Other subjects related to desalination:

Patent abstracts:

Desalination Key Issues

Seawater Intake

Desalination Pretreatment

Desalination Post-treatment

Desalination Polishing steps

Reverse Osmosis Desalination Process

Desalination and Energy Costs

Brine Disposal

Membranes cleaning and troubleshooting

Containerization

Instrumentation and Control

Desalination System

In accordance with particular embodiments, a desalination system includes a plurality of evaporators. The plurality of evaporators includes at least a first evaporator and a last evaporator. The plurality of evaporators are arranged in cascading fashion such that a concentration of salt in a brine solution increases as the brine solution passes through the plurality of evaporators from the first evaporator towards the last evaporator. The desalination system also includes a plurality of heat exchangers. An input of each evaporator is coupled to at least one of the plurality of heat exchangers. The system also includes a vapor source coupled to at least one of the plurality of evaporators.

Publication number: US 2008/0083605

Desalination method and system using compressed air energy systems

The invention relates to a desalination method and system that uses freeze crystallization technology that incorporates the use of compressed air energy as the source for freezing temperatures. When compressed air is released by a turbo expander, chilled air is produced as a by-product, wherein the chilled air is introduced into a crystallization chamber. Also injected into the chamber is a spray cloud of seawater droplets, which has been pre-chilled by heat exchange with the cold chamber walls, and which is then circulated and exposed to the chilled air in the chamber. The sizes of the droplets can vary, but are preferably predetermined, along with the relative temperatures, flows and speeds of the spray and chilled air, such that when the droplets are circulated within the chilled air, and settle at the bottom of the chamber, they are deposited at slightly above the eutectic temperature. This way, the ice/snow mass that forms at the bottom of the chamber will consist of frozen ice...

Publication number: US 2007/0295673

Desalination Method

Systems, methods, and apparatus for desalinating water are provided. A vessel includes a water intake system, a reverse osmosis system, a concentrate discharge system, a permeate transfer system, a power source, and a control system. The concentrate discharge system includes a plurality of concentrate discharge ports.

Publication number: US 2008/0011681

Zero waste effluent desalination system

The present invention is directed to a water desalination system that can be used in a home or commercial entity which uses a reverse osmosis or nanofilter membrane element in a unique flow configuration which promotes self cleaning of a membrane element to prevent a buildup of salts and minerals on the membrane surface. The systems use the dynamics of water usage in a water service line, not connected to the membrane to flush a recirculation/reservoir tank that feeds the reverse osmosis or nanofilter membrane periodically. The systems also produce little or no waste effluent that must be dumped into a waste system, thereby wasting water and causing an environmental problem.

Patent number: 5520816

Water desalination

A desalination plant is disclosed which includes a pump for pumping water at a pressure of between 50 and 65 Bar to a generally cylindrical filter element which includes a plurality of reverse osmosis membranes defining salt passages. Immediately upstream of the filter element there is a disc with a plurality of holes in it. The disc forms an obstruction which causes a pressure drop between the upstream side thereof and the downstream side. It also divides the water flow into a series of separate streams which impinge on the end of the filter element and flow into the salt passages. The water downstream of the obstruction is not only at a lower pressure than the water upstream of the obstruction but also is flowing turbulently. The disc and filter element are in a cylindrical casing. The brine which emerges from the filter element, and which is still at a substantial pressure, can be fed through a device such as a Pelton wheel to recover some of the residual energy therefrom.

Patent number: 6375842

Efficiency water desalination/purification

Various methods and apparatus for maximizing the efficiency of hydrate-based desalination or other water purification in open-water or partially open-water installations are disclosed. In one embodiment, water is accessed from depth where the ambient temperature is as cold as possible, which depth is other than the maximum depth of the hydrate fractionation column used in the process. The accessed water preferably is brought to reduced pressures so that gases other than hydrate-forming gases that are dissolved in the water to be treated are exsolved. Using pre-pressurized sources of hydrate-forming substances, including deep-sea natural gas deposits or supplies of liquified natural gas being transported by sea, are also disclosed. A multiple column, detachable column fractionation installation is disclosed, as is a hybrid installation having an underwater hydrate formation portion and a land-based dissociation and heat-exchange section.

patent number: 6673249

Desalination method and desalination apparatus

A desalination apparatus capable of obtaining fresh water stably at low cost by utilizing low-temperature waste, wherein the desalination apparatus including a heat exchanger 92 cooperating with an evaporation can 60 so as to subject a low-temperature waste heat 11 and raw water 62 in the evaporation can 60 to heat exchange and generate water vapor 63 in the evaporation can 60; a condenser 98 cooperating with a raw water tank 72 so as to receive the water vapor 63 from the evaporation can 60, cool the water vapor 63 by subjecting the water vapor 63 and raw water 71 in the raw water tank 72 to heat exchange and obtain distilled water 76; a distilled water tank for storing the distilled water 76; vacuum means for evacuating the evaporation can 60 and depressurizing the inside thereof so as to promote generation of water vapor 63 in the evaporation can 60; and raw water supply means for supplying raw water to the evaporation can.

