Freshwater Production Research Articles

Synergistic rGO/MoS2 E-Shaped Evaporators: Efficient Solar Desalination and Water Purification via Enhanced Photothermal Conversion and Structural Optimization.

Solar-driven interfacial evaporation has garnered significant attention as a sustainable technology for freshwater production. However, its widespread application is impeded by challenges, such as complex fabrication processes, high costs, and vulnerability to pore clogging. Herein, we present an E-shaped evaporator constructed through in situ integration of a binary photothermal nanocomposite comprising reduced graphene oxide and molybdenum disulfide (rGO/MoS2) onto a polyurethane sponge substrate. The synergistic light absorption enhancement of the rGO/MoS2 hybrid is rationally utilized to achieve excellent broadband solar harvesting. The distinctive E-shaped configuration simultaneously optimizes light utilization through multiangle photon capture and facilitates rapid water transport via hierarchical channels. This integrated system demonstrates exceptional operational stability with a cumulative water yield of 16.58 kg·m-2 under 12 h natural illumination, which could effectively facilitate seawater desalination and wastewater purification. The proposed fabrication strategy, characterized by cost-effectiveness and scalable manufacturing compatibility, paves the way for practical implementation in off-grid water purification systems.

Thermodynamic and Thermoeconomic Analysis of a Multigeneration System Based on Solar Energy Using Nanofluid for Power, Fresh Water, Hydrogen, Heating and Cooling Production

In this study, the thermodynamic and thermoeconomic analysis of a multigeneration system which produces power, cooling, domestic heating, hydrogen and freshwater has been carried out. The main source of energy for this system is a solar parabolic trough collector (PTC). The working fluid applied for this solar collector is Al2O3-Therminol VP1 nanofluid. The subsystems of this multigeneration system are a steam Rankine cycle for power production, an organic Rankine cycle for power production, a double-effect absorption refrigeration system for cooling production, a domestic water heater for hot water production, a PEM electrolyzer for hydrogen production and a RO desalination unit for freshwater production. In the ORC cycle a TEG unit is applied instead of the condenser for extra power production. The system is analyzed by using the EES software. The effects of different parameters as well as the effects of nanoparticles on the performance of the proposed system were investigated. According to the results, the energy and exergy efficiency of the system are 33.81 % and 23.59 %, respectively. Among the studied working fluids in the ORC cycle, n-pentane shows the best performance. The energy and exergy efficiency of the system increases by the nanoparticle volume concentration and the solar radiation increase. Moreover, the collector inlet temperature has a negative effect on the hydrogen and freshwater production rates. Finally, it is proved that the PTC collector has the highest amount of exergy destruction rate in the studied system.

Optimizing a novel biogas-powered multi-generation plant: Thermodynamic, thermo-economic, and environmental evaluations for hydrogen, power, and freshwater production

Optimizing a novel biogas-powered multi-generation plant: Thermodynamic, thermo-economic, and environmental evaluations for hydrogen, power, and freshwater production

Black silver-coated cellulose paper for efficient and durable solar-driven desalination.

Black silver-coated cellulose paper for efficient and durable solar-driven desalination.

Based on PEG composite phase change material efficient of solar sustainable freshwater production

Based on PEG composite phase change material efficient of solar sustainable freshwater production

Advanced Multi-functional polyurethane sponge with excellent salt Resistant, Antifouling and Oil-Water separation capabilities for highly efficient and Persistent solar desalination

Advanced Multi-functional polyurethane sponge with excellent salt Resistant, Antifouling and Oil-Water separation capabilities for highly efficient and Persistent solar desalination

The Effect of Phase Change Material (PCM) on Efficiency and Productivity in Tubular Solar Distillation Using a Parabolic Trough Collector

This study investigates the effect of Phase Change Material (PCM) on temperature, efficiency, and productivity. The prototype solar distillation system is tube-shaped, with a length of 50 cm and a diameter of 4 inches, using a parabolic trough collector. The PCM used is beeswax, which is wrapped in aluminum foil. The results show that the use of PCM improves freshwater productivity. On the first day, the PCM method showed an 11% increase in production, and on the second day, freshwater production increased by 13%. The production rate with PCM was 0.76 L/m²/day, compared to the conventional method, which had a rate of 0.67 L/m²/day. The system with PCM also achieved high efficiency, reaching 11,47% on the first day and 13,9% on the second day. The system remained stable in the afternoon and evening, maintaining temperatures above 35 °C at night, compared to the system without PCM, where the temperature dropped to 30 °C. The use of PCM significantly enhanced the overall performance of the distillation system.

