Water Systems Research Articles

Reparameterization of the mW model to accurately predict the experimental phase diagram of methane hydrate.

Due to their high computational efficiency, the coarse-grained water models are of particular importance for practical molecular simulations of gas hydrates. In these models, the mW model is successfully used to study many thermodynamics and dynamics of methane hydrate. Yet, despite several decades of intense research, the mW model is still found to overestimate the melting temperature of methane hydrate. We here employ the minimum mean squared error estimation to revisit the key parameter of the mW model, which determines the strength of the tetrahedral angle of the water system. Relying on the free energy calculations, we first estimate the chemical potentials of water in the liquid phase for temperatures at which methane hydrate forms. We then turn to the mean squared error to describe the chemical potential deviation between the mW model and the TIP4P/ice model (the latter could reproduce the experimental phase diagram of methane hydrate). By minimizing the mean squared error, we finally have an optimized parameter for the mW model. In this part, we also discuss the pressure effect on such reparameterization procedure. Moreover, relying on the direct coexistence method, the melting temperature determined using the reparameterized mW model is found to be consistent with the experimental data. This strategy provides a means to improve the coarse-grained model to match the experimental observations for temperatures in the range of interest.

Characteristics of dissolved organic matter in water bodies during the dry season in the Huainan section of the Huaihe River Basin in Northern Anhui Province, China

This study investigated the spatial heterogeneity of dissolved organic matter (DOM) composition and characteristics in the central reaches of the Huaihe River Basin. The dry season DOM content and composition of three river bodies (the main stream of Huaihe River, the Huaihe tributaries and agricultural drainage ditches) in the Huaihe River Basin were studied using UV-Vis and three-dimensional fluorescence spectroscopy combined with parallel factor analysis (EEMs-PARAFAC). The degree of DOM humification and the relative molecular weight of tributaries and agricultural drainage ditches were significantly higher than those of the main stream (p < 0.01), and regarding the autogenetic characteristics of the three types of water bodies the tributaries and drainage ditches were more strongly affected by exogenous interference than the main stream. Three kinds of chemical components were determined by PARAFAC mode(C1:terrsstrial humus-like;C2:tryptophan-like;C3:protein-like), protein-like components were the main fluorescent components in DOM during the dry season, the proportion of different water systems exceeds 50%. Principal component analysis (PCA) showed that the fluorescence intensity of humus was closely related to the TP(Total phosphorus) concentration in the Huainan section water body of the Huaihe River Basin during the dry season. The absolute principal component-multiple linear regression model showed that the contribution of water nutrition to the C2 and C3 of protein-like fluorescent components was greater, while exogenous interference had a greater effect on the TP physicochemical index.

Reimagining public water: an intergenerational exploration of paradigms for future system design

ABSTRACT Due to the life-span of infrastructure, the complexity of components and the tendency of institutional structures to reproduce themselves, infrastructural systems as a whole are seldom reimagined. In addition, strategic thinking about possible system innovations is mainly done by the generations with extensive work experience. This whilst challenges such as climate change trigger the need for system innovation and are inherently intergenerational. This paper examines a method for “intergenerational reimagination”, facilitating reflexive learning within a generationally diverse subgroup of actors. This was done to explore paradigms for future system design. Building on the Advocacy Coalition Framework, descriptive, normative and explorative steps are developed. These steps include an intergenerational dialogue and carefully designed workshops, involving both young and senior professionals. The methodology was applied to reimagine the Dutch public water system, a design process which involved over 50 young professionals and resulted in three reimaginations. This process shows the potential for intergenerational development of possible paradigms for future system design. Moreover, throughout the process, policy-oriented learning was given substance. Finally, the study provided young professionals with a means to join strategic thinking at the semi-public level of water companies; a potential source of inspiration for other sectors and issues.