2004, patent number: 6833056

Controlled cooling of input water by dissociation of hydrate in an artificially pressurized assisted desalination apparatus

Methods and apparatus for desalination of salt water (and purification of polluted water) are disclosed. Saline (or otherwise polluted) water is pumped to a desalination installation and down to the base of a desalination fractionation column, where it is mixed with hydrate-forming gas or liquid to form either positively buoyant (also assisted buoyancy) or negatively buoyant hydrate. The hydrate rises or sinks or is carried into a lower pressure area and dissociates (melts) into the gas and pure water. In preferred embodiments, residual salt water which is heated by heat given off during formation of the hydrate is removed from the system to create a bias towards overall cooling as the hydrate dissociates endothermically at shallower depths, and input water is passed through regions of dissociation in heat-exchanging relationship therewith so as to be cooled sufficiently for hydrate to form at pressure-depth. The fresh water produced by the system is cold enough that it can be used...

2002, patent number: 6830682

Diffusion driven desalination apparatus and process

A diffusion driven desalination apparatus and related method includes structure for receiving a heated water stream and creating at least one region having a thin film of water and structure for forcing a low humidity air stream over the thin film of water, wherein water from the thin film of water evaporates and diffuses into the air stream to create a humidified air stream. A diffusion tower including at least one plenum can be used to create and transfer the humidified air stream. At least one condenser, such as a direct contact condenser, condenses the humidified air stream, wherein purified water is produced. Waste heat from a power plant can be used to provide the heated water stream and power plants can use the waste heat generated to inexpensively provide purified water.

2002, patent number: 6919000

Device for desalination of water and methods of use

The present invention provides a device and method for desalinating saltwater which utilizes a heatable vessel wherein is placed a sufficient quantity of a salt which will absorb water of crystallisation and which has a dissolution index of not higher than 10-24. Saltwater is then added to the vessel and brought into contact with the salt, so that the salt will bind water from the saltwater and form a crystal hydrate. The excess saltwater with salt concentrate is drained from the vessel. The salt which has absorbed water tom the saltwater and formed a crystal hydrate is then heated in the vessel, and the pure water from the crystal hydrate is released as water vapour, which is collected and cooled to obtain desalinated water.

2000, patent number: 6866750

Equipment for desalination of water by reverse osmosis with energy recovery

The equipment for desalination of water by reverse osmosis comprises: a pump 1 for drawing the water to be salinated, a high pressure pump 25, a cylindrical block 8 housing two pistons 3, 4 connected to one another by a shaft 5 and disposed, freely slidable and liquid-tight, within respective cylinders 6, 7 being part of the same block (8) and separated from one another by a central plate 9, the latter being liquid-tight; the equipment further comprises an exchange valve 14 controlled by the position of said pistons 3, 4, as well as a cylinder or, in general, one or more containers, possibly arranged in series, in parallel or in series/parallel 15, containing one or more reverse osmosis membranes (16).

2002, patent number: 6491813

Hydrate formation and growth for hydrate-based desalination by means of enriching water to be treated

Water to be desalinated or otherwise purified is enriched by having hydrate-forming substance dissolved into it, without causing hydrate to form. Hydrate kernels are brought into contact with the enriched water to be treated, and the hydrate kernels grow outwardly into the water to be treated by incorporating dissolved molecules of the hydrate-forming substance and water from the water to be treated. Thus, substantially solid, generally spherical hydrate masses, which are preferred for hydrate-based desalination or purification, can be formed. Hydrate-forming substances can be dissolved into the water to be treated under conditions not conducive to formation of hydrate, such that hydrate does not form, using vigorous means. Hydrate-forming substance is also preferably dissolved into the water to be treated under conditions suitable for hydrate to form, but without causing hydrate to form, e.g., by being infused into the water to be treated using infusion membranes.

2003, patent number: 6890444

Apparatus and method for thermal desalination based on pressurized formation and evaporation of droplets

A method for removing dissolved solids, particularly salts, from water. An apparatus for performing the inventive method is disclosed. The aqueous solution to be treated, for example sea water, is atomized using special non-pneumatic nozzles, and sprayed into an evaporation chamber through which air, heated by waste heat, is blown. The micro-droplets undergo rapid evaporation in the chamber, resulting in the separation of the salt solids from the vapor phase of the water. The mixture of suspended solids and water vapor is filtered to remove and collect the salts, and the water vapor is condensed to collect the salt-free water.

