DSpace collection: 期刊論文

Sustainable beneficiation of high-ash Indian coal: phytochemical-facilitated demineralization and energy enhancement

title: Sustainable beneficiation of high-ash Indian coal: phytochemical-facilitated demineralization and energy enhancement abstract: Improving the quality of high-ash Indian coal remains a significant challenge for enhancing energy efficiency and reducing environmental impact. This study introduces a sustainable beneficiation approach utilizing aqueous stem extracts of Myristica malabarica as a green, plant-derived alternative to conventional chemical leaching agents. Phytochemical characterization confirmed the presence of polyphenols, flavonoids, and chalcones, compounds recognized for their potent chelating and surface-active properties. Bio-extract treatment effectively reduced coal ash content from 35.12% to 31.05%, representing a relative reduction of 11.6%. This demineralization led to significant enrichment in fixed carbon and a substantial increase in gross calorific value (GCV) from 4403 to 4958 kcal/kg. Structural analyses via XRD and FTIR indicated the partial degradation of key crystalline mineral phases, including quartz and kaolinite. SEM-EDS observations corroborated these findings, revealing notable surface decontamination and a significant decrease in the elemental concentrations of silicon and aluminum. These improvements are attributed to the synergistic effects of metal chelation and redox-mediated interactions between the phytochemical constituents and the coal mineral matrix.

An integrated iron electrolysis-electrooxidation for phosphorus recovery as ferric phosphate

title: An integrated iron electrolysis-electrooxidation for phosphorus recovery as ferric phosphate abstract: This study develops an integrated electrodissolution-electrooxidation (ED-EO) process for recovering phosphorus (P) as high-purity ferric phosphate (FePO4) from synthetic acidic phosphate-containing wastewater representative of industrial effluents from semiconductor manufacturing, fertilizer production, and lithium-ion battery-related industries. A sacrificial iron anode releases ferrous (Fe2+) via electro-dissolution (ED), while a Ti/RuO2-IrO2 anode generates in-situ reactive chlorine species (RCS) in the sodium chloride electrolyte to oxidize Fe2+ to ferric (Fe3+), enabling stoichiometric FePO4 precipitation without external oxidants. Process optimization demonstrated that controlled acidic conditions (pH 1.6–2.0), ED current densities of 2.55–7.60 mA/cm2, and Cl−:P molar ratio ≥ 1:1 achieved >99% phosphorus removal at Fe:P ≈ 1:1, with superior settleability (sludge volume index of 111 mL/g P). Iron generation aligned with Faraday's law initially, while prolonged operation at elevated current densities resulted in experimental Fe concentrations slightly exceeding theoretical predictions, suggesting the presence of parallel non-faradaic chemical dissolution pathways under acidic chloride conditions. Multi-technique characterization (XRD, SEM-EDS, and XPS) confirmed the formation of amorphous hydrated FePO4 that transformed into a crystalline, a high-purity FePO4 precursor material for potential lithium-ion battery applications upon calcination at 600 °C. Operational costs were primarily energy-driven and comparable to those of electrochemical vivianite production, while the higher-value FePO4 product (∼3.8 USD/kg) was produced. The reagent-free, single-compartment configuration enhances process controllability and scalability, offering a viable strategy for sustainable phosphorus recovery.

A Transformed Time Conformable-Type Slug Test Solution for Finite-Diameter Wells in Confined Aquifers: Verification, Identifiability, and Field Diagnostics

title: A Transformed Time Conformable-Type Slug Test Solution for Finite-Diameter Wells in Confined Aquifers: Verification, Identifiability, and Field Diagnostics abstract: Slug test interpretation can fail when measured recovery follows a time scale that differs from the classical Cooper–Bredehoeft–Papadopulos (CBP) finite-diameter well solution. This study derives a conformable slug test formulation by showing that a local weighted derivative converts the governing problem into the classical solution evaluated in transformed time. The formulation therefore does not introduce a nonlocal memory kernel; instead, it provides a reproducible diagnostic with one fitted exponent for testing power law time scaling while retaining the finite-diameter wellbore storage boundary condition. The solution is evaluated using double-precision Stehfest numerical inversion with 12 terms and is verified by the exact classical limit and by sensitivity tests on the number of inversion terms. Type curves, Morris sensitivity indices, objective function slices, synthetic benchmarks, and measured slug test data from the Minnelusa and Madison aquifer system near Spearfish, South Dakota, are used to evaluate the added exponent. A benchmark with an exponent above one recovered fitted exponents of 1.397 without noise and 1.417 under Gaussian noise with a standard deviation of 0.01. Field fitting over exponents from 0.5 to 2.0 reduces root mean square error and information criteria relative to the classical model for the analyzed datasets, especially the LA-88B pressure tests. However, exponents above one are interpreted only as accelerated transformed time behavior, not as conventional fractional orders or unique physical mechanisms. Comparison with a published semi-analytical slug test model that represents near-well formation damage and non-Darcy flow for the same field dataset supports using the conformable exponent as a diagnostic indicator of time-scale mismatch alongside mechanistic slug test models.