Features of Providing Air Temperature and Humidity Parameters in the Engine Room Working Area at Sewage Pumping Stations

Statement of the problem. There is an important task for engineers to improve the working conditions of workers in industrial facilities. The waste water system includes a large number of structures with different temperature and humidity microclimate characteristics. The possibility has been discussed to improve these characteristics by redistributing air flows in the engine room of a city sewage pumping station with PLI panel. Results. There are the results of the temperature and humidity microclimate parameters research in the working area of the engine room at a high-voltage sewage pumping station which is located in Moscow. The author has proved the possibility of use the cooled air from the machine room lower level in a high-voltage pumping station at the machine room main working area. It has been described the calculation features of the heat transfer coefficients in the proposed model for local ventilation at the main technological working area. It has been described the results of temperature and humidity parameters instrumental study in the main working area and the lower level. Conclusion. Thelocal ventilation systems could be used for the working area, where an employee performs repair work of the main technical equipment in a sewage pumping station. The balanced mathematical thermal model includes PLI panel’s potential location.

Water safety planning application for aesthetic quality of drinking water

ABSTRACT The World Health Organization considers water quality aesthetic parameters affecting taste, odor, and appearance, as factors to be monitored to determine the overall safety of water. Water safety plans (WSPs) can be used by utilities to proactively identify aesthetic hazards, rank them by likelihood of occurrence and consequence to the utility, generate risk scores, and provide direction on how to monitor, mitigate, and verify that controls are in place. The City of Wichita Falls Public Water System (CWF PWS) used the water safety planning approach to outline how aesthetics may negatively affect the system from source water, in-plant processes, and into the distribution system. By proactively identifying these hazards and outlining what to do using a WSP, the utility has put measures in place to ensure that aesthetically acceptable water is delivered to their customers. This article outlines the water safety planning process for water quality aesthetics and how the CWF PWS developed and implemented its WSP.

Degradation of enrofloxacin by Fe0 activated PDS.

In this paper, the effect of zero-valent iron (Fe0) activated persulfate (PDS) on the removal of enrofloxacin (ENR) was investigated, and the effect and mechanism were analyzed by exploring the effects of Fe0 concentration, PDS concentration, pH, and the influence of anion and aqueous matrix on the removal of ENR by the Fe0/PDS system. The results showed that when [ENR] = 20 µmol/L, [Fe0] = 0.15g/L, [PDS] = 0.4 mmol/L, the removal rate of ENR was 85.3% at 90min, the mainradicals were HO•, SO4•- and O2•-. At the same time, the system had a good mineralization effect (TOC removal rate > 40%), in addition, the system did not show obvious toxicity to soil microorganisms after the reaction, furthermore the Fe0/PDS system had a good removal effect on ENR in a wide pH range (4 ≤ pH ≤ 10). There is basically no difference in the removal rate of Fe0/PDS system in ultrapure water and river water.The results of this experiment could provide a reference for the removal of antibiotics based on advanced oxidation techniques based on SO4•-.

Evaluation of SDGSAT-1 MII data in total suspended matter estimation in clear to extremely turbid rivers

ABSTRACT The Multispectral Imager (MII) onboard the newly launched SDGSAT-1 holds significant promise for monitoring and understanding variations in water quality within nearshore water systems, with an impressive spatial resolution of 10 m, seven spectral bands in the visible and near-infrared domain and a wide swath of 300 km. This paper evaluates the MII data in estimating the concentration of total suspended matter (TSM) in rivers and estuaries from clear to extremely turbid conditions. For atmospheric correction, the ACOLITE model showed superior performance compared to the FLAASH and 6SV, with average unbiased relative error (AURE) ranging from 11.8% to 26.4% in the four visible bands of MII. Through comparison, a TSM model based on the visible band ratio (i.e., Rrs (660)/Rrs (560)) was proposed to ensure the application of MII data in both clear and turbid waters, with an overall AURE of 40.9%. The model was then applied to map the TSM variations in the Hai and Liao Rivers in northern China using the MII data, where reliable spatial and temporal patterns were observed. The study concludes by discussing the applicability of MII data in water quality mapping in nearshore waters, along with key considerations such as model applicability, atmospheric correction, and land adjacency.

