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In this experimental study, a porous material is used inside the pipes of the evaporator as the main heat exchanging device in the air conditioning cycle. The used porous material consists of stainless steel balls of different diameters. As a case study, refrigerant R454B, which is a drop‐in replacement to refrigerant R410A, is used as a working fluid in the air conditioner thermodynamic cycle. Four different porosities were used during the experimental tests; 100% (empty tube), 46%, 40%, and 33%. This study investigated the influence of variation of porosity as well as outside air temperature and refrigerant evaporation temperature on the cycle coefficient of performance, evaporation capacity, pressure drop, and power consumption during the compression process. Measured evaporation temperatures and indoor temperatures during tests were in the range of 1.5–12°C and 18–25°C, respectively. The use of porous material in the evaporation heat exchanger resulted in a considerable increase in the cycle evaporation capacity and coefficient of performance. Varying porosity from 100% to 33% resulted in an average percent increase of cycle evaporation capacity and coefficient of performance by 48.8% and 84.3%, respectively. Also, decreasing porosity from 100% to 33% resulted in an average percent increase in power consumption during the compression process by about 27%. An average percent increase of power consumption of compressor by about 25.9% is also reported, when evaporation temperature increased from 1.5°C to 12°C. Increasing outside air temperature from 27.1°C to 39.5°C resulted in decreasing evaporation capacity and coefficient of performance by 35.2% and 34.5%, respectively, and in increasing compressor power consumption by about 14.3%. A considerable pressure drop was recorded during the evaporation process when using porous material. The volumetric evaporation capacity, as well as compressor discharge temperature, are increased by increasing evaporating temperature and by decreasing evaporator porosity. The increase in air ambient temperature resulted in a considerable increase in refrigerant mass flow rate. [ABSTRACT FROM AUTHOR]

Use of oscillating heat pipes as a new component related to heat transfer has always been of interest for different technologies in recent years. A novel U-shaped structure is designed for the 3D-PHPs and this novel design creates a high performance device. In this experimental study, the thermal performance of a newly designed three-dimensional pulsating heat pipe with Fe3O4 nanofluid exposed to magnetic field under different heat inputs (0 W to 450 W). The results showed that the filling ratio of 50 % had better thermal performance. Our results indicated that the use of iron oxide nanofluid (Fe3O4) at 2 % mass concentration significantly improves the thermal performance of the pulsating heat pipe especially in 50 % filling ratio compared to pure water, which also showed that the improvement of heat transfer coefficient can be better by using corrugated evaporator under magnetic field. The results show that when the evaporator of 3D-PHP is exposed to a constant magnetic field, the thermal performance of the device improves significantly. The results showed that thermal resistance has been reduced 18 %, 20 %, and 25 %, respectively, for nanofluid with 50 % filling ratio and corrugated evaporator and under magnetic field compared to water. Compared to pure water operating fluid, application of nanofluid, magnetic field, and corrugated evaporator reduces the average heat resistance and increases the heat transfer coefficient. This investigation will promote the development of effective cooling for electronic devices. [ABSTRACT FROM AUTHOR]

The present work investigates the energy performance analysis of a heptad‐based multiple‐stage evaporator (MSE) under steady and transient conditions, integrated with different energy reduction schemes (such as steam split, feed split, and feed preheater). The steady‐state analysis was performed to optimize the steam economy subjected to the developed steady‐state energy models as the equality constraints. The simulated optimization is a maximization problem and is solved by Interior‐Point Optimizer and Gray Wolf Optimizer on two different platforms, GAMS and MATLAB, respectively. Further, transient and stability analyses were performed by developing and representing the nonlinear dynamic energy models to the state‐space representation using linearization. [ABSTRACT FROM AUTHOR]

The refrigeration system can be utilized with dual or multi-evaporator to meet the cooling needs at several vapor pressures with a single compressor refrigeration system. The evaporators utilized in these systems can take water or air to the desired low temperatures. The energy consumption of the compressor can be decreased and the system can be made more efficient by including an ejector in refrigeration systems with dual evaporator. Within the scope of this study, an experimental refrigeration system with an ejector and two evaporators, the first one (evaporator#1) sourced by air, and the second one (evaporator#2) sourced by water, were installed. The performance of the experimental dual-evaporator ejector system (DEES) was tested depending on the water temperature and mass flow rates passing through evaporator#2. The performance parameters of the system at several mass flow rates and water temperature were analyzed, and the ejector's impact on the system was determined. As a refrigerant in DEES, low GWP (global warming potential) R516A refrigerant was utilized. System performance was calculated for three different water mass flow rate values at several water temperatures passing through evaporator#2. As a result, it was determined that when the water temperature increased from 10°C to 30°C and the water mass flow rate was the maximum, the power of the compressor increases by 7.2%, while the total refrigeration capacity rises by 25.9%. The results showed that the coefficient of performance (COP) increased by 9.1%, 15.2%, and 16.5%, respectively, at m1, m2, and m3 mass flow rates with the increase in water temperature from 10°C to 30°C. Additionally, evaporation temperatures in the evaporator increased with the decrease of entrainment ratio (ER). Finally, it was determined that the impact of the change in ER values on the superheating degree temperatures was higher than the mass water flow rate values. [ABSTRACT FROM AUTHOR]

The sulfuric acid process is the dominant technology for lithium extraction from spodumene. However, this process generates huge quantities of waste residue and needs high-temperature pretreatment. The process can be optimized if other high-value elements are found in spodumene deposits, residual lithium can be recycled during mining and processing, and energy savings can be achieved. This paper evaluates the sulfuric acid process for lithium extraction from spodumene from an operational, economic, and environmental perspective. The integration of evaporators and crystallizers during lithium extraction and processing is also reviewed. Finally, further research opportunities for making the process more cost-effective are identified. [ABSTRACT FROM AUTHOR]

[Display omitted] • Inspired plant, a novel carbon fiber-based evaporator device comprised of carbon fiber bundles (CFBs) and perforated wood, is designed for solar steam generation. • Vertical CFBs can realize broadband efficient light absorption and effectively supply water, enabling the proposed evaporator to achieve a high evaporation performance. • The plant-inspired device with scalability, feasibility, and low cost opens an avenue for designing and developing high-efficiency interfacial solar evaporators. Solar interfacial steam generation technology has been recognized as a highly desirable way to relieve the shortage of freshwater resources. However, the preparation of a high-performance salt-resistant evaporator with a simple fabrication process is challenging. Herein, a plant-inspired device comprised of several carbon fiber bundles (CFBs) and perforated wood is designed. Vertical CFBs can realize broadband efficient light absorption, and the capillary force of microchannels between carbon fibers can effectively supply water. The perforated wood holds CFBs in place, and the buoyancy of wood keeps the entire evaporator afloat. Adjusting the fineness and height of CFBs can control the steam generation rate. In the experiment simulating one sun's illumination, the evaporation rate of the optimized plant-inspired device is able to stabilize at 1.70 kg m−2h−1 and can effectively avoid salt crystallization for long periods of simulated seawater evaporation (3.5% NaCl solution). Benefiting from the inherent characteristics of carbon fibers and wood, this device also exhibits ultrahigh chemical stability. This plant-inspired evaporator from carbon fibers opens an avenue for the manufacture of simple and high-efficiency interfacial solar evaporators. [ABSTRACT FROM AUTHOR]

[Display omitted] Although solar energy is promising for water purification, there is still a room for further improving the solar steam generation efficiency. Herein, an environmental energy-enhanced solar steam evaporator is fabricated by immersing a cellulose acetate fiber-based cigarette filter (CF) in an aqueous solution of polyvinyl alcohol (PVA) followed by freeze-drying and decorating with MXene sheets. The presence of MXene is to absorb solar light and convert solar energy to thermal energy for efficient water evaporation, while the porous PVA network generated inside the pores of the filter during the freeze-drying process accommodates the dispersed MXene sheets and interconnects the CF and MXene. Because of the constructed PVA/MXene network inside the CF porous architecture and the hydrophilic feature of both MXene and PVA, the resultant MXene/PVA modified CF (MPCF) is highly hydrophilic and competent for rapid upward transfer of water. Interestingly, in addition to the normal energy input by the incident solar light, the large-area sidewall of MPCF gains thermal energy from the environment in the forms of heat convection and heat radiation to enhance the solar steam generation efficiency, resulting in an ultrahigh water evaporation rate of 3.38 kg m−2 h−1 with an outstanding evaporation efficiency of 132.9%. [ABSTRACT FROM AUTHOR]

