Solar Desalination Device Research Articles

Fabrication of 3D-Printed Ceramic Structures for Portable Solar Desalination Devices.

This paper proposes the fabrication process of the first fully 3D-printed ceramic core structures for portable solar desalination devices optimized to tackle water scarcity from an energy and sustainability perspective. Robocasting, a 3D printing technique, is utilized to fabricate a fully ceramic structure of an integrated solar absorber/thermal insulator/water transporter based on the two-layered structure of modified graphene on silica (MG@Silica) and the porous silica structure. Robocasting has demonstrated its flexibility in tailoring structural designs, combining nanopores and microchannels that exhibit uniform water transport delivery and thermal insulation. This portable device can be used immediately to collect fresh drinking water without an additional setup. It possesses a water evaporation rate of 2.4 kg m-2 h-1 with a drinking water production capacity of 0.5 L m-2 h-1. This novel device has shown excellent ion rejection ability, with the collected water meeting the World Health Organization (WHO) drinking water standards.

Poly(ionic liquid)-crosslinked graphene oxide/carbon nanotube membranes as efficient solar steam generators

Graphene oxide (GO) is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis, but the easy delamination of GO in water poses a critical challenge for practical solar desalination. Herein, we improve the stability of GO membranes by a self-crosslinking poly (ionic liquid) (PIL) in a mild condition, which crosslinks neighbouring GO nanosheets without blemishing the hydrophilic structure of GO. By further adding carbon nanotubes (CNTs), the sandwiched GO/CNT@PIL (GCP) membrane displays a good stability in pH = 1 or 13 solution even for 270 days. The molecular dynamics simulation results indicate that the generation of water nanofluidics in nanochannels of GO nanosheets remarkably reduces the water evaporation enthalpy in GCP membrane, compared to bulk water. Consequently, the GCP membrane exhibits a high evaporation rate (1.87 kg m−2 h−1) and displays stable evaporation rates for 14 h under 1 kW m−2 irradiation. The GCP membrane additionally works very well when using different water sources (e.g., dye-polluted water) or even strong acidic solution (pH = 1) or basic solution (pH = 13). More importantly, through bundling pluralities of GCP membrane, an efficient solar desalination device is developed to produce drinkable water from seawater. The average daily drinkable water amount in sunny day is 10.1 kg m−2, which meets with the daily drinkable water needs of five adults. The high evaporation rate, long-time durability and good scalability make the GCP membrane an outstanding candidate for practical solar seawater desalination.

Versatile photonic band gap materials for water desalination

In this paper, we have obtained a novel way using photonic crystals by theoretical studies to water desalination. Here, in the present design, we are coupling between pyramids and porous structures to yield an efficient solar desalination device. The designed structures from titanium nitrate (TiN) coated with titanium dioxide (TiO2) which float on the water surface can efficiently absorb a wide-ranging solar spectrum (>90 %). Thus, the TiN/TiO2 structure is a promising material in the field of seawater desalination by thermal techniques. Moreover, the pyramids shapes on the top of the optical devices have a good ability for light trapping. We have designed the proposed structure using COMSOL multiphysics simulation which it is based on the basic principles of the finite element method (FEM).

Water desalination using solar continuous humidification–dehumidification process using hygroscopic solutions and rotating belt

In this study, solar energy is utilized for providing fresh water by purification of tab water using rotating belt utilizing the addition of hygroscopic solutions containing kaolin or calcium chloride. The function of the hygroscopic solution is to increase the surface area and thus the percentage of evaporation on the rotating belt. It was shown that the use of hygroscopic material enhances the production of fresh water to a significant level. Additionally, the use of kaolin has been shown to be superior to the use of calcium chloride. The use of kaolin in the proposed solar desalination device has increased solar desalination from 10.8 kg/m2·day of using pure tap water to 32.1 kg/m2·day. A mathematical model was established to the use of hygroscopic material in this solar desalination using rotating belt. It was found that the maximum system efficiency was 61% after utilizing kaolinite; approximately seven times more comparing to the efficiency without using kaolinite (8.7%).

