Water Purification System Research Articles

Identification of a defected fuel rod in the TRIGA R.C.-1 facility of the ENEA Casaccia Research Center: radiation protection aspects

The nuclear facility TRIGA RC-1 is located at the ENEA Casaccia Research Center in Rome. It is a thermal spectrum research reactor with a thermal power of 1 MW and a Mark III containment. The failure of the fuel cladding of the General Atomic TRIGA is a well-known phenomenon in the literature and is normally expected during its lifetime. Depending on the severity of the cracking, this results in the transfer of radioactivity from inside the fuel rods to the demineralized moderation and cooling water of the primary circuit. This occurs especially when the fuel is heated, as the temperature rise leads to an increase in the internal pressure inside the rods, causing fission products, especially gaseous ones, to be released through the cracks. The sustained release of these fission products over time causes impurities with longer half-lives (e.g., Cs-137) to accumulate in the primary water purification system and, in particular, in the ion exchange resin tank. Therefore, the detection of Cs-137 in the ion exchange resins of the primary water purification system of the reactor is a sufficiently clear indication of the occurrence of such disturbances. Indeed, Cs-137 is not only a direct fission product of U-235, but is also produced by the decay of Xe-137 (one of the major fission noble gasses), which, because of its physical nature, readily escapes through the rod cladding. To ensure worker protection from ionizing radiation during the identification and replacement of defective fuel rods, a special program of physical, environmental, and personal radiation protection monitoring was conducted. In addition to a brief description of the work performed, this report presents the results of radiometric measurements and associated individual dose assessment performed before, during, and after the identification and replacement of the defected fuel elements.

Hierarchical Cu dendrites@ CuO multifunctional nanowire mesh for solar-thermal clean water production

Solar-driven interfacial evaporation is recognized as an energy-efficient and sustainable approach to combat the global freshwater crisis, particularly in rural areas where continuous energy inputs are limited. Additionally, these regions often lack effective sterilization methods for their water sources. By incorporating photothermal materials with inherent antibacterial properties, water purification can be enhanced without relying on external sterilization steps. Herein, we designed a multi-functional photothermal (MFP) evaporator based on a Cu dendrite@ CuO with abundant nanowires via a template-free method for solar-thermal clean water production. Compared to flat-type structures, the MPF evaporator with its dendritic architecture not only exhibits efficient photon absorption but also expands the evaporation area by over sevenfold, facilitating enhanced water evaporation with an efficient pathway for water transfer. Under 1 kW m−2, the MFP evaporator achieves an impressive evaporation rate of 1.40 kg m−2 h−1 and an efficiency of 87.8 %. Furthermore, the MFP evaporator demonstrates remarkable antibacterial capabilities, effectively inhibiting bacterial growth in raw water by damaging bacterial cell walls. Hence, the as-prepared MFP evaporator exhibits tremendous potential as an innovative system for solar-driven interfacial water evaporation and purification.

Water and Sanitation Services at the Local Government Level in Bangladesh: An Analysis of SDG 6 Implementation Status and Way Forward

This study looks into the state of SDG 6 implementation at the local government level in Rajshahi City Corporation (RCC) with a focus on water and sanitation services. The research adopts a mixed-method approach and in-depth interviews to collect primary data. The study analyses the collected data using both quantitative and qualitative techniques. It has been found that large numbers of people do not always have access to enough water, demonstrating the problem of water scarcity in the region. According to the study, only a small percentage of participants tested their drinking water, which suggests that participants were not aware of the importance of water quality. Additionally, the lack of personal water purification and reuse systems is revealed by the research, indicating a gap in sustainable water management practices. Most of the city dwellers expressed dissatisfaction with the authority’s management of the water supply, indicating insufficient oversight and governance. The findings highlight the need for improved infrastructures, water treatment techniques, education campaigns, and governance mechanisms to effectively meet SDG 6 targets and guarantee residents of RCC access to clean water and sanitary facilities.