Water Quality Analysis of a 300 Mvar Large-Scale Dual Internal Water Cooling Synchronous Condenser External Cooling System and Exploration of Optimal Water Treatment Agent Dosage at Different Temperatures

The external cooling water system of a 300 Mvar dual internal water cooling synchronous condenser at a certain ultra-high voltage converter station continued to exhibit significant scaling and corrosion, even with regular addition of scale and corrosion inhibitors. To solve this problem, the external cooling water of the synchronous condenser was sampled and tested periodically, with the main test items including conductivity, pH value, turbidity, hardness, alkalinity, and other water quality parameters directly related to corrosion and scaling. The trends of these parameters over time were also analyzed. The results showed that as the operation time increased, the cooling water became concentrated during multiple circulation cycles, and the various dissolved or suspended substances underwent a certain degree of enrichment. However, the addition of scale and corrosion inhibitors did not dynamically adjust according to the changes in water quality, and there was always an excessive dosage. Thus, using the external cooling water as the experimental sample, static scale inhibition tests and rotating coupon corrosion tests were conducted to evaluate the scale and corrosion inhibition performance of the commercial AS-582 scale and corrosion inhibitor used at this ultra-high voltage converter station under different conditions. Considering the more obvious corrosive tendency of this water sample, the focus was on testing its corrosion inhibition performance. When the dosage was 600 ppm, the scale inhibition effect was optimal, with an inhibition rate of 92.15%. The corrosion inhibition effect of this scale and the corrosion inhibitor were significantly related to water temperature. At 25 °C, when the dosage was 500 ppm, the corrosion inhibition effect was optimal, with an inhibition rate of 86.79%. However, when the temperature increased to 40 °C, the corrosion inhibition effect under each dosage was significantly worse, unable to meet the requirements, and the use of other corrosion inhibitors in combination was necessary. This work will provide a reference for the scientific use of scale and corrosion inhibitors.

Existence of Thermotolerant and Salt-Loving Diarrheagenic Vibrio alginolyticus in Non-Saline Potable Water System: A Novel Finding from India.

We present a novel report of abundance of halophilic Vibrio alginolyticus with thermotolerant and enterotoxigenic characteristics from community water system of an inland-focus of India causing diarrheal outbreak as an index pathogen. Though, Vibrio alginolyticus causing diarrhea after exposure to marine water and consumption of seafood was reported globally, its existence in non-saline drinking-water sources with pathogenic viability was unknown. A 'matched-pair-case-control' study identified the primary source of V. alginolyticus infection as 'tap-water' distributed by the municipality, used for drinking (MOR: 8.33; 95% CI 2.51-27.6) and household chores (MOR: 3.75; 95% CI 1.24-11.3). Cardinal toxin gene 'tdh' and other pathogenicity markers viz.tlh, vppC, toxR, VPI, T3SS1 and sxt were detected in V. alginolyticus isolates. Expression potential of the hemolytic genes are demonstrated by hemolysis assay and transcriptome analysis. Altogether 30.55% of isolates exhibited strong hemolytic potential in vitro. RT-PCR revealed uninterrupted virulence gene expression in outbreak strains under heat stress. Surprisingly, ~ 100% of V. alginolyticus from the outbreak focus were sensitive/partially sensitive to all group of antibiotics except β-lactums, carbapenem and quinolones. High drug-sensitivity suggested lack of previous human gut exposure and indicated a fresh dissemination from the environmental niche to the community domain. The maximum likelihood phylogeny depicted multiple clades in V. alginolyticus strains from Pan India sources. Isolated outbreak strains shared common ancestry with the strains from nearby riverine system, a source of 'drinking water' supplied to the affected community, confirming its environmental origin. V. alginolyticus, traditionally a fish-pathogen, is steadily gaining an emerging epidemiological relevance alongside other waterborne diarrheagenic bacteria and its 'thermotolerant' attribute poses additional threat under the canvas of climate change.