Introduction. The aim of the presented research was to substantiate the intelligent automatic control of the sugar juice evaporation with the subsystem for behavior prediction, which allows to determine the behavior of the automatic system. Materials and methods. The operation of the evaporator unit with system behavior prediction to regulate the sugar juice level was investigated. Capacitive level gauges were used as a sensor in the automation scheme of sugar juice level control. Pneumatic seat valves with a built-in throttle and an electropneumatic converter were used as actuators. Results and discussion. The use of neuro-fuzzy regulators occurs only in some specific cases of intelligent control of the evaporation process. There is no data comparing the use of intelligent regulators with classical ones and the possibility of combining several types of intelligent regulators, as well as clear means of predicting their work. Therefore, in the present study, a prediction method was used to compare methods to regulate the level of sugar juice in the evaporator. This made it possible to predict the behavior of the system during the formation of the control action and display the finished forecast on the operator's screen, which made it possible to increase the efficiency of the evaporative station. Statistical data on the behavior of the automation system contours in various operating modes were collected using intelligent and classical controllers, and a model was built to determine the operation of the evaporator using the local trend method and the modified algorithm of prediction. The advantage of this method is its easy and fast implementation, which does not require large economic and energy costs. The accuracy of the prediction model was 98% for the PID-controller, 95% for the fuzzy-controller and 96% for the neural network. The obtained model of the system prediction is stable because the absolute error does not change when dividing the time series into intervals. Conclusions. The proposed system of intelligent automated control of the evaporation of sugar juice with a modified prediction method based on local trends has an insignificant delay, while prediction is performed with high accuracy and stability. [ABSTRACT FROM AUTHOR]

• Experimental fault tests on a variable-speed heat pump charged with propane. • Experimental procedure to emulate evaporator fouling, compressor valve leakage, liquid line restriction and refrigerant overcharge. • Quantitative results of the fault effects for two different heat demands. • Trend chart of relevant features of the heat pump. The European heat pump market is growing every year as European legislation moves towards the use of natural refrigerants that have less global warming potential than conventional refrigerants. Even though heat pumps are very efficient, the appearance of hard-to-detect faults increases energy consumption. The present study emulated some of the most common faults on a variable-speed heat pump charged with propane. The faults tested were evaporator fouling, compressor valve leakage, liquid line restriction and refrigerant overcharge. The effect of these faults on performance and several heat pump features are described. Evaporator fouling was the fault with least COP degradation and compressor valve leakage with the most (7% and 56% COP reduction, respectively). The results are compared with the results from a comparable study. The heat pump covered the demand generated by nearly all the faults at the expense of increasing the power consumption. The features of each fault are summarized in a chart, which could be used as table for diagnosing faults. [ABSTRACT FROM AUTHOR]

Solar water evaporation technology has become one of the promising ways for seawater desalination by excellent energy capture and efficient solar-thermal conversion. However, some challenges still restrict its further industrial development, such as low flexibility, non-portability, and insufficient energy utilization, salt crystallization problems. In this work, hierarchical MoS 2 nanosheets coupled with MXene (MoS 2 -MXene) is constructed and formed into a film with foldability and portability for solar water evaporation. Improved evaporation rate (2.5 kg m−2 h−1) is observed due to enhanced energy capture from a folded 3D solar evaporation system. Meanwhile, the outstanding evaporation performance (3.2 kg m−2 h−1) is realized because of gradient heating from a hydrophobic MoS 2 -MXene@PF (MoS 2 -MXene@Paraffin) under one sun. During the evaporation of high-concentration NaCl solution (20 wt%), the hydrophobic layer is observed to become a salt crystallization site for salt generation. After long-term and multiple testing, no salt crystallization was found at the evaporation site, maintaining a stable evaporation rate. More interesting, MoS 2 -MXene@PF can be also succeeded as a solar thermal pack for storing heat through the phase change material paraffin (PF). This work provides a new solution to realize excellent energy capture for solar desalination and solar thermal storage. [Display omitted] • Hierarchical MoS 2 nanosheets coupled with MXene for efficient solar evaporation. • Improved evaporation rate (2.5 kg m−2 h−1) is observed due to enhanced energy capture. • The outstanding evaporation performance (3.2 kg m−2 h−1) is realized because of gradient heating. [ABSTRACT FROM AUTHOR]

R-134a distribution in an evaporator having two-row/six-pass configuration was experimentally studied with the inlet quality 0.2 and the outlet superheat 5°C. The mass flux was varied from 63 kg/m2s to 117 kg/m2s. The flow distribution generally followed the expected trend. The insert configuration (multi-hole or a single rectangular hole) affected only nearly passes. Furthermore, better liquid distribution was obtained for the single rectangular hole insert. The effect of tube protrusion depth was only significant at the first pass. As a result, flow distribution correlations obtained from the two-row/four-pass configuration predicted the two-row/six-pass configuration data reasonably well. [ABSTRACT FROM AUTHOR]

[Display omitted] • Develop a portable solar evaporator that can save storage space more than 78%. • Hyperstable plant fibers/chitosan aerogel is constructed without toxic cross-linkers/solvents. • The solar evaporator can endure tremendous and repeated compression over 100 times. • The evaporator is cost-effective and salt-rejecting, working well under various harsh conditions. • High evaporation rate of 1.38 kg m-2 h−1 and solar-to-vapor conversion efficiency of 84.27%. Solar interfacial evaporation is an effective zero-energy method for seawater desalination, and solar evaporator is the key component in this evaporation system. Despite a great deal of solar evaporators have been reported, the poor portability of large-scale evaporators as well as high costs and materials toxicity still restrict their applications. In this work, a portable solar evaporator was constructed with low-cost plant fibers from papermaking pulp, using a facile method in absence of any toxic cross-linkers and solvents. The evaporator exhibited excellent stability and flexibility, and endured tremendous and repeated compression over 100 times. A large-scale evaporator could be compressed to reduce storage space by 78%, which would be portable for individuals. The evaporator presented a high evaporation rate of 1.38 kg m-2h−1, and solar-to-vapour conversion efficiency of 84.27% under one sun irradiation. The portable solar evaporator was salt-rejecting, and worked well under harsh conditions of high salinity and different pH values. The entire material cost of this potable solar evaporator is approximately 1.75 U.S. dollar m−2, much lower than those of conventional solar evaporators. This study provides a new approach for preparing portable and cost-effective solar evaporator. [ABSTRACT FROM AUTHOR]

In response to escalating demand for renewable energy, solar thermal evaporation systems with solar energy utilization and freshwater production capacities have garnered attention, yet face challenges in improving solar energy conversion efficiency and freshwater generation rate. Liquid metal particles emerge as a promising solution for photothermal systems due to their localized surface plasmon resonance (LSPR), but the poor formability limits the application in solar thermal evaporation systems. Herein, we present an innovative ice-templated material extrusion for liquid metal inks in a shape-morphing 3D photothermal solar generator. The programmable in-situ "freeze-printing" establishes water transport channels within printed liquid metal structures, enhancing functionality. This process, coupled with cool evaporation surface and optimized water supply channels, yields efficient and sustainable solar-driven evaporation. The liquid metal-based aerogel achieves an impressive surface temperature of 62 °C (36.4 °C in water) under 1 sun. The 3D programmable "freeze-printing" not only reduces ink consumption but also enables the construction of spiral-shaped structures, increase the cool evaporation surface. The resulting solar generation device attains a remarkable evaporation rate of 1.736 kg m−2 h−1. By delving into the structural design to enhance heat conduction and water evaporation, we have deepened our understanding of the printability of liquid metal in 3D, paving the way for advancements in additive manufacturing and evaporation applications. This work establishes a foundation for designing high-performance next-generation solar generation devices to combat global water scarcity. • Manipulating the rheological behavior and solution stability of LM ink. • Controlling the optical-thermal properties and structural stability of LM aerogel. • Constructing water transport channels by programmable "freeze-printing" technology. • Construction of a 3D evaporator provides cooler evaporating surface for efficient water evaporation. • Excellent water evaporation characteristics (1.736 kg m-2 h-1) and good cycling stability (8 times). [ABSTRACT FROM AUTHOR]

Although solar interfacial evaporation stands as a promising application for seawater desalination, it has been scarcely studied for volumetric reduction of particle-containing wastewater. Taking inspiration from trees, this work presents a novel approach of root-based solar-interfacial evaporation for accelerated drying of slurries. By varying the total surface area of the roots, the water conduction rate was maximized under different intensities of solar radiation. The optimal setup displayed a high evaporation rate of 1.15 kg/(m2h1) under 1 sun irradiation. Additionally, the evaporator dried the slurry to 75 wt% solid concentration at this high evaporation rate. The setup could remove water further till solid concentration above 90 wt% in a total 40-h duration. The decrease in slurry evaporation rates observed at higher solid concentration was attributed to the break-up of continuous water capillary bridges present between the particles in the slurries. Long duration evaporation experiments for over 100 h of continuous operation displayed 75 % evaporation efficiency, underlining the feasibility of this setup for long-term usage. Large-scale outdoor experiments, scaling to 625 cm2, exhibited high evaporation rates comparable to the smaller setups, confirming the feasibility of this setup for large-scale volumetric reduction. • Root-based evaporator setup developed for accelerated drying of fine-particle slurries • Slurry dried to 75 wt% solid concentration at high water evaporation rate • Larger root surface area extended evaporation performance to a higher solid concentration. • Evaporator displayed continuous removal of water beyond 90 wt% solid concentration. • Evaporator exhibited volumetric reduction for over 100 h of continuous operation. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation (SDIE) is a promising technology for sustainable and efficient production of clean water, addressing the pressing issue of freshwater scarcity facing humanity. Given the high level of concern regarding this matter, it is crucial to continuously summarize the research achievements of predecessors to further advance SDIE technology. This review first discusses the key role of solar absorbers containing Group VIII elements, including Fe, Co, and Ni, in SDIE. Second, it explores strategies to improve SDIE performance, such as increasing light absorption, regulating water transport channels, implementing effective thermal management, and reducing the enthalpy of water evaporation. These strategies can effectively optimize the performance of the evaporator and improve energy utilization efficiency. Further, this review details the specific applications of SDIE technology in areas such as seawater desalination, wastewater treatment, and energy reuse. We aim to provide insights for developing stable and efficient SDIE systems, promoting their practical applications, and developing other potential applications. [ABSTRACT FROM AUTHOR]