Оценка качества питьевой воды и разработка мер по улучшению: ООО «Водоканал» г. Льгов

During the study, samples were taken to assess the quality of drinking water in LLC Vodokanal, Lgov. Based on the results of the analyses, measures were developed, including the modernization of the water filtration and purification system, replacement of worn pipes, strengthening pollution control, improving technological processes and conducting educational campaigns for the population. Keywords: DRINKING WATER, DRINKING WATER QUALITY, DRINKING WATER QUALITY REQUIREMENTS, MEASURES TO IMPROVE THE QUALITY OF DRINKING WATER

Multifunctional Solar Evaporator with Adjustable Island Structure Improves Performance and Salt Discharge Capacity of Desalination.

Interfacial solar steam generation (ISSG) is the main method to get fresh water from seawater or wastewater. The balance between evaporation rate and salt resistance is still a major challenge for ISSG. Herein, a wood aerogel island solar evaporator (WAISE) with tunable surface structure and wettability by synthesizing poly(n-isopropylacrylamide)-modified multi-walled carbon nanotube photothermal layers. Compared to dense surface structure evaporators, interfacial moisture transport, thermal localization, and surface water vapor diffusion of WAISE are greatly promoted, and the evaporation rate of WAISE increased by 87.64%. WAISE allows for record performance of 200h continuous operation in 20% NaCl solution without salt accumulation. In addition, the photo-thermal-electric device is developed based on WAISE with continuous water purification, power generation, and irrigation functions. This work provides a new direction for the development of multifunctional water purification systems.

Photoelectrochemical advanced oxidation processes for simultaneous removal of antibiotics and heavy metal ions in wastewater using 2D-on-2D WS2@CoFe2O4 heteronanostructures

The presence of antibiotics in water poses significant threats to both human health and the environment. Addressing this issue requires the effective treatment of medical wastewater. Photoelectrochemical advanced oxidation processes (PEAOPs) are emerging as promising solutions for wastewater treatment. This process utilizes photocatalysts to convert charge carriers into reactive species such as hydroxyl radicals and superoxide ions, which are essential for degrading pollutants in wastewater. However, limitations in charge carrier separation and transport have hindered the efficiency of photoelectrochemical advanced oxidation processes. To overcome these limitations, we designed WS2@CoFe2O4 heterojunctions, optimizing their energy levels to enhance charge transport and separation. This improvement significantly increased the oxidation of antibiotics such as amoxicillin and azithromycin. Multiple reactions occurred at the WS2@CoFe2O4 heterojunctions during photoelectrochemical advanced oxidation processes, leading to the impressive degradation of up to 99% of antibiotics under visible light irradiation at 0.8 V. Urea and H2O2 acted as oxidation agents within photoelectrochemical advanced oxidation processes, amplifying the generation of hydroxyl radicals and superoxide ions, further enhancing antibiotic oxidation. Moreover, the WS2@CoFe2O4 photoanode efficiently oxidized toxic antibiotics while converting As(III) into the less harmful As(V). Crucially, recyclability tests confirmed the robustness of the WS2@CoFe2O4 photoanode, ensuring its suitability for prolonged use in photoelectrochemical advanced oxidation processes. Integrating WS2@CoFe2O4 photoanodes into water purification systems can enhance efficiency, reduce energy consumption, and improve economic viability. This technology's scalability and its ability to protect ecosystems while conserving water resources make it a promising solution for addressing the critical issue of antibiotic pollution in water environments.

Optimization of designing the systems for waste water purification from waterworks operating with low-turbidity waters

Optimization of designing the systems for waste water purification from waterworks operating with low-turbidity waters

Investigation of micro lattice spiral wound membrane structures availing DLP and FDM techniques for water treatment