Design development and performance evaluation of concentrating solar thermal desalination device for hot arid region of India

Design development and performance evaluation of concentrating solar thermal desalination device for hot arid region of India

Three-dimensional solar steam generation device with additional non-photothermal evaporation

The evaporation sites of a solar desalination device were expanded from conventional 2D to a new type of 3D by leaving the side area of the porous water transporter exposed to the air. The 3D solar desalination device permits not only photothermal distillation by the photoabsorbers at the top under sunlight illumination, but also additional non-photothermal evaporation on the side of the water transporter that works even at night by exploiting environmental heat. For the first time, we developed a unique configuration of water transport exposed to the environment with a great contribution to an active site increase and confirmed the significant impact of the active site increase on the solar desalination performance by systematic and strong pieces of evidence. Due to the effective utilization of enormous evaporation sites on the top and side surfaces in the 3D configuration, the device exhibited a significant steam generation rate of ~0.74 g/h under 1 sun illumination, which is ~1.5 times higher than the maximum value achieved with photothermal evaporation only. Our study suggests an innovative change which incorporates additional non-photothermal evaporation in the solar desalination device can be a straightforward and efficient way to address clean water deficiencies worldwide in the future.

Experimental research on four-stage cross flow humidification dehumidification (HDH) solar desalination system with direct contact dehumidifiers

A novel Four-stage cross flow humidification and dehumidification (HDH) solar desalination system with direct contact dehumidifiers was proposed in this paper. Firstly, the composition and operation principle of the system were introduced. Then, the heat and mass exchange models of main parts in the system were established, and some indexes to evaluate system performance were given. Next, an indoor experiment was set up and tested. Based on the experimental results, this paper analyzed the effects of seawater spraying temperature, spraying quantity and the air volume flow rate on freshwater production rate and the gain output ratio (GOR). Finally, the economic analysis and freshwater yield per unit volume of this system were discussed. The results show that when Ts1 = 83 °C, ms1 = 1.1 t/h and mc1 = 0.94 t/h, the water yields of the HDH system with 560 m2 total heat transfer area are 47 kg/h and 63 kg/h respectively under V·a = 0 m3/h and V·a = 300 m3/h. Compared with conventional systems, the current system has higher water yield per unit volume (34.1 kg/(m3·h)) and lower pure water yield cost (3.86 $/ton) when the investment cost of the whole solar desalination device with 42 m2 solar collectors is about $ 6563.

Efficient Solar-Thermal Distillation Desalination Device by Light Absorptive Carbon Composite Porous Foam.

Solar‐thermal driven desalination based on porous carbon materials has promise for fresh water production. Exploration of high‐efficiency solar desalination devices has not solved issues for practical application, namely complicated fabrication, cost‐effectiveness, and scalability. Here, direct solar‐thermal carbon distillation (DS‐CD) tubular devices are introduced that have a facile fabrication process, are scalable, and use an inexpensive but efficient microporous graphite foam coated with carbon nanoparticle and superhydrophobic materials. The “black” composite foam serving as a solar light absorber heats up salt water effectively to produce fresh water vapor, and the superhydrophobic surface of the foam traps the liquid feed in the device. Two proof‐of‐principle distillation systems are adopted, i.e., solar still and membrane distillation and the fabricated devices are evaluated for direct solar desalination efficiency. For the solar still, nanoparticle and fluorosilane coatings on the porous surface increase the solar energy absorbance, resulting in a solar‐steam generation efficiency of 64% from simulated seawater at 1 sun. The membrane distillation demonstrates excellent vapor production (≈6.6 kg m‐2 h‐1) with >99.5% salt rejection under simulated 3 sun solar‐thermal irradiation. Unlike traditional solar desalination, the adaptable DS‐CD can easily be scaled up to larger systems such as high‐temperature tubular modules, presenting a promising solution for solar‐energy‐driven desalination.