Prediction of Sediment Transport and Deposition in the Stone Buddha Temple Reservoir Based on HD and ST Bidirectional Coupling Model

Reservoirs deliver vital ecological services, including water storage and drainage. However, these functions are increasingly compromised by the dual pressures of climate change and human activities. Among the most pressing concerns is reservoir sedimentation, highlighting the urgency of investigating hydrodynamic sediment scouring. This study focuses on the plain reservoirs of Liaoning Province, using the Shifo Temple Reservoir as a case study. An optimized sediment scouring scheme was developed based on the reservoir’s hydrodynamic characteristics to improve water and sediment management. A coupled hydrodynamic and sediment transport (ST) model was constructed to simulate runoff dynamics and sediment distribution within the Liao he River Basin, while the MIKE21 model was applied to simulate the interaction between the hydrodynamics and sediment transport. The study analyzed groundwater dynamics across different runoff scenarios, seasons, and representative years, offering a scientific foundation for optimizing water and sediment allocation strategies. The results demonstrated a strong correlation between simulated and observed data during validation, confirming the accuracy of the hydrodynamic simulations. Utilizing the coupled HD and ST modules, the study proposed a sediment transfer scheme. The analysis revealed that flow rates between 165 and 190 m3/s significantly enhance sediment scouring in the long term (2029–2039) compared to the short term (2024–2029), effectively reducing sedimentation, minimizing deposition length, and lowering silt removal costs. The findings offer critical insights for predicting reservoir evolution and conducting risk assessments, thereby contributing to the sustainable management and ecological restoration of water systems in Liaoning Province.

Pseudosteady shock refractions over an air–water interface

Shock refraction in a gas–liquid interface is ubiquitous in nature and engineering. This study investigates the shock refraction phenomena in air–water interfaces for various inclination angles. The interface inclination angles are achieved using a tiltable vertical shock tube. The time-resolved schlieren images are compared with numerical simulations performed using the BlastFoam solver in the OpenFOAM software. The stiffened gas equation of state is used to model water in the simulations. The shock polar analysis using modified shock relations for a stiffened gas is used to elucidate the refraction patterns. A regular refraction pattern with a reflected shock wave and a bound precursor refraction with a regular reflection are observed experimentally for the first time in an air–water system. Further, a new free precursor refraction pattern with a Mach reflection is observed. The transition criteria and the corresponding boundaries for each refraction pattern are demarcated in the ( $M_S, \theta _w^c$ )-plane. The refraction sequence and the range for various incident shock strength regimes are also identified.

Novel hybrid coating material with triple distinct healing bond for fat oil and grease deposition control in the sewer system

Hybrid materials with distinct self-healing bonds are a prominent category of materials, demanding in various modern applications. Developing self-healable hybrid materials with desired self-healing properties at ambient conditions is highly desirable and challenging. Herein, we developed a novel zinc (II)–dimethylglyoxime–urethane-complex-based polyurethane elastomer (Zn-polyurethane hybrid material) with synergetic triple dynamic bonds, which exhibits spontaneous self-healing properties at 30 °C. Moreover, this material shows excellent thermal stability up to approximately 850 °C and is highly stable in water systems. This hybrid material has potential applications in water systems; in this study, we characterized it for fat, oil and grease (FOG) deposition management in sewer systems by applying it as a coating on concrete blocks. The findings indicate that following a 30-day leaching test conducted under controlled pH conditions on uncoated and Zn-polyurethane-coated concrete blocks, a reduction of over 80 % in calcium release was observed in the coated block compared to the uncoated concrete block. Additionally, in FOG deposit formation tests conducted on uncoated and coated concrete blocks for 30 days, a reduction of over 30 % in FOG deposit formation was noted in the coated sample.