The high vaporization enthalpy of water attributed to the strong hydrogen bonds between water molecules is limiting the performance of solar evaporators. This work demonstrates a deliberate attempt to significantly reduce the vaporization enthalpy of water through the introduction of weak water-amine hydrogen bond interactions in hydrogel evaporators. In this article, bio-based chitosan-agarose/multiwalled carbon nanotube hydrogel film evaporators (CAMFEs) exhibit larger vaporization enthalpy reduction with the presence of primary amine groups in chitosan. An interplay between vaporization enthalpy reduction and water diffusivity leads to an optimal ratio of chitosan to agarose = 7:1 (CAMFE7) showing an impressive evaporation rate of 4.13 kg m−2 h−1 under 1 sun irradiation. CAMFE7 also exhibits excellent salt resistance, with a stable water evaporation rate, using brine water of up to 10 % salinity under continuous 1 sun irradiation. The high mechanical robustness together with its scalability makes CAMFE7 a highly promising material for practical drinking water production. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A low-energy hybrid FO-SE process was designed to desalinate brackish water. • An excellent PPy@MS solar evaporator is prepared by mixing in one step. • The structure–activity relationship of concentrating DS with PPy@MS was studied. • Evaporation link reversed the attenuation trend of J W at some DS concentrations. • Significant irreversible deterioration of J S and FO fouling did not formed. The application of the osmotic pressure-driven forward osmosis (FO) process is limited due to the high costs for regeneration and replacement of draw solution. A hybrid FO-solar evaporation (SE) hybrid process was systematically investigated to produce fresh water from desalination of brackish water. The melamine sponge loaded with polypyrrole (PPy@MS) composite material was synthesized by loading light-absorbing polypyrrole (PPy) into a network of melamine sponge (MS) substrates. As a solar evaporator, PPy@MS material showed high light absorption, water evaporation, and anti-pollution abilities in the FO-SE process. Feasibility for operating the hybrid desalination process was studied in terms of solar evaporation rate, salinity tolerance, hydrophilicity, and mechanical strength of PPy@MS, and desalination performance, including water flux, ion removal, reverse salt flux, and membrane fouling. Characterization results indicated that PPy@MS performed a high interfacial molecular transformation, solar energy accessing ability, salt-tolerance, and mechanical stability in a long-term FO-SE operation, achieving an evaporation rate up to 2.80 kg·m−2·h−1 (1 sun, 1 h) and ion removal rate of 99.9 %. A maximum evaporation flux of 17.4 L·m−2·h−1 was monitored in the FO-SE process using 2 M NaCl as the draw solution (FO film area: 5 cm2). Solar-driven evaporation via PPy@MS was able to assist the continuous operation of the FO-SE process with high water flux. This work proposes a novel sustainable hybrid FO-SE technology for FO desalination of brackish water and other saline water bodies. [ABSTRACT FROM AUTHOR]

In emerging supercritical energy systems like Organic Rankine cycle and Brayton cycle, the evaporator where supercritical fluid is heated is often horizontally placed. Accurate prediction of supercritical heat transfer coefficients is the basis of the heat exchanger design. However, existing correlations for horizontal supercritical flow were primarily for cooling condition, and though a few correlations were developed under heating condition, the thermal boundary was uniform heat flux instead of the convective boundary condition in practical applications. This work focuses on the design method of horizontally arranged supercritical evaporators, and explores the predictive capabilities as well as the limitations of existing correlations. On the basis of the general axial-segmented approach, circumferential segments were considered to account for the buoyancy effect in horizontal flow. Results show that all 8 correlations considered have certain limitations, overestimating or underestimating the heat transfer capacity depending on the heat flux and mass flux. The Krasnoshchekov and Protopopov correlation exhibited the highest predictive capability, accurately capturing 93.3 % of the 105 experimental CO 2 cases within a 5 °C error in outlet temperature. The newly introduced circumferential segments led to improved performance, especially when mean wall temperature was used to calculate average heat transfer coefficients. Finally, this work revealed the paradox between 'convergent' and 'optimal' solutions in the segmented approach, and discussed the issue of multiple solutions during the calculation of wall temperature and heat flux. • We studied the segment approach for the design of evaporator at supercritical state. • Nusselt correlations developed under various thermal boundaries were evaluated. • Correlations basing on circumferential average T w perform best against test database. • The circumferentially segmented approach improves prediction accuracy. • The issues of convergent and multiple solutions can bring great uncertainties. [ABSTRACT FROM AUTHOR]

Finned-tube heat exchangers are extensively used in industrial and daily life. As complex system designs and digital twins increase, higher demands arise for predictive modeling of finned-tube heat exchanger performance. Previous studies faced issues like disparities in evaporator performance under dry and wet conditions, inaccurate predictions of refrigerant pressure drop, and a lack of comprehensive consideration for predicting the trends in physical details. With the evolution of AI algorithms, exploring novel modeling methods becomes essential. Therefore, this study proposes a physics-informed deep residual network model for accurate performance prediction of finned-tube evaporators. The model achieved mean absolute error of 0.14 % for heat transfer rate prediction, 0.36 % for refrigerant pressure drop prediction, and 0.49 % for air pressure drop prediction. This model addresses previous issues of performance disparities under dry and wet conditions and high errors in refrigerant pressure drop prediction. The proposed deep residual network model is found much better performance in capturing physical details than other machine learning approaches. It can serve as a benchmark model for transfer learning or complex system modeling. The method of determining the structure of residual networks through a priori physical knowledge also provides a new perspective on modeling physical systems. • A ResNet model with prior physical knowledge is developed for finned-tube evaporator. • A cascade network with enhanced input improves refrigerant pressure drop prediction. • It predicts heat transfer and refrigerant pressure drop with MAPE of 0.14 % and 0.36 %. • It captures more accurate physical details than other machine learning methods. • It can serve as benchmark model for transfer learning or complex system modeling. [ABSTRACT FROM AUTHOR]

[Display omitted] • A contactless 3D Janus evaporator with core@shell structure was designed. • The combined function allows the core@shell Janus evaporator to maintain a high evaporation rate of 2.77 kg m−2h−1. • The core@shell Janus evaporator achieved efficient salt-collecting solar desalination. • The 3D Janus evaporator realized efficient seawater desalination and wastewater purification. Solar interfacial evaporation is a low-cost strategy for desalination and water purification. However, for most evaporators, the coplanar configuration of light absorption and water evaporation results in a confined evaporation surface and salt deposition problems. Here, a contactless 3D Janus evaporator (Ag-NSP@BFP) with a core/shell structure is designed by wrapping Ag nanoparticles (Ag-NPs) decorated nickel sponge (Ag-NSP) using bamboo fiber paper (BFP). The superhydrophobic Ag-NSP core (absorber) achieves highly efficient light absorption and photothermal conversion. Meanwhile, the superhydrophilic BFP shell not only provides a larger evaporation area (side surfaces as evaporation surfaces) but also forms a 2D water channel to ensure sufficient water supply. Furthermore, polystyrene foam (EPS) isolates photothermal material from bulk water, minimizing heat transmission losses dramatically. The 3D Janus evaporator increases the evaporation area and harvests energy from the ambient environment, achieving an evaporation rate of up to 2.77 kg m−2h−1 and an energy conversion efficiency of 105.2%. Moreover, the Janus structure effectively inhibits salt accumulation on the photothermal surface and exhibits a good purification effect on wastewater containing dyes and heavy metal ions. Thus, combining a 3D evaporator with Janus structure to achieve efficient salt-resistant evaporation provides a new design idea for stable seawater desalination and wastewater purification. [ABSTRACT FROM AUTHOR]