Fast Seawater Desalination Driven by Efficient Nitrate Reduction via Bimetallic Iron/Zinc Polyphthalocyanine Frameworks

Abstract Freshwater scarcity and nitrate contamination in water sources are critical environmental sustainability challenges. We address these two challenges by coupling seawater desalination with electrochemical nitrate reduction (NO3RR) via bimetallic Fe/Zn polyphthalocyanine frameworks. They serve as high‐performance catalysts for NO3RR toward ammonia (NH3) production. The efficient NO3RR is integrated into an electrocatalytic desalination device, enabling the production of freshwater from seawater and the removal of nitrate from contaminated water. In situ spectroscopic studies and theoretical calculations show that Zn‐N4 units incorporated into the Fe polyphthalocyanine framework modulate Fe‐N4 sites’ d‐band center to enhance the adsorption of NO3− and the generation of *H, resulting in 3.22 times higher turnover frequency and highly selective reduction toward NH3. The optimized Fe8Zn1PPc delivered NH3 Faradic efficiency (>97% over a wide potential range (−0.55 to −0.95 V vs. reversible hydrogen electrode (RHE)), the NH3 yield rate of 2.68 mmol h−1 cm−2 at −0.85 V versus RHE, and over 120 h of stable operation, outperforming previously reported Fe‐based catalysts for NO3RR. The desalination device achieves the highest salt removal rates (1326.92 µg cm−2 min−1) among various desalination methods. Ten cycles of natural seawater desalination to drinking water are demonstrated with 99% ion removal. This work presents an innovative solution for addressing sustainable water challenges.

Prevalence of foodborne parasitic infections in market-sold aquatic products and high-risk populations in Shanghai, China: surveillance between 2022 and 2024

BackgroundSubstantial achievements have been made in preventing and treating human parasitic diseases in China over the past six decades. However, with the recent progression of economic globalization and food diversification, foodborne parasitic diseases have become a significant public health challenge. Here, we investigated and analyzed the characteristics of foodborne parasitic infections arising from market-sold aquatic food products and in key populations.MethodsFreshwater, seawater, and pickled products were randomly obtained from agricultural trade markets, restaurants, supermarkets, and retail stores in four districts of Shanghai from 2022 to 2024. Parasite metacercariae or larvae were subsequently detected in these aquatic products via artificial digestion or dissection methods. Fecal samples from 698 diarrhea outpatients from the intestinal clinics of hospitals were analyzed via molecular methods.ResultsOf the 1,914 aquatic samples, 163 (8.52%) tested positive for parasites. Nine out of 1,086 freshwater products tested positive for parasites, including Clonorchis sinensis (7; 0.64%) and Gnathosotoma spinigerum (2; 0.18%). Anisakis was detected only in 7 of 27 seawater fish species, with contamination rates ranging from 6.00 to 100.00%. Echinostoma metacercariae was found only in marinated mud snails (20.43%). The prevalence of Clonorchis sinensis metacercariae in freshwater fish was highest in the second quarter (April–June), and catering samples presented the highest contamination rate, at 12.96%. In the sequence analysis, only one outpatient sample tested positive for parasitic infection, identified as Cryptosporidium meleagridis. No Giardia lamblia was found in the participants.ConclusionsFoodborne parasite contamination occurs in market-sold aquatic food products in Shanghai Municipality, although the incidence of parasite infection was low in the key populations tested. Further studies are needed to establish more comprehensive information that could improve public health and human food safety awareness.

HEAT AND MASS TRANSFER ANALYSIS OF INCLINED FLAT PLATE SOLAR STILL USING THERMAL CONDUCTIVITY ENHANCED WICK MATERIALS – AN EXPERIMENTAL APPROACH

Abstract Incorporating a thermal conductivity-enhanced wick fabric in the analysis of an inclined flat plate solar still [IFPSS] enhances heat and mass transfer. The improved wick material facilitates better absorption of solar radiation, leading to increased temperature gradients. This, in turn, enhances evaporation rates, contributing to higher freshwater production. In this experimentation, the performance of IFPSS is evaluated by inserting mild steel, aluminium and copper chips in jute cloth under actual geographical condition (latitude 17.0895° N, and longitude 82.0667° E) of Surampalem, Andhra Pradesh, India. Inclined flat plate configuration leads better exposure to solar rays and natural condensate flow. Integration of high thermal conductivity metal chips (copper, aluminum, mild steel) into the wick layer improves evaporation and condensation efficiency. The actual freshwater yield of the proposed system is in line with the theoretical productivity computed from the standard equation, with a deviation of just ± 9.60%. Additionally, the Sherwood number and Nusselt number predictions are put forth to verify mass transport and heat transfer, respectively. The system efficiency of Slot 4 is 8.5%, 21.42% and 30.76% greater than the Slot 3, Slot 2 and Slot 1, respectively. The percentage enhancement of daily productivity of Slot 4, Slot 3, and Slot 2 are 68.96%, 59.46% and 41.37% higher than Slot 1 respectively. This is because in Slot 4 copper chips whose thermal conductivity is high are incorporated with the Jute wick.