This study addressed the challenge of reducing water contaminants using Spiral Wound Membrane (SWM) units in desalination and water treatment. Through additive manufacturing, we developed complex micro-lattice feed-spacer structures using FlexBLK 20, Pro-BLK10, ToughBLK 20, PLA, PETG, and ABS materials. The AHPTOPSIS statistical method indicated an ideal solution with Digital Light Processing (DLP) conditions showing a 20 μm layer thickness, FlexBLK-20 material, diamond structure, and for Fused Deposition Modeling (FDM) conditions, a 0.1 mm layer thickness, PLA material, and gyroid structure. Significant findings include a decrease in surface roughness by 79.67%–85.25% for DLP, an elongation increase of 50%–91.67%, and tensile strength improvement between 0.07%–40.83%. DLP printed feed spacers showcased better surface distributions than FDM, attributed to finer layers and higher density printing. Additionally, DLP printing resulted in a 32.02% increase in residual stress, suggesting superior compressive resistance. In thermal analyses, both DLP and FDM materials showed thermal stability up to 380 °C–450 °C. This research indicates that DLP printed feed spacers, with their enhanced properties, are potentially more efficient for water purification systems, providing smoother surface, better filtration, and increased durability.

Novel application of (NH4)2Mo3S13 for vanadium adsorption: Experiments, characterization, kinetic and equilibrium modeling

The adsorption of vanadium on (NH4)2Mo3S13 was analyzed via experimental and theoretical approaches. Kinetic and equilibrium adsorption data were quantified at 293–323 K and pH 3.2. Vanadium kinetics followed a pseudo-first order equation with adsorption rate constants ranging from 0.006 to 0.032 min−1, while the maximum experimental vanadium adsorption capacities ranged from 9.9 to 362 mg/g under tested operating conditions. Equilibrium data were fitted by a monolayer model that considered that the vanadium ions were removed via two different active sites of (NH4)2Mo3S13 surface. These adsorption sites were related to the Mo moieties of this material. The calculated adsorption capacities of these active sites followed the next trend: Q1 (293 K) > Q2 (293 K), Q2 (303 K) > Q1 (303 K) and Q2 (313 K) > Q1 (313 K). In particular, the calculated saturation vanadium adsorption capacities were 124 – 376 mg/g. The impact of adsorption temperature on the calculated number of vanadium ions that were adsorbed by both active sites was also studied. It was concluded that the temperature facilitated the adsorption of vanadium ions via the first active site of (NH4)2Mo3S13 surface, while an opposite trend was identified regarding the second type of active site. The interaction energies involved in the adsorption of both active sites were also calculated. These results indicated that both sites contributed in different degree to reduce the vanadium concentrations in the aqueous solutions for depollution purposes. Overall, this study provides useful insights on the vanadium adsorption mechanism for an alternative and competitive adsorbent, which is promising to be implemented in large-scale water purification systems.

Effect Mass of Silica Sand on Reducing Fe Concentration in Water Purification Systems

This study aims to determine the effect of silica sand mass in the air purification system on the decrease in Fe concentration. The type of research used is experimental research. The water purification media used in the research were silica sand and gravel. The mass of gravel used in the water purification system is constant, namely 500 grams. The mass of silica sand used varies, namely 200 grams, 400 grams, 600 grams, 800 grams and 1000 grams. The research was carried out through three stages, namely the stages of preparation, implementation, and data collection. The effect of the mass of silica sand in the air purification system on decreasing the concentration of Fe showed positive results. The results of research with a fixed mass of gravel and varying masses of silica sand showed a decrease in Fe concentration after water purification with a value that met environmental health quality standards and water health requirements Fe (iron) content below 1 mg/L or ppm so that the water worth using.

Study of bismuth metal organic skeleton composites with photocatalytic antibacterial activity