The solar-driven interfacial evaporation (SDIE) is a clean and efficient technology to mitigate freshwater shortages. A robust and low-cost evaporator is essential for the practical implementation of SDIE systems. Herein, we design a fantastic blended-fiber-based evaporator using weaving techniques. This mixture fabric is crafted using polyethylene terephthalate fibers and linen threads. It makes full use of the excellent light absorption, tensile strength, and corrosion resistance of polyethylene terephthalate fibers. Meanwhile, the mixture fabric reserves exceptional air permeability and water supply capability of linen thread. We optimize the density of the mixture fabric by adjusting the reed count and the weft count. It is found that the combination of the 40 reed and a single weft yarn produces the most effective and stable evaporator. The optimized mixture fabric makes a good trade-off between the water supply to the evaporator and solar-thermal evaporation. As a result, the evaporator achieves a high evaporation rate and efficiency (~ 1.53 kg / m 2 / h , ~ 90%) under 1 sun illumination, which surpasses most of the existing two-dimensional evaporators based on metal nanomaterials, polymers, carbon-based materials, and fabrics. Our work opens a new horizon for the development of efficient, scalable, flexible, low-cost, corrosion-resistant, and stable evaporators. • The cost of the blended-fiber-based evaporator is controlled ~ $2.21/m2. • The evaporator takes advantage of the excellent properties of polyethylene terephthalate fibers and linen threads. • A good trade-off between the water supply and solar-thermal evaporation is realized. • The evaporation rate and efficiency surpass most of the existing two-dimensional evaporators. [ABSTRACT FROM AUTHOR]

Solar interface evaporation technology has gained significant attention in the field of seawater desalination due to its environmentally friendly and sustainable characteristics. However, the efficient and stable application of solar evaporators still presents challenges in terms of material and structural design. The wood solar evaporator offers a promising solution as it meets the requirements of cost-effectiveness, ease of preparation, and environmental friendliness by utilizing the inherent channel structure of wood for seawater desalination. The paper introduces the structural principle of an Integrated Solar Still-Greenhouse (ISSG) system and highlights the advantages provided by wood solar evaporators within this system, including their unique wood hole structure and excellent thermal insulation performance. Additionally, various common methods for preparing wood solar evaporators are summarized (such as surface carbonization, coating deposition, wrapping, impregnation). Emphasis is placed on discussing the structural design of wood evaporators along with strategies for adjusting their functionality and stability. Finally, this paper addresses challenges faced by wood evaporators while suggesting future development directions that offer novel insights. • The working mechanism of solar interface evaporator is summarized. • The application of wood in solar energy evaporator is described. • The efficient preparation methods of wood solar evaporator are reviewed. • The stability and multifunctional application of wood evaporator are described. [ABSTRACT FROM AUTHOR]

Interfacial solar steam generation is acknowledged as an extremely effective and environmentally friendly method of producing potable water. Nevertheless, significant challenges persist in the development of an evaporator capable of achieving heightened rates of evaporation, catalytic capabilities, resistance to bacterial proliferation, and effective light absorption across a broad spectrum. This article outlines the fabrication of a solar steam generator utilizing electrospinning technology and membrane evaporators constructed from α-Fe 2 O 3 /PAN (polyacrylonitrile) nanofibers. The integration of α-Fe 2 O 3 /PAN composite enhances both light absorption and heat generation. In sunlight, the maximum evaporation rate is 2.7 kg m−2 h−1, which is significantly more than the rate of today's cutting-edge solution-electrospun nanofiber-based evaporators. The electrospun mat has high catalytic activity and antibacterial properties, making it an important component in desalination. [ABSTRACT FROM AUTHOR]

Solar-driven zero-liquid discharge (ZLD) is a promising wastewater management strategy for freshwater recovery and solid waste harvesting. However, practical application of the solar-driven ZLD is severely constrained due to its low evaporation efficiency, large footprint, and rapid salt accumulation. Here, we present a Janus arch-shaped solar-driven evaporator (▪) comprising a hydrophobic top photothermal layer for effective light absorption, solar-thermal conversion, and vapor evaporation, which exhibits an evaporation rate of 2.82 kg∙m−2∙h−1 in pure water. The design also includes shapable delignified longitudinal wood (D-L-wood) serving as the hydrophilic bottom water transport layer, which enables dual-directional saltwater transportation and salt crystallization. D-L-wood, with numerous aligned channels, exhibits a low thermal conductivity of 0.04 W·m−1·K−1 along perpendicular direction and can effectively localize heat on the photothermal layer of the evaporator. D-L-wood has excellent hydrophilicity, and the salty water can be transferred quickly along both ends of the wood, providing sufficient salty water for rapid evaporation. The anisotropy of the wood makes the heat transfer quickly along the channel, improving the thermal management ability of the evaporator. Moreover, during vapor evaporation on the hydrophilic-hydrophobic interface, salt is crystallized at the hydrophilic layer, resulting in an enhanced anti-salt performance, a 1.5 folds evaporation rate compared with non-Janus evaporator after 15 h test. Under the conditions of a salt concentration of 3.5 %, a high salt harvest performance of 62.4 g∙m−2∙h−1 can be obtained under AM 1.5 solar irradiation. The arch-shaped design fully utilizes the upper space and effectively reduces evaporator footprint, resulting in an evaporation area to footprint ratio of 1.57:1. The designed evaporator can also be utilized for ZLD treatment of other heavy metal polluted water including Cu2+, CrO 4 2−, Co2+, and so on. Therefore, the Janus-arch-shaped, solar-driven evaporator enables a potentially low-footprint, low-cost, scalable, and practical ZLD strategy for sustainable wastewater treatment. [Display omitted] • Elastic, Janus 3D delignified longitudinal wood evaporator with arch-shaped design is fabricated. • A high evaporation rate of 2.82 kg·m−2·h−1 is achieved, and the salt collection rate is 62.4 kg·m−2·h−1. • Salt is observed to crystallize on the bottom of the evaporator during the desalination process. • The arch structure reduces footprint and improves water transmission capacity. [ABSTRACT FROM AUTHOR]

The evaporator curvature can affect the heat transfer performance of two-phase closed thermosyphons (TPCTs) in permafrost regions. To explore the working features and control performance of TPCTs with different evaporator curvatures, two types of TPCTs with horizontal and inclined evaporator were designed. Then, a series of scale embankment models were conducted to test the thermal and deformation performance of the two TPCTs, including a TPCT embankment with inclined evaporator, a TPCT embankment with horizontal evaporator, and a contrast embankment without TPCTs. The results show that the thermal regulation performance of the TPCT with horizontal evaporator is much better than that with inclined evaporator. The thermal regime difference caused by the vapour-liquid interface interaction occurs in the whole pipe domain above the liquid pool for the TPCT with inclined evaporator while it mainly exists in the condenser domain for the TPCT with horizontal evaporator. Meanwhile, the TPCT with horizontal evaporator can decrease the temperature gradient, and thus weaken the frost heave of the embankment. Consequently, the TPCT with horizontal evaporator is more appropriate to adjust the local non-equilibrium heat process in embankment. The findings of this study supply a scientific reference for the design of TPCTs embankment in permafrost regions. • Effect of evaporator curvature of thermosyphon on its performance is investigated. • Isothermality of the thermosyphon with horizontal evaporator is more excellent. • Flow patterns in thermosyphons with different evaporator curvatures are proposed. • Themosyphon with horizontal evaporator is appropriate for non-equilibrium heat regulation [ABSTRACT FROM AUTHOR]

• A uniform wick suffers from degradation of performances with high load heat. • A bilayer wick design presents an alternative solution to that issue. • The bilayer wick with interconnection diameter gradient present slightly better thermal performance compared to a uniform one, without changing the total porosity. • The bilayer wick with pore diameter gradient presents the highest heat transfer coefficient and leads to the best results. In order to enhance the thermal performance of two-phase fluid loop devices, the purpose of this study is to investigate the benefit of using a bilayer wick in a capillary evaporator. In a homogenous wick, the porous structure characteristics present an intrinsic competition between increasing the capillary forces and reducing the pressure drop. Our investigation focuses on studying heat and mass transfer in uniform and bilayer ceramic wicks with the same porosity. The findings highlight the interest of a bilayer ceramic wick with a pore diameter gradient. This configuration exhibits heightened capillary pumping without compromising liquid pressure drop, leading to improved thermal performance in the evaporator. Our results demonstrate that opting for a bilayer ceramic with a pore diameter gradient can save up to 25 °C at the casing temperature and reach up to 1430 W/m²K−1 as heat transfer coefficient for a 70 W heat load value. [ABSTRACT FROM AUTHOR]

Solar vapor evaporators in saline hold enormous potentials in resource sustainability, seawater desalination, as well as renewable energy harvesting. Nanocomposite hydrogels with the property of photothermal conversion have emerged as candidates for solar-driven steam generation devices, but are limited by remote control and low mechanical properties in a saline environment. Here, we developed a remote-controlled, saline tolerant, and tough-yet-strong solar vapor evaporator based on multifunctional Fe 3 O 4 nanoparticles reinforced gel-nacre. The Fe 3 O 4 nanoparticles play triple roles of acting as nano-crosslinks, photothermal converters, and untethered manipulation, coupling gel-nacre matrix with a shrinking tendency in saline that contributes to synergistic mechanical reinforcement. Such integrated magnetic nanocomposite hydrogel exhibits tough-yet-strong mechanical properties (19.58 MPa ultimate strength, 300 % failure strain, self-recoverability under 500 %, and fatigue-resistance), addressing the challenges of remote operation system and high strength requirement for practical applications. Moreover, good photothermal conversion performances (1.26 kg m−2 h−1 evaporation rate and 92.84 % evaporation efficiency) could be achieved with remotely controlled motion or adjustable position simultaneously under an external magnetic field. The intelligent solar vapor evaporation system based on multifunctional magnetic Fe 3 O 4 @gel-nacre nanocomposite provides new opportunities for flexible energy-transducing devices with untethered manipulation in saline environment. [ABSTRACT FROM AUTHOR]