Fast Seawater Desalination Driven by Efficient Nitrate Reduction via Bimetallic Iron/Zinc Polyphthalocyanine Frameworks.

Freshwater scarcity and nitrate contamination in water sources are critical environmental sustainability challenges. We address these two challenges by coupling seawater desalination with electrochemical nitrate reduction (NO3RR) via bimetallic Fe/Zn polyphthalocyanine frameworks. They serve as high-performance catalysts for NO3RR toward ammonia (NH3) production. The efficient NO3RR is integrated into an electrocatalytic desalination device, enabling the production of freshwater from seawater and the removal of nitrate from contaminated water. In situ spectroscopic studies and theoretical calculations show that Zn-N4 units incorporated into the Fe polyphthalocyanine framework modulate Fe-N4 sites'd-band center to enhance the adsorption of NO3 - and the generation of *H, resulting in 3.22 times higher turnover frequency and highly selective reduction toward NH3. The optimized Fe8Zn1PPc delivered NH3 Faradic efficiency (>97% over a wide potential range (-0.55 to -0.95V vs. reversible hydrogen electrode (RHE)), the NH3 yield rate of 2.68mmol h-1cm-2 at -0.85V versus RHE, and over 120h of stable operation, outperforming previously reported Fe-based catalysts for NO3RR. The desalination device achieves the highest salt removal rates (1326.92µg cm-2 min-1) among various desalination methods. Ten cycles of natural seawater desalination to drinking water are demonstrated with 99% ion removal. This work presents an innovative solution for addressing sustainable water challenges.

Electrochemical Preparation of Graphene Membrane for Continuous Water Vapor and Crystalline Salt Production

Graphene has high application value in photothermal conversion fields because of the thinness, ultra‐lightness, and excellent photothermal properties. However, the traditional methods for preparing commercial graphene were less efficient and more expensive. Herein, the graphene suspensions were prepared using a convenient and environmentally friendly electrochemical exfoliation method. The graphene photothermal conversion (E‐GR) membranes were obtained to investigate the effect of electrochemical preparation conditions on the photothermal conversion performance. The evaporation rate of E‐GR membrane was 1.267 kg m−2 h−1 under 1 sun, achieving a solar‐to‐steam conversion efficiency of 79.65%. In the continuous salt crystallization experiment, the E‐GR membrane achieved desalination and uninterrupted fresh water and salt production for 7 days, resulting in the generation of 23.451 kg m−2 d−1 fresh water and 0.654 kg m−2 d−1 crystalline salt. During this period, the crystalline salt was formed only at the edges with no obvious crystallization on the surface. Because of the characteristic that graphene can provide a large number of adsorption sites, combined with the capillary action of filter paper, the membrane can be wetted in a short time. Overall, this simple, cost‐effective and efficient preparation method greatly promotes the application of graphene in the field of seawater desalination.

Solar-Driven Dual-functional Adsorvaporator Enabling Efficient Lithium Concentration and Freshwater Generation with Life Cycle Assessment Evaluation.

Solar vapor generation (SVG) has emerged as a sustainable and energy-efficient strategy for freshwater production and mineral extraction from brines. Here, the intrinsic water-salt ion transport characteristics of SVG are harnessed to develop a dual-functional "adsorvaporator"-an upcycled hybrid platform that seamlessly integrates simultaneous lithium adsorption/concentration and solar vapor generation. This adsorvaporator is constructed from a molybdenum disulfide (MoS2) photothermal components- and H1.33Mn1.67O4 (HMO) ion sieves- embedded acrylamide hydrogel (MHA) with anti-salt and saturated lithium adsorption capabilities, which can enable synergistic lithium recovery and high-performance water evaporation. Under 1-sun irradiation, the optimized MHA platform achieves a fast and stable evaporation rate of 2.13kg m-2 h-1 in a 20wt.% sea-salt solution, demonstrating exceptional long-term stability over 150 h. Additionally, a pioneering life cycle assessment (LCA) of this integrated system reveals significant environmental benefits, including drastic reductions in carbon emissions, energy consumption, and water usage compared to conventional lithium extraction methods. This comprehensive LCA confirms that the system operates with a substantially lower carbon footprint and water footprint, while also minimizing energy demand. The study introduces a scalable, eco-efficient solution for sustainable lithium recovery, offering a transformative pathway for resource circularity and renewable energy use.