Chloride-assisted electro-oxidation for phosphorus recovery from acidic wastewater via ferric phosphate precipitation

title: Chloride-assisted electro-oxidation for phosphorus recovery from acidic wastewater via ferric phosphate precipitation abstract: Recovering phosphorus from acidic wastewater remains challenging because the highly soluble phosphate is complex to precipitate. This study presents an electro-oxidation precipitation route that converts ferrous (Fe(II)) to ferric (Fe(III)) using in-situ generated reactive chlorine species (RCS), enabling efficient ferric phosphate formation at low pH. The roles of Fe(II) sources, pH, current density, and Fe(II):P ratios were systematically evaluated to clarify the governing mechanism and optimize process performance. In chloride-containing systems, RCS accelerated Fe(II) conversion and enhanced phosphorus removal, achieving up to 98% recovery with a clear correlation between oxidation-reduction potential (ORP) and Fe(II) conversion. pH control (1.7–1.9) improved process stability, minimized competing reactions, and significantly enhanced sludge settleability. Higher current densities shortened the reaction time for complete Fe(II) oxidation, while increased Fe(II):P ratios compensated for Fe loss at the cathode, maintaining the stoichiometric 1:1 Fe:P precipitation behavior. The process costs more than electrochemical crystallization process that produces vivianite (E-Vivianite) due to high energy and iron expenses, but optimization and ferric phosphate's higher value yield economic benefits for acidic wastewater and batteries. Characterization of the recovered solids confirmed the transformation of amorphous FePO4 into a highly crystalline, thermally stable form of FePO4 after calcination, making it suitable for energy-storing applications. Overall, this work demonstrates a robust strategy for phosphorus removal from highly acidic wastewater while producing value-added ferric phosphate materials.

Chloride-assisted electro-oxidation for phosphorus recovery from acidic wastewater via ferric phosphate precipitation

Quantifying situation-dependent uncertainty in tropical cyclone track forecasts with a recurrent neural network approach

title: Quantifying situation-dependent uncertainty in tropical cyclone track forecasts with a recurrent neural network approach abstract: Reliable forecasts of tropical cyclone tracks are essential for anticipating the environmental and societal impacts of these extreme weather events. In this study, we apply the long short-term memory (LSTM) model to better represent the spatiotemporal correlations of typhoon track forecast errors and to provide situation-dependent Cone of Uncertainty (CoU). The datasets used include the Central Weather Administration’s (CWA) official typhoon track forecasts, as well as deterministic and ensemble forecasts from the European Centre for Medium-Range Weather Forecasts and the National Centers for Environmental Prediction models. In most situations, the LSTM-calibrated track forecasts generally outperform the CWA official forecasts. More importantly, the estimated CoU can reasonably cover the observed tracks. Relationships between CoUs and factors such as typhoon translation speed and direction are also examined. Incorporating global numerical model information further reduces the radius of forecast uncertainty while maintaining reliable coverage. Overall, this study demonstrates that the LSTM-based approach offers a reliable representation of typhoon track forecast uncertainty, which provides valuable insights into situation-dependent uncertainty quantification for extreme weather prediction.

Effects of Microplastics on Nitrogen Removal Performance of Enriched Anammox Cultures

title: Effects of Microplastics on Nitrogen Removal Performance of Enriched Anammox Cultures abstract: Microplastics (MPs) and their chemical leachates are increasingly detected in landfill leachate, raising concerns about impacts on biological nitrogen removal. This study examined the effects of low-density polyethylene (LDPE) and polypropylene (PP) MPs on anaerobic ammonium oxidation (anammox) performance using suspended, attached, and granular biomass. The results showed that exposure to LDPE and PP MPs did not significantly inhibit specific anammox activity (SAA) across all anammox biomass types. However, the leachates of LDPE and PP MPs under relevant EU migration testing guidelines could cause transient inhibition. Non-targeted GC-MS analysis identified 31 and 37 leachable compounds from LDPE and PP, including the toxic plasticizer dibutyl phthalate (DBP). DBP caused concentration-dependent but transient inhibition of nitrogen removal in granular biomass, peaking at 29.4% after 5 h at 100 mg/L, with full recovery within 24 h. Higher DBP retention was observed in granular and attached growth biomass compared to suspended growth biomass. Crucially, complex biomass structures buffer these effects, emphasizing the need to assess both physical and chemical MP aspects in wastewater systems. Consequently, attached growth and granular systems are recommended over suspended growth configurations for leachate treatment, owing to their superior resilience to toxic shock and enhanced retention capabilities.

Monitoring of algal species growth in drinking water reservoirs using on-site fluorescent probe: Impact of suspended solids composition on cell counting

title: Monitoring of algal species growth in drinking water reservoirs using on-site fluorescent probe: Impact of suspended solids composition on cell counting abstract: Evaluation of algal growth potential (AGP) is critical to prevent reservoir eutrophication. However, accurately and promptly monitoring algal species and counts via the microscopic method is challenging due to interference from suspended solids (SS). The study aimed to determine the composition and the impact of SS in six major drinking water reservoirs in Taiwan over a 6-month period (November to April). A fluorescent probe was used to quantify algal cells and to determine species diversity. Pearson’s correlation was employed to assess the relationship among various indicators, including chlorophyll-a, total phosphate (TP), and SS. The results indicated that TP significantly enhances AGP, showing a moderate correlation (γ ¼ 0.54) with algal suspended solid (ASS). The ASS can serve as an alternative and more robust indicator for assessing AGP in reservoirs. However, algal cell counting may be hindered by inorganic particles, resulting in lower accuracy compared to microscopic enumeration. Consequently, the ‘relative algae count’ emerges as a practical indicator to reach cost-effective species-specific monitoring for reservoir management. Furthermore, the fluorescence probe proved effective in distinguishing algal species fractions (e.g., diatoms, green algae, cyanobacteria, and cryptophyta), even under the impact of SS. It was concluded that fluorescent probing is a rapid-response method for AGP monitoring across diversified drinking reservoirs.