2004, patent number: 6699369

Water desalination installation

The invention relates to a water desalination installation for the desalination of seawater according to the reverse osmosis method. This installation comprises at least one membrane module that is connected with a raw water feed line, via which raw water is supplied by means of a high-pressure pump; with a permeate line, via which the desalinated water is discharged; and with a concentrate line, via which concentrated salt water is discharged. For permitting the pressure to be adapted in the raw water feed line to the salt content and the temperature of the water to be desalinated, and for increasing at the same time the energy efficiency of such a water desalination installation, the invention proposes that provision is made for an energy recovery unit that comprises a motor-driven pressure booster pump arranged in the raw water feed line either before the high-pressure pump or between the high-pressure pump and them membrane module; and a turbine that is arranged in the concentra...

Application number: 10/587,009

Solar desalination plant

The present invention, a SOLAR DESALINATION PLANT is a water desalinating plant utilizing solar energy. It comprises of an airtight housing chamber covered with a transparent dome at its top and a transparent wall constructed over a source of saline or murky water. The chamber stands in the water and the water covers entire bottom portion inside the chamber. The surface of the water inside the chamber is covered with black floats. There is an horizontal channel in the form of an open duct above the surface of the water all around fixed to the wall inside the chamber. The channel slightly slopes down into an outlet pipe and a transparent U-tube connecting to a transparent collecting tank. A suction pump is connected between the collecting tank and a storage tank through a valve. The storage tank is also connected to the collecting tank through another valve. The transparent dome allows the sun's rays to pass through into the chamber to heat the black floats. The water that is in...

2001, Application number: 9/935,562

Method of desalination

A method of desalination of sea water is disclosed and the method comprises the steps of drawing a stream of sea water into a supplying tank; passing a high pressure air via the top end of the supplying tank; delivering sea water to a pressure tank; and performing desalination via a plurality of reverse osmosis films.

Application number: 10/265,118

Desalination System

In accordance with particular embodiments, a desalination system includes a plurality of evaporators. The plurality of evaporators includes at least a first evaporator and a last evaporator. The plurality of evaporators are arranged in cascading fashion such that a concentration of salt in a brine solution increases as the brine solution passes through the plurality of evaporators from the first evaporator towards the last evaporator. The desalination system also includes a plurality of heat exchangers. An input of each evaporator is coupled to at least one of the plurality of heat exchangers. The system also includes a vapor source coupled to at least one of the plurality of evaporators.

Application number: 11/870,174

Desalination machine

A compact and economical array of vertical tube evaporators is disclosed in a multi-effect process, for desalination of sea water, brackish water, and in general to any water with dissolved solids, in order to produce fresh water for oil offshore platforms, ships, and for some arid locations, using rejected waste heat of thermal machines. This invention is based on a concentric disposition of the evaporators or stages, having three different specially designed evaporators, which the first stage is a shell and tube evaporator built in a ring format, named Ring Shell And Tube Evaporator, including an internal shell, and having a vapour chamber above its upper tubesheet; the intermediate stage is a bundle of tubes in a ring format named Ring Bundle Evaporator, having a vapour chamber above its upper tubesheet; and the last stage that is a bundle of tubes in a circular arrangement named Cylindrical Bundle Evaporator.

Application number: 10/563,467

Osmotic desalination process

An energy efficient desalination process that does not produce waste products involves the extraction of water from a first solution, such as seawater, by using a second concentrated solution to draw the water from the first solution across a semi-permeable membrane. By manipulating the equilibrium of the soluble and insoluble species of solute within the second solution in favor of the soluble species of the solute, a saturated second solution can be used to generate osmotic pressure on the first solution. Also, by adjusting the equilibrium in favor of the less soluble species after the water has been drawn from the first solution, a portion of the solute can easily be precipitated out. Heating the second solution decomposes the solute into its constituent gasses. The constituent gasses and precipitated solute may be recycled through the process to affect the changes in equilibrium and eliminate waste products. Additionally, by using the waste steam from industrial sources and a...

2002, application number: 10/486,957

Desalination system

The invention provides methods and an apparatus for more efficiently and economically producing purified water from sea water or some other salty or brackish water source. The efficiency is derived from the co-location with a power plant or other thermal generating source that will heat the feed water. Reverse osmosis membrane filtration systems work optimally when the feed water is at certain higher temperature, where that temperature is typically higher than the feed water at ambient temperatures. By using the heated sea water as the byproduct of the power plant electricity generating process and if necessary mixing it with ambient temperature sea water, if needed to lower the water temperature, and using this feed water with a higher temperature than ambient water temperature, the efficiency of the reverse osmosis system can be increased.

2005 application number: 11/171,378



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