Building the social. A query into the societal impact of the Pompeian water supply

This study explores the importance of the means of ensuring water supply in the formation of the architectural profile and basic social organization of Pompeii. It sees the city’s domestic water supply, for over two centuries ensured through rainwater-harvesting areas, basins and cisterns situated mainly in and below the many atria, as a stabilizing factor of both cityscape and household. Through the introduction of the city aqueduct in the 1st century AD and the creation of a generous network of public fountains this situation changes and the need to maintain the traditional organization of the “houseful”, comprising enlarged family, slaves and dependents of various kind including shopkeepers, is lessened; the physical proximity between those of different status renegotiated. This development, witnessed in adaptations of the architecture, can be followed through close study of the standing structures in Insula V 1. The hallmarks are the creation of upperfloor living quarters seemingly independent from the life of the large households of the atrium houses, and in parallel the introduction of private water lines from the city aqueduct. The remodelling that resulted in the creation of the double-atrium house of Caecilius Iucundus is focal to the discussion since it offers a coeval chronological fix point in the AD 40s for both remodelling and obtention of piped water. Given that the change in the domestic architecture observed was merely in its embryonic state in AD 79, the tenability to attribute a lower dating than that traditionnaly attributed not just to the private lines, but to the city’s distribution system of public aqueduct water as well, is reasoned. The particularities of Pompeii’s geomorphological situation and political status and how they impacted the discussed change in social relationships are also raised.

Integrated renewable energy systems as the basis for sustainable development of energy, water and environment systems

Integrated renewable energy systems as the basis for sustainable development of energy, water and environment systems

The global burden of enteric fever, 2017–2021: a systematic analysis from the global burden of disease study 2021

Enteric fever is a major public health challenge in developing countries. We conducted a systematic analysis from the Global Burden of Diseases 2021 Study to provide updated estimates of enteric fever's burden. We presented estimates for incident cases and deaths, age-standardized incidence and mortality rates, years of life lost (YLLs), and case-fatality rates spanning the study period of 2017-2021, stratified by region, country, socio-demographic index (SDI), and age group. Random-effects Poisson regression for longitudinal data was used to estimate the association between SDI and case-fatality rates, adjusting for antimicrobial resistance patterns. In 2021, there were 9.3 million global cases of enteric fever (95% uncertainty interval: 7.3-11.9) and 107.5 thousand deaths (56.1-180.8). The age-standardized incidence rate decreased from 152/100,000 person-years (118-195) in 2017 to 128/100,000 person-years (100-163) in 2021, and the mortality rate decreased from 1.87/100,000 person-years (0.95-3.18) to 1.50/100,000 person-years (0.78-2.54). There were wide geographical differences, with South Asia contributing the most cases and deaths. Age-standardized incidence exceeded the threshold for "high burden" of enteric fever (100/100,000 person-years) in 23 countries in2021.Children under five accounted for 40% of deaths and 47% of YLLs, with incidence and mortality peaking during the second year. Case-fatality was highest in low SDI countries and showed a global trend toward reduction, except among children aged 1-4 years. After adjusting for the prevalence of multidrug resistance, fluoroquinolone non-susceptibility, and third-generation cephalosporin resistance, a higher SDI was associated with a lower case-fatality rate, with a 1.1% (0.7-1.7) reduction for each percentage point increase in SDI. Despite notable improvements, several countries still showed a high burden of enteric fever, which remains a significant global health concern, especially among children under five. Although enhancing water and sanitation systems is crucial, the most significant reductions in the global disease burden are likely to be achieved through broader vaccine coverage. This includes the use of typhoid conjugate vaccines, which are effective in infants and young children and offer extended protection, along with improved data collection and surveillance to guide vaccine distribution efforts across high-incidence areas. This work was partially supported by "Ricerca Corrente" funding from Italian Ministry of Health to IRCCSHumanitas Research Hospital.