New Challenges for Tropical Cyclone Track and Intensity Forecasting in an Unfavorable External Environment in the Western North Pacific—Part II: Intensifications near and North of 20° N

title: New Challenges for Tropical Cyclone Track and Intensity Forecasting in an Unfavorable External Environment in the Western North Pacific—Part II: Intensifications near and North of 20° N

New Challenges for Tropical Cyclone Track and Intensity Forecasting in Unfavorable External Environment in Western North Pacific. Part I. Formations South of 20° N

title: New Challenges for Tropical Cyclone Track and Intensity Forecasting in Unfavorable External Environment in Western North Pacific. Part I. Formations South of 20° N abstract: A pre-operational test started in mid-July 2024 to demonstrate the capability of the ECMWF’s ensemble (ECEPS) to predict western North Pacific Tropical Cyclones (TCs) lifecycle tracks and intensities revealed new forecasting challenges for four typhoons that started well south of 20° N. As Typhoon Gaemi (05 W) was moving poleward into an unfavorable environment north of 20° N, a sharp westward turn to cross Taiwan was a challenge to forecast. The pre-Yagi (12 W) westward turn across Luzon Island, re-formation, and then extremely rapid intensification prior to striking Hainan Island were challenges to forecast. The slow intensification of Bebinca (14 W) after moving poleward across 20° N into an unfavorable environment was better forecast by the ECEPS than by the Joint Typhoon Warning Center (JTWC), which consistently over-predicted the intensification. An early westward turn south of 20° N by Kong-Rey (23 W) leading to a long westward path along 17° N and then a poleward turn to strike Taiwan were all track forecasting challenges. Four-dimensional COAMPS-TC Dynamic Initialization analyses utilizing high-density Himawari-9 atmospheric motion vectors are proposed to better define the TC intensities, vortex structure, and unfavorable environment for diagnostic studies and as initial conditions for regional model predictions. In Part 2 study of selected 2024 season TCs that started north of 20° N, more challenging track forecasts and slow intensification rates over an unfavorable TC environment will be documented.

Analysis of Green Product Selection Factors by Sellers: A Case Study of Biodiversity-friendly Agricultural Products,

title: Analysis of Green Product Selection Factors by Sellers: A Case Study of Biodiversity-friendly Agricultural Products, abstract: With the growing emphasis on environmental conservation and sustainable agriculture, eco-friendly farming has emerged as a key strategy in promoting environmental protection. However, how such green products can successfully enter the market, attract consumers, and gain the support of distribution channels remains to be fully understood. This study employs face-to-face questionnaire interviews and the Analytic Hierarchy Process (AHP) to analyze the factors influencing distribution channels' selection of green product content. The questionnaire is structured around four main dimensions—logistics, financial flow, information flow, and product marketing—encompassing nine evaluative indicators. Through direct interviews, the study captures the preferences and decision-making intentions of key stakeholders regarding the production and consumption of eco-friendly agricultural products. The findings reveal that respondents prioritized "product marketing" most highly, with a weight of 0.372, followed by "information flow" at 0.245, "logistics" at 0.216, and lastly "financial flow" at 0.168. The study underscores that the foremost consideration for distributors when selecting green products lies in product marketing. Most distribution stakeholders believe that, in promoting biodiversity-friendly or organic agricultural products, distinguishing them from conventional products is crucial. Thus, the image conveyed by the product and the transparency of its production-related information are deemed critical factors in the successful marketing and promotion of such green products.

Innovative hyper-thermophilic aerobic submerged membrane distillation bioreactor for wastewater reclamation

title: Innovative hyper-thermophilic aerobic submerged membrane distillation bioreactor for wastewater reclamation abstract: For the first time, a hyper-thermophilic aerobic (>60 °C) bioreactor has been integrated with direct submerged membrane distillation (MD), highlighting its potential as an advanced wastewater treatment solution. The hyper-thermophilic aerobic bioreactor, operating up to 65 °C, is tailored for high organic removal, while MD efficiently produces clean water. Throughout the study, high removal rates of 99.5% for organic matter, 96.4% for ammonia, and 100% for phosphorus underscored the impressive adaptability of microorganisms to challenging hyper-thermophilic conditions and a successful combination with the MD process. Despite the extreme temperatures and substantial salinity accumulation reaching up to 12,532 μS/cm, the biomass of microorganisms increased by 1.6 times over a 92-day period, representing their remarkable resilience. The distillation flux ranged from 6.15 LMH to 8.25 LMH, benefiting from the temperature gradient in the hyper-thermophilic setting and the design of the tubular submerged MD membrane module. The system also excels in pH control, utilizing fewer alkali and nutritional resources than conventional systems. Meiothermus, Firmicutes, and Bacteroidetes, the three dominant species, played a crucial role, showcasing their significance in adapting to high salinity and decomposing organic matter.

Hybrid Genetic Algorithm to Parameter Identification of Structural Systems with Added-Damping-and-Stiffness Device

title: Hybrid Genetic Algorithm to Parameter Identification of Structural Systems with Added-Damping-and-Stiffness Device abstract: The structural parameters may be deviated from the design values due to the yielding or the fatigue of the material strength. In this regard, the dynamic characteristics may also be changed due to the damage of the structure. In order to realize the dynamic behavior of structural systems, we can determine the dynamic models and parameters by system identification techniques. The method proposed for the parameter identification of nonlinear systems in this paper is the hybrid genetic algorithm combining Wen’s model as the restoring force model for each story shear. The process of exploring this algorithm is demonstrated by the simulated single-degree-of-freedom system. Finally, the method was applied to the three-story structural models with added-damping-and-stiffness devices mounted on the shaking table. The ground motion records used for these models are time histories of El Centro earthquake adjusted to different intensities. The results showed that the D20H100 model of added-damping-and-stiffness devices experienced slight damage when subjected to the excitation of the El Centro earthquake with PGA values equal to 500 gal and received more damage when the excitation increased to 600 gal.

