All-Union Conference on Softening and Desalination of Sea Water

Both brackish water desalination and seawater desalination processes are well established and in common use around the globe to create new water supply sources. The farther the location of the source water from the ocean or seashore, the lower the salinity (TDS) of the water and the lower the osmotic pressure that needs to be overcome when desalinated water is produced. This is one of the major reasons that brackish desalination is often considered less costly than seawater desalination. A number of project considerations, however, indicate that seawater desalination can be beneficial and more cost-effective than brackish water desalination. To make a fair comparison, we need to properly compare all major aspects of both types of projects to define the best and most appropriate desalination technology. While brackish water has less feed water TDS, it is more challenging to dispose of the produced concentrate. Also, although brackish water desalination needs less energy to overcome osmotic pressure, it usually requires more energy to draw the water from the well than it takes to pump seawater from the open ocean intake. Another factor is that the temperature of the brackish well water may be lower than the temperature of ocean water, giving seawater desalination an advantage in energy demand. In comparing brackish to seawater desalination, these major aspects should be evaluated: (1) Locations of seawater and brackish water plants, relative to the major consumers of the desalinated water, (2) Transportation (pumping and disposal) costs of the feed water and produced water, (3) Potential colocation of a seawater plant with a large industrial user (e.g., power plant) of the seawater for cooling or other purposes, (4) Produced quality of brackish water and seawater desalination in terms of major minerals and emerging contaminants, (5) Sustainability of the water source: capacity and depth of the brackish water wells, as well as the type of soil. (6) Technical and economic aspects of produced concentrate disposal, (7) Permitting process costs for brackish and seawater desalination, and (8) The economics of both brackish and seawater desalination treatment processes: capital costs, operational and maintenance (O&M) costs, lifetime water cost, and total water cost (TWC). This paper discusses the major evaluation criteria and considerations involved in properly comparing the economic and technical aspects of brackish and seawater desalination to determine the more favorable desalination technology for a given desalination project.

The role of desalination in bridging the water gap in Jordan

Summary Tidal current turbine is the core equipment to convert the tidal current energy. In this paper, the performance of the designed tidal current turbine is tested in the laboratory, then the impeller is used to conduct an experiment on the desalination of sea water. The sea test of the novel equipment has been done in BoHai Sea. The experimental results indicate that the efficiency of the newly developed turbine could reach up to 47.6%; the corresponding tip speed ratio is from 3.5 to 6. Under the condition of big yaw angle, the turbine could still remain high working efficiency. When the tidal current velocity exceeds 1.0 m/s, the pressure may increase to 3.5 Mpa, and under this condition, sea water can be desalinated through reverse osmic membrane. The electrical conductivity of desalinated water is around 540 μS/cm. For the experiment on hydrodynamic performance, the self-starting flow velocity of the turbine is 0.745 m/s, the staring torque is 1 Nm while about 0.97–1.0 m/s self-starting flow velocity and around 10–15 Nm starting torque for the experiment on desalination of sea water. It is believed a good attempt by using tidal current turbine in the desalination of sea water, providing the practice basis on expanding the utilization of ocean energy. Copyright © 2015 John Wiley & Sons, Ltd.

Though above 70% of the Earth is covered by water, most of the seas and oceans are unusable for drinking. Freshwater lakes, rivers and underground aquifers imply 2.5 percent of the global’s whole freshwater supply. Unfortunately, in addition to being scarce, fresh water is dreadfully unevenly spread. Enhanced demand for freshwater is a global concern. In many countries demanding is further than regular reserves. Sensible use of water, reducing spreading losses and upgraded treatment of recycled water to mitigate the concern, though, water scarcity is still presented consequently desalination of seawater is highly required. Graphene, a single sheet of carbon atoms, possibly will deliver the principal for a novel category of extremely permeable membranes for water purification and desalination. Though, a one atom thickness graphene reveals both brilliant mechanical strength and impermeability to atoms as small as helium. High-density, subnanometer pores within graphene have the potential for ultra-fast water permeance and high solute rejection as the atomic thinness makes slight resistance to stream which deters the transfer of solutes bigger than the pores. The two-dimensional, nanoporous membrane is expected to display orders-of-magnitude permeability and selectivity enhancement over current separation membranes for processes such as brackish water, water softening, or nanofiltration. This study is aimed that the existing desalination methods are not adequate to upgrade water sources unless the desalination technologies are improved significantly. Nanotechnology and utilizing graphene will deliver desalination technology to meet the requirements in the near future. Lately, novel procedures have been technologically progressed by means of nanotechnology and applying graphene for water desalination. This research will emphasize the concept of water desalination for the near futures.