Evaluating the impact of residual low chlorine concentration on phytoplankton communities by flow cytometry

Chlorination is widely used to prevent biological fouling in power station cooling water systems. It may impact non-target organisms both within the cooling system and after discharge (primary and secondary entrainment). However, there is a lack of data on the impacts of the low chlorine concentrations that occur in the discharged plume on marine phytoplankton community structure and function.We examine the impacts on natural phytoplankton communities of single and multiple exposures to chlorination at concentrations between 0.02 and 0.1 mg/L total residual oxidants (TRO). Low-level chlorination causes limited changes in diversity and has no impact on total biomass. However, changes in size structure and functional diversity quantified using flow cytometry do show a reduction in smaller cells, particularly eukaryote picophytoplankton.These impacts are not detectable using chlorophyll a concentration alone, so flow cytometry provides important additional information over more standard ecotoxicological methods.The effects are likely to be localised in the vicinity of the discharges (mixing zone) where the environmental quality standard (EQS) of 10 μg/L for chlorine is exceeded, but impacts on coastal food webs and biogeochemical cycles should be further evaluated.

Preparation of PDMS permeation membrane by emulsion dilution method and its separation performance for aromatics

Natural aroma compounds are a kind of important food additive. Taking bis(2-ethylhexyl) sodium sulfosuccinate (AOT) as the surfactant, water-in-n-heptane emulsions were prepared. Then, the emulsions were adopted as the diluter to prepare polydimethylsiloxane (PDMS) pervaporation membranes using the emulsion templating method (ePDMS), of which the separation layer was controlled by the template action of emulsion drops. The ePDMS membranes were utilized to separate aroma compounds. Field-emission scanning electron microscope (FESEM) analysis revealed that the surface of the ePDMS membrane remained smooth, and white light interferometry confirmed the membrane’s surface smoothness. FESEM cross-sectional analysis exposed the voids left by the evaporation of the emulsion, rendering the separation layer of the ePDMS membrane more porous. Water contact angle measurements demonstrated the hydrophobicity of the ePDMS membrane, which is advantageous for the pervaporation of aromatic compounds. Fourier transform infrared spectrometry analysis confirmed the evaporation and separation of the emulsion, retaining the original chemical properties of the PDMS membrane. In an ethanol–water system, the permeation flux of ethanol in ePDMS membranes prepared with 1 emulsion (Vwater:Vn-heptane = 1:9; mass concentration of AOT of 1.0 mg/ml) is 90.6% higher than that in PDMS membranes, while the separation factor does not change obviously. The separation performance of ePDMS membranes for linalool in water was further studied. Results show that the permeation flux and separation factor of linalool in ePDMS composite membranes at 50 °C are 786 g m−2 h−1 and 17.69, which separately increase by 84.7% and 27.1% compared with those in PDMS membranes. This indicates that adding ethanol exerts a significant synergistic effect on the separation of linalool.

Modeling the health impact of wastewater contamination events in drinking water networks

Pathogen intrusion in drinking water systems can pose severe health risks. To better prepare in planning and responding to such events, computational models that capture the intrusion and health impact dynamics are needed. This study presents a novel benchmark testbed that integrates current knowledge on pathogen transport and fate in chlorinated systems and can assess infection risk from contamination events. The model considers organic matter degradation, chlorine decay mechanisms, pathogen inactivation kinetics, as well as stochastic water demands.We studied modeling of wastewater intrusion events that can occur anywhere within a chlorinated and non-chlorinated network. We applied the Quantitative Microbial Risk Assessment framework focusing on three pathogens: enterovirus, Campylobacter, and Cryptosporidium, and their respective dose-response models. Synthetic household-level water demand time series were used to model the individual water consumption timing and calculate the infection risk (exposure via ingestion).Model outcomes indicate that while chlorination aids mitigation, larger contaminations can still lead to infections due to chlorine resistance (for Cryptosporidium) and chlorine depletion at the contamination point. In our example scenarios, chlorine-susceptible pathogens infected of the downstream population, while chlorine-resistant ones infected the entire downstream population. Enterovirus infection risk is higher, despite the concentrations in the contamination source being lower, due to the lower susceptibility to chlorine than Campylobacter. In non-chlorinated networks, the modeled wastewater contamination events led to infection risk in the total population, depending on the contamination location. Hydraulic uncertainty had a limited influence on infection risk. Furthermore, Campylobacter’s infection risk is more sensitive to the initial concentration in the contamination source whereas enterovirus infection risk to the inactivation rate. The model further indicates that the time window for effective mitigation of the magnitude of a waterborne outbreak is short (within hours).