Interfacial solar desalination (ISE) emerges as a promising strategy to tackle the worldwide freshwater shortage. However, developing cost-effective solar evaporators that demonstrate exceptional evaporation rates while maintaining high salt-resistance is a tremendous challenge. This study introduces a three-dimensional (3D) solar evaporator, referred to as PPy-WMS, which is developed by employing a straightforward solution reaction to decorate polypyrrole (PPy) onto a waste mop sponge (WMS). The 3D PPy-WMS solar evaporator can capture ambient energy. When the exposure height is 6 cm, the PPy-WMS achieves an exceptional evaporation rate of 3.66 kg m−2 h−1 under 1-solar intensity. The macropore structure in WMS promotes water transport and facilitates salt ions backflow, resulting in high salt-resistance. The evaporation rate maintains at 2.91 kg m−2 h−1 when desalinating simulated seawater (20 wt%). Outdoor desalination experiments exhibit that 1 m2 of PPy-WMS can extract about 15 kg of freshwater per day. This economical and straightforwardly designed solar evaporator exhibits outstanding salt-resistance, presenting a viable remedy to address global freshwater scarcity. [Display omitted] • PPy-WMS with an exposure height of 6 cm achieves an excellent evaporation rate of 3.66 kg m−2 h−1. • PPy-WMS with a macroporous structure can resist 20 wt% simulated seawater with an evaporation rate of about 2.91 kg m−2 h−1. • 1 m2 PPy-WMS-6 can extract about 15 kg of freshwater per day. • PPy-WMS is cost-effective, performance-stable and durable. [ABSTRACT FROM AUTHOR]

Fresh drinking water and energy are crucial for the human society to live in a sustainable way, and both of these could be attained from the seawater. Herein, we designed a double-layered hydrogel evaporator (PCG@FCG) by using calcined carbon fiber derived from halfa grass (Desmostachya bipinnata) as a light absorbing photothermal material. The bottom hydrophilic layer composed of chitosan (CS), carboxy methyl cellulose (CMC), and amidoxime-modified chitosan (AOC), which helps in water transport to the upper surface of evaporator. The amidoxime modified chitosan helps in selective binding and recovery of uranium from the seawater. Such a judiciously designed PCG@FCG evaporator shows light absorbance of 96 %, stable evaporation rate of 2.0 kg m−2 h−1, having an outstanding selective uranium recovery of 325 mg g−1 under one sun irradiation. These outcomes result from the inherent structural porosity, enhanced evaporation rate, and selectively designed uranium binding sites. In addition, excellent salt-mitigating ability to promote uninterrupted evaporation, ability to purify the organic-contaminated wastewater/seawater endow the PCG@FCG evaporator with efficient seawater desalination ability and selective adsorption of uranium from the seawater. Overall, this innovatively-designed floating evaporator offers a sustainable approach to utilize the lavish resources in the seawater. [Display omitted] • A biomass photothermal hydrogel has been prepared. • An evaporation rate of 2 kg m−2 h −1 have been achieved under 1 sun. • The material shows an excellent uranium recovery of 325 mg g−1. • An evaporation rate of 1.78 kg m−2 h −1 was observed at salinity of 300 g.kg−1. [ABSTRACT FROM AUTHOR]

With the scarcity of freshwater resources, solar desalination of seawater is a promising strategy for freshwater production. Compared to 2D evaporators with limited evaporation area, 3D evaporators can increase the evaporation area. However, traditional 3D evaporators cannot fully utilize the internal space of the evaporator for evaporation. In this study, a 3D trapezoidal multi-interface evaporator (Evap1), which composed of superhydrophilic sponges and superhydrophobic sponges arranged by alternate permutation for making full use of the inside structure of the evaporator to expand the actual evaporation area and achieve effective thermal management, were developed. The selective water transport channels and heat transfer channels were constructed by alternate permutation of hydrophilic and hydrophobic sponges in Evap1, while the top trapezoidal structure prevented heat from accumulating on the top surface of Evap1, which can enhance the efficiency of photothermal conversion. The Evap1 exhibited excellent evaporation rate of 3.6 kg m−2 h−1 under 1 sun illumination, and the evaporation rate was almost unchanged in brine with 20 wt% concentration for 8 h working. In addition, the Evap1 can achieve efficiently purificaiton of waste water containing dye, and the potential practical application of Evap1 was further proved by repeated and outdoor evaporation experiments. • Multiple evaporation surfaces were constructed to enlarge evaporation area. • The 3D trapezoidal arrangement improved sunlight utilization. • The macro-structure design of the evaporator achieved good thermal management. • The evaporation showed excellent performance in high concentration seawater. • Providing a effective strategy for constructing 3D solar evaporation devices. [ABSTRACT FROM AUTHOR]

As for the evaporator of the large CAP1400 nuclear power plant, it has a large volume with numerous tubes along with the complex flow heat transfer phenomenon. The traditional direct simulation method usually takes a lot of time and computing resources to obtain the flow heat transfer data. To solve the problem, a fast simulation method established on the porous medium source term was herein proposed. In this simplified simulation method, the complex evaporator model is replaced with the porous medium model, where the derived heat and momentum source terms are added into the governing equation to control the heat flows. Five kinds of simplified evaporator models with different numbers of pipes were set to be the research objects, the internal flows inside the evaporator were studied with the traditional direct simulation method and the newly proposed simplified simulation method. Via comparative analysis, it can be found that: 1) The newly proposed simplified simulation method accurately captures the distribution characteristics of pressure, temperature, and entropy production in the evaporator, serving as a viable alternative to traditional direct simulation methods. Specifically, the average simulation errors for inlet-outlet pressure difference and temperature difference are both less than 5 % and 7 %, respectively. 2) The newly proposed simplified simulation method can capture the mutual interference effects between the evaporator and the nuclear main pump. When the evaporator is connected in series with the main nuclear pump, the average head of the main pump increases by 0.34 m, while the efficiency decreases by an average of 0.34 %. The average simulation errors of the simplified simulation method are 0.06 m and 0.13 %, respectively. 3) The application of the simplified simulation method leads to a significant 85 % decrease in the average computational cost for evaporator calculations and a notable 36 % decrease for combined calculations of the evaporator and main pump. The study here is expected to provide technique support for the simulation and evaluation of the large nuclear island. • A new fast 3D simplified simulation method based on the porous medium source term is proposed. • The accuracy of the new simplified simulation method is verified by analyzing the pressure, temperature, and energy loss. • Fast and accurate simulation of evaporators with complex tube bundles is realized. • The new simplified simulation method is applied to the joint simulation of the evaporator and nuclear main pump. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel mushroom-like evaporator with simultaneous freshwater production (70.2 %) and salt harvesting (42.1 g m−2h−1). • 7-day stable evaporation with evaporation rate of 1.88 kg m−2h−1 and efficiency of 99.4 % without salt contamination. • Edge-preferential crystallization due to capillary force, criss-cross water channels and gravity-assisted water transport. • Effective heat loss reduction due to low thermal conductivity as well as the vertical water upward transport. Solar-driven interfacial evaporation (SDIE) has emerged as a promising technology to alleviate the global freshwater scarcity. However, the simultaneous collection of water and salt as resources while maintaining stable evaporation rate without salt contamination at the evaporation interface remains a huge challenge. Herein, we report a novel mushroom-like cotton-based evaporator, inspired by the vertical stem and inclined caps of mushrooms, for simultaneous freshwater production and salt harvesting. By depositing polyaniline (PANI) and carbon nanotubes (CNTs) onto the cotton fabric (CF), an evaporation rate of 1.88 kg m−2h−1 and a high solar evaporation efficiency of 99.4 % can be achieved in 3.5 wt% NaCl solution under one solar irradiation. Furthermore, a significant water collection efficiency of 70.2 % and a high salt harvesting rate of 42.1 g m−2h−1 can be derived. Even exposed to high-concentration (15 wt%) brine, our design still effectively prevents salt contamination. The distinctive edge-preferential crystallization not only avoids the salt contamination but also promotes the salt harvesting, due to the capillary force, the criss-cross water channels from the nature of cotton cloth, as well as the gravity-assisted water transport of the "mushroom cap" during evaporation. In addition, the low thermal conductivity (0.163 W m−1 K−1) of the photothermal layer with the integration of PANI and CNTs, as well as the vertical water upward transport via the "mushroom stem" effectively reduce the heat loss. This research holds great potential for seawater desalination applications with the comprehensive utilization of seawater resources. [ABSTRACT FROM AUTHOR]