The flow within the head of a gravity current

title: The flow within the head of a gravity current abstract: High-resolution simulations of gravity currents in the lock-exchange configuration are conducted to study the flow within the head. The simulations exhibit the geometric features of the head as reported in the laboratory experiments and numerical simulations, and provide more detailed information on the flow within the head of a gravity current. The flow in the lower part of the head, where the lobes and clefts are forming at the leading edge, is qualitatively different from but interconnected to the flow in the upper part of the head, where steepening bulges are protruding from the upright surface above the clefts. Interestingly, regions of positive and negative streamwise vorticity are observed not only in the lower part of the head but also in the upper part of the head at staggered spanwise locations. We have shown that both the streamwise vorticity at the leading edge of the lobes in the lower part of the head and the streamwise vorticity at the steepening bulges in the upper part of the head are contributed from the twisting of spanwise vorticity into the streamwise direction, due to the geometric features of the lobes and the steepening bulges, and contributed from the baroclinic production of vorticity. Our results from visualization using tracers indicate that the ambient fluid ingested in and rising from the clefts is being swept towards the leading edge of a gravity current before being carried upwards from the leading edge to the upright surface above the left and right neighbouring lobes. Furthermore, the heavy fluid inside a lobe may descend towards the bottom boundary, move forward towards the leading edge and outwards towards the neighbouring clefts, and ultimately be carried upwards to the upright surface above the left and right neighbouring lobes. With the knowledge that the erosive power of a gravity current is concentrated in the head region, it is plausible that the bed material, once resuspended by a gravity current, may be lifted up away from the bottom boundary and be dispersed in both the streamwise and spanwise directions. The present study complements existing findings in the literature and provides new insights into the three-dimensional flow field within the head of a gravity current.

Use of packed scrap iron anodes for continuous electrochemical Cr ( VI ) reduction process in electroplating wastewater

title: Use of packed scrap iron anodes for continuous electrochemical Cr ( VI ) reduction process in electroplating wastewater

Complete Cu removal through Fe(II) mediated decoupling of CuEDTA complexes from simulated industrial wastewater with simultaneous precipitation

title: Complete Cu removal through Fe(II) mediated decoupling of CuEDTA complexes from simulated industrial wastewater with simultaneous precipitation abstract: A complete removal of Cu from CuEDTA complexes by replacement/precipitation reactions using ferrous ions was realized. The effects of pH, iron dosage and reactions time on Cu removal were evaluated. The results were explained with the aid of chemical equilibrium modeling. Fe(III) ions effectively liberate Cu(II) ions from CuEDTA complexes by the replacement reaction at an acidic pH region, but the precipitation of ferric hydroxides at elevated pH levels renders a negative effect on Cu removal. In contrast, Fe(II) ions replace Cu(II) effectively at an alkaline pH region, where both replacement and precipitation of Cu can take place simultaneously. Cu removal was enhanced and was independent of the precipitation time when Fe(II) was dosed instead of Fe(III), reaching 100% removal of Cu at Cu:EDTA:Fe molar ratio of 1:1:5. The treatment efficacy of the replacement/precipitation processes for Cu removal followed by Fenton process for COD removal was compared with that of Fenton process for COD removal followed by alkaline precipitation for Cu removal. A complete Cu removal was achieved by the former, whereas only 40%–66% of Cu was removed by the latter.

Efficient Cu removal from CuEDTA complex-containing wastewater using electrochemically controlled sacrificialiron anode

title: Efficient Cu removal from CuEDTA complex-containing wastewater using electrochemically controlled sacrificialiron anode

Electrochemical crystallization for phosphate recovery from an electronic industry wastewater effluent using sacrificial iron

title: Electrochemical crystallization for phosphate recovery from an electronic industry wastewater effluent using sacrificial iron

Cryolite (Na3AlF6) crystallization for fluoride recovery using an electrolytic process equipped with a sacrificial aluminum anode

title: Cryolite (Na3AlF6) crystallization for fluoride recovery using an electrolytic process equipped with a sacrificial aluminum anode abstract: An electro-crystallization process equipped with a sacrificial aluminum anode was operated under an optimum condition to promote the formation of crystalline cryolite for the recovery of fluoride from synthetic F-containing wastewater. The effects of pH, Al/F molar ratio, initial F concentration, and electrolytes were investigated experimentally, and the results were compared with data obtained from chemical equilibrium modeling. Cryolite was successfully produced under optimum pH values of 5 to 6 and Al/F molar ratios of less than 1/6. The F removal increased with increasing Al/F molar ratio until reaching the molar ratio of 1/6 and decreased thereafter due to the formation of AlFn3−n species. The adsorption of AlFn3−n by Al(OH)3 precipitates contributed part of F removal. The removal efficiency reached 100% when the initial fluoride concentration was high while it was around 90% with the low initial fluoride concentration. XRD and SEM/EDX analysis showed that the obtained solids matched well to the commercial cryolite. Finally, the operating costs of chemical-crystallization (the process with Al ions added chemically) and electro-crystallization were compared, and the cost of the former was less than the latter. Energy consumption was the main contributor to the operating cost of the electro-crystallization process.

High-pressure electrocoagulation system with periodic air replenishment for efficient dye wastewater treatment: Reaction dynamics and cost evaluation

title: High-pressure electrocoagulation system with periodic air replenishment for efficient dye wastewater treatment: Reaction dynamics and cost evaluation abstract: Ferrous ions are the major Fe species generated from sacrificial iron anodes, but ferric ions are the more active ingredients for the removal of organic matters in the acidic pH region. Therefore, a novel high-pressure electrocoagulation (HPEC) system was devised to facilitate the Fe(II)-to-Fe(III) conversion under acidic pH conditions. The effects of operation pressure (0–3 bar) and initial pH value (3–10) on the removal of color and organics from synthetic dye wastewater containing Eriochrome Black T (EBT) were investigated. The operation costs of the HPEC were compared with that of the conventional electrocoagulation (CEC) processes. The HPEC outperformed the CEC, achieving complete color removal after a short reaction time. In the initial pH range of <8, the HPEC achieved substantial color (∼100%) and organic carbon (∼78%) removals. However, a sharp drop in the removal efficiency occurred at the pH of >8 owing to the formation of Fe(III)-EBT complexes and the ineffective removal of these complexes by coagulation or adsorption. The high removal efficiencies attained under acidic and neutral pH conditions were attributed to the effective Fe(II)-to-Fe(III) conversion by dissolved oxygen under pressure followed by the formation of Fe(OH)

