ACS ES&T water最新文献

Enhanced biological phosphorus (P) removal (EBPR) with return activated sludge (RAS) fermentation (S2EBPR) is a recent EBPR innovation suggested to achieve more stable and efficient P removal. However, consensus around these benefits and the mechanisms of S2EBPR is still developing. To further this understanding, three pilot sequencing batch reactors treating real domestic wastewater were operated as S2EBPR or conventional EBPR, with or without external carbon addition, and as S2EBPR with or without the anaerobic phase. Findings include the following: (1) S2EBPR showed a small P removal improvement over conventional EBPR; (2) S2EBPR performed substantially better with a small dose of external carbon added, while conventional EBPR did not, but microbial community stability was increased in both; (3) when external carbon to S2EBPR was stopped, high P removal continued for two solids retention times; (4) the measured fermentation yield suggested a larger benefit to S2EBPR P removal than was observed; (5) S2EBPR without the anaerobic phase did not achieve good P removal; and (6) although microbial community trends were similar, S2EBPR enriched more metabolically flexible polyphosphate accumulating organisms than conventional EBPR, importantly, Candidatus Phosphoribacter. Overall, RAS fermentation was beneficial to EBPR performance and stability with external carbon addition but minimally without.

Groundwater denitrification studies require the careful quantification of excess N₂ to determine that nitrate reduction has taken place. The measurement of corresponding noble gases Ne and Ar quantifies excess air N₂ and in situ degassing. We compare, for the first time, measurement results from a high-precision quadrupole mass spectrometer (QMS) with a low-cost PlasmaDetek (plasma emission detector) GC add-on capable of analyzing all three gases (N₂, Ne, Ar) from a single sample to obtain reliable data for denitrification calculations. Both methods can be used to accurately measure N₂, Ne, and Ar concentrations that are reproducible and overlap within 2σ analytical uncertainty. Moreover, we discuss different groundwater headspace gas collection methods and show that Giggenbach bottles, while limited when storing samples for long-time periods (months or more), are reliable over shorter storage periods (up to 2 or 3 weeks), compared to cold-pressed copper tube collection methods, which are deemed stable over long timeframes (years). This novel plasma detector method will enable laboratories that do not have state-of-the-art noble gas facilities to undertake reliable measurement of dissolved groundwater gases (N₂, Ne, and Ar) for groundwater denitrification studies, understand the implications of natural subsurface nitrate attenuation, and improve catchment nitrate budgets.

Natural hazards significantly impact drinking water availability and reliability, posing challenges in accessing sufficient quality and quantity. Understanding the connection between water access and perceptions of psychological resilience (defined as how individuals bounce back after facing a major trauma) can clarify its role in well-being postdisaster. This study surveyed 208 older adults in Puerto Rico (May–July 2021), aged 64–104 years, 65% of whom were female, to explore this linkage following Hurricane Maria. Results show a strong preference for bottled water with 86% of participants using it as a drinking source. Municipal tap water is the second most preferred at 71%, while well water is the least favored, used by less than 4%. A gender-specific effect was found in the association between municipal tap water consumption and psychological resilience, where municipal tap water consumption was associated with higher psychological resilience only among women. The findings suggest that although bottled water is the preferred choice, municipal tap water use is positively associated with psychological resilience among women postdisaster. Research is needed to replicate these findings to attempt to determine their consistency in other similar contexts and identify underlying reasons and future implications for disaster response and preparedness.

Sustainable waste management is the recycling, reusing, and recovery of wastes from natural sources. This research studied the conversion of Pinus sylvestris residues into sustainable biochars with improved properties for the adsorption of Co(II) and Ni(II) with further usage of spent biochars in the removal of carbamazepine. The biochars possessed high surface areas and abundant chemical composition with equilibrium adsorption capacities of 0.38 mmol/g for Co(II) and 0.48 mmol/g for Ni(II), forming cobalt phosphate and nickel hydroxide on the biochar surface. The laden biochars efficiently removed carbamazepine through adsorption and under UV light, following a first-order kinetic model with rate constants ranging from 0.0031 to 0.0042 min^–1 and achieving an efficiency of over 80%. The complex interaction mechanisms were responsible for the reduction of the carbamazepine concentration in the studied systems. This research demonstrates that waste wood raw materials can be used as synergistic multifunctional materials.

Streams are the primary conduits through which microplastics are transported from land to sea. Attributes of the plastic particles and of the streams are both likely to influence how microplastic moves, but there are few empirical studies of microplastic transport dynamics in real systems. We adopted the spiralling technique commonly used to measure nutrient cycling in streams to quantify transport distances and deposition velocities of microplastics in streams with varying geomorphological structure and level of human modification. We conducted pulse releases of trace amounts of three size classes of five different polymers spanning a density gradient in 15 streams. The streams were typical of the range of human modification in urban environments, from seminatural to highly modified. Transport distances of microplastic ranged from <1 to 111 m, with distances declining with particle size. Neutrally buoyant polymers had the longest transport distances and lowest deposition velocities. Streams that had been modified into concrete channels were the most effective in transporting microplastics downstream, as indicated by relatively low deposition velocities and long transport distances of microplastics. Our results suggest that the movement of microplastic pollution in streams depends on the physical characteristics of the stream more than on plastic properties.