Cryogenic loop heat pipes (CLHPs) are widely used in satellites. To ensure the successful startup of a CLHP, the gas reservoir volume is typically designed to be 10 to 90 times larger than that of the CLHP itself. With the future miniaturization of satellites, it is crucial to reduce the total weight of the CLHP to lower the resources consumed on the thermal control subsystem. In this study, the relationship between the evaporation temperature of the secondary evaporator and the gas reservoir volume during the CLHP startup was theoretically analyzed. The validity of the relationship was demonstrated by comparing the theoretical results with the experimental data reported in the literature. Additionally, an ethylene charged CLHP with a gas reservoir volume of 3.6 times the CLHP volume was fabricated and tested. It was found that the CLHP can successfully start up by increasing the evaporation temperature of the secondary evaporator to 230 K, which agrees well with the theoretical calculation. The factors influencing the evaporation temperature of the secondary evaporator during the startup process were analyzed theoretically. A dimensionless parameter representing the minimum gas reservoir volume was established, which could guide the lightweight design of the gas reservoir volume. [ABSTRACT FROM AUTHOR]

As a convenient photothermal material, polydopamine (PDA) has been widely utilized in wood-based evaporators. However, the loading conditions of polydopamine on biomass bulk materials have not been systematically studied. In this paper, the suitable reaction conditions of polydopamine were studied with rattan as the substrate, and a reference for the improvement of the loading conditions was proposed. The polydopamine-loaded rattan-based evaporator (PDA-R) prepared on this basis exhibits excellent working stability due to the unique large-scale hierarchical porous structure of rattan. In addition to excellent salt resistance and cycle performance (evaporation rate decays by 5.1% after 30 cycles), the larger-aperture channel (200–450 μm) also brings better adaptability to salinity changes than polydopamine-loaded basswood-based evaporator (PDA-BW) (the attenuation coefficient of PDA-R is 6.2%, while the attenuation coefficient of PDA-BW is 16.3%). All of these indicate the broad prospects of polydopamine-loaded rattan-based evaporator as a multi-effect treatment scheme of brine. [Display omitted] • Loading conditions of polydopamine on biomass block material is systematic studied. • PDA-R has excellent salt resistance and cycling performance in high salinity brines. • PDA-R has great adaptability to salinity changes. • The effect of uniformly dense pore size of the substrate on salinity adaptability of evaporator is explored. [ABSTRACT FROM AUTHOR]

Solar evaporators are one of the most efficient and sustainable water purification strategies, but it requires the use of expensive photothermal materials. Herein, the surface of waste corn straw was modified with condensed lignin by means of in-situ lignin regeneration. The resulting material was composited with hydrophilic chitosan and then applied as a sustainable and cost-effective photothermal material to construct a solar evaporator. The non-radiative transport was conferred by π-π stacking between conjugated aromatic rings of lignin, allowing the composites to demonstrate promising photothermal conversion ability. The composites presented a max evaporation rate of ∼1.44 kg m−2 h−1 under 1 sun, plus they consistently produced clean water in aqueous organic dye solutions (100 ppm RhB dye and 100 ppm MB dye) and seawater. Due to the ultra-low cost of raw materials and uncomplicated manufacturing procedure, these composites displayed a cost-effectiveness of ∼475 g h−1 $−1. Thus, this work provides a green and sustainable method for converting agricultural waste into functional photothermal evaporators, which is meaningful for both materials and environmental science. [Display omitted] • The CS/LCS (x) composite aerogels solar evaporator were constructed. • Lignin regeneration enhanced photothermal evaporation performance. • The CS/LCS (x) composite aerogels offered remarkable cost-effectiveness. • Water purification in aqueous solutions of organic dyes and seawater. • Promising practical applications for water purification. [ABSTRACT FROM AUTHOR]

The escalating global freshwater crisis demands sustainable water management strategies, such as solar-driven interfacial steam generation (SISG). Three-dimensional (3D) photothermal evaporators emerge as a promising solution due to significantly higher evaporation rates compared to two-dimensional (2D) counterparts. This study described the design and fabrication of M-shaped 3D evaporators using the freeze-casting technique with graphite nanopowder (GNP) and polyvinylidene fluoride (PVDF). Under 1.0 kW m−2 solar irradiation and 4 m s-1 convective flow, a high evaporation rate of up to 10.5 kg m−2 h−1 in pure water was achieved. The M-shaped 3D evaporators demonstrated excellent performance in solar desalination and wastewater treatment, maintaining stability even in a 20 wt% sodium chloride (NaCl) solution at 1.0 kW m−2 solar irradiation and 2 m s−1 convective flow, with a rate of approximately 3.8 kg m−2 h−1. These findings highlight the significant potential for leveraging the synergistic interplay between solar energy and convective flow, which can be harnessed through the fabrication of customized 3D evaporators via freeze-casting. This innovative approach offers a scalable and cost-effective solution, contributing to both efficient water evaporation and environmentally sustainable high salinity desalination for future water treatment. [Display omitted] • The freeze-casting technique creates a graphite nanopowder-based 3D evaporator (GPE). • GPE utilizes convective flow, absorbing ambient heat for efficient water evaporation. • GPE can achieve a maximum water evaporation rate of 10.5 kg m-2 h-1 in pure water. • GPE keeps high performance during prolonged operation in highly concentrated brine. • Enabling an efficient, low-cost, tailored 3D evaporator for brine desalination [ABSTRACT FROM AUTHOR]

Seawater desalination based on air-water interfacial solar heating has attracted significant attention in recent years. However, the "high temperature, high salinity, sunlight irradiation and enrichment of photosensitive substances" environment formed at the evaporator surface unavoidably enhances the photochemical reaction, which in the next step may lead to the production of active species and by-products. In this work, H 2 O 2 , as an important reactive oxygen species and a transit substance for reactive oxygen species such as ·OH, 1O 2 , and ·O 2 −, was monitored during solar evaporation. The average H 2 O 2 concentration at the evaporator surface was 2.24 mg·L−1 with a maximum concentration of 5.0 mg·L−1, which is significantly higher than the average H 2 O 2 concentration in the ocean. The effects of the nitrate ions, halogen ions, iron ions, dissolved organic matter, and solar intensity on the generation of H 2 O 2 concentrations were explored. Finally, halogenated by-products were detected at the evaporator surface when phenol, a model pollutant, was present in the feedwater. This work fills the knowledge gap in understanding the generation of H 2 O 2 and the formation of halogenated by-products at the evaporator surface during solar evaporation. [Display omitted] • Photochemical reaction at the evaporator surface was enhanced. • H 2 O 2 with max concentration of 5.0 mg/L was generated at the evaporator surface. • H 2 O 2 concentration could be adjusted by tunning the solar evaporation conditions. • Halogenated by-products were detected at the evaporator surface. [ABSTRACT FROM AUTHOR]

This paper presents an evaluation of the energetic, exergetic, and exergoeconomic performances of a modified auto-cascade refrigeration (MACR) cycle integrated with a dual evaporator refrigerator (DER) to determine optimum operating conditions. DER facilitates a reduction in the compression ratio, allowing the low-boiling-point component to release more heat before entering the evaporator. In this study, the R170/R290 refrigerant mixture, which has a low global warming potential but an explosion risk, was used. The main purpose of this study is to eliminate the risk of explosion by reducing the compressor discharge temperature and at the same time to enhance the overall cycle performance. To achieve this, DER is used instead of air-cooled coils, which have limited cooling performance. Despite an ambient temperature of 35 °C , the MACR cycle achieved a remarkable 51.29 % reduction in compressor discharge temperature when the separator inlet temperature was reduced to 10 °C by the DER. It also results in a 72.73 % reduction in compression work rate and a significant 137.02 % increase in cooling effect compared to the conventional auto-cascade refrigeration cycle. Furthermore, the MACR cycle exhibits notable improvements in total exergy destruction rate and exergy destruction cost rate with a 75.23 % and a 76.07 % reduction, respectively. Simultaneously, the exergy efficiency and the exergoeconomic factor increased by 266.67 % and 179.15 % , respectively. The MACR cycle achieves optimum energy and exergy performance with a 60 % R170 mass fraction and 0.50 vapor quality, resulting in 1.429 k W compression work rate, a COP of 0.70, and an exergy efficiency of 26.66 %. The optimum exergoeconomic performance is achieved with a 40 % R170 mass fraction and 0.50 vapor quality. [Display omitted] • Energy, exergy, and exergoeconomic analyses have been conducted for the MACR cycle. • Optimum operating conditions have been identified. • Significant improvements are observed in discharge temperature and exergy destruction cost rate. • There is a notable enhancement in exergy efficiency and a substantial 179.2 % rise in the exergoeconomic factor. [ABSTRACT FROM AUTHOR]

