DE102012205674A1 - Magneto hydrodynamic turbine for recovering electric power from charge carrier-containing fluid supplied by e.g. sea water desalination system, has chamber provided with segmented electrodes, where fluid is flowed through chamber - Google Patents

Abstract

The turbine (14) has a chamber provided vertical to a flow direction of a magnetic field, where a charge carrier-containing fluid is flowed through the chamber with velocity (v). The fluid is supplied from a system in which concentration of charge carriers is highly enriched, where the system restricts a solution by evaporation of a solvent. The chamber is provided with segmented electrodes (17) vertical to the flow direction and the magnetic field. The magnetic field is produced by permanent magnets i.e. rare-earth permanent magnets. An independent claim is also included for a method for recovering energy from a charge carrier-containing fluid.

Description

The invention relates to a magneto-hydrodynamic turbine for use in systems with agitated salt solutions, in particular desalination plants.

Magneto-hydrodynamic turbines are known as devices for generating energy from flowing media. An essential requirement of the working medium is the presence of charge carriers. These are deflected during their flow movement by an applied magnetic field until they hit an electrode to give off electrical energy there.

The US 41,151,423 shows a magneto-hydrodynamic generator to be fed with the energy of changing tides. The seawater has load carriers, a certain speed and above all an almost unlimited availability. The generator has a magnetic field generated by coils, the generator being incorporated directly into the flow of tides. The construction shown has the disadvantages that the entire generator is exposed to severe corrosion, the flow velocity is very slow, the salt concentration rather low, and thus the performance of the generator is severely limited.

The present invention seeks to take advantage of the basic principles of the described magneto-hydrodynamic energy conversion without being limited by the disadvantages described. The magneto-hydrodynamic turbine consists of a space which is traversed by a fluid containing a charge carrier at a speed, wherein the space is traversed perpendicular to the flow direction of a magnetic field and perpendicular to the flow direction and the magnetic field segmented electrodes are provided. Nothing should come into contact with the fluid except the inner surface of the flow-through space.

The solution provides that the fluid is supplied from a system in which the concentration of the contained charge carriers is greatly enriched. This has the advantage that the charge carrier concentration can be high, in addition, the speed of the fluid can be set high. Both parameters strongly increase the yield of electrical energy during this procedure.

In one embodiment, the plant is a desalination plant. When using the obtained in the desalting Brine so the salt coatings, this has the advantage that the fluid is already highly enriched with salts. In this way, the waste product from the desalination can still use. In addition, this Brine is free of interfering solids, since the water used for the desalination is highly purified.

In a further embodiment, the system concentrates the solution, in particular by evaporation of the solvent. For the magneto-hydrodynamic conversion of the energy from a kinetic form into an electrical one, it is particularly advantageous if the salt concentration is particularly high and the solvent concentration is particularly low.

In another embodiment, the plant is an osmosis and / or reverse osmosis plant. In these plants also salts and solvents are separated. The resulting products are very suitable for the use of a magneto-hydrodynamic turbine according to the invention, because they can be supplied to this by piping.

In a further embodiment, the magnetic field is generated by permanent magnets, in particular by rare earth permanent magnets. The rare earth permanent magnets provide a magnetic flux density of several Tesla, which already at a correspondingly high salt concentration, a good part of the kinetic energy of the fluid can be converted into electrical energy.

In a further embodiment, the space through which it flows has a narrowing in the region of the greatest magnetic field. This constriction has the effect of a nozzle, the fluid is accelerated, the energy conversion can be greatly increased.

The invention also describes a method for recovering energy from a carrier fluid-containing fluid, wherein the fluid is passed through a previously described magneto-hydrodynamic turbine. Especially when the wastewater from a seawater desalination plant, the brine enriched with salt by a magneto-hydrodynamic turbine directs, you have the opportunity to use an energy that is otherwise generally unused discharged into the sea.

Reference to an embodiment of the invention will be explained in more detail. The drawings show a magneto-hydrodynamic turbine according to the invention. In detail, the shows

1 a schematic flow diagram of a process for seawater desalination and

2 a schematic flow diagram of the magnetohydrodynamic turbine according to the invention.

At the in 1 shown seawater desalination is from a reservoir 1 a feed stream 2 on seawater of a first membrane unit 3 fed. The seawater is stored in the reservoir before it is stored 1 , or before the supply to the first membrane unit 3 , purified from constituents containing the semipermeable membrane 4 could damage or pollute.