Electrochemical Cr(VI) reduction using a sacrificial Fe anode: Impacts of solution chemistry and stoichiometry

title: Electrochemical Cr(VI) reduction using a sacrificial Fe anode: Impacts of solution chemistry and stoichiometry

Electrochemical treatment for simultaneous removal of heavy metals and organics from surface finishing wastewater using sacrificial iron anode

title: Electrochemical treatment for simultaneous removal of heavy metals and organics from surface finishing wastewater using sacrificial iron anode abstract: Surface finishing wastewater having low pH (∼2) and high conductivity (>11 mS/cm) was treated by electrocoagulation (EC) or electrochemical Fenton (ECF) processes using sacrificial iron anodes. Under the same theoretical Fe dosage, the effects of electrolytic time, initial pH, and current density on the simultaneous removal of organic and heavy metal were investigated. A complete metal removal was achieved even at the low current density of 24.2 mA/cm2 and short electrolytic time of 4 min, whereas approximately 40% of chemical oxygen demand was removed. Increasing the electric current density did not improve removal efficiencies, but consumed more electric energy. Low current conditions produced a brown color sludge associated with ferric hydroxide. On the contrary, a greenish color sludge was created at a high current due to the formation of ferrous hydroxide. The formation of ferrous hydroxide impacted the treated water quality. The ECF was employed to overcome the low COD removal by the EC, achieving >67% of COD removal. The costs of ECF processes were slightly greater than that of chemical coagulation, but achieving a lot greater heavy metal removals. ECF process can be a promising method for simultaneous removal of heavy metal and organics from complex industrial wastewater.

Sustainable Fluoride Removal with Scrap Aluminum: Co-producing Cryolite and Hydrogen

title: Sustainable Fluoride Removal with Scrap Aluminum: Co-producing Cryolite and Hydrogen abstract: This study presents a novel continuous process for fluoride removal and re- source recovery as cryolite, using a scrap aluminum-packed column. Efficient aluminum dissolution in hydrofluoric acid (HF) generates hydrogen gas and provides cost-saving alkalinity. The process achieves high efficiency (Al/F molar ratio of 2/6) within short Empty Bed Contact Times (15 min) and at low HF concentrations (500 mg/L). Solution pH plays a crucial role, with Al/F ratios above 1 achievable at pH below 4. The exothermic reaction requires temperature control, with a strong correlation (R²=0.99) between HF concentration and heat generation. Hydrogen production matches theoretical predictions. Cryolite synthesis was confirmed at optimized pH (5–5.5) with a 1:1 bypass ratio, achieving 98 % fluoride removal. XRD and SEM- EDS analyses verified cryolite formation. This approach offers a promising solution for industrial fluoride management, resource recovery, and clean hydrogen production.

Dissolution of aluminum hydroxide to provide Al and to neutralize acidity for the removal and recovery of fluoride through cryolite crystallization

title: Dissolution of aluminum hydroxide to provide Al and to neutralize acidity for the removal and recovery of fluoride through cryolite crystallization abstract: Dissolution of aluminum hydroxide (Al(OH)3(s)) was investigated for providing Al and at the same time neutralizing the acidity generated in the recovery of fluoride through the crystallization of cryolite. The alkalinity provided by the dissolution of Al(OH)3(s) combined with Na2CO3 reduces the total treatment cost for fluoride recovery by 45%, compared to when other aluminum salts were used. In this study, two types of aluminum hydroxide having different degrees of crystallinity of 61.53% and 25.57%, denoted as crystalline Al(OH)3(s) (CAH) and amorphous Al(OH)3(s) (AAH), respectively, were investigated. The results showed that the dissolution of AAH was very efficient but an excess amount of AAH adsorbed the freshly formed complexes, impairing the purity of cryolite. On the other hand, the dissolution of the CAH was mostly dependent on the time, the Al dosage, and the initial pH of the solution. Upon reaching equilibrium, the dissolved Al to the initial F molar ratio reached 2/6. With the mixed volume ratio of 1:1 between the raw HF solution and the HF solution being equilibrated with CAH initially, the removal of F reached 96% and the cryolite formation was positively confirmed based on the XRD analysis of the resulting solid.

Cyanide Removal and Recovery by Electrochemical Crystallization Process

title: Cyanide Removal and Recovery by Electrochemical Crystallization Process abstract: Alkaline chlorination, an efficient but high chemical cost process, is commonly employed for cyanide (CN−) removal from CN-rich wastewater streams. CN− removal and recovery through the precipitation of Prussian Blue (Fe4III[FeII(CN)6]3, PB) or Turnbull’s Blue (Fe3II[FeIII(CN)6]2, TB) were realized using iron salts, leading to a cost-effective and sustainable process producing a valuable recovery product. However, the precipitation of PB and TB is highly affected by pH and dissolved oxygen (DO). CN− removal and recovery from CN-containing water by crystallization of PB and/or TB were investigated using dissolved iron that was electrochemically generated from a sacrificial iron anode under various pH values, initial CN− levels (10 to100 mg/L) and DO levels (aeration, mechanical mixing, and N2 purging). It was shown that the complexation of CN− with Fe ions prevented the vaporization of HCN under acidic pH. At pH of 7 and initial CN− concentration of 10 mg/L, CN− removal efficiency increases linearly with increasing Fe:CN− molar ratios, reaching 80% at the Fe:CN− molar ratio of 5. A clear blue precipitate was observed between the pH range of 5–7. CN− removal increases with increasing initial CN− concentration, resulting in residual CN− concentrations of 8, 7.5 and 12 mg/L in the effluent with the Fe:CN− molar ratio of 0.8 for initial concentrations of 10, 50 and 100 mg CN−/L, respectively. A polishing treatment with H2O2 oxidation was employed to lower the residual CN− concentration to meet the discharge limit of <1 mg CN−/L.