Precisely regulating ion convection to counteract electro-migration for H+–OH- separation with enabling efficient electrochemical water softening

Conventional electrochemical precipitation softening often suffers from the low utilization of OH– for hardness precipitation on the cathode surface in traditional undivided electrolytic cell. In this study, an asymmetric cathode was designed to confine the occurrence of H2 evolution reaction at its backside in an undivided electrolytic cell, where the electrodes were placed aslant at an angle of 5° to facilitate the upward motion of H2 bubbles and the water flowing distribution network was used to inhibit the circumfluence of water. This specific cell configuration successfully decoupled the ion convection and electro-migration behaviors, and regulated the convection behaviors of H+ and OH– to counteract their electro-migration behaviors. Specially, theoretical calculations revealed that the OH– convection rate (Vw,b = 0.033 ∼ 0.043 cm s−1) under the combined effects of H2 gas bubbling and water flowing-through cathode at current densities of 1 ∼ 15 mA cm−2 was larger than its electro-migration rate (Ve = 0.0062 ∼ 0.019 cm s−1), which effectively promoted the transport of OH– away from the cathode backside into the bulk solution opposite to the direction toward the anode side. The H+ electro-migration toward the cathode could be also offset by the convection mediated by water flowing-through anode. Thus, the H+–OH– neutralization reaction was effectively inhibited, favoring the hardness precipitation. Under the optimum condition, the developed cell showed a Ca hardness removal efficiency of 80.8 ± 1.18 % and a current efficiency of up to 73 % at an energy consumption of 2.67 ± 0.13 kWh kg−1 CaCO3, which were superior to most electrolytic systems with or without membranes. Generally, this study provides a precisely engineered electrodes configuration for energy-efficient electrochemical water softening in circulating cooling water system.

Water-based Silicalite-1 porous liquid facilitates adsorption and absorption for CH4 capture

As the key to open the Pandora’s box of gas efficient capture, water-based porous liquids have doubled the popular attention. Nevertheless, the synthesis of water-based porous liquids is a significant challenge due to the inherent limitation in the wettability of nanoporous hosts. In this work, Silicalite-1 was prepared by hydrothermal synthesis, based on which a water-based porous liquid of S-1-PL was successfully prepared, and CH4 capture in the porous liquid via adsorption-absorption synergistic approach was evaluated. It was demonstrated that S-1-PL exhibited excellent stability and flowability, with a pore opening ratio up to 90 %. CH4 capture capacity in S-1-PL with the solid content of 15 wt% was 0.57 mol/L, which was 2.6 times that in pure water system, demonstrating excellent CH4 physisorption performance. When the adsorption-absorption synergistic approach was employed, CH4 capture capacity increases to 1.88 mol/L with an increase by 229.8 %. In addition, a hydrate nano-promoter of −SO3-@PSNS was prepared to enhance hydration efficiency, which resulted in a notable enhancement in the hydration conversion rate, and it increases from 12.54 % to 61.99 % in the system of S-1-PL15wt%, giving rise to a significant increase in CH4 capture to 6.22 mol/L, which is 12.67 times that in the system of −SO3-@PSNS solution. These findings provide clear evidence for the first time on the exceptional adaptability of water-based porous liquid for the capture of CH4 by adsorption-absorption synergistic approach, offering a new strategy for the emission reduction of CH4.