Performance evaluation and economic analysis of solar desalination device made of building materials for hot arid climate of India

Performance evaluation and economic analysis of solar desalination device made of building materials for hot arid climate of India

Mesoporous Three-Dimensional Graphene Networks for Highly Efficient Solar Desalination under 1 sun Illumination.

Solar desalination via thermal evaporation of seawater is one of the most promising technologies for addressing the serious problem of global water scarcity because it does not require additional supporting energy other than infinite solar energy for generating clean water. However, low efficiency and a large amount of heat loss are considered critical limitations of solar desalination technology. The combination of mesoporous three-dimensional graphene networks (3DGNs) with a high solar absorption property and water-transporting wood pieces with a thermal insulation property has exhibited greatly enhanced solar-to-vapor conversion efficiency. 3DGN deposited on a wood piece provides an outstanding value of solar-to-vapor conversion efficiency, about 91.8%, under 1 sun illumination and excellent desalination efficiency of 5 orders salinity decrement. The mass-producible 3DGN enriched with many mesopores efficiently releases the vapors from an enormous area of the surface by heat localization on the top surface of the wood piece. Because the efficient solar desalination device made by 3DGN on the wood piece is highly scalable and inexpensive, it could serve as one of the main sources for the worldwide supply of purified water achieved via earth-abundant materials without an extra supporting energy source.

Plasmonic Graphene Polyurethane Nanocomposites for Efficient Solar Water Desalination

Solar energy is the cleanest and most abundant renewable natural resource available. Materials for solar photothermal energy conversion are highly sought after for their cost savings, clean environment, and broad utility in providing water heating and/or steam for many applications including domestic water heating and solar-driven desalination. Water desalination via solar steam generation is considered one of the most important technologies to address the increasing pressing global water scarcity. The current solar thermal systems rely on the use of copper or aluminum for absorbers which have limited utility because of their inflexibility for tailored applications, high cost, and limited availability. These bulk metals are not very efficient in absorbing the solar spectrum. Therefore, the current solar thermal desalination devices have low efficiency and low water productivity due to the ineffectiveness of solar collectors to convert most of the sun energy into heat. Herein, we report the development of ...

Economic analysis of a household solar desalination device integrated with photo thermal and photovoltaic

Economic analysis of a household solar desalination device integrated with photo thermal and photovoltaic

Graphene oxide-based efficient and scalable solar desalination under one sun with a confined 2D water path

Because it is able to produce desalinated water directly using solar energy with minimum carbon footprint, solar steam generation and desalination is considered one of the most important technologies to address the increasingly pressing global water scarcity. Despite tremendous progress in the past few years, efficient solar steam generation and desalination can only be achieved for rather limited water quantity with the assistance of concentrators and thermal insulation, not feasible for large-scale applications. The fundamental paradox is that the conventional design of direct absorber-bulk water contact ensures efficient energy transfer and water supply but also has intrinsic thermal loss through bulk water. Here, enabled by a confined 2D water path, we report an efficient (80% under one-sun illumination) and effective (four orders salinity decrement) solar desalination device. More strikingly, because of minimized heat loss, high efficiency of solar desalination is independent of the water quantity and can be maintained without thermal insulation of the container. A foldable graphene oxide film, fabricated by a scalable process, serves as efficient solar absorbers (>94%), vapor channels, and thermal insulators. With unique structure designs fabricated by scalable processes and high and stable efficiency achieved under normal solar illumination independent of water quantity without any supporting systems, our device represents a concrete step for solar desalination to emerge as a complementary portable and personalized clean water solution.

3D self-assembly of aluminium nanoparticles for plasmon-enhanced solar desalination

Self-assembling aluminium nanoparticles are used to make a plasmon-enhanced device for desalination. Plasmonics has generated tremendous excitement because of its unique capability to focus light into subwavelength volumes1, beneficial for various applications such as light harvesting2,3, photodetection4, sensing5, catalysis6 and so on. Here we demonstrate a plasmon-enhanced solar desalination device, fabricated by the self–assembly of aluminium nanoparticles into a three-dimensional porous membrane. The formed porous plasmonic absorber can float naturally on water surface, efficiently absorb a broad solar spectrum (>96%) and focus the absorbed energy at the surface of the water to enable efficient (∼90%) and effective desalination (a decrease of four orders of magnitude). The durability of the devices has also been examined, indicating a stable performance over 25 cycles under various illumination conditions. The combination of the significant desalination effect, the abundance and low cost of the materials, and the scalable production processes suggest that this type of plasmon-enhanced solar desalination device could provide a portable desalination solution.

