Solar Energy Desalination Research Articles

Applications of different types of heat pipes in solar desalinations: A comprehensive review.

Desalination processes are energy consuming and it is required to apply clean energy sources for supplying them to prevent environmental issues. Solar energy is one of the attractive clean energy sources for desalination. In solar thermal desalination systems, different thermal components could be used for heat transfer purpose. In solar desalination technologies, heat pipe as efficient heat transfer mediums could be employed to transfer absorbed and/or stored thermal energy. The objective of this study is to review applications of heat pipes in solar energy desalination systems. Regarding the performance dependency of these thermal systems on the variety of factors, scholars have investigated these systems by consideration of the effect of different influential factors. Based on the results, it is concluded that use of heat pipes could lead to proper performance of solar desalination systems. Aside from direct transfer of absorbed heat from solar radiation, heat pipes can be applied in the storage units of solar desalination systems to keep the systems active in night-hours or low solar irradiation conditions. The overall performance of the solar desalinations systems with heat pipes can be influenced by some factors such as filling ratio and operating fluid that affect the performance of heat pipes.

Socio-economic Importance of Solar Desalination of Local Water Bodies: A Case Study of Uburu and Okposi Lakes, Ebonyi State, Nigeria

Purpose: Access to clean and potable water supply is the priority of many nations including the government of Nigeria towards socio-economic emancipation of the people. Due to increasing population expansion and water pollution, shortage of freshwater has become very common to many nations, particularly to the developing countries. To overcome the growing freshwater shortage, desalination has been proven to be the best alternative option towards freshwater provision for domestic and industrial applications. Desalination could be either thermal or electric methods which include multi-stage flash distillation (MSFD), multiple-effect distillation (MED), reverse osmosis (RO), or solar desalination. The innovation of solar still technology in recovery of fresh water from saline waters makes solar desalination simple and economical. A survey of socio-economic importance of solar energy desalination of saline lake waters at Uburu and Okposi communities, Ebonyi State, South eastern, Nigeria was conducted.
 Methodology: A survey research design was adopted for the study in order to address an age long tradition of fuel wood utilization in salt processing activity by the local women folk of Uburu and Okposi communities using saline water from the local lakes.
 Results: The survey showed that about 1,200 women were involved in the salt production activity utilizing about 26,000 tons of fuel wood per year. Translating this into monetary terms amounts to about US$$1.5 million per year. Socio-economic lives of people in the communities were negatively affected because fuel wood utilization in salt production adversely results to deforestation, environmental pollution and high cost of fuel wood in the communities. The quality and quantity (output) of salt recovering process were not commiserating to time, energy and monetary input in the process. It was observed that the distillate (freshwater portion) of the salt recovery from the saline water was not considered as an important component of the salt extraction process. This is because the salt producers were only interested on the salt extract as the only useful output of the extraction process. Recovery of freshwater component of the process could be an additional valuable income if considered.
 Unique Contribution to Theory, Policy and Practice: For sustainable salt production and freshwater recovery from the process solar desalination method was recommended for salt processing in the communities. The incorporation of solar desalination system into the age long traditional known method of salt processing will enhance salt production and boast socio-economic activities in the communities. A study of this kind is likely to help solve a major problem of acute water shortage in some communities whose water bodies are salty. The study could be a useful tool for policy makers in making rational policy that would improve and enhance salt and fresh water production as an enterprise.

Discussion on the Integrated Teaching Mode of Science and Education Based on PBL—"Take Solar Energy Desalination Xinjiang Salt-Alkali Water Treatment" as an Example

Discussion on the Integrated Teaching Mode of Science and Education Based on PBL—"Take Solar Energy Desalination Xinjiang Salt-Alkali Water Treatment" as an Example

Current and Future Challenges of Nanomaterials in Solar Energy Desalination Systems in Last Decade

Renewable energy plays key role in developing any nation. Freshwater is sometimes hard to get to in places that are far aside or poor. Because of this, it is important to have a cheap and effective desalination system that helps these communities grow and helps society as a whole. For example, the development of nanotechnology could help solve water problems by making it easier to get rid of viruses, bacteria, and other contaminants and lowering the cost of purification processes. Desalination is a process that uses a lot of energy and is responsible for most of the costs of running the plant. Also, a lot of the power comes from the greenhouse gas emissions and traditional fossil-fuel-fired power plants which pose a serious danger to ecosystem. In the last few years, many studies have been done on the use of nanotechnology in desalination, the treatment of brine, and the role of renewable energy in desalination. The main goal of this paper is to look at the most important new developments in desalination nanotechnology with respect to energy. Some conclusions and suggestions for future research are made based on the progress made and the problems that still need to be solved.