Scrap iron packed in a Ti mesh cage as a sacrificial anode for electrochemical Cr(VI) reduction to treat electroplating wastewater

title: Scrap iron packed in a Ti mesh cage as a sacrificial anode for electrochemical Cr(VI) reduction to treat electroplating wastewater abstract: A novel sacrificial anode comprised of scrap iron packed inside a cage made of titanium mesh was developed for Cr(VI) reduction. With electric currents applied, the surface passivation of scrap iron electrode could be avoided. Due to the large surface area with open structures provided, the applied current densities (1.18–3.54 mA/cm

Analytical Framework for Fast Identification of Hydrogeological Boundaries and Aquifer Parameters in Confined Aquifers

title: Analytical Framework for Fast Identification of Hydrogeological Boundaries and Aquifer Parameters in Confined Aquifers abstract: Hydrogeological boundaries, such as recharge boundaries (e.g., rivers) and impervious boundaries (e.g., faults), significantly influence groundwater flow and resource management. Previous methods have improved the estimation of aquifer parameters and the distance from the observation well to the image well; however, they do not address boundary type identification within a unified framework and require graphical steps to determine the locations of the image well and the boundary. Hence, this study develops an analytical approach for confined aquifers by using piecewise linear regression combined with a Bayesian classification to determine the boundary type. It then integrates the Theis method, image well theory, and simulated annealing to simultaneously identify the image well location and aquifer parameters, including transmissivity and storage coefficient. Finally, the boundary location and orientation are separately delineated by equations developed based on known locations of the pumping well and the image well. The proposed framework is applied to pumping test data from two field sites — near the Tongue River in Montana and Dry Lake in Nevada (U.S. Bureau of Reclamation) — demonstrating its accuracy and practical applicability. By unifying boundary type classification, boundary location determination, and parameter estimation within a single analytical framework, this method provides a more comprehensive and time-efficient solution than existing approaches. Its implementation can improve groundwater resource management and support infrastructure development in settings where hydrogeological boundaries play a crucial role.

Assessment of temperature dynamics and microbial community responses in aerobic membrane bioreactors from mesophilic to hyper-thermophilic conditions

title: Assessment of temperature dynamics and microbial community responses in aerobic membrane bioreactors from mesophilic to hyper-thermophilic conditions

Life-Cycle Assessment of Municipal Solid Waste Incineration Fly Ash Recycling as a Feedstock for Brick Manufacturing

title: Life-Cycle Assessment of Municipal Solid Waste Incineration Fly Ash Recycling as a Feedstock for Brick Manufacturing abstract: The recovery of municipal solid waste incineration (MSWI) fly ash is currently considered to be the most viable solution for its management. However, in developing resource recovery technologies, it is crucial to consider the overall environmental impact. This study employed a life-cycle assessment (LCA) to compare environmentally friendly red bricks partially utilizing MSWI fly ash as a raw material with conventional red bricks. The results demonstrate that the use of phosphoric acid during the resource recovery process imposes the most significant environmental burden, followed by electricity consumption. To address this issue, in this study, we simulated the replacement of phosphoric acid with phosphoric acid monohydrate recovered from discarded fire extinguishers, resulting in the production of second-generation environmentally friendly red bricks. The analysis revealed that the environmentally friendly red bricks exhibited a mere 5.52% increase in total environmental impact compared with traditional red bricks. Moreover, by stabilizing heavy metals using recovered phosphoric acid monohydrate, the second-generation environmentally friendly red bricks achieved an 8.75% reduction in total environmental impact relative to traditional red bricks. These findings highlight the environmental benefits of fly ash reuse in red brick production, and the incorporation of other industrial waste or byproducts could further enhance its efficacy. The application of the LCA facilitated the identification of key areas for improvement and enabled precise evaluation of the environmental benefits associated with waste reuse.

Enhancing photocatalytic performance of regular porous silver bromide structures through 3D printing

title: Enhancing photocatalytic performance of regular porous silver bromide structures through 3D printing abstract: This study introduces the innovative method of in-situ precipitation (ISP) 3D printing technology for fabricating photocatalyst structures capable of efficiently degrading water pollutants. The technology involves using silver nitrate aqueous solution to print directly on the surface of solidified NaBr aqueous solution, resulting in the formation of regular porous silver bromide structures. The structures are then densified through drying and sintering, followed by photoreduction using ultraviolet radiation to create Ag@(silver atom cluster)AgBr photocatalyst structures. Experimental results demonstrate the effectiveness of this photocatalyst structure in degrading azo dyes (Orange II) and eliminating Escherichia coli (E. coli) under visible light and ultraviolet light irradiation. The degradation of azo dyes and the sterilization of E. coli follow first-order kinetic reactions, with the photocatalyst module maintaining an 84.8% degradation rate after five recycling cycles. Complete elimination E. coli of the photocatalytic module is achieved within 120 min, and its sterilization effect follows a hyperbolic reaction. The study further confirms the durability and reusability of the photocatalyst structure, highlighting ISP 3D printing technology as a promising approach for fabricating efficient photocatalyst structures to address water pollution challenges in water treatment and environmental protection.