Performance analysis and experimental comparison of three operational modes of a triple-effect vertical concentric tubular solar desalination device

This paper presents an experimental investigation and performance analysis of a novel triple-effect vertical concentric tubular solar desalination unit. The productivity and thermal efficiency of the device for three operational modes (e.g., single-, double- and triple-effect) were tested and compared under the fixed heating power and controlled heating temperature conditions, respectively. The temperature in different measured points in the device was tested. Also, Gain Output Ratio (GOR) of the system was calculated for three operational modes. The experimental results indicate that the fresh water production for the triple-effect mode can reach 1.162kg/h at the heat input of 400W. The GOR of the device for the double-effect and triple-effect modes can reach about 1.21 and 1.89 under the condition of fixed heat input. The experimental results are then compared with the numerical results, and it is found that the trend of the experimental results is consistent with the theoretical water production rate. The economic analysis results show that the production cost of water is about 6.6$/ton, which implies an excellent application prospects of the designed desalination device.

Performance analysis and experimental verification of a multi-sleeve tubular still filled with different gas media

A novel nonconcentrical multi-sleeve tubular still for triple-effect solar desalination device is described in this study. An experimental and analytical analysis is given to investigate how the water production performance is affected by different gas media, which are air, oxygen, helium and carbon dioxide. The water production rate and the temperature value of every measured point inside the device with different gas media were obtained through the experiments. Experimental results show that, when the heating temperature is 85°C and the gas medium is oxygen, the water production rate can reach to 0.58kg·h−1. It is increased by 31.82% compared with the rate when the gas medium is air. In addition, the internal heat and mass transfer mechanism of the device with different gas media was analyzed. The semi-empirical expression of the water production rate is given. According to the experimental data, the Dv under different conditions is obtained. The results obtained are then compared against the experimental results, and it is found that the trend of theoretical water production rate is consistent with the experimental results. The reasons for deviation are analyzed.

Solar Straight Thermal Circumfluence Closed-End Seawater Desalination System Analysis

This paper studies a small prototype of solar desalination device, using the method of directly heating sea water and a double negative pressure evaporation room in the desalination operation. The system uses common sea water, it is cost-effective and can make full use of low-grade solar energy. More over, and the wind power can provide energy for the whole electrical control system, realizing the full closed automation. Through testing and analyzing, the relationship between the main parameters of the system is confirmed; this lays the theoretical foundation for matching each parameter of the whole system, and helps to determine the optimal desalination method.

A solar adsorption desalination device: first simulation results

This paper describes a multi-effect desalination system operating with an adsorption heat pump with an open cycle and using zeolite as the solid vapor adsorbent. The water production and energy consumption of the system were studied using a theoretical model.

An overview of solar desalination for domestic and agriculture water needs in remote arid areas

The work was motivated by the increasing awareness of the need for enhancing water supplies schemes in arid lands featuring an appropriate technology for solar energy use in the desalination field. This paper has investigated (1) presentation of the world water resources in the main arid zones in the world; (2) identification of the different solar energy desalination devices applicable to remote arid areas and suitable for its use for potable and agriculture purposes; and (3) assessment of factors relevant to the implementation of solar desalination units such as economical consideration, technical and operational appropriateness. The assessment of these points shows that solar energy can make a considerable contribution to remote arid areas fresh water supply for domestic or agriculture use. Solar desalination for irrigation by using a solar still combined with greenhouses is stressed. Detailed economic analyses of the above are considered essential. Recommended research topics leading to high efficiency of solar desalination devices are highlighted.