A composite based on Ag and carbon quantum dot (CQDs) doped bismuth metal organic framework (CAU-17) was synthesized by a one-step thermal solvent in situ growth. The microstructure, chemical composition, morphology, photogenerated electron-hole pairs, and photocatalytic activity of the composite were characterized. The produced composite with its unique energy band structure, enhances the visible light absorption and effectively delays the recombination of the photogenerated carriers. On the other hand, the modification with CQDs increases the concentration and transport rate of photogenerated carriers mainly attributed to their superior electron transport capacity and light trapping ability. The photocatalytic antibacterial effect of CAU-17/Ag/CQDs against common Gram-positive, Gram-negative bacteria (Staphylococcus aureus, Escherichia coli) and drug-resistant bacteria (methicillin-resistant Staphylococcus aureus), as well as its inhibition against HepG2 tumor cell were investigated. The results showed that CAU-17/Ag/CQDs exhibited a photocatalytic antibacterial effect with an inactivation rate as high as 99.9 %. At the low dose (0.2 mg/mL), CAU-17/Ag/CQDs indicated a significant inhibition against bacterial growth 20 min after visible light exposure, whereas at the concentration of 0.5 mg/mL, CAU-17/Ag/CQDs completely killed all the tested bacteria. At the concentration of 0.8 mg/mL, the inhibition rate against HepG2 tumor cells reached 75 %. The excellent photocatalytic property of the as prepared composite contributed to the doping of Ag and CQDs, which fundamentally altered the morphology and energy band distribution. Such a composite can be developed into an effective photocatalytic disinfection system and applied to water purification systems, biofilm rejection, combating different antibiotic resistances, and tumor therapy.

Silver substituted cobalt zinc ferrites as magnetic antimicrobials

Silver-substituted cobalt zinc ferrite series, CoxAg0.5-xZn0.5Fe2O4 (x = 0.4, 0.3, 0.2, 0.1), is synthesized using the citrate gel method, wherein ferrite formation is achieved at 600 °C. The low-temperature crystallization results in agglomerated and porous ferrites. In this sample preparation methodology, as the silver content in the series increases, metallic silver deposits at the grain boundaries, and vacancies are created at the octahedral sites. With a further increase in silver content, the magnitude of magnetic properties decreases. Antimicrobial activity increases and further decreases with an increase in silver content. The composition Co0.4Ag0.1Zn0.5Fe2O4 exhibits both magnetic and antimicrobial behaviour. These materials can potentially be beneficial in the manufacture of removable antimicrobial agents for water purification and drug delivery systems.

Lignocellulosic magnetic biochar with multiple functionality; A green chelating system for water purification

For the bioremoval of Fe(III) ions, an active magnetic filter media is synthesized by ultrasound centrifugation. By coprecipitation a magnetic nanoparticles was synthesized, it is then multi-functionalised with a chelating agent, Humic acid (HA), on to a microwave-assisted chemically activated powdered biochar of banana pseudo stem, (BPSC), results in an incorporation of functional groups like -COOH, -OH, -NH2. Textural and magnetic properties were analysed via FT-IR, XPS, BET, FESEM, AFM, TG, DTA, VSM, XRD and CHNS analyser. The adsorption capacity and efficiency of γ-BPSC/HA adsorption were 34.25 mg/g and 98.5%, respectively. By using XPS analysis, it was confirmed that the adsorbent's metal ions were bound to specific binding sites and had a specific capturing mechanism. A mechanism of spontaneous complexation was accomplished, because of the heterogeneity of the surface, electrostatic forces, pore filling, H-bonding, and π-π stacking. Follows PSO kinetics and favours Freundlich isotherm. The adsorbent substance shown a remarkable capacity for regeneration, assuring the substance's stability and reusability.

Critical Analysis of Stakeholders in the Municipality of Tarija, Bolivia, in Search of Strategies for Adequate Water Governance to Implement Reverse Osmosis as an Alternative for Generating Safe Water for Its Inhabitants