In recent years, interfacial solar steam generation (ISSG) has been considered a potential solution to the current energy crisis and lack of freshwater. In ISSG, a novel solar interfacial evaporator is allowed to float on the bulk water. It has the ability to supply adequate water to the evaporative surface, suppress heat loss and improve light-to-vapour conversion efficiency. Since 2014, innovative photothermal materials as well as different types of advanced structural designed interfacial evaporators have been introduced in ISSG. This rapid development of evaporators has resulted in the evaporation efficiency of 100 % with least energy consumption. In this review, ultrahigh evaporation performance of ISSG with different types of solar evaporators (foam, wood, hydrogel, aerogel, membrane, 3D printing, paper and plant-based evaporators), fabrication process and vapour formation mechanisms are explored. After examining the latest technologies and advancements in research, potential methods to enhance the efficiency of ISSG under different levels of solar irradiation are described. Further, the challenges such as salt rejection technique, minimizing heat loss, water transport technique and condensation process are reviewed. Subsequently, the applications of ISSG in dye removal, water desalination, microorganism removal and power generation are explored. Eventually, the summary and outlook for improving this technology for real-world applications are summarized. [Display omitted] • We summarize the recent development of different types of solar evaporators. • Fabrication and vapour formation processes of different evaporators are reviewed. • Salt removal and other potential applications of ISSG are discussed. • We provide future suggestion to improve the ISSG performance. [ABSTRACT FROM AUTHOR]

Interfacial photothermal evaporation offers a promising and cost-effective method of obtaining freshwater. Traditional photothermal evaporators, when exposed to sunlight, typically have a heating region on their surface with temperature higher than room temperature. This can lead to thermal radiation loss and reduce evaporation efficiency. Therefore, this study presents an innovative design and fabrication of a fabric-based conical roll (FCR) evaporator, which enables low-temperature evaporation without a distinct heating region and facilitates the reversal of the thermal radiation path. In particular, the FCR-7.5-45 evaporator demonstrated remarkable performance even under 2.0 sun illumination, showcasing its advanced light-harvesting capability and excellent thermal management ability attributable to the conical spiral groove structure. The unique cold evaporation surface of the 3D evaporators, combined with this design, resulted in a high evaporation efficiency of 151.53 % and a rapid evaporation rate of 3.47 kg·m−2·h−1 under 1.0 sun illumination. Furthermore, the freshwater produced by the FCR evaporator met the drinking water standards set by international regulatory bodies. This indicates that the photothermal evaporator developed in this project holds great potential for widespread application in desalination and sewage treatment. [Display omitted] • A fabric-based conical roll (FCR) evaporator with 3D conical spiral groove structure design was successfully prepared. • The prepared 3D evaporator possessed advanced light-harvesting and thermal management design. • The evaporation rate and evaporation efficiency of FCR-7.5-45 were up to 3.47 kg·m−2·h−1 and 150.98 % respectively (1.0 sun). [ABSTRACT FROM AUTHOR]

Seawater desalination with solar-driven interfacial evaporators has emerged as a promising solution to alleviate global water scarcity. However, conventional two-dimensional (2D) planar evaporators have high reflectivity, which poses a challenge in achieving efficient light absorption. Herein, a sandwich-structured solar-driven interfacial evaporator (SSIE) assembled with three-dimensional (3D) cellulose aerogel membranes (modified with TiN nanoparticles) and an air-laid paper was proposed, which is significantly different from the previously reported 2D membrane-based evaporators. Cellulose aerogel membranes have excellent integrated properties, including extremely high flexibility, allowing for multiple folds, and a 3D porous structure that enables multiple light absorptions. Benefiting from special structural design, SSIE achieves an outstanding evaporation rate of 2.20 kg m−2 h−1 and an energy efficiency of 83.30%. Moreover, SSIE maintains a stable evaporation rate throughout a 10 h saltwater evaporation process. It also demonstrates excellent performance in seawater and simulated wastewater purification. Furthermore, SSIE exhibits a significant purification effect for dye wastewater, such as Rhodamine B (RhB). This study provides valuable insights into rational structural design for solar evaporators, as well as holding tremendous potential for carrying out seawater desalination in limited spaces. [Display omitted] • The 3D cellulose aerogel membrane achieves multiple light absorption to reduce energy loss. • The sandwich structure maintains a balance between water supply and evaporation and effectively impedes heat loss. • The SSIE has an evaporation rate of 2.20 Kg m-2 h-1 and an energy efficiency of 83.30% at 1 sun illumination. • The SSIE has achieved excellent results in seawater desalination and dye removal. [ABSTRACT FROM AUTHOR]

In this study, a Janus plasma carbonized film with asymmetric wettability was rapidly prepared within several minutes. It has shown great effects and considerable potential for desalination and wastewater treatment. [Display omitted] • A Janus plasma carbonized film (JPCF) for solar desalination is fast prepared by DBD. • Hydrophilic and hydrophobic surface regulation are concurrently achieved in one step. • JPCF achieves efficient evaporation and resistance of salt, oil, dye, acids, alkalis. • JPCF keeps high performance and long-term stability during the evaporation process. The conversion of biomass into desalination evaporators for the fresh water production has been proven a promising green strategy for the replenishment of fresh water resources. However, the primary challenges for the widespread application of such technologies are time-consuming, complex preparation processes and the stability of the evaporation interface. Herein, a novel biomass based hydrophilic/hydrophobic Janus structure plasma carbonized film material (JPCF) was prepared by dielectric barrier discharge (DBD) plasma. The preparation involved a short treatment time of 12 min after applying crylamide (AM) solution and sodium metasilicate nonahydrate (SMN) solution to different sides of a poplar chip. The evaporation rate of the prepared JPCF can reach 1.77 kg m−2h−1 in pure water and 1.75 kg m−2h−1 in 3.5 wt% NaCl solution under 1 solar irradiation. During a continuous evaporation of 14 h, the evaporation performance remained stable and no obvious salt accumulation appeared at the evaporation interface. More importantly, the JPCF showed an excellent purification ability to wastewater containing dye, oil, acids and alkalis. These key properties make the biomass-based Janus evaporator prepared by DBD plasma have a wide range of applications in desalination and wastewater treatment. [ABSTRACT FROM AUTHOR]

Interfacial solar steam generation (ISSG) is an emerging technology, used for the replenishment of water scarcity on the globe. In ISSG process, an interfacial evaporator is allowed to float on the bulk water surface to produce steam. Here, the different interfacial evaporators such as cotton cloth (CC), epoxy+hardener+sawdust (EHS) composite covered with cotton cloth (E-CC), EHS composite covered with Co 3 O 4 coated cotton cloth (E-CC/Co 3 O 4) and EHS composite covered with hybrid nanomaterial (Co 3 O 4 / NaTaO 3) coated cotton cloth (E-CC/hy1 and E-CC/hy2) are developed and experimented under 1 sun illumination. The synthesized NaTaO 3 and Co 3 O 4 photothermal materials are characterized using UV, XRD, FT-IR, FE-SEM, TEM and TGA respectively. Among all the evaporators, E-CC/hy2 attains an outstanding mass loss of water, evaporation rate and evaporation efficiency of 5.7 g, 4.92 kg m−2 h−1 and 117.78% respectively. In addition, the ion concentration of the condensed water is measured and found to be below WHO standards. Also, the dye degradation level of four different dyes is experimentally studied and found to be excellent dye degradation level for all the tested samples. The obtained results are mainly due to (i) the coating of Co 3 O 4 / NaTaO 3 composite over the top surface of the evaporator that traps the solar light efficiently (ii) the improved surface roughness that reduces the scattering and reflection of solar light (iii) the presence of excellent hydroxyl water absorbing groups in cotton cloth and better refilling of water at the evaporative surface of the evaporator (iv) low thermal conductivity of cotton cloth and EHS evaporator that inhibits the heat travel to the bulk water and glass beaker though conduction and convection. [Display omitted] • A low-cost perovskite structure based solar evaporator is fabricated. • mass loss of water, evaporation rate and efficiency are 5.7 g, 4.92 kg m-2 h-1% and 117.78%. • Salt removal at the evaporative surface is reduced due to the tortuosity effect. [ABSTRACT FROM AUTHOR]

The heat exchangers are essential components in the CO 2 heat pump-driven liquid desiccant dehumidification system since the heat transfer performance of heat exchangers directly affects the energy efficiency of the system. However, the heat transfer characteristics of CO 2 and liquid desiccant in the heat exchanger have yet to be fully revealed, resulting in a lack of appropriate strategies to improve the heat transfer performance. To address this issue, numerical gas cooler and evaporator models are developed and verified. The effects of parameters such as the weight concentration of the CaCl 2 aqueous solution, the CO 2 inlet pressure, mass flow rates, and the length of the heat exchanger on the heat transfer performance are investigated respectively under various operating conditions. Results show that the heat exchange load of the gas cooler can be significantly impacted by various inlet parameters of both fluids. In particular, the increase in the weight concentration from 36 to 54 wt.% deteriorates the heat exchange load by over 15 %. Nevertheless, the heat exchange load of the evaporator is hardly influenced by the weight concentration. This is attributed to a great gap in the two fluids' heat capacity rates, causing the evaporator to be in the maximum heat transfer state. The sign of the maximum heat transfer state of the heat exchanger is whether the thermal effectiveness is close to 1, which is related to the heat transfer area. Therefore, modifying the heat exchanger length could avoid the thermal effectiveness approaching 1. Results indicate that the appropriate length of the evaporator is 3–4 m under the designed operating conditions. • Heat transfer process for CO 2 and CaCl 2 aqueous solution is simulated accurately. • The heat transfer performance in the gas cooler and evaporator is investigated. • The evaporator is in the maximum heat transfer state in the designed condition. • The appropriate lengths of the gas cooler and evaporator are 14 m and 3–4 m. [ABSTRACT FROM AUTHOR]