Solar energy desalination distillate yield and cost evolution, and statistical relationship between meteorological variables and distillate yield

In this paper, a hybrid solar desalination system was fabricated and incorporated with a water heater powered by a photovoltaic (PV) system. It was experimentally evaluated at Universiti Teknologi Petronas, Malaysia. Daytime operating conditions without the use of a PV system were considered for the conventional operation, while the use of PV alone or combined with direct solar radiation was considered as the modified system. This study was carried out to determine the freshwater yield, weather variabilities impact on yield, economic analysis, and system efficiency of hybrid solar desalination systems. An encyclopaedic review of five years of different researchers from different countries was critically analysed and compared with this study to see their trends and relationship. Within the study period, solar still distillate cost ranges from 0.0051 to 0.8857$/L, and 0.006 to 0.789$/L for the modified and conventional systems respectively. Similarly, the distillate cost for this study is 0.0374$/L and 0.0892$/L for the conventional and modified systems respectively. Also, the distillate yield ranges from 0.93 to 24.3 L/m2.day with an average of 12.1 L/m2.day, for the modified system, and 0.55 to 6.63 L/m2.day with an average of 3.35 L/m2.day for the conventional systems. The hourly system efficiency is 30.07 %, and 8.29 % for the modified and conventional systems respectively. Solar still is economically reasonable with good efficiency as obtained from the result. The findings also suggested that researchers should target a distillate yield of at least 6 L/m2.day and a distillate cost of 0.2$/L or lower for innovation, for a good and economical system.

A solar energy desalination analysis tool, sedat, with data and models for selecting technologies and regions

There is interest for desalination technologies powered by solar energy as arid areas are typically bestowed with good solar potential. In response to a US DOE call for solar desalination analysis tools, we developed an open-source solar energy desalination analysis tool, sedat, for techno-economical evaluation of desalination technologies and selection of regions with the highest potential for using solar energy to power desalination plants. It is expected that this software will simplify the planning, design, and valuation of solar desalination systems in the U.S. and worldwide. Sedat uses Dash for integrating various layers of large volumes of GIS data with Python-based models of solar energy generation and desalination technologies. It derives time-series of energy generation and water production, with details of plant performance and suggestions for improving the solar-desalination coupling. This paper summarizes the various phases of the tool’s development, presents example results showing the potential, under multiple objectives, of solar desalination in parts of the U.S. southwest, and discusses method details that would be useful for future model development.

A high-efficient and ultra-strong interfacial solar evaporator based on carbon-fiber fabric for seawater and wastewater purification

Interfacial solar-driven water evaporation is an effective strategy to solve freshwater scarcity. Efficient interfacial evaporation comes from excellent photothermal material. Herein, we developed a multilayer carbon-fiber fabric (MCF) evaporator with excellent mechanical properties for efficient solar-driven water purification. The all‑carbon composition and multilayer honeycomb structure endows the MCF with a high broadband light absorption (97%), rapid water transport, and good thermal management. As a result, the MCF shows an impressive purification capacity for seawater and organic wastewater and a good inhibition for the volatilization of low-boiling-point organic components. Under 1 sun irradiation, the evaporation rate can reach 3.39 kg∙m−2∙h−1. The outstanding salt-rejecting property also enables perfect stability and reusability. Even 20 wt% brine has no impact on the evaporation process and energy efficiency. More importantly, the MCF can effectively resist mechanical destruction from the environment, maintain its structural integrity. The concept of MCF with a hierarchical structure and multiple attributes will stimulate more inspiration for the development of solar-energy desalination and sewage treatment.

Potential of solar desalination for irrigation in Tunisia

In arid countries like Tunisia, the need to find new sources of water for irrigation has become imminent. Desalination of seawater can be an alternative to irrigation. In this article, we take a look at the leading food companies specializing in desalination for irrigation around the world and the prospects for the solar energy desalination potential for irrigation in Tunisia. We have noticed that several companies invest money to desalinate water for agricultural purposes. However, the cost of a cubic meter of water sometimes remains high to go forward in this new technology.

Improving the water transpiration in a solar steam generation device

Abstract Solar steam generation (SSG) has been proposed as one of the most advanced techniques to trigger solar energy desalination of sea water. Although many efforts have been dedicated to develop SSG devices, the efficiency remains relatively low. Previous work was mainly focused on thermal insulation film and light absorption. Attention has seldom been concentrated on device structure. Inspired by the manner of water transportation within flowers, we designed an artificial SSG unit which can effectively speed up the water transpiration from the bulk to the surface. Another advantage of such a device is that steam generation is separated from the bulk salty solution and thereby the solar thermal evaporation can be improved greatly. As demonstrated via the desalination experiment, the mass change and evaporation rate under 1 solar irradiation can reach as high as 2.51 kg/m2 and 1.26 kg/m2·h−1, respectively. Meanwhile, the evaporation efficiency is 74%. These values are much higher than those of traditional SSG devices and bulk water.

Experimental Research on the Operation of Solar Energy Desalination System

This paper demonstrates a self-made solar energy desalination system of pouring falling film evaporation and condensation and multi-effect heat return, which adopts solar energy heat gathering system as the heat source and wind-power generation as the power supply, realizing the optimal matching of the whole system. The practical operation of the system is tested and the results show that the water yield per heat gathering area unit reaches 12 kg/m2·d when the solar radiation is 20MJ/d. Also, this paper explores and analyzes the main factors influencing the water yield, so as to figure out the favorable operating parameters.