Seawater desalination in China: Retrospect and prospect

Experience with plate-and-frame ultrafiltration and hyperfiltration systems for desalination of water and purification of waste water

Change of editorial structure at Social Science & Medicine

Hybrid systems in seawater desalination-practical design aspects, status and development perspectives

Hybrid membrane system for desalination and wastewater treatment : Integrating forward osmosis and low pressure reverse osmosis

the large-scale application of non-grid-connected wind power in sea water desalination industry has not only solved the difficulty in grid connection of wind power, but also can be an inexhaustible clean energy supply for the sea water desalination. Such application, breaking through the traditional sea water desalination technology and wind power development ideas and realizing the 100% local use of renewable energies, is a perfect combination of the new energy industry and the power consumption industry. The large-scale industrialization application of non-grid-connected wind power sea water desalination can not only maximize the efficiency of wind power and realize the unification of social benefit, environmental benefit and economic benefit, but also is of great strategic significance in accelerating the transformation of the economic development mode of China, and meanwhile, plays a leading role in the diversified development of the world wind power industry. 1. High-energy consumption factors restrict the development of sea water desalination Sea water desalination is a source-opening incremental technology for realizing the utilization of water resources, which can increase the total amount of fresh water and is not limited by time, space and climate with good water quality, and can guarantee the stable water supply of drinking water for coastal residents and industrial water supplementation. Since sea water desalination is the substitutional and incremental technology of fresh water resources, many countries are attaching more and more importance on it. With the rapid development of the economy and society of China, especially with the acceleration of urbanization, some coastal developed areas and large cities near the sea are having a greater and greater demand on water resources. In this condition, the development of sea water desalination has a great strategic significance in the supplementation of water resources in the sustainable development process of these areas[1,2].

Sea water desalination becomes more and more important as the consumption of fresh water. Forward osmosis (FO) is a novel technology for sea water or brackish water desalination, where a most important device, semi-permeable membrane, are required low resistance, high selection and inexpensive. In this study, based on molecular dynamic simulations, we explored the performance of porous graphene as the semi-permeable membrane for sea water desalination. Fluorine (F) and nitrogen (N) are adopted to optimize the property of graphene pore. We found that although pure pore have highest water flux (indicating lower resistance), N modified pore has the best selection due to the high electronegativity of N atoms. The about 60 L/cm2/h water flux and 100% solute rejection ratio confirm the graphene with N modified pores is good candidate as a semi-permeable membrane for sea water desalination.

Desalination of sea water through thermal and membrane based techniques and production of hydrogen through low temperature water electrolysis at facilities co-located with nuclear power plants are two areas identified for deploying co-generation projects in India in the near term. Nuclear desalination meets the requirements of clean drinking water in and around the nuclear facility, as well as to the in-house demand for high purity water for steam generation and other processes like hydrogen generation, coupled to it. Nuclear assisted hydrogen production also provides means to generate and distribute clean hydrogen which is envisaged as an important component of the decarbonized energy system of the near future. Currently the technologies for indigenous design, manufacture and quality assurance of desalination and medium scale compact water electrolysis plants are commensurate with the 220 MW(e) PHWRs presently operating in India. This work provides an overview of the research, development and deployment work carried out in these two areas in India, analyses the applicability of the IAEA Milestones Approach to nuclear cogeneration projects and discusses the problems and prospects of setting up and integrating more such facilities all over the country.

This work suggests a solution for preventing/eliminating the predicted Sea Level Rise (SLR) by seawater desalination and storage through a large number of desalination plants distributed worldwide; it also comprises that the desalinated seawater can resolve the global water scarcity by complete coverage for global water demand. Sea level rise can be prevented by desalinating the additional water accumulated into oceans annually for human consumption, while the excess amount of water can be stored in dams and lakes. It is predicted that SLR can be prevented by desalination plants. The chosen desalination plants for the study were Multi-Effect Desalination (MED) and Reverse Osmosis (RO) plants that are powered by renewable energy using wind and solar technologies. It is observed that the two main goals of the study are fulfilled when preventing an SLR between 1.0 m and 1.3 m by 2100 through seawater desalination, as the amount of desalinated water within that range can cover the global water demand while being economically viable.

Live seawater experience in Japan with hollow fiber permeators

Identification of the mixing processes in brine discharges carried out in Barranco del Toro Beach, south of Gran Canaria (Canary Islands)