• The Janus interfacial solar evaporator (SP-MF) is easily prepared by two-step impregnation approach. • SP-MF maintained at 1.78 kg m-2h−1 when 10 % brine was evaporated for 12 h under 1 sun. • SP-MF 1.68 kg m-2h−1 and 99 % evaporation rate and efficiency under 1 sun. • SP-MF can be applied to wastewater purification and seawater desalination. Herein, an integrated Janus evaporator with hydrophobic top and hydrophilic bottom was reported. The solar evaporator employs melamine foam coated with polypyrrole (PPy) as substrate, in which the PPy coating enhances light absorption, heat transfer, and steam release while preventing salt deposition due to its hydrophobic nature. The hydrophilic bottom of the evaporator was obtained by local modification with sodium alginate, promoting upward water transport and reduce heat loss. The evaporation rate of the integrated Janus evaporator was maintained at 1.78 kg m-2h−1 when 10 % brine was evaporated for 12 h under 1 sunlight (1 kW m−2). The distillation remained at 1.68 kg m-2h−1 for 6 h and the photothermal conversion efficiency reached 99.0 %. Additionally, the evaporator has shown impressive results in treating wastewater. The combination of high efficiency, low cost, and easy preparation makes the Janus interface evaporator promising for the fabrication of solar steam generation systems suitable for practical desalination and wastewater treatment. [ABSTRACT FROM AUTHOR]

Interfacial evaporation through hydrogel-based evaporators is emerging as a sustainable and cost-effective strategy for drinkable water production. Herein, a specially designed bi-layer hydrogel evaporator was fabricated and used for efficient solar water desalination. With cotton linter as cellulose precursor, it was dispersed in a highly concentrated ZnCl 2 (65 %) solution, and cross-linked by epichlorohydrin to prepare cellulose composite hydrogel. After removing inorganic salts by salt-leaching, polyaniline (PANi) with broadband and wide-range light absorption was then integrated into the top surface of hydrogel through in situ polymerization to construct a bi-layer evaporator. As a solar evaporator, the water could be evaporated with a low-energy demand, and the heat from the sunlight could be confined at the interface to achieve efficient water evaporation. Therefore, the hydrogel evaporator demonstrates an optimal water evaporation rate of 3.02 kg m−2 h−1 and photothermal conversion efficiency of 89.09 % under 1 sun (1 kW m−2) irradiation. This work provides new possibilities for efficient solar water purification systems with assured water quality. [Display omitted] [ABSTRACT FROM AUTHOR]

Solar water evaporators were fabricated with wasted scrub pad (SP) and their performance for the desalination/decontamination of water was evaluated. Firstly, bare SP was utilized for the desalination of seawater obtained from Puerto Vallarta beach, Mexico. SP produced an evaporation rate (ER)/efficiency of 2.18 kg m−2 h−1/72.6 %, respectively, under natural solar light. Subsequently, the SP evaporator was coated with graphene (G) + porous BiFeO 3 (BFO) microparticles. This SPG + BFO evaporator produced an outstanding evaporation rate/efficiency of 2.93 kg m−2 h−1/94.6 %. Thus, the evaporation rate and evaporation efficiency increased by 33 % and by 22 % after adding the graphene + BFO coating. Absorbance and Raman analysis on the evaporators' surface revealed that the evaporators made with graphene + BFO had higher absorbance of NIR light and higher content of defects. This favored the transformation of light to heat and steam generation. Additionally, the SPG + BFO evaporator was employed for the decontamination of water. Laundry wastewater (LWW) and domestic-wastewater contaminated with coke-soda (WCS) or coffee-drink (WCD) were also decontaminated using the SPG + BFO evaporator. The LWW contained mainly suspended solids, while the WCS and the WCD contained caffeine. The clean water obtained from the evaporation of LWW, WCS and WCD was completely free of suspended solids or caffeine as demonstrated by the FTIR and absorbance measurements. Overall, the results of this investigation demonstrate that low-cost evaporators can be fabricated from wasted scrub pads and those ones are very efficient for the evaporation/decontamination of water. Giving a second use to the wasted scrub pads benefits the environment because this delays its contamination by plastics. [Display omitted] • Solar evaporators were made with recycled scrub pads (SP) for desalination of seawater. • Adding BiFeO 3 particles to the evaporators coated by graphene increased their evaporation rate by 27 %. • The maximum evaporation efficiency for the seawater was 94.6 %. • The SP based evaporators eliminated all the caffeine from domestic wastewaters. • Laundry wastewater was completely cleaned by the SP based evaporators. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation (SDIE) is a green and sustainable technique for desalination. Hydrogel composite evaporators have been widely used for SDIE, but it is still challenging for the hydrogel evaporators to achieve uniform distribution of the light absorbing nanomaterials and at the same time possess satisfactory evaporation rate, durability and environmental applicability. We developed a 3D hydrogel evaporator with an asymmetric structure for high-efficiency SDIE. Natural kapok fibers, an important lignocellulosic plant fiber with a hollow structure, are decorated with MXene nanosheets for construction of one-dimensional photothermal conversion network. The top composite hydrogel serves as the light-absorption layer where MXene-modified kapok fibers are evenly dispersed in PVA hydrogel, while the bottom PVA hydrogel with an oriented structure acts as water delivery path. The evaporator exhibits a high solar evaporation rate and efficiency (2.49 kg·m−2·h−1 and 91.5 %, respectively) under one sun irradiation (1 kW·m−2). Even in a high salinity brine, emulsion and corrosive solutions, the evaporator can work normally with a slightly decreased evaporation rate. The 3D hydrogel evaporator with long-term stability and durability shows promising applications in purification of seawater and different waste water. [ABSTRACT FROM AUTHOR]

• 1, 3 and 5 wt% of Ni-Co co-doped SnO 2 is prepared by co-precipitation method • Tunning band gap and light harvesting ability is improved by Ni-Co co-dopants • 3 wt% of Ni-Co co-doped SnO 2 coated PF evaporator achieved evaporation efficiency of 83.62% • Developed evaporators has an ability to reduce the ion content from the seawater In this work, Nickel and cobalt (Ni-Co) are co-doped with Tin oxide (SnO 2) to prepare 1 wt% co-doped SnO 2 , 3 wt% co-doped SnO 2 and 5 wt% co-doped SnO 2 nanomaterials (NCS-1, NCS-3 and NCS-5) respectively. It is then used in interfacial solar steam generation (ISSG). The evaporation rate and evaporation efficiency of NCS-3 coated polyurethane foam evaporator is 1.334 kg m-2h−1 and 83.62 %. From the observations, Ni-Co co-doped SnO 2 nanomaterials performance is much higher than pure SnO 2. The light absorbance abilities and band gap tuning of Ni-Co co-dopant can be attributed to the improved performance of ISSG. The long-term stability of NCS-3 sample is tested under 1 kW/m2. Eventually, all the samples have proven the ability to reduce the ion content in seawater and dye removal. We suggest Ni-Co co-doped SnO 2 nanomaterial is a cost effective for energy conversion applications. [ABSTRACT FROM AUTHOR]

In the quest to improve thermal regulation within permafrost embankments, the permafrost thermosyphons equipped with horizontal evaporators remains underexplored in scholarly discourse in open. This study delineates the design and numerical evaluation of a pressure-driven two-phase closed thermosyphon (PD-TPCT), featuring a horizontal evaporator exceeding 100 m. A half-theory heat transfer model, borne from a synergy of monitoring data and the thermal resistance method, was derived from an outdoor experimentation. Considering the growing global focus on the sustainable development of the Arctic and the Third Pole, we employ this heat transfer model to analyze the long-term thermal stabilities of a PD-TPCT embankment, a PD-TPCT embankment with insulated boards, and an unprotected embankment (as a control) in the Siberian Arctic (SA) and Qinghai-Tibet Plateau (QTP). This study reveals that the horizontal installation of the evaporator can mitigate the shady-sunny slope effect and improve the thermal stability of the underlying permafrost. The SA's climate allows the PD-TPCT embankment to protect permafrost for 50 years, while in the QTP, the PD-TPCT embankment with insulated boards is needed for the same protection. The insights garnered herein offer references to both the theoretical exploration and pragmatic implementation of advanced thermosyphon with ultra-long horizontal evaporators. [ABSTRACT FROM AUTHOR]