Tidal Signal Propagation in Coastal Aquifers Considering Semi-Permeable Boundaries and Partial Penetration Effects

title: Tidal Signal Propagation in Coastal Aquifers Considering Semi-Permeable Boundaries and Partial Penetration Effects abstract: Tidal fluctuations in coastal aquifers offer critical insights into the controls and dynamics of groundwater flow systems. This study presents a new analytical model designed to examine tide-driven variations in groundwater levels, particularly in systems with complex boundary conditions. Unlike previous models, the proposed model incorporates the effects of semi-permeable zones at interfaces and partial boundary penetration near estuaries. Sensitivity analyses were used to evaluate how intricate boundary configurations and specific aquifer characteristics influence the amplitude and phase shift of tidal signals in aquifers. The new analytical approach was also applied to data from a coastal aquifer in Hong Kong, and the results emphasized the importance of accounting for partial estuary penetration when evaluating tidal signal propagation. This approach significantly advances understanding of tidal signal propagation in coastal aquifers, offering a more comprehensive assessment of aquifer behavior that extends beyond hydraulic diffusivity.

A Method for Developing Seismic Hazard-Consistent Fragility Curves for Soil Liquefaction Using Monte Carlo Simulation

title: A Method for Developing Seismic Hazard-Consistent Fragility Curves for Soil Liquefaction Using Monte Carlo Simulation abstract: The objective of this study is to present a method for developing fragility curves for soil liquefac-tion that align with seismic hazards using Monte Carlo simulation. This approach can incorporate all uncertainties and variabilities in the input parameters. The seismic parameters, including earthquake magnitude (M) and associated peak ground acceleration (PGA), are jointly considered for the liquefaction assessment. The liquefaction potential and the resulting damages obtained by this method are more realistic. A case study is conducted using data from a sand-boil site in Yu-anlin, Changhua County, where liquefaction occurred during the 1999 Chi-Chi earthquake in Taiwan. The findings indicate that the liquefaction potential index, IL, the post-liquefaction settle-ment, St, and the liquefaction probability index, PW, are all appropriate parameters for assessing liquefaction damages. The fragility curves for soil liquefaction developed through this method can support the performance-based earthquake engineering (PBEE) approach, provide guidance for liquefaction evaluation to the ‘Taiwan Earthquake Loss Estimation System’-TELES, and serve as a foundation for scenario simulation and an earthquake early warning system for liquefaction damages.

Modified Fine Polyurethane Sponges with Polyvinyl Alcohol–Sodium Alginate Gel Coating as Bio-Carriers for Anammox Process

title: Modified Fine Polyurethane Sponges with Polyvinyl Alcohol–Sodium Alginate Gel Coating as Bio-Carriers for Anammox Process abstract: This research investigates suitable bio-carriers for the anaerobic ammonium oxidation (anammox) process. This study evaluates the efficiency of the anammox process by assessing nitrogen removal efficiency using five different bio-carriers: fine and coarse polyurethane (PU) sponges, a melamine sponge, Scotch Brite, and a loofah. Among the tested carriers, the reactor of the fine PU sponge media exhibited the highest nitrogen removal efficiency, achieving an 87% removal rate. This high efficiency was attributed to the substantial biomass containment, evidenced by a measured mixed liquor volatile suspended solids (MLVSS) amount of 1414 mg/L. Subsequently, the fine PU sponge, exhibiting the highest efficiency, was selected for further modification with a polyvinyl alcohol–sodium alginate (PVA-SA) gel coating to study the impact of methanol inhibition on nitrogen removal efficiency. An optimal modification condition was determined, utilizing concentrations of 8% PVA and 1.8% SA for the fine PU sponge media. The modified PU reactor exhibited the highest resistance to methanol inhibition, followed by the attached growth fine PU sponge reactor and suspended growth reactor. These findings suggest that there are benefits to using modified PU media for the anammox process in the field.

Revolutionizing Microalgae Harvesting and Cultivation with Living Membranes: A Leap Forward in Optimized Biomass Recovery and Lipid Production

title: Revolutionizing Microalgae Harvesting and Cultivation with Living Membranes: A Leap Forward in Optimized Biomass Recovery and Lipid Production

Innovative hyper-thermophilic aerobic submerged membrane distillation bioreactor for wastewater reclamation

title: Innovative hyper-thermophilic aerobic submerged membrane distillation bioreactor for wastewater reclamation

過壓密效應對土壤液化潛能影響之探討～以臺北盆地為例

title: 過壓密效應對土壤液化潛能影響之探討～以臺北盆地為例 abstract: 臺北盆地曾在民國六十年代以前，超抽地下水而造成地盤下陷，後來實施禁抽/管制措施後，因地下水位回升而產生過壓密效應；而目前慣常使用之土壤液化評估方法中，並未考慮過壓密效應所產生土壤組構強化之影響，且國內過去也較少有對這個影響因素進行探討，所以本研究乃蒐集及篩選臺北盆地過往重要工程案例，共658個試驗孔位之832組壓密試驗資料進行分析，評估過壓密效應對液化潛能高低及液化潛勢分區的影響。分析結果顯示，不論在設計地震或最大考量地震作用下，考慮過壓密效應皆明顯提高了土壤之抗液化強度，降低了臺北盆地之土壤液化潛勢，較切合歷史震害經驗。

Sustainable fluoride removal with scrap aluminum: Co-producing cryolite and hydrogen

title: Sustainable fluoride removal with scrap aluminum: Co-producing cryolite and hydrogen abstract: This study presents a novel continuous process for fluoride removal and re- source recovery as cryolite, using a scrap aluminum-packed column. Efficient aluminum dissolution in hydrofluoric acid (HF) generates hydrogen gas and provides cost-saving alkalinity. The process achieves high efficiency (Al/F molar ratio of 2/6) within short Empty Bed Contact Times (15 min) and at low HF concentrations (500 mg/L). Solution pH plays a crucial role, with Al/F ratios above 1 achievable at pH below 4. The exothermic reaction requires temperature control, with a strong correlation (R²=0.99) between HF concentration and heat generation. Hydrogen production matches theoretical predictions. Cryolite synthesis was confirmed at optimized pH (5–5.5) with a 1:1 bypass ratio, achieving 98 % fluoride removal. XRD and SEM- EDS analyses verified cryolite formation. This approach offers a promising solution for industrial fluoride management, resource recovery, and clean hydrogen production.