The accelerated deterioration of water quality in the city of Tarija, Bolivia, has caused several water sources in the Municipality of Tarija to be discontinued due to the presence of toxic contaminants. The current water purification systems that are used in Tarija do not guarantee the elimination of heavy metals; in addition, political and social interest conflicts are a serious problem in the execution of projects and new public investment alternatives, with these being the main problems found in the sector. Reverse osmosis (RO) water purification technologies are one of the most effective contemporary alternatives for the elimination of contaminants in water, such as heavy metals; however, their application and implementation in countries with little or no experience in this type of technology require acceptance and knowledge on behalf of the interested parties. Political and social conflicts between interested parties generate scenarios that affect hydrological planning. Analysis of the actors in the urban and municipal sphere of the city of Tarija, Bolivia, provides a case study for adequate water governance and enabled us to come to a consensus for the implementation of RO. The results show 23 fundamental actors in water management in the Municipality of Tarija, with local actors being those with the greatest influence and power in decision-making. Our analysis of social networks showed an important polarization in the power of decision makers, with municipalities and legislative entities being those that decide on public investments. The interested parties showed considerable interest in the application of RO as a technology that can provide definitive, short-term solutions to the problems of water stress and the water crisis in the Municipality of Tarija and its application in small towns with a high level of social and environmental vulnerability.

Microplastic in industrial aquaculture: Occurrence in the aquatic environment, feed and organisms (Dicentrarchus labrax)

The increasing use of plastics and the growing concern about their impact on the environment and living beings makes it necessary to study how microplastics (MP) affect aquaculture systems. In order to gain an in-depth understanding of these systems, this study covers the water intake, the purification treatment at the inlet, the water in the culture tanks, as well as the feed used in the feeding and the organism itself. For this purpose, five samples were taken, both in the water line, feed and sea bass during the weeks of the experiment. It is shown that the available purification systems reduce the amount of MP entering from the receiving environment. However, new MP are observed in the sea bass tank, which may be due mainly to those added through the feed and found in the feed, as well as in the piping and other materials used in current aquaculture systems (PTFE, PA, among others). If focusing on the feed that can reach the consumer, in the case of this study, carried out with sea bass, some types of MP (PE, PTFE, PS and PA) were found in 4 head samples and 4 skin/muscle samples. Although inlet water purification systems manage to reduce a high percentage of MPs in the system, it is observed that there are other access routes that should be considered and reduced in aquaculture facilities to prevent them from reaching the human consumer.

Fabrication of gelatin-incorporated nanoporous chitosan-based membranes for potential water desalination applications

Membrane technology has extensively been used in diverse phenomena such as separation, purification and controlled transportation. Herein, gelatin-incorporated porous chitosan membranes have been prepared using the sol-gel approach for potential water desalination applications. The porogens of poly(ethylene glycol) and Triton X-100 were employed for the mentioned purpose. The prepared porous membranes have been characterized for surface chemical, structural, thermal, mechanical and functional attributes using appropriate analytical approaches. Electron microscopy expressed porous surface morphologies of the resultant films with an average pore size of 14.5 nm. The infrared analysis demonstrated a successful crosslinking of the precursors in the resulting membranes via maleic anhydride. Differential scanning calorimetry analysis disclosed acceptable thermal stability of the test membranes, workable above ambient temperatures. The membrane expressed a water contact of 68.59°, which indicated moderate hydrophilicity, thus allowing controlled transport of the aqueous media. The resultant gelatin/chitosan porous membrane exhibited a porosity of 98 % against kerosene oil. In contrast, the flowability of 7.14 (ethanol), 5.00 (distilled water) and 0.53 (ethylene glycol) mL/min has been recorded against the mentioned liquids. The membrane efficiently purified the local canal water to permissible limits. Such membranes have been qualified for potential applications in water purification systems.

Çevre Dostu Karbon Nano Fiberlerin Kimyasal Buhar Biriktirme Tekniği Kullanılarak Metanol ile Sentezlenmesi

This study aims to investigate the suitability of methanol as a carbon source for the synthesis of carbon nanofibres (CNFs), currently used in wastewater, water, and air purification systems, by chemical vapor deposition (CVD) in the presence of NiO catalyst. Experimental studies were carried out in a tube furnace under isothermal conditions. Catalyst particles were loaded onto silicon wafers with orientation by dip coating to grow CNFs. The reduction behavior of nickel oxide powder at 1000 K under non-isothermal and isothermal conditions was investigated before CNF synthesis studies. The percentage reduction of nickel oxide powder under non-isothermal conditions was 82.03%. The percentage reduction under isothermal conditions for 30 min was 78.03%. The experimental result obtained is very close to the theoretical value (78.57%). During CNF synthesis experiments, it was observed that CNF formation was not achieved at temperatures of 1000 - 1100 K due to the poor thermal decomposition of methanol. Pyrolysis of methanol increased with increasing synthesis temperature (1200 K), which promoted the synthesis of CNFs. SEM analysis revealed morphologically dense CNF formation under isothermal conditions for 20 min at 1300K synthesis temperature.