The compounds generated during wastewater treatment processes might increase the complexity and chemical risk assessment of wastewater-derived dissolved organic matter (DOM) released into receiving water. This study applied Fourier transform ion cyclotron resonance mass spectrometry to investigate the dynamic changes in wastewater composition at the molecular level in a full-scale municipal wastewater treatment plant (WWTP). Approximately 63.1% of the detected molecules in the effluent were derived from the influent. N/S-containing molecules were more effectively removed than CHO molecules in the studied WWTP. The dealkylation and oxygen addition reactions of N-containing molecules, along with the predominant N-addition reactions of removed molecules observed in anaerobic and oxic tanks, contributed to the higher N/C_wa in the effluent than in the influent. However, the S-containing molecules could be effectively removed via S-loss reactions in the anoxic/anaerobic/oxic (inverted A/A/O) processes. Dealkylation and oxygen addition reactions were found to be the predominant reaction types in all tanks of the inverted A/A/O processes. More oxidized molecules with higher aromaticity and unsaturation degree were observed in the effluent than in the influent. Our findings provide a comprehensive view of the transformation of wastewater DOM in a full-scale WWTP and offer valuable insights into effluent water quality.

This study tried to reveal how the implementation and cancellation of the dynamic zero-COVID policy could affect the development of the epidemic through wastewater surveillance of SARS-CoV-2 in Beijing during its first COVID-19 surge. A total of 443 24 h composite wastewater samples were taken from seven manholes and 10 wastewater treatment plants immediately on December 7, 2022, when the new COVID-19 policy was implemented, for the detection of SARS-CoV-2. The results showed that the first COVID-19 surge in Beijing was characterized by a rapid outbreak, short duration (one month), and extremely high infection rate (92.8%). Wastewater tiling amplicon sequencing showed that the main subvariant for this surge was BF.7.14 (65%), which has never caused an outbreak in other countries in the world. The variant BF.7.14 appeared in Beijing on August 15, 2022, as an imported case and then managed to retain and become a dominant variant as the strict dynamic zero policy had blocked the entry of other more infectious SARS-CoV-2 variants. This is the first study to capture the unique picture of the epidemic development in Beijing during its first COVID-19 surge, demonstrating that the strict dynamic zero-COVID strategy could shape the infection patterns greatly.

Though diatoms as agents to remove silica pollutants have already been tested, the factors governing the photobiological process remain unexplored. The current process was developed to optimize various combinations of abiotic factors like pH (5, 6, 7, 8, and 9), mixing conditions (aeration, magnetic stirrer, and shaking-induced mixing), and light wavelength (red: 665–630 nm, blue: 465–430 nm, and white: 665–420 nm) for silica removal using diatom Navicula sp. from WC media. A combination of pH 7 and magnetic stirrer mixing (80–100 rpm) gave the best silica removal at 11.93 ± 0.15 mg L^–1d^–1. This optimized process with blue wavelength light increased the silica removal rate to 14.43 ± 0.37 mg L^–1d^–1 and biomass productivity to 95.15 ± 1.34 mg L^–1d^–1. Further, bioremediation of cooling tower blowdown water was tested under optimized and unoptimized conditions. A silica removal rate of 13.90 ± 0.26 mg L^–1d^–1 was achieved under optimized conditions, 3.69-fold greater than the unoptimized conditions (3.77 ± 0.42 mg L^–1d^–1). Additionally, this process removed >99% of total dissolved phosphate (3.05 ± 0.10 mg L^–1d^–1), nitrate nitrogen (12.27 ± 0.49 mg L^–1d^–1), and 54.27% chemical oxygen demand. Such optimization of abiotic factors using diatoms helps in achieving green silica-rich wastewater bioremediation.

Volcanic eruptions transport substantial amounts of sediment into river systems. It damages irrigation structures that depend on the nearby river for water delivery, reducing the conveyance efficiency. This study aims to propose an efficient approach for the management of sand traps as the main sediment barriers in irrigation networks within the Progo-Opak-Serang (POS) Volcanic Basin. It is accomplished by a measurable approach: a mathematical framework executed with the Hydrologic Engineering Center’s River Analysis System (HEC-RAS). This study focuses on selected sand traps: Badran, Blawong, and Pengasih. The results show that the calibrated and validated Manning’s coefficients of Badran, Blawong, and Pengasih Sand Traps are 0.014, 0.020, and 0.025, respectively. The combination of Thomas as a sorting method, Rubey as a fall velocity method, and Laursen as a transport function can represent the transport parameters of the sand traps within the POS Basin. The recommended flushing discharge and duration for Badran, Blawong, and Pengasih Sand Traps are 4, 4.4, and 1.9 m³/s and 150, 50, and 45 min, respectively, while the flushing frequency is 4, 3, and 3 times a year. The existing sand trap performance in Badran is less effective, while that of Blawong and Pengasih is less efficient. This study assists in improving food production and security by promoting sustainable irrigation systems.

Proper irrigation management facilitates the distribution and allocation of water to agricultural land, increasing production and food security.