Enhancing membrane fouling control in wastewater treatment processes through artificial intelligence modeling: research progress and future perspectives

title: Enhancing membrane fouling control in wastewater treatment processes through artificial intelligence modeling: research progress and future perspectives abstract: Membrane filtration processes have demonstrated remarkable effectiveness in wastewater treatment, achieving high contaminant removal and producing high-quality effluent suitable for safe reuse. Membrane technologies play a primary role in combating water scarcity and pollution challenges. However, the need for more effective strategies to mitigate membrane fouling remains a critical concern. Artificial intelligence (AI) modeling offers a promising solution by enabling accurate predictions of membrane fouling, thus supporting advanced fouling mitigation strategies. This review examines recent progress in the application of AI models, with a particular focus on artificial neural networks (ANNs), for simulating membrane fouling in wastewater treatment processes. It highlights the substantial potential of ANNs, particularly the widely studied multi-layer perceptron (MLP) and other emerging configurations, to accurately predict membrane fouling, thereby enhancing process optimization and fouling mitigation efforts. The review discusses both the potential benefits and current limitations of AI-based strategies, analyzing recent studies to offer valuable insights for designing ANNs capable of providing accurate fouling predictions. Specifically, it provides guidance on selecting appropriate model architectures, input/output variables, activation functions, and training algorithms. Finally, this review highlights the critical need to connect research findings with practical applications in full-scale wastewater treatment plants. Key steps crucial to address this challenge have been identified, emphasizing the potential of AI modeling to revolutionize process control and drive a paradigm shift toward more efficient and sustainable membrane-based wastewater treatment.

Potential for spatial coexistence of a transboundary migratory species and wind energy development

title: Potential for spatial coexistence of a transboundary migratory species and wind energy development abstract: Global expansion in wind energy development is a notable achievement of the international community’s effort to reduce carbon emissions during energy production. However, the increasing number of wind turbines have unintended consequences for migratory birds and bats. Wind turbine curtailment and other mitigation strategies can reduce fatalities, but improved spatial and temporal data are needed to identify the most effective way for wind energy development and volant migratory species to coexist. Mexican free-tailed bats (Tadarida brasiliensis mexicana) account for a large proportion of known bat fatalities at wind facilities in the southwestern US. We examined the geographic concordance between existing wind energy generation facilities, areas of high wind potential amenable for future deployment of wind facilities, and seasonally suitable habitat for these bats. We used ecological niche modeling to determine species distribution during each of 4 seasons. We used a multi-criteria GIS-based approach to produce a wind turbine siting suitability map. We identified seasonal locations with highest and lowest potential for the species’ probability of occurrence, providing a potential explanation for the higher observed fatalities during fall migration. Thirty percent of 33,606 wind turbines within the southwestern US occurred in highly suitable areas for Mexican free-tailed bats, primarily in west Texas. There is also broad spatial overlap between areas of high wind potential and areas of suitable habitat for Mexican free-tailed bats. Because of this high degree of overlap, our results indicate that post-construction strategies, such as curtailing the timing of operations and deterrents, would be more effective for bat conservation than strategic siting of new wind energy installations.

ECMWF Ensemble Forecasts of Six Tropical Cyclones That Formed during a Long-Lasting Rossby Wave Breaking Event in the Western North Pacific

title: ECMWF Ensemble Forecasts of Six Tropical Cyclones That Formed during a Long-Lasting Rossby Wave Breaking Event in the Western North Pacific abstract: The ECMWF‘s ensemble (ECEPS) predictions are documented for the lifecycles of six tropical cyclones (TCs) that formed during a long-lasting Rossby wave breaking event in the western North Pacific. All six TC tracks started between 20° N and 25° N, and between 136° E and 160° E. All five typhoons recurved north of 30° N, and the three typhoons that did not make landfall had long tracks to 50° N and beyond. The ECEPS weighted mean vector motion track forecasts from pre-formation onward are quite accurate, with track forecast spreads that are primarily related to initial position uncertainties. The ECEPS intensity forecasts have been validated relative to the Joint Typhoon Warning Center (JTWC) Working Best Track (WBT) intensities (when available). The key results for Tokage (11 W) were the ECEPS forecasts of the intensification to a peak intensity of 100 kt, and then a rapid decay as a cold-core cyclone. For Hinnamnor (12 W), the key result was the ECEPS intensity forecasts during the post-extratropical transition period when Hinnamnor was rapidly translating poleward through the Japan Sea. For Muifa (14 W), the key advantage of the ECEPS was that intensity guidance was provided for longer periods than the JTWC 5-day forecast. The most intriguing aspect of the ECEPS forecasts for post-Merbok (15 W) was its prediction of a transition to an intense, warm-core vortex after Merbok had moved beyond 50° N and was headed toward the Aleutian Islands. The most disappointing result was that the ECEPS over-predicted the slow intensification rate of Nanmadol (16 W) until the time-to-typhoon (T2TY), but then failed to predict the large rapid intensification (RI) following the T2TY. The tentative conclusion is that the ECEPS model‘s physics are not capable of predicting the inner-core spin-up rates when a small inner-core vortex is undergoing large RI.