Emerging micropollutants in aquatic ecosystems and nanotechnology-based removal alternatives: A review

There is a significant concern about the accessibility of uncontaminated and safe drinking water, a fundamental necessity for human beings. This concern is attributed to the toxic micropollutants from several emission sources, including industrial toxins, agricultural runoff, wastewater discharges, sewer overflows, landfills, algal blooms and microbiota. Emerging micropollutants (EMs) encompass a broad spectrum of compounds, including pharmaceutically active chemicals, personal care products, pesticides, industrial chemicals, steroid hormones, toxic nanomaterials, microplastics, heavy metals, and microorganisms. The pervasive and enduring nature of EMs has resulted in a detrimental impact on global urban water systems. Of late, these contaminants are receiving more attention due to their inherent potential to generate environmental toxicity and adverse health effects on humans and aquatic life. Although little progress has been made in discovering removal methodologies for EMs, a basic categorization procedure is required to identify and restrict the EMs to tackle the problem of these emerging contaminants. The present review paper provides a crude classification of EMs and their associated negative impact on aquatic life. Furthermore, it delves into various nanotechnology-based approaches as effective solutions to address the challenge of removing EMs from water, thereby ensuring potable drinking water. To conclude, this review paper addresses the challenges associated with the commercialization of nanomaterial, such as toxicity, high cost, inadequate government policies, and incompatibility with the present water purification system and recommends crucial directions for further research that should be pursued.

Biomass‐Based Materials for Sustainably Sourced Solar‐Driven Interfacial Steam Generation

Solar‐driven interfacial water evaporation powered by solar energy has gained significant interest as a sustainable and cost‐efficient desalination technology, owing to its zero reliance on fossil fuels. It aligns the relationship between freshwater demand and environmental‐friendly water yields and provides us with a feasible and effective way to mitigate the global water crisis. Biomass‐derived photothermal evaporators stemming from sustainable and renewable resources and performing high freshwater output have piqued researchers’ interest in achieving water evaporation effectively, economically, and greenly. In this review work, biomass‐based photothermal evaporators coming from hydrogels, carbides, and fibers are summarized and their optical design, wettability, thermal management, and salt‐rejection ability are analyzed, presenting an overview of the current status of biomass‐based materials in the solar‐driven water purification system.

Smart IoT-based water treatment with a Supervisory Control and Data Acquisition (SCADA) system process

Abstract Water treatment is necessary to ensure the availability of clean and safe water for various uses. Integrating Internet of Things (IoT) technology with water purification systems has shown enormous potential in recent years for enhancing the efficiency and efficacy of the treatment process. Monitoring the disposal of sewage in treatment facilities is the primary obstacle. As a result, a Supervisory Control And Data Acquisition (SCADA) system, including the IoT, has been proposed to ensure the proper operation of these sewer systems and limit the risk of overflow and malfunction. In this paper, we suggest a novel approach that blends Deep Belief Networks (DBNs) with an IoT-based water treatment system equipped with a SCADA system for increased monitoring and control. An IoT–SCADA system can be implemented at various wastewater collection and treatment phases. Secondly, incorporating DBNs enhances the system's predictive capabilities, enabling proactive maintenance and decision-making to prevent potential failures and optimize resource allocation. The proposed technique computes the efficacy of the effluent treatment facility and ensures that chemical emissions do not exceed permissible limits. Furthermore, Complex Event Processing (CEP) can be utilized to evaluate and analyze the massive influx of real-time data sets provided by IoT sensors.