this study serve as foundational data for subsequent investigations aimed at overseeing both established and evolving public health concerns for Texas residents.

Molecular dynamics (MD) simulations are conducted to assess the Li recovery performance of three zeolitic imidazolate frameworks (ZIFs) employed as selective layers in cation exchange membranes (CEMs) for flow capacitive deionization (FCDI). The three ZIFs (ZIF-8, ZIF-8-Cl, and ZIF-8-Br) share a common metal node (Zn node) but differ in their functional groups on the imidazolate linkers (CH₃, Cl, and Br). The performance of the ZIFs is evaluated based on their Li⁺/Na⁺ selectivity, determined by calculating the number of Li⁺ and Na⁺ ions in the flow-electrode. The adsorption of cations by the ZIFs is also investigated using graphs and contour maps depicting the ZIF–cation interaction energy. Additionally, the simulation results are validated through experiments involving the quantification of cation concentration in the feed solution. The results indicate that Li⁺/Na⁺ selectivity depends on the cation affinity of the ZIF. It is preferable to recover Li⁺ ions from the flow-electrode than from the CEM. Moreover, cations require external energy to enter the pores as they experience repulsion. To achieve high Li⁺/Na⁺ selectivity in the flow-electrode, the ZIF selective layers should exhibit a stronger affinity for Na⁺ than for Li⁺. Additionally, the cavities at the surface of the ZIFs should be sufficiently small to restrict Na⁺ entry. Overall, MD simulations are valuable for understanding the mechanisms necessary to achieve high Li⁺/Na⁺ selectivity in ZIFs for FCDI applications. Among the three ZIFs tested, ZIF-8-Br exhibits the highest Li⁺/Na⁺ selectivity in both simulations and experiments.

Accessible and low-cost point-of-use water treatment technology have significant potential to mitigate the risk to public health, particularly in areas with limited resources and in disaster scenarios. Natural cotton fibers functionalized with water-soluble proteins from Moringa oleifera seeds (MO-cotton filter) are a promising technology that exhibits high water permeability and effective removal of various contaminants.. Here, we demonstrated the performance of MO-cotton filters under practically relevant conditions to remove mammalian virus spiked in groundwater. Specifically, MO-cotton filters achieved >3.2-log₁₀ reduction at a superficial velocity of 0.7 m/h of two mammalian viruses, Tulane virus (TV, Caliciviridae, nonenveloped virus) and Transmissible gastroenteritis virus (TGEV, Coronaviridae, enveloped virus), which are representative of a significant portion of waterborne illnesses. We further evaluated the risk of virus particles detached due to shear forces by testing their infectivity and found that the viruses accumulated on the MO-cotton filters pose a minimal risk of contaminating the drinking water source. These findings support that the MO-cotton filter can serve as a point-of-use water purification technology, effectively reducing viruses to a safe drinking water level.

A novel E-peroxone process with tandem flow-through (TFT) configuration was developed in this work, and its efficacy was verified via the degradation of recalcitrant compounds, i.e., dyes and poly(vinyl alcohol) (PVA). The gas diffusion electrode (GDE) made of carbon fiber was employed as the cathode, while the anode of ruthenium–iridium acted as a dimensionally stable anode (DSA). The system achieved oxygen self-sufficiency through an innovative oxygen transfer mode, avoiding the need for an additional oxygen supply. The electrodes with TFT configuration ensured high utilization efficiency of ozone as the peroxone reaction occurred continuously in two adjacent chambers. H₂O₂ yield efficiency was compared between single and TFT E-peroxone processes under various conditions, including flow rates, current densities, and pH values. Under optimal H₂O₂ production conditions, the TFT E-peroxone process could remove 85.5% of dyes and 73.4% of PVA with single-pass, respectively. Electron paramagnetic resonance (EPR) tests and quenching experiments revealed that hydroxyl radicals (^•OH) and carbon radicals are the primary active species. Hydroxyl radicals played a major role in the single and TFT E-peroxone processes. This study demonstrates that the TFT E-peroxone process holds great promise as an advanced technology for efficient wastewater treatment.

Taking advantage of the complementary chemistries of the cooling blowdown water (BDW) and produced water (PW) from shale gas production, this pilot study evaluated their co-treatment feasibility to generate useful products while reducing treatment footprints. The process includes the mixing of BDW and PW, chemical softening, activated carbon (AC) filtration, and reverse osmosis (RO). The results showed that a simple mixing of BDW and PW (BDW/PW = 5) readily removed 98% of barium and 85% of sulfate and generated a high-density (4.1 g/cm³) barite-dominant solid with a yield of 1.92 kg/m³ mixed water. Softening using sodium carbonate and sodium hydroxide removed >95% scale forming divalent ions, and the AC filtration resulted in ∼90% total organic carbon removal. RO treatment of the AC effluent achieved ∼60% water recovery. Compared to BDW and PW treated separately, the co-treatment process resulted in a ∼70% chemical saving. The RO concentrate had high enough TDS (77 g/L) suitable for thermal evaporation to generate commercial-grade 10-lb brine. An initial technoeconomic analysis of a co-treatment scenario using a thermoelectric powerplant in West Virginia shows cost saving potential and revenue generation. This study demonstrates the potential of the co-treatment method as a useful tool for sustainable regional water management.

Co-management of cooling blowdown water and produced water offers opportunities of critical mineral and low-salinity water recovery.

Wastewater-derived phosphate contributes to eutrophication if the phosphate is not efficiently removed before it is discharged to surface waters. In the Florida Keys (USA), shallow injection of treated wastewater into saline limestone aquifers is a common mode of wastewater disposal. We assessed the possibility of efficient and permanent phosphate removal following injection at a wastewater treatment facility in Marathon, Florida. The concentrations of nutrients, dissolved ions, and anthropogenic compounds in groundwater and nearshore waters were monitored over two years, as was the progression of a patch of fluorescent dye emplaced by the wastewater injection well. The density contrast between the wastewater effluent and saline groundwater caused the effluent plume to buoy to the shallow subsurface near the injection well. Soluble reactive phosphorus (SRP) and sucralose were both detected in nearshore waters, indicating incomplete removal of contaminants. However, ∼75% of the SRP is removed from the plume in the first 10 days of transit by adsorption followed by a slower removal mechanism, bringing the P removal efficiency above 90%. A positive relationship between excess calcium and phosphate removal efficiency, together with high levels of calcium phosphate mineral supersaturation, supports calcite dissolution followed by calcium phosphate mineralization as this slower removal process.

Phosphate is efficiently removed from saline groundwater after injection of treated wastewater effluent by adsorption and calcium phosphate mineralization.