ACS ES&T water最新文献

Pharmaceuticals and personal care products (PPCPs) are emerging pollutants in aquatic environments, posing significant ecological risks. Cyanobacteria, as primary producers in aquatic ecosystems, are crucial for ecosystem health. Understanding the toxicological effects and metabolic mechanisms of PPCPs in cyanobacteria is essential for evaluating environmental risks and bioremediation feasibility. This study reveals that while both sulfamethoxazole (SMX) and triclosan (TCS) inhibit algal growth by reducing photosynthetic pigment synthesis and activity, Synechocystis sp. PCC 6803 shows markedly different sensitivities to these compounds. The 72-h EC₅₀ values for TCS and SMX were 14.55 μg/L and 19.74 mg/L, respectively. Despite these differences, Synechocystis sp. PCC 6803 achieved removal rates of 89.58% for TCS and 87.60% for SMX. Biodegradation was the primary mechanism for both, but TCS removal also involved biological adsorption and bioaccumulation, mechanisms absent for the hydrophilic SMX. Metabolic pathway analysis identified glycosyltransferase-mediated reactions as key in TCS metabolism, while N4-hydroxylation-SMX (m/z 270) was a critical intermediate in SMX degradation. Notably, the sll1732 gene was found to play a pivotal role in SMX degradation. This research offers insights into the interactions between Synechocystis sp. PCC 6803 and these PPCPs, highlighting its potential for environmentally sustainable bioremediation.

The solar-driven multistage desalination (SMD), with its characteristics of a high vapor generation rate, has emerged as a green and effective solution to replenish the demand of freshwater. However, the integral design principle of a high-performance SMD system remains a challenge. Here, a design strategy to improve the water production performance of the SMD system through the synergistic effects of multifaceted structural optimizations is clarified. By constructing a thermal insulation chamber at the first stage to reduce convective heat loss and combining the evaporative cooling effect at the final stage to enhance thermal dissipation capability, the overall temperature gradient as the evaporation driving force of the SMD system is enhanced. Simultaneously, the vapor diffusion resistance is reduced by utilizing 3D printing technology to optimize the interstage air gap. An excellent water collection rate (WCR) of 2.71 kg m^–2 h^–1 is obtained through a 6-stage SMD device under one sun. Furthermore, the 6-stage device exhibits good practical application potential by achieving a substantial WCR of 12.28 kg m^–2 day^–1 in an actual outdoor deployment. The design strategy proposed in this work is expected to provide effective guidance for further structural optimization of the SMD system.

This study explores the use of asymmetric polarity reversal (PR) in continuous electrocoagulation (EC) for removing silica and hardness using Fe/Al hybrid electrodes. Asymmetric PR takes advantage of aluminum’s tendency to undergo cathodic dissolution by alternating a “forward” current with cheaper iron anodes and a shorter reverse current with aluminum as the anode, as iron cathodes are not prone to dissolution. Adjusting the polarity reversal time (PRT) varied the relative dosing of the Fe and Al coagulants. Silica removal exceeded 95% across all asymmetric PRTs at a fixed charge loading of 2000 C L^–1, with energy consumption between 1.44 and 1.93 kWh m^–3. Symmetric 10 min PRT achieved 90% Ca and 75% Mg removal, outperforming direct current (DC) EC. Both asymmetric PRTs of 10 min (Fe) and 30 s (Al) and a symmetric PRT of 10 min (Fe/Al) achieved high contaminant removal and relatively low treatment costs while using different amounts of Fe and Al. These configurations also lowered the cell voltage due to reduced fouling and passivation. This hybrid EC with asymmetric PR offers a novel, cost-effective method for adjusting the performance and optimizing the cost of wastewater treatment.