Investigation of a novel small-scale solar desalination plant

The investigation of a novel solar energy desalination plant is the subject of this paper. In this plant, the evaporation occurs at low pressure and temperature. The novelty of the process lies in the reduction of the pressure simply due to the height of the evaporator. A mathematical model was developed and a prototype plant was constructed and tested by varying the heat input, evaporator pressure and feedwater flowrate at different working temperatures. Experimental results are very close to the theoretical results and indicate the validity of the model and the potential of the system. Copyright , Manchester University Press.

Solar energy desalination for arid coastal regions: development of a humidification–dehumidification seawater greenhouse

The long-term aim of our research is to develop humidification–dehumidification desalination technology for farms in arid coastal regions that are suffering from salt-infected soils and shortages of potable groundwater. The specific aim of our current study was to determine the influence of greenhouse-related parameters on a process, called Seawater Greenhouse, which combines fresh water production with growth of crops in a greenhouse system. A thermodynamic model was used based on heat and mass balances. The dimension of the greenhouse had the greatest overall effect on the water production and energy consumption. A wide shallow greenhouse, 200 m wide by 50 m deep gave 125 m 3 d −1 of fresh water. This was greater than a factor of two compared to the worst-case scenario with the same area (50 m wide by 200 m deep), which gave 58 m 3 d −1. Low power consumption went hand-in-hand with high efficiency. The wide shallow greenhouse consumed 1.16 kW h m −3, while the narrow deep structure consumed 5.02 kW h m −3. Analysis of the local climate indicated that the structure should be built facing the NE direction. We are also in the process of building a commercial size Seawater Greenhouse at a site by the sea. The aim is to demonstrate the technology to local farmers and companies in the Arabian Gulf. The system will allow for the reclamation of salt-infected land by not relying, at all, on groundwater resources.

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.

Water from fossil aquifers as a potential supply source for solar desalination plants on a regional scale

Research carried out on the hydrogeology and hydrogeochemistry of the water in the Judea Kurnuk and Arad Group aquifers in the Negev (Cenomanian. Lower Cretaceous and Jurassic) reveals that under a large area of the Negev an aquiferous section 1000 m to 1500 m thick is saturated with brackish water. Data derived from oil and water wells enabled the mapping of the distribution of the various water groups, which in turn made it possible to map the chemical composition of the water in the different regions. Thus, southeast of the line running from Masada on the Dead Sea to Ayun Musa on the Suez Gulf, water of approximately 5 g/l TDS can be found in the Judean (Cenomanian) and Kurnuk (Lower Cretaceous) Groups and of about 10 g/l TDS in the Arad Group (Jurassic). The potential quantities of water, from the point of view of storage, are in the order of magnitude of hundreds of billions of cubic meters. Annual pumping amounts, however, are a function of management policy. According to recent research, the annual pumping potential for the next thirty years from the Kurnub Group (Lower Cretaceous) is about 60 to 100 million cubic meters, with an allowance of 20–100 meters for the reduction of head. The Judea Group (Cenomanian Turonian) and Arad Group (Jurassic) can be reached in the northern Negev and still another potential Paleozoic aquifer (with water of about 12 g/l TDS) is available in the southern Arava. Quantitative pumping potential figures are not yet available for these aquifers. However, a very rough estimate suggests that the potential may amount to several tens of millions of cubic meters over the next fifty years. In addition to the direct use of this water for agriculture and industry (Arava farms, Phosphate and Dead Sea Works), as well as desalination by the RO method, it is suggested that the possibility of using this water for solar energy desalination be investigated on a regional scale. The cost of desalination may be reduced if one takes water whose salinity is a little above the threshhold of direct application for agricultural use and mixes it with the distilled water supplied by the solar distiller. The chances of achieving even lower costs for distilled water are promising as the water pumped has an average temperature of 40°C. Thus, the efficiency of the solar still may be greater, and may even enable night distillation to take place. The application of solar distillation thus appears promising in the Arava, where the special climatic conditions give a marginal benefit value of $1.00 per cubic meter of water for winter for winter vegetables. Along the dead Sea coast, this looks even better.

Trends in the application of solar energy to water desalination

Although water desalinated by solar energy should be inexpensive, this is not the case. The energy is scattered free. However, in order to make use of it, expensive energy collecting systems have to be installed. With presently implementable technology, desalination by solar energy is more expensive than desalination by fossil energy owing to the high capital charges on the costly investments in solar energy collecting systems. A typical example following an evaluation of desalination using multipleeffect vertical tube evaporators having a capacity of 4,200,000 cubic meter per annum is as follows(prices are for 4th quarter of 1979): Fossil energy Solar energy Estimated fixed capital investment ($) 21,400,000 103,200,000 1 Estimated cost of water ($/m 3) 1.6 2 2.7 3 Smaller solar energy desalination units will yield fresh water at higher costs.The predominant factor of costs is capital charges. It is obvious that efforts should be made to develop cheaper desalination systems, in particular cheaper solar energy collecting units. The optimal solution can differ for specific cases. Processes can be more attractive in small scale plants, however, less attractive in large scale plants and vice versa. Specific local conditions, including even availability of land or of professional manpower can influence the choice.