Improving the Productivity of a Double Slope Solar Still by Integrating a PMMA Fresnel Lens: Experimental Approach

This study investigates the performance enhancement of a Modified Double Slope Solar Still System (MDSSS) through the integration of a polymethyl methacrylate (PMMA) Fresnel lens under the climatic conditions of Chengalpattu, India. The experimental setup evaluates the impact of solar concentration on basin water temperature, glass cover temperature, freshwater yield, and system efficiencies at three different basin water depths (10 mm, 20 mm, and 30 mm). The Fresnel lens was oriented in the north–south direction with tilt angles ranging from 0° to 60° to optimize solar capture. Results show that the incorporation of the Fresnel lens significantly increases basin water temperatures (by 8–10 °C), glass cover temperatures, and cumulative freshwater yield across all tested depths, with a maximum yield of approximately 6.0 L/m² recorded at 10 mm depth. Energy and exergy analyses reveal notable efficiency improvements in the lens-assisted configuration, with energy efficiency reaching up to 87% and exergy efficiency improving by up to 8% compared to the system without the lens. These findings confirm that the use of a Fresnel lens effectively boosts solar distillation performance by enhancing thermal energy concentration, particularly in systems operating with shallow water depths. The proposed enhancement offers a viable solution for increasing freshwater production in passive solar desalination systems.

Phase-Change Microcapsules Boosting Clean Water Production and Electricity Output through Janus Bilayer Poly(vinyl alcohol)/Chitosan Composite Aerogels.

To address two critical global challenges─clean water scarcity and energy poverty─an innovative Janus bilayer composite aerogel is designed as a single solar-driven platform for sustainable clean water production and electricity generation. This type of Janus bilayer aerogel was successfully fabricated with a hydrophobic upper layer comprising a poly(vinyl alcohol) (PVA)/chitosan (CS)/carbon black (CB) composite aerogel and a hydrophilic lower layer based on a PVA/CS/phase-change microcapsule composite aerogel. With such a Janus bilayer structure, the composite aerogel demonstrates efficient light absorption and superior salt-resistant performance by its upper layer and prominent latent heat-storage and water-transport abilities by its lower layer. More importantly, the introduction of phase-change microcapsules enables the lower layer of the developed bilayer aerogel to store photothermal energy absorbed by its upper layer, continually driving interfacial evaporation under insufficient solar irradiation conditions. Benefiting from these advantages, the developed composite aerogel-based evaporator shows a high evaporation rate of 2.23 kg m-2 h-1 under one-sun irradiation alone with good resistance to salt accumulation. Compared to a control evaporator without any phase-change microcapsules, the developed evaporator obtained an increase in the total mass change of 150% under dark conditions. Meanwhile, a thermoelectrical generator equipped with the composite aerogel exhibits an open-circuit voltage of 143.89 mV under one-sun irradiation alone with an elongated power output period of 30 min. With an innovative Janus bilayer structural design by combining a biodegradable PVA/CS aerogel with phase-change microcapsules and CB nanoparticles, this study represents a significant advancement in renewable energy utilization, particularly in sustainable water purification and hybrid energy systems. The developed Janus bilayer composite aerogel exhibits great application potential in highly efficient freshwater production and electricity generation under intermittent sunlight irradiation.

Experimental and computational insights into sustainable lithium recovery and freshwater production via CO2 hydrate-based desalination

Experimental and computational insights into sustainable lithium recovery and freshwater production via CO2 hydrate-based desalination

Syncretizing photovoltaic module and air gap membrane distillation for simultaneous electricity and freshwater production: A comprehensive 5E study

Syncretizing photovoltaic module and air gap membrane distillation for simultaneous electricity and freshwater production: A comprehensive 5E study

Exergoeconomic evaluation and optimization of a solar-powered polygeneration system producing freshwater, electricity, hydrogen, and cooling

Exergoeconomic evaluation and optimization of a solar-powered polygeneration system producing freshwater, electricity, hydrogen, and cooling

Thermodynamic analysis and optimization of an optimized geothermal-driven quadruple-production system for sustainable power, heat, freshwater, and hydrogen production

Thermodynamic analysis and optimization of an optimized geothermal-driven quadruple-production system for sustainable power, heat, freshwater, and hydrogen production

Enhancing freshwater production of pyramid distiller with sun tracking, triangle additional absorber, reflectors, and Nano-enhanced PCM

Enhancing freshwater production of pyramid distiller with sun tracking, triangle additional absorber, reflectors, and Nano-enhanced PCM