The eco-safety of plasticizer alternative di-isobutyl phthalate (DiBP) has received continued concerns owing to its large usage as a plasticizer and high detection frequency in environments. The concentrations of dibutyl phthalate (DBP) and DiBP in the surface waters ranged from ng/L to μg/L. However, the accurate ecological risk assessment of alternatives is limited by data on toxic effects and potencies. The interspecies correlation estimation (ICE) model combined with the species sensitivity distribution (SSD) model was used to assess the ecological risk of DBP and DiBP. The acute and reproductive predicted no-effect concentrations (PNECs) were derived as 0.05 mg/L and 1.23 μg/L for DBP and 0.16 mg/L and 0.51 μg/L for DiBP based on ICE-SSD models. Our results showed that acute risks (risk quotient (RQ) < 0.1) in mainland China waterbodies, except Hangzhou Bay, were acceptable. The risk quotients indicated that Yangtze River (RQ = 1.55 and 0.48), Hun River (RQ = 1.74 and 6.03), and Hangzhou Bay (RQ = 7.33 and 13.49) had relatively high ecological risk levels based on the reproductive PNECs of DBP and DiBP. Furthermore, the joint probability curves showed that the ecological risks in Hangzhou Bay needed further concern. Thus, the ICE-SSD model could effectively compensate for the lack of toxicity data in risk assessment.

Effective and energy-efficient wastewater disinfection is crucial for sustainable water management, especially in light of global water scarcity. This study introduces a novel computational fluid dynamics (CFD)-optimized Baffled Airlift Reactor (BALR) to address inefficiencies in ozonation-based disinfection. By integrating vertical and horizontal baffles, the BALR enhances gas–liquid interaction, increases ozone contact time, and minimizes dead zones, achieving a 99.62% total coliform removal efficiency and a 38% reduction in energy consumption (0.011 kWh·m^–3) compared to conventional systems. Beyond wastewater treatment, BALR can also be considered as an option for industrial applications, such as chemical processing and food safety, offering broad utility. Sensitivity analysis and scalability testing validate the design’s robustness and applicability to diverse settings. These findings establish a scalable, high-efficiency framework for advanced water treatment systems, laying the groundwork for the future integration of renewable energy sources into ozonation technologies.

Accurate identification and control of wastewater treatment processes are critical for the efficient use of water resources. Advances in online monitoring and computational capabilities have facilitated the integration of artificial intelligence (AI), particularly machine learning (ML), into wastewater treatment systems. This review analyzes 433 studies on ML applications in wastewater treatment from 2000 to 2022 using bibliometric methods, examining research trends, hotspots, and future directions. Since 2015, the field has experienced a significant surge in publications. The United States and Spain are notable for their long-standing contributions, while China, despite entering the field late in 2012, has emerged as the leading contributor in publication volume. Keyword analysis reveals “neural networks” and “artificial neural networks” as the most frequently applied ML techniques, alongside terms like “prediction”, “optimization”, “fault detection”, and “design”. Our comprehensive review further shows that ML applications in wastewater treatment primarily focus on feature identification, parameter prediction, anomaly detection, and optimized control with key application scenarios including systems, wastewater, waste gas, and sludge. As the demand for AI in wastewater treatment continues to grow, multimodel integration and in-depth development may become the focus of future research to address multiobjective challenges in wastewater treatment more effectively.

Nanoparticles (NPs) are present in the environment because of the widespread use of engineered nanomaterials and the breakdown of plastic waste. NPs can negatively impact human health, and water treatment plants lack treatment trains that are optimized for NP removal. Thus, there is a crucial need for a low-cost, effective NP removal technology. We fabricated a low-cost filter using diatomaceous earth (DE) and cationic proteins extracted from Moringa oleifera (MO) seeds. These filters achieve 4.9 log removal of a palladium-doped plastic NP and greater than 2.9 log removal of silver NPs and polystyrene latex particles. Moringa protein-functionalized filters can be utilized to remove NPs in a variety of applications such as for point-of-use drinking water treatment, washing machine effluent filtration, or municipal water treatment.