In the first membrane unit 3 There is a reverse osmosis, in which the seawater under high pressure through the membrane 4 is pressed. In doing so, the osmotic pressure has to be overcome. The semipermeable membrane 4 may for example consist of polyamide, PTFE or sulfonated copolymers having a pore diameter of 5 × 10 -7 to 5 × 10 -6 mm. The membrane 4 lets water through and keeps the salts back. The first membrane unit 3 separates the feed stream 2 into a permeate stream 5 and a retentate stream 6 , At the permeate stream 5 it is largely salt-free pure water. The retentate stream 6 has a higher salt concentration than the supplied feed stream 2 ,

At least part of the retentate stream 6 becomes a second membrane unit 7 fed. In the second membrane unit 7 is located on one side of a semipermeable membrane 8th Retentate and on the other hand a solution 9 their concentration of solutes is lower than that of the retentate. In the embodiment, this seawater from the reservoir 1 the second membrane unit 7 fed.

The pressure on the retentate side of the second membrane unit 7 is lower than on the retentate side of the first membrane unit 3 , By means of a device 10 becomes the pressure difference between the first membrane unit 3 and the second membrane unit 7 used. The device 10 is between the first membrane unit 3 and the second membrane unit 7 connected.

In the embodiment is as a device 10 a pressure exchanger used. The pressure exchanger is in 1 only as a square symbol 10 shown. A detailed explanation will be given in the description of 2 ,

In the second membrane unit 7 an osmosis takes place. The driving force of spontaneous osmosis is the difference between the concentrations of one or more substances passing through the membrane 8th separate retentate side and the side with the solution 9 , The solution 9 feeds from the same reservoir 1 from the also the feed stream 2 is removed. It occurs solvent of the solution 9 through the membrane 8th , This dilutes the retentate. In the solution 9 Salts are from the membrane 8th retained. By the overflow of water through the membrane 8th the difference in the concentration of dissolved salts is reduced.

The overflow of solvent builds up on the retentate side of the second membrane unit 7 a pressure on. The pressure is generated by means of an energy recovery unit 11 used. In the embodiment, the energy recovery unit 11 the second membrane unit 7 downstream. There will be a turbine as an energy recovery unit 11 used. The diluted with water retentate flows to the turbine. The mechanical work of the turbine can be used to generate electrical energy or pumping. This increases the efficiency of the process.

After the energy recovery unit 11 The diluted retentate is passed back into the sea. The dilute retentate stream combines with a stream 12 , At the current 12 it is the solution 9 facing the pure sea water from the reservoir 1 has an increased salt concentration, since solvents from the solution 9 to the other side of the membrane 8th but the salts have been retained.

The magneto-hydrodynamic turbine according to the invention 14 is in the system between the outlet of the high pressure side of the second membrane unit 7 and the energy recovery unit 11 arranged. Here, the retentate has a speed that is suitable for energy production by means of magneto-hydrodynamic turbine 14 is very beneficial.

The 2 schematically shows the magneto-hydrodynamic turbine 14 in an oblique view. The volume flowed through 15 is bounded on the surfaces perpendicular to the flow direction of the retentate by magnetic surfaces 16 and segmented electrodes 17 , Due to the Lorentz force, charge carriers in the flowing retentate are moved by the magnetic field in such a way that the separate charge carriers on the segmented electrodes 17 can give off their electrical energy.

LIST OF REFERENCE NUMBERS

1

 reservoir

2

 Feed power

3

 membrane unit

4

 membrane

5

 permeate

6

 retentate

7

 membrane unit

8th

 membrane

9

 solution

10

pressure exchanger

11

Energy recovery unit

12

electricity

13

14

magneto-hydrodynamic turbine

15

volume flowed through

16

magnetic surfaces

17

segmented electrodes

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 41151423 [0003]

Claims (9)

Magneto-hydrodynamic turbine consisting of a space which is traversed by a carrier containing fluid at a speed (v), wherein the space is perpendicular to the flow direction of a magnetic field permeated and provided perpendicular to the flow direction and the magnetic field segmented electrodes are characterized in that the fluid is supplied from a plant in which the concentration of the contained charge carriers is greatly enriched. Magneto-hydrodynamic turbine according to claim 1, characterized in that the plant is a seawater desalination plant. Magneto-hydrodynamic turbine according to claim 1 or 2, characterized in that the system restricts the solution, in particular by evaporation of the solvent. Magneto-hydrodynamic turbine according to one of the preceding claims, characterized in that the system is an osmosis and / or reverse osmosis system. Magneto-hydrodynamic turbine according to one of the preceding claims, characterized in that the magnetic field is generated by permanent magnets, in particular by rare earth permanent magnets. Magneto-hydrodynamic turbine according to one of the preceding claims, characterized in that the flow-through space has a constriction in the region of the largest magnetic field. A method for recovering energy from a carrier containing flowing fluid, characterized in that the fluid is passed through a magneto-hydrodynamic turbine according to one of claims 1 to 6. A method according to claim 7, characterized in that in a seawater desalination plant, the salt-enriched brine is passed through a magneto-hydrodynamic turbine according to one of claims 1 to 7. A method according to claim 8, characterized in that in a seawater desalination plant, the rapidly moving influx into the plant, the so-called feed stream is passed through a magneto-hydrodynamic turbine according to one of claims 1 to 7.

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