A building plumbing rig experiment simultaneously examined how water temperature (cold/hot lines), influent disinfectant residual (0–1 mg/L chloramine), flow rate (0.5–2.2 gpm), and water retention time (WRT) of 0–17-days impacted water quality at the point of use. In cold water lines with no disinfectant, WRT was a key driver of bacterial growth, with total cell counts (TCC) in the water increasing by up to 20× relative to influent water at 6.7-days WRT. A chloramine residual in cold influent water suppressed the maximum TCC by about 50%, even after the residual was no longer measurable. When the water heater set point was warm (40 °C) with minimal or 1 mg/L Cl₂ chloramine, the majority of microbial growth occurred in the tank (WRT = 3 days). However, at a heater set point of 60 °C with 1 mg/L as Cl_2, growth was completely repressed in the tank, shifting growth to the distal pipes. Legionella spp. gene copies measured in cold bulk water increased with WRT, but not flow velocity. In hot water biofilms, Legionella spp. gene copies were highest at low WRT and high flow velocities. Mycobacterium spp. gene copies in hot water biofilms escalated after chloramines were introduced and were positively correlated to water velocity.

An at-scale pipe rig revealed that the location of optimal growth niches for Legionella spp., Mycobacterium spp., and total bacteria is dependent on water age, water heater set point, and influent disinfectant level.

This paper takes the Fuyang River in the North China Plain as an example, utilizing an optimized phosphate oxygen isotope (δ¹⁸O_P) preprocessing method and extensively collecting watershed phosphorus (P) source and overlying water δ¹⁸O_P data. Under the premise of validating the application of δ¹⁸O_P, this study enhances the Bayesian mixing model priors using the end-member mixing model and iteratively corrects the total phosphate load to achieve quantitative identification of P sources at both the watershed and administrative division scales during the rainy season. It also summarizes a methodological framework for the application of δ¹⁸O_P in watersheds. The results show that the total phosphate load at the watershed scale amounted to 241.36 kg/d, with contributions from the tributary inflow, sediments, riparian soils, wastewater treatment plant (WWTP) effluents, and street dust, accounting for 38.8, 23.4, 17.3, 16.2, and 4.3%, respectively. Variations in P source contributions and loads across administrative divisions reflect regional economic and land-use diversity. P management strategies should adopt region-specific approaches, considering diverse land uses and their effects on P transport. This study demonstrates δ¹⁸O_P’s effectiveness in quantitatively identifying multiscale P sources and calculating phosphate loads during the rainy season, providing technical support for precise watershed phosphate load reduction.

Current wastewater treatment plants have not been designed to remove organic micropollutants (OMPs) that are now prevalent in surface waters. This desktop study investigates the Membrane Concentrate Recirculation to Activated Sludge (MCRAS) process, which enhances the removal of the OMP by combining conventional activated sludge treatment with membrane filtration and recirculation of the concentrate back to the activated sludge. The process limits the release of the OMP to the environment and offers an integrated approach for treating the concentrate. Four model OMPs (diclofenac, carbamazepine, ibuprofen, and triclosan) were studied using a mass balance model and literature data, comparing the performance of five membrane types (XLE, NF90, NF270, TFC-SR2, and dNF40). Four removal scenarios were identified based on biodegradation and membrane retention. Notably, with low biodegradation and high membrane retention, OMP removal can be significantly enhanced: diclofenac removal increased from 29 to 72% with an NF270 membrane and up to 97% with XLE or NF90 membranes. However, membrane use also leads to the accumulation of salts, as salts are not biodegradable. This highlights the need for a balance between the OMP and salt retention. Therefore, future membrane development should focus on improving the retention of the OMP while minimizing salt retention.

The Membrane Concentrate Recirculation to Activated Sludge (MCRAS) process enhances organic micropollutant (OMP) removal from wastewater while salts and OMPs may be accumulated in this process.